Screw Compressor Packages
GEA Grasso M-Series
Operating Manual (Translation of the original text)
P_261511_1
COPYRIGHT
All Rights reserved.
No part of this documentation may be copied or published by means of printing, photocopying, microfilm
or otherwise without prior written consent of
•
GEA Refrigeration Germany GmbH
herein after referred to as the manufacturer. This
restriction also applies to the drawings and diagrams
contained in the documentation.
LEGAL NOTICE
These operating instructions are part of the technical
documentation for the scope of delivery. They contain important instructions for ensuring safe and
proper transport, installation, start-up, economic
operation, maintenance and repair of the unit. Their
observance helps in avoiding dangers, reducing
repair costs and down-times and increasing the reliability and durability of the unit.
These operating instructions are intended for the
users of the equipment and are specifically intended
for the operating company and its operating and
maintenance personnel.
It is essential that the operating company and its
operating and maintenance staff read these operating instructions prior to transport, installation, startup, use, maintenance, repair, disassembly and disposal. This obligation to read also applies to personnel involved in activities in the life phases of the
machine.
The operating company must supplement these
operating instructions with instructions regarding
health and safety at work and environmental protection on the basis of existing national regulations for
industrial safety.
In addition to these operating instructions and the
binding accident prevention regulations valid for the
respective country and area where the product is
used, the recognised technical regulations for safe
and professional work must also be observed.
These operating instructions are part of the unit. The
entire documentation comprises these operating
instructions and all additional operating instructions
supplied with the unit. It must be kept readily available where the unit is installed. The entire documentation must also be forwarded if the unit is installed at
another location and if the unit is sold.
These operating instructions have been written in
good faith. However, GEA Refrigeration Germany
GmbH cannot be held responsible for any errors that
this document may contain or for their consequences.
The manufacturer reserves the right to make technical modifications during the course of further development of the equipment covered by these operating
instructions.
Illustrations and drawings in these operating instructions are simplified representations. As a result of the
improvements and changes, it is possible that the
illustrations do not exactly match the unit you are
operating. The technical data and dimensions are
subject to change. No claims can be made on the
basis of them.
The manufacturer cannot accept liability for damages
•
which occur during the warranty period as a
result of
–
improper operating conditions and conditions
of use,
–
inadequate maintenance,
–
improper operation,
–
incorrect installation,
–
incorrect or improper connection of the main
electrical drive,
•
or which result from or can be attributed to
improper modifications or failure to observe the
instructions;
•
through the use of accessories or spare parts
which were not supplied or recommended by the
manufacturer.
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
2 GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015
SYMBOLS USED IN THIS MANUAL
Danger!
Stands for an immediate danger which
leads to heavy physical injuries or to
the death.
Warning!
Stands for a possibly dangerous situation which leads to heavy physical
injuries or to the death.
Caution!
Stands for a possibly dangerous situation which could lead to light physical
injuries or to damages to property.
Hint!
Stands for an important tip whose
attention is important for the designated use and function of the device.
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015 3
LAYOUT INFORMATION
Bullet points and numbered list characters
Bullet points are used to separate logical contents within a section:
•
Bullet point 1
Types of bullet point 1.
•
Bullet point 2
Types of bullet point 2.
Numbered list characters are used to separate enumerations within a descriptive text:
Descriptive text with consecutive numbering:
–
Numbered list point 1
–
Numbered list point 2
Handling instructions
Handling instructions require you to do something. Several consecutive steps result in a handling sequence that
should be run in the specified order. The handling sequence can be divided into separate steps.
Handling sequence
1.
Handling sequence step 1
–
step 1,
–
step 2,
–
step 3.
2.
Handling sequence step 2
The subsequent handling sequence is the expected result:
®
Result of the handling sequence.
Individual handling steps
Individual handling steps are marked thus:
–
Individual work steps
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
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TABLE OF CONTENTS
1
BASICS
11
1.1
Importance of the documentation
11
1.2
Requirements for personnel, obligation to exercise due care
11
1.3
Legal foundations (Germany)
12
1.4
Specified Use
14
1.5
Warning against foreseeable abusive use
14
1.6
CE mark
15
2
MANUFACTURER INFORMATION
16
3
CUSTOMER SERVICE
17
3.1
Technical customer service department
17
3.2
Spare parts
17
3.3
Training courses
17
3.4
Service contracts
17
4
SAFETY
18
4.1
General information for safety
18
4.2
Behaviour in the case of emergency
18
4.3
Possible residual hazards
18
4.4
Installation in explosive atmospheres, installation zones 1 and 2
19
5
TRANSPORT, STORAGE
21
5.1
General instructions
21
5.2
Delivery
21
5.3
Transport (crane transport)
21
5.4
Bearings
23
5.5
Storage (several years)
24
6
INSTALLATION
26
6.1
Basic information for installation
26
6.2
Rigid installation
26
6.3
Anti-vibration mounting
26
6.4
Electrical connection
26
6.4.1
Use in explosive atmospheres, installation zones 1 und 2
27
6.5
Sound insulation, weather protection
27
6.6
Information regarding noise emissions
27
7
DESCRIPTION OF DESIGN AND FUNCTION
29
7.1
Installation in explosive atmospheres, installation zones 1 und 2
29
7.2
Product code of screw compressor packages - Grasso SP1, SP2, SPduo and M Series
30
7.3
Technical specifications
32
7.4
Location of the product identification (name plate)
33
7.5
Information and safety labels on the product
34
7.5.1
Labelling of the pressure and temperature sensors, heater
34
7.5.2
Label of the safety valve
34
7.5.3
Labels of the screwed connections with DiNova ring
34
7.5.4
Labels of the pipelines
35
7.5.5
Marking the direction of rotation of the compressor drive motor
35
7.5.6
Marking the direction of rotation of the oil pump motor
35
7.5.7
Labels of the pressure gauge
36
7.5.8
Labeling of the control / control cabinet
36
7.5.9
Designation of the earth connection
37
7.6
Process flow diagram
37
7.7
Main components
38
7.7.1
Screw compressor
39
7.7.2
Compressor drive motor
39
7.7.3
Compressor with coupling housing
40
7.7.4
Oil separator
40
7.7.5
OMC block with oil filter system
41
7.7.6
Oil cooler
41
7.7.7
Oil pump (optional)
41
7.7.8
Suction filter - check valve combination
42
7.7.9
Controller
43
7.7.10
Fittings
43
7.7.11
Safety devices
44
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015 5
7.7.12 Monitoring devices 45
7.7.13
Components installed by the client
45
7.8
General functional description
45
7.9
Refrigerant circuit
45
7.10
Oil System
46
7.10.1
Oil separation
46
7.10.2
Oil heater
46
7.10.3
Oil cooling
46
7.10.4
Oil filter
46
7.10.5
Oil pump
46
7.10.6
Oil injection
47
7.10.7
Oil circuit, OMC block
47
7.11
Capacity control
47
7.12
Technical specifications
47
7.12.1
Designed for use in explosive atmospheres!
47
7.12.2
Basic terms
48
7.12.3
Operating media
48
7.12.3.1
Refrigerant
48
7.12.3.2
Refrigeration machine oils
48
7.12.3.3
Secondary refrigerant
48
7.12.4
Operating limits
48
7.12.5
Water quality requirements, parameters
50
8
START-UP
53
8.1
Important information for start-up
53
8.2
Basics
54
8.3
Connecting the screw compressor package
54
8.3.1
Connecting the pipes
54
8.3.2
Electrical connection
55
8.4
Paint and insulation
55
8.5
Start-up procedure
55
8.5.1
Checking the electrical connection
55
8.5.2
Leak test
55
8.5.3
Drying, vacuum
56
8.5.4
Operating position of valves
57
8.5.5
Oil charge
60
8.5.5.1
Pressure compensation with the cooling system
60
8.5.5.2
Checking the direction of rotation of the oil pump motor
60
8.5.6
Checking the fault monitoring
61
8.5.7
Checking of the safety pressure limiter
61
8.5.8
Checking of the emergency-OFF button.
61
8.5.9
Adjustment of oil pressure
62
8.5.10
Checking the direction of rotation of the drive motor
62
8.5.11
Mounting the coupling
62
8.5.12
Checking the water circuits
63
8.5.13
Initial start-up
63
8.5.14
Checking the adjustment of the control slide
63
8.5.15
Checking the control slide adjustment times
63
8.5.16
Checking the oil cooler
63
8.5.17
Adjusting the amount of injection oil and the oil temperature
63
8.5.17.1
Screw compressor packages without refrigerant injection
64
8.5.17.2
Compressor units with refrigerant injection
64
8.6
Start-up after long standstill periods
64
8.7
Restarting after approx. 1 year standstill
64
9
USE, OPERATION, CONTROL
65
9.1
Use in explosive atmospheres, installation zones 1 and 2
65
9.2
Important information for the operator
65
9.3
Prerequisite for switching on
65
9.3.1
Overview of the operating modes
67
9.3.2
Setting of setpoint and limiting values as well as safety devices
69
9.4
Operation of the screw compressor package
69
9.5
Instructions regarding failures, their causes and remedies
69
10
CLEANING, MAINTENANCE, REPAIR
72
10.1
Use in explosive atmospheres, installation zones 1 and 2
72
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
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10.2 Important information for service personnel 72
10.3
Cleaning the heat exchanger
72
10.3.1
Mechanical cleaning
73
10.3.2
Chemical cleaning
73
10.4
Maintenance
73
10.4.1
General instructions
73
10.4.2
Repair work
74
10.4.2.1
Repair information
74
10.4.2.2
Repairs of pressure vessels subject to approval inspection
74
10.4.3
Maintenance intervals
74
10.4.4
Maintenance work
74
10.4.4.1
Maintenance of the screw compressor
74
10.4.4.2
Changing the block mounting filter element
75
10.4.4.3
Replacing the oil filter
75
10.4.4.4
Maintenance of the suction filter
76
10.4.4.5
Oil draining, oil filling, oil change
76
10.4.4.6
Oil pump maintenance
78
10.4.4.7
Changing the fine oil separation cartridges
78
10.4.4.8
Tightening screw fastenings
79
10.4.4.9
Coupling maintenance
79
10.4.4.10
Checking the function of check valves
79
10.4.4.11
Searching for leaks on the refrigerant side / leak test
79
10.4.4.12
Venting the refrigerant circuit
80
10.4.4.13
Refrigerant evacuation
80
10.4.4.14
Checking the bearing noise
81
10.4.4.15
Checking the solenoid valves for capacity control
81
10.4.4.16
Checking the oil heater
81
10.4.4.17
Maintenance of the compressor drive motor
81
10.4.4.18
Checking the start regime
81
10.4.4.19
Checking the safety devices
81
10.4.4.20
Checking the operating parameters
81
10.4.4.21
Maintenance of the switching cabinet
82
10.4.4.22
Checking the earth connection
83
10.4.4.23
Insulation
83
10.4.4.24
Check of the tightening torque on the adjusting elements of the fixing base.
83
11
DECOMMISSIONING
84
11.1
Shut-down in the event of dangerous situations
84
11.2
Standstill for a period <48 hours
84
11.3
Standstill for a period >48 hours
84
11.4
Measures during shutdowns
84
11.4.1
Monthly measures during standstill
85
11.4.2
Four weeks before restarting
85
12
DECOMMISSIONING, DISPOSAL
86
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
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Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
8 GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015
TABLE OF FIGURES
fig. 1
CE mark
15
fig. 2
Designation of the lifting points
21
fig. 3
Stopper with shackle
22
fig. 4
Transportation with a wire rope hoist
22
fig. 5
transportation using crossbeam
23
fig. 6
Location of the product identification (type plate)
33
fig. 7
Type plate
33
fig. 8
Safety labels of the pressure and temperature sensors, heater
34
fig. 9
Label of the safety valve
34
fig. 10
Labels of the screwed connections
34
fig. 11
Labels of the pipelines
35
fig. 12
Marking the direction of rotation of the compressor drive motor
35
fig. 13
Marking the direction of rotation of the oil pump motor
35
fig. 14
Labels of the pressure gauge
36
fig. 15
Test verification for the control system
36
fig. 16
Designation of the earth connection
37
fig. 17
Process flow diagram Grasso SP1, M-series
37
fig. 18
Main components of the GEA Grasso M-Series
38
fig. 19
GEA Grasso M-Series, arrangement of the SCP
39
fig. 20
GEA Grasso M-Series, arrangement of the compressor drive motor
39
fig. 21
GEA Grasso M-Series, arrangement of the coupling housing
40
fig. 22
GEA Grasso M-Series, arrangement of the oil separator
40
fig. 23
GEA Grasso M-Series, arrangement of the OMC block with oil filter system
41
fig. 24
GEA Grasso M-Series, arrangement of the oil cooler
41
fig. 25
GEA Grasso M-Series, arrangement of the (optional) oil pump
42
fig. 26
GEA Grasso M-Series, suction filter - check valve combination
42
fig. 27
GEA Grasso M-Series, arrangement of the controller
43
fig. 28
Corrosion resistance in presence of chlorides
51
fig. 29
Vacuum required to remove moisture from refrigerating plants
56
fig. 30
Stop valve open
57
fig. 31
Stop valve closed
57
fig. 32
Check valve
57
fig. 33
Shuttable check valve
57
fig. 34
Control valve
58
fig. 35
Shuttable check valve
58
fig. 36
Solenoid valve
58
fig. 37
Change-over valve
58
fig. 38
Oil pressure control valve
58
fig. 39
Overflow valve, safety valve
59
fig. 40
Pressure controlled check valve
59
fig. 41
Quick acting valve, spring-loaded
59
fig. 42
Charging valve, drain valve
59
fig. 43
Service valve
59
fig. 44
Oil temperature limiter
60
fig. 45
Temperature controlled control valve
60
fig. 46
Motor direction of rotation
62
fig. 47
Arrangement of MIN / MAX sight glasses
78
fig. 48
Operating position of the fine oil separation cartridges
79
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
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Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
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1 BASICS
1.1 Importance of the documentation
These operating instructions are part of the technical
documentation for the Grasso scope of delivery. It
contains advice for operating the package/chiller
safely, properly and economically. The observance
of the operating manual helps in avoiding dangers,
reducing repair costs and down-times and increasing
the reliability and durability of the package/chiller.
This operating manual is directed at the users of the
package/chiller and is specifically intended for the
operating company and its operating and maintenance personnel. This operating manual must be
read prior to transport, installation, commissioning,
maintenance, repair, disassembly/disposal.
All work explained in this operating manual must only
be carried out by technical personnel.
This operating manual must be supplemented with
instructions based on prevailing national regulations
regarding industrial safety, health protection and
environmental protection.
In addition to this operating manual and the mandatory accident prevention regulations applicable for
the respective place of installation, the accepted
technical regulations for safe work according to good
professional practices must also be observed.
The operating manual is a part of the total product.
The entire documentation, consisting of this operating manual as well as all supplied additional instructions, is to be always kept easily accessible at the
place of installation of the package/chiller. The complete set of documentation must also accompany the
package/chiller if it is sold.
1.2 Requirements for personnel, obligation to exercise due care
Qualification
All work explained in this manual (assembly, electrical connection, commissioning, operation, etc.) may
only be carried out by trained technical personnel
who observe the relevant technical regulations.
Technical personnel are representatives of the unit
manufacturer and persons who, as a result of their
technical training, experience and personal instruction in training measures, have sufficient knowledge
of:
–
applicable international and national standards,
–
applicable occupational safety regulations,
–
applicable accident prevention regulations,
–
applicable environmental protection regulations,
–
the construction and functioning of the unit,
–
recognised technical regulations for safe work
according to good professional practice.
The technical personnel must:
–
be able to assess the work assigned to them,
recognise and avoid possible dangers,
–
be authorised by those responsible for the safety
of the system to carry out the requisite work and
activities.
Caution!
No arbitrary changes may be made to
the control or other components
belonging to the unit. Maintenance
work may only be done by authorised
service staff.
Special requirements for the electrical technicians
Work on electrical components and modules may
only be carried out by an electrical technician
according to the rules relevant to electrical engineering. Furthermore the operator has to take care that
the electrical systems, tools and fixtures are operated according to the rules relevant to electrical engineering and applicable standards and serviced properly.
–
In principle it is prohibited to carry out work on
parts under voltage.
–
Fuses may only be replaced and not repaired or
bypassed.
–
Only the fuses specified in the electrical circuit
diagram may be used.
–
A two-pole voltage tester must be used to ensure
that the parts are de-energised.
–
The power supply as well as the unit casing must
be sufficiently grounded and tagged with a suitable label.
–
Deficiencies noticed in the electrical systems/
modules/tools and fixtures must be corrected
immediately. If an acute danger exists till then,
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
Basics
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the package/chiller must not be operated in the
defective condition.
Minimum age
The minimum age for the operation of the package/
chiller and installation is 18 years. All persons
involved in the assembly and installation of the package/chiller and the system must get themselves
trained at regular intervals and/or familiarise themselves with the current technical data of the device.
The training and instructions is to be conducted at
least once a year, unless some other interval has
been agreed upon with the manufacturer.
Obligation to exercise due care
The statutory regulations for meeting the obligation
to exercise due care are to be observed.
Meeting the obligation to exercise due care according to the current level of technology requires that
everything that is
–
technically possible (use of accepted technological rules) and
–
economically reasonable
be done to prevent damage in a protectively safe
manner.
1.3
Legal foundations (Germany)
The following standards, regulations, ordinances and
laws must be strictly observed to ensure the safety
and functional reliability of the packages and chillers:
–
EC Machinery Directive 2006/42/EC
–
EC Pressure Equipment Directive
2014/68/EC– AD 2000 Info Sheets
–
Hazardous Incident Ordinance (12. BlmSchV)
with 1st failure VwV
–
Federal Pollution Control Act (BImSchG), 4th
BimSchV
–
Water Resources Act (WHG), VawS
–
Hazardous Substances Ordinance (GefStoffV)
–
Recycling and Waste Management Act (KrWAbfG)
–
DIN EN 378, Part 1 to Part 4 Safety-related
technical requirements and environmental
requirements
–
Accident Prevention Regulation including
implementation regulations (BGR 500, chapter
2.35) on refrigeration plants, heat pumps and
cooling equipment (BGV B3) regarding noise
–
EN 12284 Refrigerant fittings, safety related
technical definitions, testing and marking
–
DIN 2405 Pipes in refrigeration plants, marking
–
VDMA specifications,in particular VDMA 24
243 and 24 020
–
VDI Guidelines
–
Instruction sheets for handling ammonia,
Instruction sheet for halogenated hydrocarbons containing fluorine BGI 648
–
Safety data sheet for ammonia and other refrigerants and refrigeration oils
The list of rules and standards has been taken from
Status Report No. 5 of the German Refrigeration and
Air Conditioning Engineering Association "Safety and
environmental protection in ammonia refrigeration
plants" and also fully applies to other refrigerants.
Danger!
The additional safety instructions as
defined in "Appendix E" must be
observed for packages for the designated use in potentially explosive
atmospheres, installation zones 1 and
2 in accordance with EN 60079-10.
The following:
–
standards,
–
safety regulations,
–
guidelines and recognised engineering practice,
listed in these operating instructions must be
observed at least!
Hint!
If the package/chiller is used in a
country other than Germany, the rules
and regulations applicable at the place
of installation must be observed and
complied with!
The mandatory accident prevention regulations
applicable for the respective country and area where
the product is used must also be observed.
Basics Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
12 GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015
Failure to observe the safety instructions can lead to
danger to personnel and the environment as well as
damage to the unit.
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
Basics
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1.4 Specified Use
Hint!
Observe the "Specified Use" chapter
of the installation instructions for the
screw compressor!
The screw compressor package must only be operated up to a maximum discharge pressure in accordance with the type plate.
It is imperative that you comply with the applicable
conditions of use with respect to pressure and temperature for the screw compressor package.
Do not change the setting values of the safety pressure switch. This would endanger the operating
safety of the refrigeration plant.
If the switch-off value is set higher than 0.9 x maximum operating pressure (see EN378-2) of the high
pressure section of the refrigerating system, this may
result in the the tank within this section of the system
rupturing.
The operating regime stipulated by the manufacturer,
especially for the starting phase of the screw compressor package, must be observed.
Operating parameters must be monitored. Operating
parameters must not deviate from within the defined
limits.
The screw compressor package has been designed
and manufactured for a specific application under
defined conditions of use. Unauthorised structural
modifications are not permitted. We assume no liability for any resulting damage or injury. In the interest
of further development, GEA Refrigeration Germany
GmbH reserves the right to make technical modifications. The screw compressor package described
here corresponds to the state of the art at the time
this operating manual was published.
The manufacturer must be consulted in all cases as
to the permissibility of the modification if there is any
change of the application or the conditions of use.
Do not make any modifications to the screw compressor package and the compressor control system.
These may impair the safety and functionality of the
SCP. They will also void the guarantee.
The pressure equipment described here must not be
used for any purpose other than the purpose specified here. The units must only be installed by the
supplier/installer and not by the end user. If the pressure equipment is not used according to the regulations, the safe use of the equipment is not guaranteed. The supplier/installer or the operator – and not
the manufacturer – is responsible for all personal
injury and damage to property resulting from
improper use.
The pressure equipment is not designed for dynamic
loads. If there is a risk of lightning strikes, the pressure equipment must be earthed. The supplier/installer must record instructions for regular inspection of
the pressure equipment in his operating manual and
must specify the procedure to be followed by the end
user in the event of damage. In order to prevent
burns or frostbite, the pressure receptacle must not
be touched during operation. This can be prevented
by respective safety measures. Appropriate warning
signs must be affixed. Compressor units or systems
must be equipped with safety valves in accordance
with EN 378. The foundation must provide sufficient
rigidity.
The supplier/installer must carefully install the accessories for the pressure equipment. The pressure
equipment must not be damaged during installation
and must be painted after installation. The pressure
equipment must only be filled with the refrigerant
specified in the contract. The pressure units must be
installed in the compressor unit or the system in such
a way that vibrations or pulses cannot be transferred
to the pressure units. The contacts must be installed
with the power supply disconnected.
Specified use includes observance of this manual
and all supplied operating manuals as well as compliance with the maintenance and service intervals
and conditions stipulated therein.
Warranty claims and authorisation for operation
become void if the equipment is not used for its
specified purpose.
1.5
Warning against foreseeable abusive use
A package/chiller is said to have been abused, if
–
unauthorised refrigerants, fuels and lubricants
and secondary refrigerant materials are used.
Hint!
Observe specification for the project!
–
electrical components are wrongly connected.
Hint!
Watch voltage and frequency!
–
mechanical components are wrongly connected.
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Screw Compressor Packages
14 GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015
Hint!
Watch pressure and temperature!
–
the supporting, hanging and storage facilities are
misused.
–
control and regulation units including control system software are tampered with.
–
the driving power generated by the motor is used
for purposes other than the operation of the
respective compressors and pumps.
1.6 CE mark
By affixing the CE mark, the manufacturer confirms
the conformity of the product with the applicable EC
Directives and compliance with the principle requirements stipulated within them.
fig.1: CE mark
The CE mark is affixed to the nameplate.
The CE mark for products from GEA Refrigeration
Germany GmbH is provided as defined in the Pressure Equipment Directive, i.e. pressure equipment is
placed on the market with the required equipment
parts with safety function. This complete assembly is
subject to the Pressure Equipment Directive.
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Screw Compressor Packages
Basics
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2 MANUFACTURER INFORMATION
GEA Refrigeration Germany GmbH is a company
within GEA Refrigeration Technologies, the Refrigeration Technology Segment of the GEA Group and
provides its customers around the world with highquality components and services for refrigeration and
process technology applications.
Locations:
GEA Refrigeration Germany GmbH
Factory Berlin
Holzhauser Str. 165
13509 Berlin, Germany
Tel.: +49 30 43592-600
Fax: +49 30 43592-777
Web:
www.gea.com
E-Mail: refrigeration@gea.com
GEA Refrigeration Germany GmbH
Factory Halle
Berliner Straße 130
06258 Schkopau/ OT Döllnitz, Germany
Tel.: +49 345 78 236 - 0
Fax: +49 345 78 236 - 14
Web: www.gea.com
E-Mail: refrigeration@gea.com
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Screw Compressor Packages
16 GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015
3 CUSTOMER SERVICE
GEA Refrigeration Germany GmbH supplies products of high quality and reliability. In addition, the
manufacturer ensures continuous operation of the
refrigeration and process technology system and
provides exceptional service for the components
supplied.
3.1
Technical customer service department
Do you require support from the technical customer
service department? Specially trained, experienced
service technicians are available on call for you in
order to provide assistance in case of technical problems and to offer support in the framework of our
after-sales service.
24/7 Hotline:
the hotlines can reached around the clock on every
day of the week:
•
Wireless
+49 (0) 172 39 12 050
•
Landline, weekdays from 7 to 17 hours
+49 (30) 43 59 27 61
+49 (30) 43 59 27 62
•
Email:
Grasso-service@geagroup.com
outside of Germany, Austria and Switzerland please
contact:
•
local sales office
www.gearefrigeration.de
technical support for liquid chillers with reciprocating
compressors in Germany, Austria and Switzerland
•
24/7 Hotline
+49 (345) 78236 20
The specialists of our Technical Customer Service
department support you in installations, acceptances, maintenance, operating questions, on-site
inspections and repairs of our products.
3.2 Spare parts
GEA Refrigeration Germany GmbH has its own practical and rapidly working spare parts department to
supply the necessary spare parts worldwide. Necessary spare parts are shipped as quickly as possible.
In most cases, you will receive your spare parts
within 24 hours after placing the order.
You can contact us using the following hotlines:
•
Wireless, out of hours
+49 (0) 172 30 14 579
•
Landline, weekdays from 8 to 17 hour
+49 (30) 43 59 27 50
•
Fax
+49 (30) 43 59 27 58
•
Email
Grasso-parts@geagroup.com
•
Order spare parts from our G-Pos. online
shop
(Grasso Parts online shop)
gea-refrigeration.de.spareparts@gea.com
3.3 Training courses
Warning!
All work on our systems must only be
carried out by technical personnel!
Acquire the technical know-how
required for this in good time!
Comprehensive training courses are held regularly
for service technicians and mechanics, thus ensuring
the safe and proper use and maintenance of our systems.
•
Email
Grasso-service@geagroup.com
3.4
Service contracts
It is possible to sign a long-term service agreement
(service contract). For further information regarding
the content, scope and conditions of the possible
service options, please contact the Technical Customer Service department.
•
Email:
Grasso-service@geagroup.com
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
Customer service
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4 SAFETY
4.1 General information for safety
The safety aspects to be observed for operating the
equipment are shown in the chapter on "Safety".
The equipment has been developed and manufactured according to the currently applicable state of
the art and is reliable in operation. It has been tested
and left the factory in a technically faultless safe condition.
In order to maintain this condition for the operation
time, the details of the project documentation and
certificates must be observed and complied with.
When operating the equipment, at least the general
safety regulations and the provisions and guidelines
referred to in this documentation must be observed.
Only compliance with all provisions and guidelines
will enable optimum protection of the personnel as
well as dangers to the environment and the safe and
smooth operation of the equipment.
4.2 Behaviour in the case of emergency
Hint!
Familiarise yourselves with the local
evacuation plan before beginning the
work.
Should an emergency situation arise despite adhering to the safety regulations, the package/chiller
must be shut down immediately and isolated from
the electrical mains.
The mains cable must be blocked in such a way it is
not possible to restart the unit accidentally and
marked as such.
The operator of the complete system has to take
care that an isolation device, e.g. a mains switch with
appropriate contact rating and an integrated indicator, is pre-installed in the mains cabling on site.
A separate mains cable/feed cable must be laid for
the operation of the package/chiller.
The mains cable/feed cable is to be specially protected and provided with an emergency stop switch.
4.3 Possible residual hazards
Warning!
Despite careful design of the machine
and implementation of all the safetyrelevant regulations, further risks for
persons and machine during all life
phases of the package/chiller cannot
be fully ruled out. The additional safety
instructions in the individual chapters
of this manual must therefore be carefully observed!
Residual risks that were ascertained during the risk
assessment carried out for the product according to
safety standard EN ISO 14121 - Safety of Machines
- are:
–
mechanical hazards due to sharp sheet metal
edges and projecting parts,
–
electrical hazards as a result of inadvertently
coming in contact with terminals and cables,
–
thermal hazards as a result of inadvertently coming in contact with heat exchangers and pipes,
–
exposure to noise,
–
hazards caused by vibration due to improper
installation,
–
hazards due to working materials and other
materials in case of allergies orthe like,
–
neglect of ergonomic principles,
–
combinations of various hazards,
–
unexpected start-up, unexpected rotation in case
of incorrect electrical connections or defects,
–
shut-down, emergency stop when defects are
detected,
–
changes to the rotational speed,
–
power failure,
–
failure of the control circuit or control loop,
–
incorrect assembly,
–
fracture during operation,
–
operating media or objects getting thrown out,
–
loss of stability and
–
personnel slipping, tripping or falling.
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Hint!
There are no radiation hazards
4.4 Installation in explosive atmospheres, installation zones 1 and 2
Danger!
The additional instructions for using
screw compressor packages in explosive atmospheres, installation zones 1
and 2, must be complied with!
Function and Design
The same functional and design characteristics apply
to the maintenance instructions for the use of screw
compressor packages in potentially explosive atmospheres as described in the respective applicable
operating manual.
In addition to this, the following extensions
apply:
–
All components relevant for the use of screw
compressor packages in relation to their use in
potentially explosive atmospheres (concerns
both electrical and non-electrical components)
are separately designed and documented! The
extended documentation scope (component
descriptions, certificates, calculations) is part of
the product documentation.
–
Extension to the method of working
The use of screw compressor packages is extended to use in potentially explosive atmospheres,
including the compression of process gases
(only compression for the purposes of pressure
increase). The screw compressor packages are
not suitable for pumping potentially explosive
mixtures. This means that, when the compressor
is in intake condition, the pumped liquid must not
contain any oxygen. The intake condition always
refers to pressure layers in the overpressure
range.
The owner operator and the system builder must
use monitoring devices reflecting the respective
state of the art standards to positively monitor
and ensure this effect.
–
Safety equipment extension
If oil heaters are used in potentially explosive
atmospheres (see component specification),
additional, separate oil level monitoring is abso-
lutely necessary to ensure a minimum oil level
above the heating elements. To this end, a separate oil level switch is used in each use case
according to the necessary explosion protection
specification.
Operation
The same regulations apply in regard to the operating instructions for screw compressor packages in
potentially explosive atmospheres as described in
the applicable operating manual.
In addition to this, the following extensions
apply:
–
In addition, the legal safety regulations apply to
the people responsible for operating the screw
compressor package, and must be complied with
respect to the transport, assembly, operation and
maintenance and if necessary the replacement
of subassemblies, etc. in potentially explosive
atmospheres.
The owner operators regulations must also
always be observed – see also section: Safety
information for compressor, Appendix E, and for
package, Appendix E.
–
The electrical engineering regulations for installations in potentially explosive atmospheres ,
especially EN 60079-10, apply to the installation
and connection of electrical components. The
relevant prescribed cabling material must be
used.
–
The whole screw compressor package must be
earthed by the owner operator.
Maintenance
The same regulations apply to the maintenance of
screw compressor packages in potentially explosive
atmospheres as described in the respective applicable operating manual.
In addition to this, the following extensions
apply:
–
In addition, the legal safety regulations for the
installation of the screw compressor packages
apply to the people responsible for the maintenance of the screw compressor package with
respect to the maintenance of individual components or assemblies or their complete replacement in potentially explosive atmospheres.
–
The maintenance may only be carried out in
agreement/with the knowledge and release of
the owner operator.
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Screw Compressor Packages
Safety
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–
The maintenance and replacement regulations
resulting from the operating manual for the components must be conformed with.
–
Appropriate special tools approved for the potentially explosive atmosphere must be used.
–
Only original spare parts may be used. If original
spares are not used, the guarantee is invalidated
or the owner is liable in the event of damage.
–
Each maintenance inspection (see maintenance
book) must also include checking the secure fit
of the threaded connections for the coupling
safety hood.
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Screw Compressor Packages
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5 TRANSPORT, STORAGE
5.1 General instructions
Caution!
Adequate lighting must be ensured
during loading and unloading as well
as for storage in order to avoid injuries
and damage to property.
There is a danger of impacts and
stumbling due to protruding parts on
the equipment (e.g. valve caps). There
is also the danger of being cut on
sharp edges and surfaces. There is a
danger of crushing parts of the body
during the transport work. Personal
protective equipment (work clothing,
work books, gloves) must be worn
during all activities on the equipment.
Hint!
These operating instructions must be
read prior to transport, storage and
delivery to the installation site. It is
imperative to strictly observe the
instructions and information given!
All work explained in these operating
instructions must only be carried out
by qualified personnel.
5.2 Delivery
Shipment is made in the type of packing stipulated in
the order. The screw compressor package is generally supplied without packing.
The screw compressor package has an inert gas
filler in the refrigerant circuit.
Warning!
The compressor(s) of the screw compressor package is/are
not filled with
oil. The screw compressor package
must not be started, therefore, before
proper assembly and start-up.
5.3 Transport (crane transport)
Warning!
The screw compressor packages are
not intended for transport with a fork
lift truck!
Screw compressor packages are high-quality products, which must be handled with due care during
transport. Protect the equipment from impact and set
it down carefully.
When transported by crane, the screw compressor
package must have the same position as in operation (frame downwards!). Only use the lifting points
provided. The lifting points are marked!
fig.2: Designation of the lifting points
Caution!
It is forbidden to attach SCPs to fittings or pipes or at the eyebolts / lifting rings of the compressor, the electric motor, the tank or the switching
cabinet.
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Screw Compressor Packages
Transport, Storage
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Take special care not to attach the ropes near to
small nominal diameter pipes or insulation and to
damage them. Use spacers if necessary.
The lifting points are not arranged on one plane. The
ropes must be longer than 3 m. The height differences between individual lifting points must be compensated by suitable extensions.
Make suitable arrangements (timber or insulating
material) to avoid damage to the surface.
Shackles must be used.
fig.3: Stopper with shackle
fig.4: Transportation with a wire rope hoist
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fig.5: transportation using crossbeam
Danger!
Make certain there is no one under the
suspended load during transport with
the crane!
Position the screw compressor package on the
transport vehicle such that it is prevented from tilting
and falling. Load securing is preferably carried out by
lashing to the specified points. The pipes and equipment of the screw compressor package must not be
entered. Components must be secured against
vibrations. The competent staff member or the company itself is responsible for ensuring safety during
transport.
Warning!
Screw compressor packages must be
adequately protected from external
influences during transport.
Transport packaging (optional): foil
The foil may only be removed before erecting the
screw compressor package at the intended installation location in the machine room. Up until this point
in time, the foil serves to protect the screw compressor package against external influences.
5.4 Bearings
When the screw compressor packages are delivered, check for possible transport damage and report
any damage to the manufacturer in writing.
The storage area of screw compressor units shall be
roofed, plain and paved and secured against access
of unauthorized persons. Place the screw compressor package onto timber planks and have it protected
from jerks or impacts.
Warning!
Screw compressor packages must be
adequately protected from external
influences (humidity, frost, extreme
heat) during storage. This usually concerns lengthy standing times outdoors
before installation and start-up of the
refrigeration plant. The manufacturer
recommends the use of plastic sheeting to cover the whole product.
The venting slits of the electric motors
must always be covered!
Storage temperature: 5°C ... 40°C
The composition of the paint on the screw compressor package is designed for installation in the
machine room (inside installation). Contact with
water (including water spray) must be avoided.
Warning!
The screw compressor package is filled with dry gas (e.g. nitrogen) before
delivery which prevents any change of
the properties of any already filled
operating medium (e.h. refrigerating
machine oil). Check the gas filling
once a week and recharge to the
specified overpressure if required.
Turn the shaft of the compressor at least every four
weeks (approx. 10 revolutions).
The transport packing (foil if present), that needs to
be opened for turning the compressor shaft and for
checking the gas filling, must be closed again after
carrying out the activities in order to ensure protection against external influences. The packing (foil if
present) must be replaced as needed and for lengthy
storage times.
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
Transport, Storage
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Warning!
Regular ventilation of the screw compressor package packaging (if
present) must be ensured in order to
prevent condensation on the surfaces
of the machine.
Long-term storage
With a standstill of the compressor of more than 16
weeks prior to start-up, there is a danger that the
shaft seal may stick on the shaft and therefore be
damaged on start-up. Because of this, removal and
cleaning of the shaft seal is mandatory in order to
ensure that it functions correctly.
1.
Use two pressure screws to remove the cover of
the shaft seal, including the stationary gasket
inserted in it.
2.
Removal of the seal package arranged on the
shaft with the associated slide ring by hand or, if
tightly seated, extraction by means of an appliance. If the seating is loose, the seal package
may adhere to the stationary seal and will be
pulled out when removing the cover.
3.
Clean the shaft seat with a lint-free cloth. Grease
it lightly and push the sealing package back onto
the shaft again.
4.
After pushing onto the shaft, the seal package
must be manually compressed against the spring
pressure which acts on it. At the same time, it
must be checked whether the gasket springs out
again.
5.
Then re-fit the cover of the shaft seal.
Warning!
Danger of cuts and crushing injuries.
6.
If storage is longer than 26 weeks, all O-rings
must be renewed.
5.5 Storage (several years)
Hint!
The instructions in the "Transport,
storage" chapter must be heeded.
The following storage conditions must be maintained
when storing screw compressor packages that are
equipped with a control.
1.
Storage temperature > 10°C
2.
Air humidity < 50%
If the screw compressor package is intended to be
stored, the following preparatory measures must be
carried out ex-works (especially protection against
internal and external corrosion):
•
All process connections on the screw compressor package are sealed tight.
•
The screw compressor package is charged with
dry gas to 1 bar.
•
A suction pressure gauge has been installed.
•
The facing sides of the mounted coupling hubs
have been greased. (Does not apply to sliding
bearing compressor drive motors)
Hint!
In case of the use of high-voltage
motors: the operating manual of the
manufacturer is to be followed, especially regarding any anti-condensation
heater required.
•
Free-standing motor and main flow shafts have
been conserved.
•
The space on the screw compressor for the shaft
seal has been greased.
•
The connections on the oil cooler water side
have been sealed.
The following maintenance work must be carried out
at the storage location during storage:
1.
Visual inspection of the general condition of the
screw compressor package.
2.
Cyclical rotation of the screw compressor shaft
(about 10 revolutions per month and the compressor drive motor (see operating manual).
Hint!
Does not apply to sliding bearing compressor drive motors.
3.
Check the transport fill pressure with a pressure
gauge at the connection of item 405 (see P+I
flow chart). If this value < 1 bar, replenish dried
gas via the valve of item 85 (see P+I flow chat).
All valves are already opened at the factory for a
common pressure range.
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Caution!
After completion of the storage period
and prior to re-delivery, a general
review in the factory or a general
examination at the storage location,
performed by the technical customer
service technician of GEA Refrigeration Germany GmbH, is recommended.
Please pay attention to the information
in the "Start-up" chapter.
The general check includes changing
the O-ring on the compressor shaft
seal as well as replacing the shaft seal
of the oil pump.
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
Transport, Storage
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6 INSTALLATION
6.1 Basic information for installation
Caution!
During the installation, make sure that
substances escaping from leaks do
not reach into the soil, groundwater or
surface water. The applicable legal
regulations must be heeded at the
place of installation (e.g.for Germany:
German Federal Water Act WHG).
All foundation calculations, the selection of materials
and the soil analysis are the designer's or owner’s
responsibility.
A plan must be produced for proper and professional
assembly prior to the installation. The electrical and
operating media connections must be established. It
must be borne in mind that, in addition to the installation area of the screw compressor package, there
must be sufficient space available for the pipes as
well as for operating during maintenance activities.
Install the screw compressor package on a level surface. The difference from the horizontal must not be
more than 0.3 %. Provide enough space for maintenance work.
Under normal conditions, the screw compressor
package stands solidly on the installation surface
due to its own dead weight. We recommend that you
provide ribbed rubber plates for shock absorption
between the support surface and screw compressor
package feet or machine base frame.
If greater damping is required (installation on a floor
ceiling or on the roof), vibration dampers must be
provided. The appropriate type of vibration damper
must be determined and realised for this case. Also
decouple the secondary refrigerant lines using compensators when vibration absorbers are used.
The welding seams must be inspected in accordance
with the Pressure Equipment Directive after welding
work by the customer or operator on pipe line connections and flanges.
6.2
Rigid installation
The frame of the screw compressor unit/ liquid chiller
is placed on foundation bolts on a prepared foundation. The frame must be levelled with suitable shims
such that the coarse alignment (radial and angular
misalignment ≤ 0.25 mm) at the coupling is attained
again. Then tighten the foundation bolts.
6.3 Anti-vibration mounting
The frame of the screw compressor unit must be
aligned with the levelling bolts until the coarse alignment (radial and angular misalignment (radial and
angle offset ≤ 0.25 mm) at the coupling is attained
again.
Before tightening the foundation bolts of the isolators, check that the isolators over the spring (predominantly made of rubber) are free and do not lie
on the foundation.
6.4 Electrical connection
Danger!
Contact with live components is prohibited.
Produce the earth connection according to the designation in the general
assembly drawing. See chapter "Designation of the earth connection".
Before starting work, make sure that all parts to be
connected are de-energised, e.g. by removing the
main fuse in all phases or installing a jumper wire.
The insulation resistance of the electrical tools and
fixtures and wiring is to be checked. The connection
may only be undertaken if this value lies in the allowable range.
All electrical connections must be established and all
electrical consumers/sensors must be connected
according to the circuit diagram.
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6.4.1 Use in explosive atmospheres,
installation zones 1 und 2
Danger!
The same regulations apply to the
operating instructions for screw compressor packages in potentially explosive atmospheres as described in the
respective applicable operating manual.
In addition to this, the following extensions apply:
1.
The relevant electrical engineering
regulations for installations in
potentially explosive atmospheres , especially EN 60079-10,
apply to the installation and connection of electrical components.
Relevant prescribed cabling material must be used.
2.
The whole screw compressor
package must be earthed by the
owner operator.
6.5 Sound insulation, weather protec-
tion
If the screw compressor package is intended for outdoor installation, it must be provided with a suitable
housing for sound insulation and weather protection
by the customer. The weather protection must provide the machine with adequate protection against
the climatic conditions at the installation location.
Hint!
The screw compressor package is not
intended for unprotected outdoor
installation. Protection against external influences, especially dirt, dust
and moisture (wetness), is essential.
The manufacturer will not accept liability for damage
due to incorrect outdoor installation.
6.6
Information regarding noise emissions
The noise information provides approximate parameters and apply to the installation without any secondary noise protection measures.
The information has a tolerance of ±3 dB.
The precise data depend closely on the emission
values for the motors, which are manufacturer
dependent.
Should local conditions require adherence to noise
levels, a calculation should be made using the specific motor data in individual cases.
Sound insulation measures, such as motor encapsulation or complete package encapsulation can achieve a significant reduction in sound level.
Wearing hearing protection with sufficient noise
reduction is recommended in rooms with running
screw compressor packages.
Caution!
According to EU Directive 2003/10/EC,
the allowable exposure limit value
regarding the daily noise exposure
level is 80 db(A). In the event of noise
levels above this limit value the system operator must provide the operator with information on exposure to
noise and personal hearing protection
and ensure that this is also worn
(2003/10/EC Article 6).
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Installation
GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015 27
Sound power level LWA in dB(A)
Compressor drive motor
output in kW
Compressor type/theoretical throughput volume in m3/h at 4500 RPM
H
721
L
833
M
1056
N
1316
55
Max 103 103 103 103
Min 96 96 96 96
75
Max 104 104 104 104
Min 97 97 97 97
90
Max 105 105 105 105
Min 98 98 98 98
110
Max 106 106 106 106
Min 99 99 99 99
132
Max 107 107 107 107
Min 100 100 100 100
160
Max 108 108 108 108
Min 101 101 101 101
200
Max 109 109 109 109
Min 102 102 102 102
250
Max
110 110
Min
103 103
315
Max
111
Min
103
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7 DESCRIPTION OF DESIGN AND FUNCTION
7.1 Installation in explosive atmospheres, installation zones 1 und 2
Danger!
The same functional and design characteristics apply to the maintenance instructions for the
use of SCPs in potentially explosive atmospheres as described in the respective applicable
operating manual.
In addition to this, the following extensions apply:
1.
All components relevant for the use of SCPs in relation to their use in potentially explosive
atmospheres (concerns both electrical and non-electrical components) are separately
designed and documented – see product description!
2.
Extension to the method of working
The use of SCPs is extended to use in potentially explosive atmospheres, including the
compression of process gases (only compression for the purposes of pressure increase).
The SCPs are not suitable for pumping potentially explosive mixtures. This means, when
the compressor is in intake condition, the pumped liquid must not contain any oxygen.
The intake condition always refers to pressure layers in the overpressure range.
The owner operator and the system builder must use monitoring devices reflecting the
respective state of the art standards, to positively monitor and ensure this effect.
3.
Safety equipment extension
If oil heaters are used in potentially explosive atmospheres (see also component specifi-
cations in the product description) additional, separate oil level monitoring is absolutely
necessary to ensure a minimum oil level above the heating elements. To this end, a separate oil level switch is used in each use case according to the necessary explosion protection specifications – see also the component specifications in the product description.
Operating Manual | GEA Grasso M-Series
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Description of Design and Function
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7.2 Product code of screw compressor packages - Grasso SP1, SP2, SPduo and M Series
X
Model size screw compressor package
The ND screw compressor will be provided for the screw compressor packages in the Grasso
SP2 series (two-stage).
Y Versions of the screw compressor package
9 Screw compressor version variations
A Oil cooling
(X1)
Screw compressor size HP side
Only for screw compressor packages in the Grasso SP2 series (two-stage).
X / (X1) Screw compressor package size
Code letter Theoretical volume flow
at 2940 min-1 in m³/h
Code letter Theoretical volume flow
at 2940 min-1 in m³/h
C 231
T 1460
D 265
V 1740
E 321
W 1940
G 372
Y 2390
H 471
Z 2748
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Code letter Theoretical volume flow
at 2940 min-1 in m³/h
Code letter Theoretical volume flow
at 2940 min-1 in m³/h
L 544
XA 3250
M 690 / 708
XB 4150
N 860 / 870
XC 4900
P 805
XD 5800
R 1040
XE 7170
S 1290
XF 8560
* Grasso M Series
Y Screw compressor package version
Design type
Screw compressor package
Refrigerant
NH
3
Refrigerant
R22
HFC
Refrigerant
Refrigerant
R290 and
R600a
CO2 and
Special
media
Horizontal oil separator installed below A H R F O
Oil separator installed vertically B K S G P
Oil separator horizontally in series C L T
Grasso SPduo/ mechanical suspension D M V Y W
Grasso SP2 (two-phase) E N U
9 Screw compressor versions
1 Standard refrigerating compressor Vi = 1.8; 2.0; 2.2; 2.6; 3.0
2 Standard refrigerating compressor Vi = 3.6
3 Standard refrigerating compressor Vi = 4.8
4 Standard refrigerating compressor Vi = 5.5
5 Standard refrigerating compressor Vi = variable
6 Booster Vi = fixed
7 Heat pump compressor Vi = fixed or variable
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Screw Compressor Packages
Description of Design and Function
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8 -- --
9 Speed regulated Vi = variable
A Oil cooling
Code letter Oil cooling
A Water-cooled oil cooler
B Refrigerant cooled oil cooler
C Refrigerant injection
D Water and refrigerant cooled oil cooler
E Water or refrigerant cooled oil cooler and refrigerant injection
F Without oil cooler
Examples of designation
XA B - 6 A Singe stage screw compressor package Grasso SP1 with screw compressor 3250 m³/h
(XA), refrigerant NH3 and vertically installed oil separator (B), booster with fixed internal volume ratio (6)with oil fine separation and water-cooled oil cooler (A)
T A - 2 A Singe stage screw compressor package Grasso SP1 or SSP1 with screw compressor 1460
m³/h (T), refrigerant NH3 and horizontally installed oil separator (A), fixed internal volume
ratio Vi = 3.6 (2)
with oil fine separation and water-cooled oil cooler (A)
N A - 3 B Screw compressor package Grasso M with screw compressor 873 m³/h (N), refrigerant NH
3
and horizontally installed oil separator (A), fixed internal volume ratio Vi = 4.8 (3)with oil fine
separation and refrigerant-cooled oil cooler (A)
LD - 2 A Screw compressor package Grasso SPduo with 2 of screw compressors 544 m³/h (L),
refrigerant NH3 and DuoPack version or multiple configuration (D), fixed internal volume
ratio Vi = 3.6 (2) with oil fine separation and water-cooled oil cooler (A)
W E - 6 A (L) Two-stage screw compressor package with LP screw compressor 1940 m³/h (W), refriger-
ant NH3 two-stage package (E), LP-compressor as booster (6), with oil fine separation and
water-cooled oil cooler (A), HP-compressor 544 m³/h (L)
7.3 Technical specifications
Packages / chillers are designed and manufactured
for special fields of application. For technical specifications see the following.
–
order specification,
–
list of parameters,
–
general assembly drawing,
–
P+I diagram.
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7.4 Location of the product identification
(name plate)
The type plate contains the most important technical
data pertaining to the product. This data and the contractual agreements define the limits of designated
use.
As standard, the type plate is fixed to the oil separator (deviations of the location are possible).
fig.6: Location of the product identification (type plate)
fig.7: Type plate
GEA Refrigeration
Germany GmbH
Contact data of the manufacturer
Type: Type designation of the screw
compressor package
Serial no.: Serial number of the screw
compressor package
Year of construction:
Year of construction of the
screw compressor package
Weight without filling:
Weight of the screw compressor package when empty
Refrigerant: Information regarding the
refrigerant used
Max. operating
pressure:
Information regarding the
max. operating pressure
Volume flow:
Information regarding the volume flow
The default languages are English and German
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Screw Compressor Packages
Description of Design and Function
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7.5 Information and safety labels on the
product
Danger!
The safety-related labels on the package/chiller must be followed!
7.5.1 Labelling of the pressure and
temperature sensors, heater
(safety labels)
fig.8: Safety labels of the pressure and temperature sensors,
heater
Importance of the labels:
Before replacing pressure and temperature sensors
without dip tube, it must be ensured that the pipes
into which the sensors are mounted are not pressurised. The pressure-free state can be achieved by
closing the shut-off valves before the sensor to be
replaced.
Before replacing oil heater it must be ensured that
the oil separator into which the oil heater is screwed
in is not pressurised.
Hint!
Not applicable to oil heaters of the
HLP type series.
7.5.2 Label of the safety valve
(safety labels)
fig.9: Label of the safety valve
Importance of the labels
The safety valve must be connected to a blow-off
line.
7.5.3
Labels of the screwed connections with DiNova ring
(handling instructions)
fig.10: Labels of the screwed connections
The informative label for all screwed connections
with DiNova ring (handling instructions) is attached
to the electric motor in a clearly visible manner.
Importance of the labels:
If any leakage occurs at a screwed connection
(escaping gases or vapours), the screwed connection must be tightened:
Counter-hold the screwed pipe connection using
a wrench. Tighten the pipe nut about 1/4 to 1/
3
rotation beyond the point where the increase in
the force if felt.
®
The leakage is remedied.
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7.5.4 Labels of the pipelines
(information plate)
Pipelines in refrigeration plants must be labelled as
follows (DIN 2405):
–
Refrigerant
–
Direction of flow
–
State of phase
fig.11: Labels of the pipelines
1 Arrow head (indication of the direction of flow)
2 Horizontal stripe (indication of the state of
phase), green = liquid // blue = gaseous cold //
red = gaseous hot
3 Information field (label of the refrigerant)
7.5.5 Marking the direction of rotation
of the compressor drive motor
(information plate)
fig.12: Marking the direction of rotation of the compressor drive
motor
The direction of arrow indicates the direction of rotation of the compressor drive motor
7.5.6
Marking the direction of rotation
of the oil pump motor
(information plate)
fig.13: Marking the direction of rotation of the oil pump motor
The direction of arrow indicates the direction of rotation of the oil pump motor
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Screw Compressor Packages
Description of Design and Function
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7.5.7 Labels of the pressure gauge
(information plate)
fig.14: Labels of the pressure gauge
1 Description of the pressure gauge measuring
point
The description of the pressure gauge measuring
point is attached directly underneath the pressure
gauge. The gauge board can be arranged horizontally as well as vertically.
7.5.8 Labeling of the control / control
cabinet
(information plate)
•
Label on the rear side of the control unit of the
control system (visible after opening the switching cabinet):
–
Project name
–
Make number of the package/chiller
–
MPI address
•
Label on the inside of the switching cabinet:
–
Test verification for the control system
fig.15: Test verification for the control system
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36 GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015
7.5.9 Designation of the earth connection
Safety labels
fig.16: Designation of the earth connection
Importance of the labels
Ensure that the product is properly grounded before
start-up. Connect the earth connection. The necessary mounting hardware and cables are not included
in scope of supply.
See general assembly drawing for the position of the
earth connections.
Hint!
The cross-section of the ground wire
must be at least 10 mm². Alternatively,
two separately installed and separately
connected ground wire must be used,
ensuring the minimum cross-section
in the sum.
7.6 Process flow diagram
fig.17: Process flow diagram Grasso SP1, M-series
1 Suction side
2 Compressor
3 Oil separator
4 Pressure side
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
Description of Design and Function
GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015 37
7.7 Main components
Screw compressor packages within the Grasso M-series series consist of the following main assemblies and
components:
fig.18: Main components of the GEA Grasso M-Series
Hint!
The documentation of
the main components is
part of the product documentation (see product
description or operating
manuals of the supplier,
e.g. for the compressor
drive motor).
10 Screw compressor See installation instructions for the screw com-
pressor
15 Compressor drive motor See operating manual of the compressor drive
motor
20 Oil separator See component documentation
25 OMC block (possible as separate oil filter for greater amounts of oil) See component documentation
30 * Oil cooler See component documentation
40 * Oil pump (possible as an external oil pump for booster) See component documentation
45 ** Suction filter See component documentation
55 ** Check valve - suction side See component documentation
60 Check valve - pressure side See component documentation
95 Coupling housing See component documentation
180 Controller See control unit documentation
360 * Oil heater See component documentation
Safety devices See component documentation
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Screw Compressor Packages
38 GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015
* not shown in the picture
** integrated into the screw compressor
7.7.1 Screw compressor
fig.19: GEA Grasso M-Series, arrangement of the SCP
The screw compressors are characterised by a compact design, high reliability, high quality components
and ease of maintenance.
Screw compressors are dual rotor positive displacement machines that run according to the displacement principle and operate by oil injection.
Screw compressors are operated with refrigerant
(standard: ammonia NH3, other refrigerants upon
request). For the refrigerant, refrigerating machine oil
is chosen in accordance with lubricating oil information for screw compressors.
Various series and sizes of screw compressors are
available for different fields of application.
The screw compressors are driven directly by the
compressor drive motor via a flexible coupling.
Hint!
The documentation of the screw compressor (installation instructions, part
lists, drawings) is an integral product
documentation.
7.7.2 Compressor drive motor
fig.20: GEA Grasso M-Series, arrangement of the compressor
drive motor
Standard: The compressors are driven via a coupling by means of an air-cooled 2-pole IP23 electric
motor with an operating voltage of 400 V; 50 Hz.
Option: Other protection classes, operating voltages
and frequencies as well as speed-controlled motors
are available on request.
Hint!
The documentation of the electric
motor (operating manual) is an integral
part of the product documentation.
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Screw Compressor Packages
Description of Design and Function
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7.7.3 Compressor with coupling housing
fig.21: GEA Grasso M-Series, arrangement of the coupling
housing
The coupling housing contains the coupling and is
used for the attachment of the compressor drive
motor. The elastic design of the coupling brings
about the neutralisation of otherwise disturbing influences such as axial or radial forces, vibrations or offset.
Speed fluctuations and speed shocks are damped
and cushioned, torsional vibrations are reduced.
Hint!
The documentation of the coupling is
a part of the product documentation.
7.7.4 Oil separator
fig.22: GEA Grasso M-Series, arrangement of the oil separator
The design of the oil separators is standardised and
features reduced oil carry-over and low oil consumption.
The oil separator is installed horizontally.
Hint!
The documentation of the oil separator
(operating and maintenance instruction, acceptance certificate) is a integral part of the product documentation.
Oil heater
Electric oil heaters are built into the oil separator to
heat the oil refrigerant mixture in the oil separator
during the standstill of the screw compressor package. The oil heater prevents condensation of the
refrigerant into the oil and, thus, any foaming of the
oil during start-up.
Oil heaters are equipped with:
–
Temperature controller for protection against
overheating
(Switching temperature 110°C)
–
Temperature limiter in case of faults, e.g. protection against dry running
(permanently set to 150°C)
The oil heater is switched on when the screw compressor package is stopped and is switched off automatically on starting. A manual switch-off for long
standstill periods is recommended.
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40 GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015
Hint!
The documentation of the oil heater
(operating and maintenance instruction, acceptance certificate) is a part of
the product documentation.
7.7.5 OMC block with oil filter system
fig.23: GEA Grasso M-Series, arrangement of the OMC block
with oil filter system
The OMC block contains the oil distributor system in
the oil circuit. Necessary control and shutoff fittings
are integrated in the OMC-block. Connections for
temperature and pressure sensors as well as service
ports are present. The OMC block is combined with
a standardised filter system and oil pump unit and
forms the central control and regulation unit within
the oil circuit.
Optionally, the OMC-block can be equipped with a 3way valve element (for ensuring a minimum oil temperature when starting the compressor).
Hint!
The documentation for the OMC block
(operating manual, acceptance certificate) is an integral part of the product
documentation.
7.7.6 Oil cooler
fig.24: GEA Grasso M-Series, arrangement of the oil cooler
The oil cooler is used for cooling the oil heated in the
compressor in order to ensure sufficient oil viscosity
for supplying to the compressor.
Hint!
The documentation of the oil cooler
(operating manual, acceptance certificate) is an integral part of the product
documentation.
7.7.7 Oil pump (optional)
Special design for minor pressure differences
(booster)
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GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015 41
fig.25: GEA Grasso M-Series, arrangement of the (optional) oil
pump
The oil pump is an important component of the oil
circuit. It is used for pumping and distributing refrigerating machine oil.
The oil pump ensures that the oil is distributed to the
individual lubrication points (e.g. journal bearing, balance piston and packing gland of the compressor).
Hint!
The documentation of the oil pump
(operating manual, acceptance certificate) is an integral part of the product
documentation.
7.7.8 Suction filter - check valve combination
fig.26: GEA Grasso M-Series, suction filter - check valve com-
bination
The suction filter - check valve combination contributes substantially to the high working reliability of the
components and the overall product.
The suction filter - check valve combination prevents
dirt particles carried by the suction flow from entering
into the screw compressor.
Hint!
The documentation of suction filter check valve combination is an integral
part of the compressor documentation.
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Screw Compressor Packages
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7.7.9 Controller
fig.27: GEA Grasso M-Series, arrangement of the controller
The screw compressor package is equipped with a
GEA Omni™-type controller.
The GEA Omni consists of the control unit with operator keypad and display unit, indicator lights for
"Running", "Warning" and "Alarm", the emergency
stop button, the output relays and the casing.
The GEA Omni is mounted directly on the package
as standard. As an option, the GEA Omni can be
installed in a control centre.
The GEA Omni performs the following functions
as standard:
•
Display of all important physical and technical
parameters, e.g. Pressure, temperature, motor
current, capacity, number of operating hours,
operating mode and status signals
•
Automatic start up and shut down of the screw
compressor package and capacity control
dependent on the suction pressure or an external temperature,
•
Monitoring of all operating parameters
•
Compressor capacity limitation, in case the
measured discharge pressure, suction pressure,
secondary refrigerant temperature or motor current indicate overload
•
Fault memory with date and time
•
Wire failure detection for all analogue input signals
•
Password protection for preventing unauthorised
access to important parameters
•
Non-volatile saving of program
•
Possibility of communication with master controller via MPI
(optionally via Profibus-DP, Modbus RTU or
Modbus TCP)
Hint!
The documentation of the controller
(operating manual, circuit diagram,
parameter list, communication guideline) forms part of the product documentation.
7.7.10 Fittings
The term fitting generally designates a control element of the machine. Among other things, the term
fitting is also used for valves if these are used for the
control and regulation of fluid flows in the piping.
Furthermore, all kinds of installations in piping, such
as sight glasses, measurement apertures, filters and
similar are also designated as fittings. Therefore, fittings also include all kinds of valves, such as:
–
Stop valves
–
Check valves
–
Safety valves
–
Throttle valves
Each fitting has its own field of use, according to the
pressure or temperature in the pipe, the size of the
pipe, the sealing requirements for the fitting, the
reduction and direction of the flow of liquid as well as
the medium itself.
The safety fittings are used to limit the pressure in
systems which are under pressure.
Each fitting is designed for the specific application.
The fittings can be operated manually or by motor,by
gear motors, or pneumatic or hydraulic cylinders, for
example. In reset fittings, the flow of fluid in the pipe
causes automatic closing of the valve.
Depending on the model, different closing elements
(e.g.valve discs, flaps, pushers) close the pipe connected to the fitting.
Hint!
The documentation of the fittings
(acceptance certificates) forms part of
the product documentation.
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Screw Compressor Packages
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7.7.11 Safety devices
The following safety devices are fitted onto the SCPs
of the GEA Grasso M-series type series:
Drive motor safety devices
Rated current limitation (016)
The rated current limitation is realised by the compressor control system: When the rated motor current is exceeded, the control slide of the compressor
is driven in the MIN direction until the motor current
reaches a permissible level. The normal output control then comes back into force.
Thermistor (017)
The thermistor shuts down the compressor drive
motor when the temperature of the compressor drive
motor windings exceeds the allowable value.
Pressure-controlled check valve integrated into
the compressor (055)
The check valve function prevents pressure equalisation with the LP side of the plant and simultaneous
prevents a reverse rotation of the screw compressor.
Check valve - pressure side (060)
The pressure side check valve prevents refrigerant
from re-condensing in the oil separator.
Oil pressure regulating valve (075)
The oil pressure control valve regulates the differential pressure between the oil pump discharge side
and the discharge pressure of the package. The oil
pressure control valve is integrated into the OMCblock (oil management centre).
Safety device to prevent the discharge pressure
from being exceeded
(pressure transducer 105)
The compressor control system switches off the
screw compressor package when the specified limit
value has been exceeded.
Limit value = see parameter list
Safety device to prevent the differential pressure
between the oil pressure after oil pump (pressure
transducer 110) and the discharge pressure
(pressure transducer 105) oil circuit monitoring
from falling too low
The compressor control system switches off the
screw compressor package when the pressure difference between oil pressure after oil pump and discharge pressure falls below the specified limit value
after a delay period.
Limit value = see parameter list
Safety device to prevent the discharge temperature from being exceeded (resistance thermometer 120)
The compressor control system switches off the
screw compressor package when the specified limit
value has been exceeded.
Limit value = see parameter list
Safety device to prevent the oil temperature from
being exceeded (resistance thermometer 125)
The compressor control system switches off the
screw compressor package when the specified limit
value has been exceeded.
Limit value = see parameter list
The minimum oil viscosity for safe compressor operation is ≥ 7 cSt. In case of oils that are soluble in
refrigerant, the minimum oil viscosity is to be
ensured depending on the discharge pressure and
temperature, oil temperature, as well as the type of
oil.
Overflow valve (340)
The overflow valve protects the compressor against
impermissible high pressure. The overflow valve
(provided that delivered unassembled) must be connected with the suction pipe on site.
Triggering pressure = see parameter list and P+I
flow chart
The overflow valve is designed in accordance with
DIN EN 13136 "Refrigerating systems and heat
pumps - pressure relief devices and associated piping - methods for calculation".
Warning!
If not fitted on delivery, the overflow
valve must be connected to the suction side when installing the SCP in
the refrigeration plant!
Safety valve (345) on the oil separator
The safety valve protects the screw compressor
package against impermissible high pressure.
Triggering pressure =
see parameter list and P+I
flow chart
If the screw compressor package is installed into a
refrigeration system comprising an emergency blowoff station, only the oil separator connection is used.
The valve is available as an option, depending on
the required acceptance.
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44 GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015
The safety valve is designed in accordance with DIN
EN 13136 "Refrigerating systems and heat pumps pressure relief devices and associated piping - methods for calculation".
Safety pressure limiter (350)
Safety pressure limiter with two separate trigger contacts, one of which can only be reset using a tool.
The safety pressure limiter switches off the compressor drive motor if the discharge pressure rises above
the set point.
Switching off pressure 1 = see parameter list
Switching off pressure 2 = see parameter list
If it cannot be ruled out that the liquid refrigerant
might attain more than 90% of the oil separator’s volume, then the customer must install an additional
safety valve to prevent expansion of the liquid in the
oil separator (design in accordance with DIN EN
13136, arranged according to EN 378-2 Annex F).
7.7.12
Monitoring devices
The following operating values will be continually
monitored in a standard screw compressor package:
–
Suction pressure
–
Discharge pressure
–
Oil pressure oil circuit monitoring
–
Suction temperature
–
Discharge temperature
–
Oil temperature
–
absolute primary slide position
–
Motor current
–
Suction pressure saturation temperature
–
Saturation temperature
of condensing pressure
–
Number of running hours
–
Difference between oil and discharge pressures
(oil circuit monitoring)
–
Set point of controled value in °C
–
Real point of controled value in °C
–
Internal volume ratio
–
Used refrigerant
–
Controled value
–
Used options
–
Oil pressure after oil filter - optional -
–
Differential pressure of oil pressure after oil filter
and discharge pressure (oil filter monitoring) optional -
7.7.13 Components installed by the client
Warning!
The components and parts the customer installs in particular the secondary refrigerant and cooling medium
circuits as well as the oil circuit need
to made from materials suitable for the
fluids flowing through them. Furthermore, in the event of modifications to
the product by the customer, the
effects on the safety devices are to be
checked.
GEA Refrigeration Germany GmbH
does not assume any liability for damage arising and the violation of the
safety regulations which result from
the use of unsuitable materials or
through modification to the product
which is not considered in the original
safety concept.
7.8 General functional description
Screw compressor packages are refrigeration system components and serve to compress refrigerants
such as ammonia (or other operating media on
request).
Operation as a heat pump is also possible.
7.9 Refrigerant circuit
The screw compressor draws in refrigerant vapour
via the suction check valve and suction filter and
then discharges the compressed vapour into the
plant via the oil separator and discharge check valve.
The suction-side check valve prevents a sudden
pressure equalisation with the low pressure side of
the chiller, while also preventing reverse rotation of
the screw compressor.
The pressure side check valve prevents refrigerant
from re-condensing in the oil separator.
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GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015 45
Hint!
The discharge check valve can be integrated into the oil separator for screw
compressor packages with discharge
side nominal diameters up to NB 150.
The suction filter prevents dirt particles carried by the
suction flow from penetrating into the compressor.
The filter element is characterized by a very large filtering area. The filter fineness is 140
μm.
Gas vibrations which can arise in the pressure chamber of compressors under high pressure conditions
in the range of zero delivery are prevented by a gas
vibration protection system. This comprises a pressure compensation line between the oil separator
and the working chamber of the compressor.
7.10 Oil System
The screw compressors operate oil-flooded. During
the compression process, refrigerating machine oil is
supplied to the compressor for lubrication, sealing,
noise reduction, and absorption of part of the compression heat. After the compression process, the oil
is separated again from the refrigerant in the oil separator.
7.10.1 Oil separation
The refrigerant-oil mixture is led into the first part of
oil separator. The first part of the oil separator consists of two chambers. The first chamber employs
gravity separation. The hot gas passes the demister
while flowing out of the first chamber into the second
chamber. The oil separated thereby is collected in
the second chamber. Both the chambers of the first
part of oil separator simultaneously serve as oil
receivers.
In the second part of the oil separator, the fine separation of the aerosol oil portion from the refrigerant is
performed by means of replaceable fine oil separation cartridges. The oil separated in the fine separation part of the oil separator is returned to the compressor via an additional orifice.
7.10.2 Oil heater
The oil heater on the oil separator is to be started
when the package is shut down in order to ensure a
minimum oil temperature and sufficient oil viscosity
required for restarting the package. The oil heating is
not regulated. The maximum temperature of the
heating rod is restricted.
7.10.3 Oil cooling
Before it is returned to the compressor for use, the
oil heated up in the compressor has to be cooled
down to a temperature at which it has sufficient viscosity.
The following oil coolers are available:
1.
liquid-cooled (non corrosive media)
–
water (non corrosive)
–
propylene glycol (25%)
–
ethylene glycol (35%)
–
Other refrigerants on request
2.
Thermosiphon
3.
Refrigerant injection
7.10.4 Oil filter
After cooling, the oil enters the oil filter which retains
solid particles from the entire oil flow.
Due to its large surface, the star-folded glass fibre
element has a high absorbing capacity and thus a
long operating lifetime. The filter has a relative filter
fineness of 25 µm.
7.10.5 Oil pump
The oil pump runs for pre- and during compressor
operation.
It draws the refrigeration compressor oil from the
receiver space in the oil separator, through the the
oil cooler and oil filter and pumps it to the bearings,
the balance piston, the shaft seal, to the capacity
control system and, if fitted, to the compressor's
hydraulic Vi adjustment system.
The oil pump pumps more oil than the compressor
uses. This surplus quantity of oil is returned to pump
suction via the spring loaded oil pressure regulating
valve. The oil pressure regulating valve regulates a
pressure difference between the oil pump discharge
side and the unit final pressure (according to the
value in the P+I diagram).
Description of Design and Function Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
46 GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015
7.10.6 Oil injection
The injection oil is fed without a pump via the oil
injection regulating valve.
The oil injection control valve is used to adjust the
necessary compression discharge temperature.
The control valve is provided with a check function to
prevent sucking refrigerant through the oil pump.
7.10.7 Oil circuit, OMC block
An OMC-block (oil management block) is flanged on
to the oil filter as an oil distributor system. The oil
flow is distributed via the bore-holes and channels to
functional ranges of the screw compressor. All regulating valves and shut-off valves necessary for the
regulation of the oil circuit are integrated into the
block. As a result, a centralised control unit is available for the screw compressor package.
The oil filter with OMC-block (oil management block)
is fitted with an oil drain and refilling stop valve which
may be connected to a separate oil pump or
receiver.
Vent valves are fitted to oil filters for maintenance
and repair purposes.
The oil in oil filter may be drained for changing oil filter via a separate stop valve.
7.11 Capacity control
The screw compressors are fitted with a continuous
capacity control with a range of 10 -100%.
The capacity is adjusted by shortening the screw
compressor stroke. The defining factor for the compression process is the effective rotor length; this is
altered by a hydraulically operated control slide.
The position of the control slide is recorded by the
position sensor. Upon reaching the MIN or MAX end
position, it is signalled to the control device and the
relative control slide position can be displayed in percentage on the touch panel.
The hydraulic adjustment of the control slide is realised using solenoid valves, which are integrated into
a single block.
The control slide travel speeds in the MIN and MAX
directions should, to the extent possible, be the
same during operation to ensure better compressor
control.
7.12 Technical specifications
7.12.1 Designed for use in explosive
atmospheres!
Danger!
When operating the screw compressor
package in explosive atmospheres, the
special safety instructions for use in
explosive atmospheres that are mentioned in this operating manual must
be heeded.
Hint!
The screw compressor packages can
basically be used in explosive atmospheres.
Some specifics must be heeded when using the
screw compressor packages in explosive atmospheres of installation zones 1 and 2.
The basis for use in explosive atmospheres is the
following data of the operator:
–
Zone division as per EN 60079-10 (or other
equivalent international standards),
–
description of the atmosphere (required gas
groups),
–
required temperature class.
This data is stored in the request sheet for project
055 100A. The 055 100A request sheet is part of the
product documentation.
For using and placing a screw compressor package
into operation within the EU, the package is manufactured ATEX-compliant (see component selection,
protection systems, regulations, etc.)
The following marginal parameters generally apply:
–
The screw compressor packages can be installed in Zones 1 and 2 in accordance with EN
60079-10.
–
The max. achievable temperature class is T4.
–
The screw compressor packages are not suitable for carrying explosive mixtures; the suction
pressure of the package is always in the overpressure range.
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Description of Design and Function
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7.12.2 Basic terms
Refrigerant Materials circulating in a plant (liq-
uid or gas), which by means of
their change of state of the package withdraw heat from another
medium (cooling or heating agent)
or can dissipate heat to this
medium.
Secondary
refrigerant
Fluids that can absorb the heat of
a system and dissipate it to a
refrigerant (reversible process)
and are used for the cooling of a
system (industrial process)
Heating
agents
Media (liquid or air), which transport and emit the heat absorbed in
the secondary refrigerant. If water
is used as the heat carrier, the
terms warm water or cooling water
are also used.
7.12.3 Operating media
7.12.3.1
Refrigerant
The technical order specification defines the refrigerant used. All components of the screw compressor
package are designed for use with the defined refrigerant.
Hint!
The safety data sheet for the refrigerant used must be observed. The safety
data sheet is part of the product documentation.
7.12.3.2 Refrigeration machine oils
Caution!
In order to ensure an adequate loadbearing capacity of the sleeve bearings and to ensure the service life of
the roller bearings, a minimum viscos-
ity of 7cSt (=10-6 m²/s) upstream of the
compressor is required. A suitable oil
must be carefully selected in consideration of the operating conditions.
The selection criteria and selection
tables are summarised in the technical
information document entitled "Lubricant oils for screw compressors". This
technical information forms part of the
product documentation.
GEA Refrigeration Germany GmbH can
provide assistance in the selection of
a suitable refrigeration machine oil on
request.
7.12.3.3 Secondary refrigerant
•
Low corrosion water
•
Permitted brine levels: see Grasso Design Program
Hint!
For other secondary refrigerants, compatibility with the materials used must
be ensured.
7.12.4 Operating limits
The screw compressors can be operated under the
most varied operating conditions within the given limits of application according to the requirements
involved. The limits of application listed below for the
screw compressors are based on the operational
principle of the screw compressor and thermodynamic ratios and are based on practical operating
conditions and design. The tabulated data apply for
single, two-stage and heat pump operation. Depending on the compressor the manufacturer selected,
the specific operating conditions limitations may
occur within the parameters in the table.
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Hint!
For specific operations the selection
and evaluation will take place within
the manufacturer's compressor selection programme.
Caution!
To avoid "zero flow" in the compressor, which can damage the compressor, the minimum control slide position in the manufacturer's compressor
selection programme must be adhered
to.
"Minimal control slide position <value>
% accepted start."
If the value entered is "> 0", then a limitation of the control slide path must
be put in place in coordination with the
manufacturer. The path limitation can
be set created mechanically with a
stop sleeve or by installing virtual controls (virtual stop sleeve) on the compressor.
Maximum permitted pressure p bar g. max.
≤28 bar
or
≤52 bar
Pressure ratio p / p
0
π - min. > 1.5
Pressure difference (p - p0)
Δp bar min. > 0.8
Suction temperature t0 (compressor inlet) t
0h
°C min. > - 60
Discharge temperature (compressor outlet)
t
e
°C max. < 120
Compressor frame size
H L
M/N
*)
28 bar
M/N
*)
52 bar
max. Drive power (kW)
50 Hz
60 Hz
300
360
300
360
300
360
530
640
max. Nominal torque
**)
Nm 960 960 960 1700
max. permissible speed
min
-1
4500 4500 4500 4500
min. permissible speed
min
-1
1000 1000 1000 1000
*)
For type M/N, the compressor drive shaft ends are different for 28 bar and 52 bar versions.
**)
When running the compressor, the maximum torque falls by 25% as opposed to electrical drives.
Hint!
All of the following requirements must
be observed!
1.
Compressors for a discharge pressure up to 52
bar (currently not available) are equipped with
housings made of a material of higher strength
and are fitted with special components.
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2.
Minimum suction overheating in compressor
inlet: "wet" operation is not possible.
3.
For Δ p = p - po ≤ 2.9 bar an external oil pump to
be taken for compressor sizes H to N.
4.
For
π ≥ 8 gas vibration protection is required.
5.
For CO2 usage the use of a completely electrified oil pump for injection and function oil needs
to be checked in all types of compressors
depending on the operating conditions;
6.
The discharge temperature te must be 10 K
above the condensing temperature (te ≥ tc + 10
K).
7.
Due to the solubility of refrigerant in the oil following applies:
•
for Ammonia:
te ≥ t
oil
+ 5 K;
te ≥ t
oil
+ 10 K,when using a PAG oil (solubil-
ity of the refrigerant in the oil).
•
For R22, R134a, R404A, R407C, R410A,
R507, CO2, natural gas, carbohydrate molecules:
te ≥ t
oil
+ 10 K, wherein solubility of the
refrigerant in the oil.
•
To determine the permitted difference
between the discharge temperature (te)
and oil intake temperature (t
oil
) the set
viscosity and the solubility diagram for
the refrigerant-oil pair from the lubrication supplier need to be adhered to.
8.
Ensure that the oil viscosity will be ≥7...70 cSt (=
10-6 m²/s) for the oil supply to bearings. Take
into account the drop in viscosity due to refrigerant dissolved in the oil!
9.
Limits for temperature differences will be considered in compressor selection programs.
10.
The oil temperature at the compressor inlet must
be at least 18°C, the oil must be preheated if
necessary.
11.
The rate of temperature change at compressor
suction side should not exceed 0,1 K/s.
12.
Rotation direction: view of compressor’s driving
shaft clockwise.
13.
For individual cases outside the permitted speed
coordination needs to made with the manufacturer.
p
p
0
Δp
π
t
0h
t
e
t
c
t
oil
Maximum permitted pressure
Suction pressure
Pressure difference
Pressure ratio
Suction temperature (compressor inlet)
Discharge temperature (compressor outlet)
Condensing temperature
oil inlet temperature into the compressor
Notes:
1.
During tests of a certain application case, all the
conditions specified in the table must be considered and adhered to.
2.
Should the given limits not be adhered to in individual cases, then the manufacturer needs to be
contacted.
3.
In addition to the application limits stated in the
tables, the applicable operating conditions of the
compressor type in question must also be considered (e. g. start-up regime, oil pressure, oil
quantity etc.).
4.
Depending on the refrigeration requirements,
economiser operation takes place at a control
slide position between 100% and approx. 70%
control slide position.
5.
When using R134a as a refrigerant and a evap-
orating temperature > 60 °C consultation with
the manufacturer must be made.
7.12.5
Water quality requirements,
parameters
All water bearing components from the manufacturer
deliver an optimum performance and provide maximum protection from corrosion, provided you meet
all of the limiting values recommended in VDI 3803
issue 2010-02 (Tab. B3) for non-corrosive water and
adequate water conditioning.
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Hint!
If you fail to adhere to the limiting values stated in VDI 3803, the manufacturer cannot provide any warranty for
water carrying parts within its supplied
components.
Clarification as to whether or not it is
possible to adhere to these limiting
values with the respective water conditions should be agreed on with a specialist company during the planning
and design phase.
The limiting values as per VDI 3803, as required for
the use of carbon steel components in non corrosive
water systems, are listed below.
Water quality requirements, parameters
Criterion
Value Unit
Appearance
clear, with-
out sedi-
ment
Colour
colourless
Odour
none
pH level at 20 °C
7.5 - 9.0
Electrical conductivity
LF < 220 mS/m
Soil alkali
Ca2+,
Mg
2+
< 0.5 mol/m³
General hardness,
for stabilization
GH < 20 °d
Carbonate hardness without hardness stabilizer
KH < 4 °d
Chloride Cl < 150 g/m³
Sulphur
SO
4
< 325 g/m³
Water quality requirements, parameters
Criterion
Value Unit
Active biological
components
KBE < 10,000 per ml
Thickness factor EZ 2 - 4
The use of carbon steel and cast iron is required in
the most of applications water conditioning with corrosion inhibitors.
The use of stainless steel requires very special monitoring of water in apply to Chloride contents (risk of
stress crack and pitting corrosion).
Hint!
Recommend when using plate heat
exchangers in the refrigerant circuit
< 100 ppm Cl while using steel 1.4301
and
maximum 40°C wall temperature in the
plate heat exchanger
< 200 ppm Cl while using steel 1.4401
and
maximum 100 °C wall temperature in
the plate heat exchanger
fig.28: Corrosion resistance in presence of chlorides
X
Chloride ion concentration in ppm Cl
-
Y Wall temperature heat exchanger in °C
A AISI 304
B AISI 316
C SMO 254
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Description of Design and Function
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Hint!
Manufacturer's recommendation: Use
uncontaminated secondary refrigerants and cooling media, in particular in
chillers and when using of plate heat
exchangers.
The media quality must be assured by
means of an appropriate filter on the
inlet to the heat exchanger. The mesh
for such a filter must be
≤ 0.9 mm!
Should the chiller be required to
remain in operation during filter cleaning, double filters must be used. Pressure loss through the filter must be
taken into consideration on the building side when configuring the pump.
The manufacturer recommends enlisting the services
of a reputable water conditioning company.
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8 START-UP
8.1 Important information for start-up
Warning!
Contact with live components is prohibited.
Hint!
The Customer Service department of
GEA Refrigeration Germany GmbH
offer comprehensive support for starting up the screw compressor package.
For contact details, please refer to the
chapter entitled "Technical customer
service".
Warning!
The screw compressor package must
only be operated by suitably skilled
personnel who are familiar with the
contents of the operating manual for
screw compressor packages.
The safety regulations for refrigeration
plants must always be observed in
order to prevent damage to the screw
compressor package and injury to the
operating staff.
The screw compressor packages are tested and
accepted at the works. By the time these screw
compressor packages are delivered to the customer, the following work will have been carried
out:
•
Complete installation of the cooling system and
in particular:
–
cleaning and drying the refrigerant and oil
circuits
–
Leak test with air
–
Evacuation of the refrigerant circuit and filling
with protective gas (nitrogen) to a pressure
of 0.3 to 0.5 bar (above atmospheric)
•
Electrical wiring and testing of the wiring
•
Factory setting for the parameters on the control
•
Factory setting of the safety and monitoring devices
•
Works trial runs (at the request of the client)
The following points must be observed before
commencing with the start-up:
–
Check of the external condition of the screw
compressor package (check of insulation, transport damage... ).
–
The area around the machine in which the startup is carried out must be marked and secured
against the access of unauthorised persons. Sufficient lighting of the working area must be
ensured to prevent personal injury and material
damage.
–
Personal protection gear (work clothing, work
boots, gloves) must be worn during all work on
the screw compressor package. There is a danger of impact and stumblingfrom protruding parts
on the screw compressor package (e.g. valve
caps). There is also the danger of cut wounds on
sharp edges and rough surfaces. All activities
must therefore be carried out with particular
attention.
–
Suitable hearing protection must be worn in
order to protect against damage to hearing or
deafness.
–
Thermal hazards resulting in injuries due to
burns or freezing may occur on contact with
parts of the system which are at a very high or
very low temperature. Personal protective equipment must be worn.
–
Suitable tools or special tools must be used.
–
Check that all electrical work has been carried
out in accordance with the standards (e.g.protective earth, insulation, shielding, covers). If necessary, an earth connection must be provided.
–
Pipes and pipe sections must be secured to
ensure sufficient mechanical strength. The pipes
and equipment of the screw compressor package must not be entered.
–
Operating media (nitrogen, oil, refrigerant) can
escape. Preventive measures must be taken to
collect and dispose of them in an environmentally responsible manner (e.g.using an oil pan).
Personal breathing protection must be kept
ready in the event of a refrigerant leak. The
safety data sheets of the oil and refrigerant used
must be read prior to commencing start-up work.
Familiarise yourself with the evacuation plan of
the installation location.
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GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015 53
–
Danger!
Solid mounting of the coupling protection must be checked. Start-up must
not be carried out with the coupling
protection mounted.
–
Check the protective gas filling (a positive pressure ≥ 0.2 bar must be present)
Hint!
If defects are found, notify GEA Refrigeration Germany GmbH Service and
proceed according to their instructions.
8.2 Basics
The compressor must only be switched on if the
screw compressor package has been correctly connected and filled with operating materials.
The activities described in this "Start-up" chapter
must be carried out in the prescribed sequence.
The screw compressor package is operated via the
terminal of the control unit.
After the target values have been entered, both automatic and manual operation are possible.
The software of the control device and operation via
the terminal are described separately in the operating manual for the control system.
8.3 Connecting the screw compressor
package
Caution!
All mechanical connections must be
made according to the R+I diagram
which is valid for the project. The R+I
diagram is part of the product documentation.
Caution!
All electrical connections must be
made according to the circuit diagram
which is valid for the project. The circuit diagram is part of the product
documentation.
Check that components which have been removed
for transport, separately delivered components and
components provided by the customer are firmly
attached.
Check that all locating bolts are tight.
8.3.1
Connecting the pipes
The nitrogen filling of the screw compressor package
must be purged by opening the vent valves before
the connection of the pipes.
Establish all pipe connections so that the transmission of thermal expansion and vibration to the screw
compressor package is limited as far as possible.
Bellows-type expansion joints made of steel, or flexible metal hoses can be used for refrigerant and oil
lines, bellows-type expansion joints made from rubber can be used for water connections.
Provide all pipe connections directly at the unit with
fixed points.
•
Connection of:
–
Suction line
–
Pressure line
–
Oil cooler water connection
•
If units are equipped with a safety valve: Connect safety valve to the blow-off line.
•
Integrate relief valve in the suction line.
•
if units are equipped with a refrigerant cooled oil
cooler:
–
Connect the refrigerant feed line from h.p.
receiver (note geodetic height above oil
cooler).
–
Connect the evaporated refrigerant line to
the condenser
•
If refrigerant injection is used: Connect the refrigerant feed line from condenser or h.p. receiver
•
If an economiser is used: Connection the suction
line of the economiser to the charge connection.
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54 GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015
Hint!
In principle, all the connections must
be made in accordance with the P+I
diagram applying to the respective
project. Attach the pipes to the screw
compressor package in such a way
that no additional static or dynamic
loads are imposed.
All the pipes and systems to be connected must be checked for leaks
when the work is complete.
8.3.2 Electrical connection
Danger!
Contact with live components is prohibited.
The screw compressor package has been designed
for plug-in and reliable automatic operation.
All connections must be carried out according to the
current installation regulations.
Connections to the screw compressor package must
be flexible and free of loads.
Hint!
Dimensioning of the inlet pipe crosssections must be according to DIN
VDE 100 Part 520.
Before starting work, make sure that all parts to be
connected are de-energised, e.g. by removing the
main fuse in all phases or installing a jumper wire.
The insulation resistance of the electrical tools and
fixtures and wiring is to be checked. The connection
may only be undertaken if this value lies in the allowable range.
Connections and almost all external connections are
pre-wired at the factory.
Warning!
Produce the earth connection according to the designation in the general
assembly drawing. See chapter "Designation of the earth connection".
The electrical consumers and sensor must be connected according to the circuit diagram. All electrical
connections must be made according to the circuit
diagram, e.g.
–
Compressor drive motor
–
Compressor control supply
–
Oil heater
–
Oil pump
Some external components, such as the second
EMERGENCY STOP switch, the ammonia sensor
and the fans of the machine room, must be connected by the system erector on site.
Hint!
Check that terminal screws (in the
switching cabinet) are tight.
8.4 Paint and insulation
Damage to the paint and insulation during transport
and installation must be carefully repaired.
8.5 Start-up procedure
The following procedures should be completed in the
sequence in which they are described:
8.5.1 Checking the electrical connection
Danger!
Contact with live components is prohibited.
Check that all electrical work has been carried out in
accordance with the standards (e.g.protective earth,
insulation, shielding, covers). If necessary, an earth
connection must be provided.
8.5.2
Leak test
Hint!
See type plate for permissible operating pressure.
The necessary safety precautions should be taken
before performing the leak test.
An approx. 3-hour pressure drop test with dry nitrogen is used for the test. Test pressure: 7 bar
A pressure drop of 2% is allowed during the 3 hours.
Fluctuations in the ambient temperature must be
taken into account.
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Caution!
Checking devices which could be
damaged by the specified test pressure must be removed or blocked
before the leak test is performed.
A record should be kept of the pressure test, noting
the pressure in the pipes tested, the ambient temperature and the outside temperature in the shade at
hourly intervals.
The removed measuring and control instruments
should be reinstalled after completion of the leak test
and if there are no leaks in the package/chiller.
Test strategy
Dry nitrogen is used as the test medium. After reaching the test pressure, the pressure drop is measured
via the differential pressure measurement. This may
only change by 0.02 bar within an hour. If the display
device does not indicate a leakage through foam formation, the system is sealed.
Testing devices
A pressure gauge with an accuracy of 0.5% over the
entire measuring range, with a digital resolution of
0.01 bar must be used for the measurement.
The testing described here is based on pressure
gauges with pressure gauge and LEAK mode from
Keller.
Display devices
A foaming agent must be used as the means to indicate leakages. A solution of 50 parts water and 1
part detergent can be used as the foaming agent.
Leaks are detected through formation of foam. A
leak detection spray can be used in problem areas.
Carrying out the test
1.
Wet all connecting joints (welded seams, flange
connections, screw fastenings, etc.) with foaming
agent. Remedy any leaks detectable from the
noticeable formation of foam.
8.5.3
Drying, vacuum
After the leak tightness test has been completed, the
plant must be evacuated and undergo a vacuum test
for 3 hours. Evacuation is used to remove air and
moisture from the plant.
A vacuum pump must be used for evacuation.
The permissible increase in vacuum is maximum
6.66 mbar over a period of 3 hours.
fig.29: Vacuum required to remove moisture from refrigerating
plants
X Room or Wall temperature in °C
Y Vacuum in mbar
A Vacuum required to remove moisture from
refrigerating plants
Measured values have to be checked and recorded
hourly after reaching the required vacuum. After the
vacuum pressure, the temperatures in the machine
house and the outdoor temperature in shade must
be entered in the log. After the vacuum test, the
pressure compensation must be carried out with
NH3.
Warning!
Shut the oil pump during evacuation!
See also "Evacuation on refrigerant side" in the
chapter "Maintenance work".
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8.5.4 Operating position of valves
For the positions of the manually controllable fittings for the operation of the package/chiller, see the P+I diagram.
The layout and symbols used in the P+I diagram comply with the specifications of EN 1861, July 1998 Issue.
Caution!
The valves must be in operating position prior to the start-up of the package / chiller. Troublefree operation is only possible in this manner!
fig.30: Stop valve open
Stop valve open during normal operation
fig.31: Stop valve closed
Stop valve closed during normal operation
fig.32: Check valve
Check valve during normal operation
fig.33: Shuttable check valve
Shuttable check valve open during normal operation
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fig.34: Control valve
Control valve adjusted:
–
Start-up
–
when operating conditions change
fig.35: Shuttable check valve
with integrated control function
Shuttable check valve with integrated control function open during normal operation
fig.36: Solenoid valve
Controlled by the controller (e.g. GEA Omni)
fig.37: Change-over valve
Change-over valve (3-way valve), opened from below in arrow
direction
fig.38: Oil pressure control valve
Operating position: shut
Δp x,x ± x bar control pressure to be set vis-à-vis reference pres-
sure (see P+I diagram)
Caution!
An oil pressure being set too high or too low may result in serious compressor damage or
even the total breakdown of the compressor after just a short period of operation!
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fig.39: Overflow valve, safety valve
Overflow valve, safety valve
fig.40: Pressure controlled check valve
controlled self-sufficient
fig.41: Quick acting valve, spring-loaded
manually operated if necessary
fig.42: Charging valve, drain valve
–
½” connections
–
with cap
fig.43: Service valve
–
Connection Rp ¼”
–
For pressure gauge and pressure transmitter
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fig.44: Oil temperature limiter
controlled autonomously using control element
fig.45: Temperature controlled control valve
Autonomous control via sensor
8.5.5 Oil charge
Caution!
Check the oil grade to be charged! See
contract/project or recommendation of
GEA Refrigeration Germany GmbH. A
comprehensive overview of the allowable oil types is provided in "Technical
information on lubricating oils". This
technical information is part of the
product documentation.
For severely hygroscopic oils, the oil
container must be placed under a protective atmosphere.
The vacuum present in the screw compressor package before pressure compensation may be utilised
for charging the package with oil. A separate oil
charging pump is required after the pressure compensation and for refilling with oil.
The connection of the oil draining or oil charging stop
valve (090) must be connected with the oil charging
container.
Before charging with oil, switch the valves to the
operating position.
The stop valve (090) must be opened until the oil
level has reached a value between the upper edge of
the sight glass indicator MIN (N10b, data sheet
990565) and lower edge of the sight glass indicator
MAX (N10c, data sheet 990565).
The oil separator is generally charged with oil via the
oil cooler.
When charging with oil for the first time, oil must be
charged via the service valve (135) too. To this end,
the stop valve (065) must then be closed.
While operating the package, the oil level must be
regularly checked (see chapter "Oil level check").
Caution!
Due to the use of selected components, the refrigerating machine oils
tend to absorb more moisture. Therefore, when charging a compressor the
oil should be allowed to come into
contact with air for a short time only.
The contents of an opened drum have
to be used up within one working day,
provided the drum is properly closed
between charging.
8.5.5.1 Pressure compensation with
the cooling system
Re-establish the vacuum. Carry out pressure compensation via the service stop valve (285).
8.5.5.2
Checking the direction of rotation of the oil pump motor
The oil pump is started with the driving motor electrically blocked (service). The stop valves are in the
operating position.
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The direction of the arrow given for the oil pump
must correspond to the direction of rotation of the oil
pump motor.
Caution!
Since the slide ring shaft seal of the oil
pump is dependent on the direction of
rotation and can be damaged when
this direction is wrong, checking must
be reduced to a very short running
period (less than 2 seconds).
The adjusted differential pressure between the oil
pump pressure side and the unit final pressure is
checked with the oil pump rotating in the correct
direction. It must not fall below the prescribed set
value in the P+I diagram.
While the compressor is not running and the oil has
not yet reached the operating temperature, the differential pressure can be slightly higher than the indicated value.
The differential pressure can be changed by rotating
the spindle on the oil pressure control valve. (The differential pressure is increased by turning it inwards
and vice versa).
8.5.6
Checking the fault monitoring
1.
Disconnect the incoming feeder of the compressor drive motor from the mains supply when
checking the safety device (e.g. remove LV/HBC
fuse links).
2.
Apply voltage to the control device.
3.
Check the built-in pressure transducer and
resistance thermometer for correct wiring.
To do so, loosen the relevant contacts. The message "Broken wire <sensor XXX>" appears on
the display of the control. Check that the display
is correct after the contact has been re-established.
Further information can be found in the controller manual.
4.
Check limit values.
Limit value = see parameter list
5.
Switch on the screw compressor package/chiller
from the controller.
6.
"Oil circuit monitoring failure” must be indicated
after a starting delay time of 20 sec.
7.
Reconnect the oil pump motor to the mains supply.
8.
Check the excitation of the solenoid valves of the
adjusting device for capacity control in the Mini-
mum direction.
9.
Simulate the minimum end position of the control
slide and check the switching function of main
switch and star-delta contactor (for motors with
star-delta starting).
10.
Checking the switching function of the solenoid
valve by forcing the digital outputs.
11.
Check the "Oil circuit monitoringfailure". only for
external oil pumpAfter 6s, the of the compressor drive motor must be shut off. To do so, the
valve (70) must be throttled in such a manner
that the alarm value for oil difference pressure as
stated on the parameter list is ot reached.
12.
Set the motor current limitation acc. to nominal
motor data. See parameter list!
8.5.7 Checking of the safety pressure
limiter
1.
Setting of the shut-off values as per the panel
data report
2.
Switch on the compressor package
3.
Initiation of the shut-off value
4.
Check the reaction:
–
Compressor must shut off immediately
–
Fault report on the display of the control unit
8.5.8 Checking of the emergency-OFF
button.
Hint!
Upon actuation, the emergency-Off
button must immediately shut off the
compressor.
1.
Actuation of the emergency-OFF button.
2.
Check the reaction:
–
Compressor must shut off immediately
–
Fault report in the display of the control
3.
Resetting of the emergency-OFF actuation to
end the test.
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8.5.9 Adjustment of oil pressure
Danger!
The oil pressure being set too high or
too low may result in serious compressor damage or even total breakdown
of the compressor after even a short
period of operation!
Before the compressor drive motor and therefore the
unit can be started, the oil pressure must be set correctly by adjusting the oil pressure regulating valve
(075).
For adjustment solely the oil pump must be started.
For units with the control GEA Omni, digital output
must be forced for this.
The set value of the oil differential pressure should
be taken from the P+I flow chart of the specific
project.
Oil differential pressure = oil pressure item (110)
- discharge pressure item (105)
The differential pressure can be changed by rotating
the spindle on the oil pressure regulating valve (the
differential pressure is increased by turning it
inwards and vice versa). To do so, the seal on the oil
pressure control valve (075) must be removed.
In comparison to normal operation conditions, the oil
differential pressure can be slightly higher if only the
oil pump is operated or if the operating temperature
is not reached yet (with the valve open to the same
degree).
In this case, the oil differential pressure should be
readjusted (according to the value in the P+I flow
chart) after start of the unit and reaching of the operation temperature.
8.5.10
Checking the direction of rotation
of the drive motor
Warning!
The coupling must not yet connect the
motor and compressor!
–
Secure the electric switchgear so as to prevent
the compressor drive motor from being switched
on accidentally.
–
With the control slide in the MIN or MAX position,
it should be possible to rotate the compressor
shaft easily and smoothly by hand. When checking the direction of rotation of the compressor
driving motor pay attention to the conditions for
switching the compressor on.
fig.46: Motor direction of rotation
A Compressor
B Motor
–
The compressor drive motor is started directly
and then switched off again by forcing the digital
outputs.
Hint!
Prior to the start-up of the compressor
drive motor, the manufacturer's information, e.g. on the lubrication of the
motor, must be followed at all costs.
–
If the direction of rotation of the motor is incorrect, it should be corrected while the electric
switchgear is secured to prevent the motor from
being switched on accidentally. Then the motor
must work for at least 1 hour, unencumbered
and free from errors. This is important in order to
dry out residual moisture in the motor (caused
during transport or storage).
–
The coupling protection must be in place during
this start-up period as required by the labour
safety regulations.
–
After checking the direction of rotation of the
drive motor, the coupling may be connected with
the motor.
8.5.11 Mounting the coupling
1.
The electric switchgear is secured to prevent it
from being switched on accidentally.
2.
Mount the coupling while observing the instructions of the separate documentation.
3.
The values for radial and angular deviations
given in the coupling documentation must be
checked and corrected if necessary. The axis
distance between the compressor drive motor
and the compressor must be checked.
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4.
The real values have to record at data sheet of
coupling documentation. Please send back a
copy of the filled data sheet to:
GEA Refrigeration Germany GmbH
Holzhauser Straße 165
13509 Berlin
Fax: +49 (0)30 - 43 592 759
Caution!
Observe the maintenance instruction!
Regrease the coupling at the prescri-
bed intervals if scheduled in the maintenance instruction for the coupling!
8.5.12 Checking the water circuits
Check whether the cooling and cold water pumps
are running and the shut-off fittings in the cooling
water circuit are in their operating positions.
While the unit/ chiller is operating under project conditions, adjust the cooling water control so that the
condensing and oil temperature lies within the permissible range.
8.5.13 Initial start-up
After carrying out the aforementioned works, the
SCP can be commissioned in accordance with the
operating manual of the control device.
1.
Switch on the control voltage of the control
device.
2.
Remedy and acknowledge existing fault messages.
3.
Select manual operating mode.
4.
Turn on SCP.
8.5.14 Checking the adjustment of the
control slide
1.
SCP is running.
2.
Select manual operating mode.
3.
The maximum end position (100%) must be
reached and signalled when the "Increase
power" button is pressed.
4.
The minimum end position (0%) must be
reached and signalled when the "Decrease
power" button is pressed.
5.
Vent the adjusting device by moving the control
slide backwards and forwards about ten times.
8.5.15
Checking the control slide adjustment times
Caution!
Only adjustment times between 30 and
60 seconds are permissible.
The throttle valves of the solenoid valves are adjusted in the factory in such a manner that they ensure
an optimal adjustment time of the control slide of
between 30 and 60 seconds.
While running at operating temperature and pressure
conditions, determine the adjustment times needed
when the control slide is continually moved from the
maximum end position to the minimum end position
and back. For the automatic system to run smoothly,
the adjustment times in either direction must be
approximately the same.
The adjustment time can be adjusted with the help of
throttle valves DS5 and DS6.
Hint!
See the assembly instructions for the
screw compressor.
8.5.16 Checking the oil cooler
Guide value for oil temperature = see parameter
list
Oil cooling with water-cooled oil cooler
The water volume must be regulated so that the
cooling water volume corresponds to the project
value. The inlet and outlet temperatures must be
checked. The oil temperature adjusts automatically
via the 3-way valve.
Checking the oil cooling with refrigerant-cooled
oil cooler
No regulating or checking required.
8.5.17 Adjusting the amount of injection
oil and the oil temperature
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8.5.17.1 Screw compressor packages
without refrigerant injection
The amount of injection oil and the oil temperature
directly influence the discharge temperature of the
compressor. The amount of injection oil is adjusted
under operating conditions through the injection oil
control valve.
Standard values for discharge temperature
t t
max
NH3/HP t ≥ t
oil
+ 20K 30K 95°C
NH3/LP t ≥ t
oil
approx. 45 ... 60°C 80°C
Freon/HD t ≥ t
oil
+ 15K 80°C
R22/LP t ≥ 45 ... 60°C 80°C
8.5.17.2 Compressor units with refrigerant injection
The oil temperature is changed by setting the injection oil control valve. The more the shut-off valve is
throttled, the more the oil temperature decreases. If
the oil temperature becomes too low or reaches the
lower range, the setpoint for the discharge temperature should be set higher accordingly. In the first setting of the oil circuit, the control valve for injection oil
is opened approximately half a turn.
The discharge temperature is then regulated to the
value indicated in the parameter list by means of the
thermostatic expansion valve.
Guide value for compressor end temperature: t
e
= 60 + 10°C (for NH3)
Other refrigerants on request.
8.6
Start-up after long standstill periods
1.
Inserting the main fuse
2.
Switching on the control unit according to the
operating manual.
3.
Checking all parameters on the control unit display. See parameter list.
4.
Checking the settings of all control and safety
devices.
8.7 Restarting after approx. 1 year
standstill
•
Change the oil filter inserts (see maintenance
instruction).
•
Switch on the oil heater at least one hour before
starting the screw compressor package/chiller.
•
Open the stop valve on the suction side and the
pressure side (or check valves which can be
shut off).
•
If fitted: Open the stop valves (or shuttable check
valves) in the suction line of the economiser.
•
If fitted: Open the refrigerant supply to the thermosyphon - oil cooler.
•
If fitted: Open the manual stop valve of the refrigerant injection.
•
Remove all non-condensable gases by venting.
To this end, check the condensing pressure and
temperature (see parameter list).
•
Check the oil collection sump and drain if necessary.
•
Switch on the compressor and observe the operating instructions of the electrical switchgear.
Make a screw compressor package/chiller test
run in order to test the sensor and actor technologies (for operation and indicating precision).
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9 USE, OPERATION, CONTROL
9.1 Use in explosive atmospheres,
installation zones 1 and 2
Danger!
The same regulations apply to the
operating instructions for screw compressor packages in potentially explosive atmospheres as described in the
respective applicable operating manual.
In addition to this, the following extensions apply:
1.
In addition, the legal safety regulations apply for the people responsible for operating the screw compressor package, and must be conformed with respect to the transport, assembly, operation and
maintenance and if necessary the
replacement of sub-assemblies,
etc. in potentially explosive atmospheres.
The operator directives must be
complied with in this context – see
also section: Safety instructions
for compressor, Appendix E and
Screw compressor package,
Appendix E. Both documents are
an integral part of the documentation.
2.
The relevant electrical engineering
regulations for installations in
potentially explosive atmospheres,
especially EN 60079-10, apply to
the installation and connection of
electrical components. Appropriate, prescribed cabling material
must be used.
3.
The entire screw compressor package must be earthed by the operator.
9.2 Important information for the operator
The screw compressor package must be only be
operated by trained and qualified personnel who are
familiar with the contents of the operating manual for
GEA Refrigeration Germany GmbH screw compressor packages.
The safety regulations for refrigeration plants must
always be observed in order to prevent damage to
the screw compressor package and injury to the
operating staff.
Hint!
The screw compressor package is
operated via the control panel of the
control unit. If the control is included
in the scope of delivery, the operating
staff must be familiar with the contents
of the complete documentation of the
control unit. The documentation for
the control unit is an integral part of
the product documentation.
9.3 Prerequisite for switching on
The screw compressor package has been designed
for automatic operation; the control unit controls the
switching on and off of the compressor and its
capacity adjustment.
Continuous operation and observation of the screw
compressor package is not necessary in automatic
mode. The necessary steps for switching on the
screw compressor package can be found in the controller documentation.
If the screw compressor package is controlled manually, it must be operated from the refrigerator room.
In particular, the repair and maintenance instructions
must be complied with.
The following prerequisites must be fulfilled for
switching on the screw compressor package:
1.
The main power must be available and switched
on.
2.
The screw compressor package must be sufficiently filled with refrigerant and oil.
3.
The valves must be in the operating position.
4.
The oil level in the oil separator must be within
the permissible range.
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5.
The cooling and cold water pumps must be in
operation.
6.
The supply of cooling water or coolant to the oil
cooler must be ensured.
7.
The oil heater in the oil separator must have
heated the oil sufficiently.
Hint!
The oil heater in the oil separator can
be switched on while the screw compressor package is not running. It is
then automatically switched off when
the screw compressor package is started and switched on when it is shut
down. If the ambient temperature is
below 5°C, the oil heater must be
switched on at least one hour before
the screw compressor package is started.
8.
The rated current limitation has been set according to the motor rating.
®
The screw compressor package can be switched
on as per the controller operating manual.
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9.3.1 Overview of the operating modes
Modes Signal for …
Name Remark Start/Stop Capacity +/-
0 Service Oil pump by itself
Compressor motor blocked
1 Manual
+ Manual
Manual control via Touch Panel (TP) Manual Manual
2 Manual + Auto Manual Start/Stop via TP and full automatic local
capacity control
Manual Auto
3 Auto + Auto Full automatic start/stop and local capacity control Auto Auto
4 Remote
+ HW (cont)
Start/stop and capacity demand via digital contacts
(hardware) from a remote master controller. The GSC
TP derives from the continuous +/- signals the pulses
for capacity (indirect).
External External
continuous
5 Remote
+ HW (pulse)
Start/stop and capacity demand via digital contacts
(hardware) from a remote master controller. The master also generates the +/- signals as pulses for controlling the slide capacity directly.
External External
pulses
6 Remote
+ HW (loc.
SW)
Start/Stop from a remote master controller via digital
contacts (hardware). The GSC TP controls the output
depending on a local setpoint (TP) and from this setpoint also automatically switches the product ON/OFF.
External
+ setpoint
deviation
Local
Setpoint
7 Remote
+ HW (ext.
SW)
Start/Stop from a remote master controller via digital
contacts (hardware). The GSC TP controls the output
depending on an external setpoint (analog input) and
from this setpoint also automatically switches the
product ON/OFF.
External
+ setpoint
deviation
Remote
Setpoint
8 Remote
+ Net (cont)
Start/stop and capacity demand via network from a
remote master controller. The GSC TP derives from
the continuous +/- signals the pulses for controlling the
capacity (indirect).
Network Network
continuous
9 Remote
+ Net (pulse)
Start/stop and capacity demand via network from a
remote master controller. The master also generates
the +/- signals as pulses for controlling the capacity
directly.
Network Network
pulses
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Modes Signal for …
10 Remote
+ Bus (loc.
SW)
Start/stop from a central master controller via a bus
signal. The GSC TP controls the output depending on
a local setpoint (TP) and from this setpoint also automatically switches the product ON/OFF.
Network
+ setpoint
deviation
Local
Setpoint
11 Remote
+ Bus (net.
SW)
Start/stop from a central master controller via a bus
signal. The GSC TP controls the output depending on
an external setpoint sent externally via the network
and from this setpoint also automatically switches the
product ON/OFF.
Network
+ setpoint
deviation
Network
Setpoint
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9.3.2 Setting of setpoint and limiting
values as well as safety devices
Caution!
The correct setting of all setpoint and
limiting values is a prerequisite for the
safe operation of the SCP.
For the setting of the setpoint and limiting values, the
1.
details (steps) in the control operating manual
and
2.
the project-related data are
instrumental. The program-based setpoint and limiting values as well as the setting values of the safety
device are stated in the project-based parameter
list. The parameter list forms part of the documentation for the controller.
9.4
Operation of the screw compressor
package
Caution!
Read the control documentation carefully.
Contact the GEA Refrigeration Germany GmbH technical customer service if you require assistance.
The screw compressor package is operated using
the control (standard: GEA Omni).
The GEA Omni is mounted directly on the screw
compressor package as standard, but can also be
arranged in a control centre.
The GEA Omni consists of the control unit with operator keypad and display unit (TouchPanel), indicator
lights for "Running", "Warning" and "Alarm", the
emergency stop button, the output relays and the
casing.
All switching, operating and control actions are carried out via this TouchPanel. The TouchPanel is the
interface between the man and the machine.
GEA Omni performs the following functions as
standard:
–
Display of all important physical and technical
parameters, e.g. pressure, temperature, motor
current, capacity, number of operating hours,
operating mode and status signals
–
automatic start up and shut down of the compressor package and capacity control dependent
on the relevant parameter for the application
(e.g. the suction pressure or an external temperature),
–
Monitoring of all operating parameters,
–
Compressor capacity limitation if the measured
discharge pressure, suction pressure, secondary
refrigerant temperature or motor current indicate
an overload,
–
Fault memory with date and time,
–
Wire failure detection for all analogue input signals
–
Password protection for preventing unauthorised
access to important parameters
–
Non-volatile saving of programme,
–
MPI communication with a master controller
(optionally via Profibus-DP, Modbus RTU or
Modbus TCP).
9.5
Instructions regarding failures, their
causes and remedies
The screw compressor packages/ chillers manufactured by GEA Refrigeration Germany GmbH are
highly advanced, automatic and extremely efficient
systems. Nevertheless, faults can occur and may
complicate any continuous operation of the plant or
cause a failure of a part or the entire plant.
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Table of malfunctions
Fault Cause Remedy
The suction pressure is too low,
performance is reduced and the
system overheats.
Slow loss of refrigerant through
leaks in the refrigerant circuit.
Check the entire system for leaks.
Eliminate leakage, replenish refrigerant if necessary.
Pressure sensor defective. Replace pressure sensor.
Defective capacity control devices
in the compressors
Check capacity control devices,
especially connections of solenoid
valves
Suction filters are clogged Clean or replace the filter insert.
The suction pressure increases, the
compressor(s) frost up to impermissibly high level or make noises that
suggests fluid (refrigerant) in the
compressor.
The compressor/s are sucking in
wet steam or liquid when started
up. The safety device to prevent a
too-high liquid level is not responding.
Check the filling of the system,
drain any refrigerant, repair safety
device. Check for superheating.
The condensation pressure is too
high.
There is air or other non-condensable gases in the refrigerant circuit.
Vent the refrigerant circuit.
The compressor(s) will not start-up
after switching on or it shuts down
immediately after starting again.
The electrical circuit is interrupted
by a unit in the safety chain.
Turn on the power, check safety
devices and replace or correctly
adjust if necessary.
No oil pressure is building up in the
package/chiller. The oil circuit is
disturbed by clogged oil filters or
leaks.
Exchange or clean oil filter elements, eliminate leaks and replenish oil.
The compressors do not adapt to
the required capacity.
The capacity control device is malfunctioning due to disturbances in
the oil circuit or mechanical influences.
Check the oil circuit. The compressors should only be repaired by
experts. Check the position detector of the compressor control slide.
The compressors are shut off very
often by the maximum pressure
governor.
The condensation pressure is too
high.
See above.
The maximum pressure governor is
defective or set wrongly.
Remove the maximum pressure
governor, repair it, set it correctly or
replace it.
The compressors are shut off very
often by the minimum pressure
governor.
The suction pressure is too low.
Open all valves on the suction side
of the compressors.
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Table of malfunctions
Fault Cause Remedy
The pressure governor is defective
or set wrongly.
Remove the minimum pressure
governor, repair it, set it correctly or
replace it.
The heat transfer capacity of the
evaporator decreases.
Check the evaporator for elevated
oil concentration, drain oil if necessary.
When operting, the package/chiller
is louder than permitted.
The compressor(s) or the drive
motor(s) is/are defective.
Inform the GEA Refrigeration Germany GmbH customer service
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10 CLEANING, MAINTENANCE, REPAIR
Hint!
The obligation for signage to prevent
the unintentional switch-on of the
plant during cleaning, maintenance
and repair must be observed.
10.1 Use in explosive atmospheres,
installation zones 1 and 2
Danger!
The same regulations apply to the
maintenance instructions for SCPs in
potentially explosive atmospheres as
described in the respective applicable
operating manual.
In addition to this, the following extensions
apply:
1.
In addition, for the persons responsible for maintaining the SCP, the legal safety regulations concerning the installation of the SCP in potentially
explosive atmospheres with respect to the maintenance of the individual components or subassemblies or their complete replacement apply.
2.
The maintenance may only be carried out in
agreement / with the knowledge and release of
the operator.
3.
The maintenance and replacement regulations
resulting from the operating manual for the components are to be complied with.
4.
Appropriate special tools approved for the potentially explosive atmosphere must be used.
5.
Only original spare parts may be used. Otherwise, any claim of warranty is void or, in case of
damage, the operator is liable for this.
6.
Each maintenance inspection (see maintenance
book) must also include the checking of the
secure fit of the threaded connections for the
coupling safety hood.
10.2
Important information for service
personnel
The following chapter is primarily aimed at the maintenance and service personnel of the screw compressor package.
Hint!
Heed all safety instructions in this
manual.
Familiarise yourself with the local conditions of the screw compressor package installation site.
Adhere to all legal and local regulations of health, work and fire protection as well as the regulations which
must be heeded concerning the gases
to be compressed.
Please read this manual carefully and
completely prior to working on the
screw compressor package.
Familiarise yourself with the special
features of the screw compressor
package.
Caution!
There is an increased danger of slipping due to contact of operating media
with the floor!
The screw compressor package must be serviced by
appropriately trained operating staff only. For all
maintenance work, the maintenance instructions
must be complied with.
A maintenance checklist is part of the product documentation. The maintenance certificates in the maintenance checklist are completed and signed as part
of the inspection and maintenance by authorised fitters as evidence of the work done.
During the guarantee period, these confirmed maintenance certificates are a prerequisite for any claims
under the guarantee.
The responsible certified specialist company must be
informed if any repairs are required.
All maintenance and service tasks have to be carried
out with care to preserve the functionality of the
screw compressor package. Guarantee claims will
not be valid if the customer failed to follow the maintenance instructions.
10.3
Cleaning the heat exchanger
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10.3.1 Mechanical cleaning
Mechanical cleaning is a maintenance measure in
order to ensure the continuous safe operation of the
screw compressor package.
Components of the screw compressor packages
(e.g.suction filter) can be removed for manual
mechanical cleaning. Proceed in accordance with
the details in the applicable component documentation. After completing cleaning work, properly mount
the component and check for leakage.
10.3.2 Chemical cleaning
Chemical cleaning of the screw compressor package
is not recommended by GEA Refrigeration Germany
GmbH.
10.4 Maintenance
10.4.1 General instructions
Danger!
Contact with live components is prohibited.
Maintenance work on the running
screw compressor package is not permitted.
Work involving intervention in the refrigerant circuit
must only be carried out by qualified engineers in
accordance with the guarantee conditions.
The screw compressor package must always be
switched off before being dismantled. Before beginning the work, it must be ensured that all parts subject to maintenance/servicing are de-energised(e.g.
by removing the main fuse or installing a shorting
bridge).
The refrigerant must be removed from the applicable
parts of the system parts. This work must be carried
out with great care, taking into account the safety
regulations, so that the maintenance personnel are
not injured by the refrigerant or by the refrigeration
unit oil present in the system.
Parts of the system under pressure must be completely vented before opening. While carrying out the
repair, it is must always be ensured that a complete
pressure balance of the affected pressure chambers
with the environment is preserved.
During cleaning, repair or maintenance work, the
screw compressor package or its components must
be protected against the penetration of moisture in
order to prevent impairment of the function of the
components.
The chief principle must be to keep air and moisture
entering the screw compressor package to an absolute minimum. All foreign substances must kept as
far away as possible or eliminatedincluding
–
welding residues,
–
sealing remnants,
–
auxiliary materials such as grease, oil or solvents.
Welding and soldering work may only be performed
with written permission. The requisite protective
measures must be defined. These include:
–
personal protective measures when opening the
respective part of the system,
–
complete draining of the respective part of equipment,
–
cleaning with the appropriate cleaning agents,
–
concentration measurements,
–
ensuring sufficient ventilation and venting,
–
performance of all welding work with the use of
forming gas.
If gas filled pipes are opened for maintenance work,
these pipes must be in a gas-free condition.
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10.4.2 Repair work
Modifications and repair work may only be carried
out by qualified persons or persons with suitable
training with the manufacturer's consent and must
strictly comply with the rules set out in the maintenance instruction for the components concerned.
Hint!
The following maintenance notes must
be observed:
Only spare parts made by the original component
manufacturer may be used for repairs and for replacing wearing parts. These are available from the
spare parts department.
10.4.2.1
Repair information
Important features of the technology and production
process must be taken into account when repairing
the plant:
–
complete sealing of all devices and pipes.
–
Dryness and cleanliness of the entire plant.
–
Use of welding methods causing only a minimum
amount of dirt to collect in the plant.
–
Pipes bent on a pipe-bending machine only
using refrigerating oil.
–
If repairing the piping system from your own
stocks, we recommend that you use a pipe with
NBK surface quality (annealed and descaled,
mechanically or chemically descaled after
annealing).
–
When carrying out repairs to piping systems,
care should be taken to maintain the original piping routes.
–
Only pipes of sufficient material quality, which
are certified according to DIN 10216-2 should be
used.
10.4.2.2 Repairs of pressure vessels
subject to approval inspection
Hint!
The responsible monitoring body
(e.g.TÜV) must be notified in advance.
New inspection and approval is required after pressure vessels that are subject to approval have been
repaired or changed. Welding may only be carried
out by approved welders with a valid welder’s card.
10.4.3
Maintenance intervals
Caution!
The maintenance intervals in accordance with the maintenance schedule
must be observed.
The maintenance schedule is an integral part of the
product documentation. The maintenance schedule
contains all the maintenance instructions and certifications for the first 15 years of performance of the
screw compressor package. The maintenance certificates are completed and signed as well as acknowledged on the display of the control as part of the
inspection and maintenance by authorised fitters as
evidence of the work done.
During the warranty period, these validated maintenance certificates also serve as a precondition for
any warranty claim put to GEA Refrigeration Germany GmbH.
10.4.4
Maintenance work
Hint!
The documentation for the main components is a part of the product documentation. This contains important
information to be considered before
beginning the maintenance work.
10.4.4.1 Maintenance of the screw
compressor
Maintenance works are to be periodically carried out
on the screw compressor (see maintenance schedule). These include:
–
Measure axial play of bearings,
–
Check shaft seal,
–
Check primary slide movement,
–
Check the adjustment of the position sensor.
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Hint!
The maintenance works on the screw
compressor are described in the
installation manual of the compressor.
After 50,000 operating hours or in the 15th operating
year, a general check of the screw compressor is
planned by the manufacturer. Contact Customer
Service in this regard.
10.4.4.2
Changing the block mounting
filter element
Hint!
When must the filter element be
replaced or cleaned?
The oil filter element must be replaced
as specified in the maintenance checklist for the total product from GEA
Refrigeration Germany GmbH.
Loss in pressure during operation is
monitored by the internal control –
including a preliminary alarm function
for preventative replacement.
The following applies as a guide value
for replacement: The filter element
should be replaced after every 5000
operating hours or once each year.
Changing the filter element
1.
Shut down the screw compressor package/chiller
and depressurise the blocked mounting filter on
the pressure side.
2.
Remove the filter cover by loosening the four
cover screws.
3.
Remove the filter element by slightly turning the
mounting pin in the filter head.
4.
Check the O-ring and support ring in the filter
bowl for damage and correct positioning.
Replace parts if required.
5.
Replace glass fibre element, clean or replace
wire mesh.
The efficiency of the cleaning depends on the
type of dirt and the level of differential pressure
before replacing the filter element. If, after
replacing the filter element, the differential pressure is more than 50% of the value before
replacing the filter element, wire mesh must also
be replaced.
6.
Check that the type designation/manufacturer ID
number on the replacement element matches
the type designation/ID number on the filter’s rating plate.
7.
Place the replaced or cleaned filter element back
on the mounting pin by turning it slightly.
8.
Reposition the filter cover and tighten the four
cover screws. Ensure that installation occurs
without mechanical tension.
9.
Vent the housing of the block mounting filter.
10.4.4.3
Replacing the oil filter
1.
Switch the unit/ chiller off.
2.
If the oil filter is very dirty, it may be necessary to
replace it outside the normal maintenance
schedule.
3.
To change the oil filter insert, close the following
valves in accordance with the P+I diagram and
the oil filter documentation:
–
Stop valve in front of oil filter (item 65)
–
further stop valves in front of oil filter (if available), e.g. (item 220) if a thermostatic 3-way
valve (item 215) will be used
see P&I diagram
–
Stop valve function oil (item 70) for Grasso
SP1 or (item 190) for Grasso SPduo
–
Control valve - injection oil with integrated
check valve function (item 80)
Do not forget to note the number of valve
rotations when you close the valve (item
080). When opening the valve it must be
returned to its initial position (see point 10).
This is necessary to ensure the final temperature remains unchanged and therefore to
avoid possible vibrations in the oil line.
–
Stop valve bypass oil cooler (optional)
4.
Establish pressure compensation with the
atmospheric pressure.
5.
Drain oil.
6.
Remove the cover of the oil filter.
7.
Remove the oil filter element and properly dispose of it if it is highly soiled.
8.
Carefully insert a new oil filter element.
9.
Close the cover of the oil filter.
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10.
Reopen valves in accordance with item 3. The
valve (80) must be returned to its initial position.
11.
After the pressure has been compensated, vent
the oil filter via the vent valve.
10.4.4.4 Maintenance of the suction filter
10.4.4.4.1
Changing the filter element
The maintenance interval for changing or cleaning
the filter element is specified by the manufacturer of
the refrigeration system.
The contamination level and mechanical condition of
the filter element must be inspected at least once a
year.
Before opening the filter, always make sure the filter
housing is not under pressure.
Caution!
Refrigerant may leak out on opening
the filter. The safety data sheets for
the refrigerants in question must be
consulted and any prescribed protective measures observed.
To remove the element, proceed as follows:
1.
Unscrew the cover.
2.
Pull out the cover with the filter element.
3.
Remove the spring wire clamp.
4.
Twist the element away from the cover to
release the bayonet catch.
5.
Detach the element from the cover.
6.
Allow the element to drain off into a suitable container.
Caution!
When carrying out maintenance,
always inspect the sealing ring (Oring) of the cover for mechanical damage and replace it if necessary.
7.
Reassemble all parts with the new or cleaned filter element following the same procedure in
reverse order.
10.4.4.4.2 Cleaning the filter element
The metal-gauze element used in the filter can be
cleaned and reused several times before it has to be
changed.
Manual cleaning
Immerse the soiled metal-gauze element in a clean,
grease-dissolving liquid, then blow it through with
compressed air from the outside inwards. Here it is
important to place a cylindrical part – possibly wrapped in corrugated cardboard – inside the element to
catch the dirt particles.
Caution!
Never use wire brushes for cleaning.
Hint!
To avoid fatigue failures of the metal
gauze, strainer elements should be
replaced with new, original filter elements after being cleaned 4 – 5 times.
10.4.4.5 Oil draining, oil filling, oil
change
10.4.4.5.1 Importance of oil change
Aged oil demonstrates an increasing loss of ability to
lubricate. Because of this, all rotating components of
the compressor are endangered. The filter elements
become prematurely clogged and must be cleaned
and replaced at shorter intervals.
The oil in the screw compressor package/chiller must
be changed:
–
when the operating time of the oil charge has
reached the technically specified oil change
interval,
Warning!
Oil change intervals
Oil change with ammonia as the refrig-
erant after every 5,000operating hours
or after 1 year at the latest
.
Oil change with freon as the refrigerant after 10,000operating hours or
after 2 years at the latest.
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–
if the oil becomes unacceptably contaminateddue to a major accident (e.g. water penetration
into the refrigerant circuit).
The degree to which oil in refrigeration plants has
aged must be checked by analysis and in comparison of the data with those of fresh oil. Oil ageing can
also be judged from the darkening of the oil colour
and the deposits found in the oil filters. If the degree
of ageing cannot be assessed reliably by laboratory
analysis and the results of visual examination, it is
advisable to change the oil at the following intervals
(see maintenance checklist).
The assessment of the condition of the refrigerating
machine oil by means of a general visual inspection
(contamination) or laboratory analysis must be carried out:
–
after 5000 operating hours:
or
–
at the end of one year's operation
or
–
after remedying major damage.
or
–
if the oil is dark coloured or very cloudy.
10.4.4.5.2
Oil change, maintenance
work
Take oil samples for analysis and comparison with
the fresh oil data at regular intervals. Check the colouration of the oil visually and assess the degree of
contamination.
Depending on the results, the user must decide
whether to approve the postponement of filling the oil
until the next assessment date or whether to have
the oil changed.
Inadmissibly damp oil must be removed from the
compressor unit/chiller immediately.
10.4.4.5.3 Changing the oil
1.
The screw compressor package/chiller must be
run for at least half an hour to reach its operating
temperature before the oil can be changed.
2.
First shut down the screw compressor package/
chiller as described in the operating instructions.
3.
Open the stop valve in the bypass line around
the check valve on the suction side and the stop
valve on the suction side to equalise the pres-
sure between the screw compressor package/
chiller and suction line. If screw compressor
packages operated in parallel or other separate
chillers are present, the refrigerant should preferably be drawn off at a pressure which is
approx. 1 to3 bar above atmospheric pressure.
Then re-close the stop valves bypass and the
suction-side stop valve. Otherwise the pressure
can be reduced by opening the vent valve on the
suction filter and then disposing of the refrigerant
as specified by law.
4.
Then drain the used oil through the oil
draining/oil charging valves and dispose of it
(Caution! hazardous waste!). Once this has
been done, re-close the valve and if possible
continue to draw off the refrigerant with a compressor connected in parallel or a disposal
device until atmospheric pressure is almost
reached.
5.
Otherwise depressurise the screw compressor
package/chiller by opening the vent valve on the
suction filter, taking into account the safety rules
for refrigeration systems.
6.
Open the drain plugs and valves on the oil
cooler, oil separator and OMC block to drain any
residual oil. Then re-close the drain plugs and
valves.
7.
Replace the filter element of the oil filter; replace
and/or clean the filter element of the suction filter
combination.
8.
Evacuate the screw compressor package/chiller
using a vacuum pump.
Warning!
Shut off the oil pump!
9.
Pressurise the screw compressor package/chiller
with a slight overpressure via the stop valve
bypass check valve on the pressure side.
10.
Then check all components for leakages. On
successful completion, perform a complete pressure compensation with the discharge line followed by a repeated leakage test of the screw
compressor package/chiller. The oil charge oil
and start-up of the screw compressor package/
chiller must be accomplished in accordance with
the operating instructions.
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10.4.4.5.4 Used oil
Refrigeration machine oil drained from the circuit is
no longer suitable for use in refrigeration plants. It
has to be stored or transported in appropriately labelled containers in accordance with the legal provisions. The operator is responsible for its proper disposal.
10.4.4.5.5 Draining the oil
It may be necessary to drain the oil:
–
to inspect or repair the compressor
and
–
if there is too much oil in the circuit.
The oil must be drained in accordance with points 1
to 6 of the chapter entitled "Carrying out oil change".
The oil must be drained through the filling hose and
into a container suitable for waste oil.
10.4.4.5.6 Check the oil level
fig.47: Arrangement of MIN / MAX sight glasses
1 Sight glass - MAX (operation)
2 Sight glass - MIN (standstill)
The oil level is checked visually via the sight glasses
of the oil separator. The oil level should have a value
between 1/2 filling level of sight glass N10c (MAX operation) and 1/2 height of sight glass N10b (MIN standstill).
If the oil level is too low, i.e. the oil level has a value
less than 1/2 filling level of sight glass N10b (MIN standstill), oil must be replenished.
10.4.4.5.7 Charging with oil, topping
up with oil
See chapter entitled "Start-up, charging with oil".
Hint!
For permissible types of oil, please
refer to the technical information entitled "Lubricating oils".
Oil removed from the compressor
must not be re-used. Always use fresh
oil from sealed containers! Do not mix
with other types of oil.
10.4.4.6 Oil pump maintenance
Assuming correct installation in accordance with the
conditions of use and correct fitting, gear pumps
have the design prerequisites for long and fault-free
operation.
The gear pumps require a minimum of maintenance
which is, however, indispensable for fault-free operation since experience has shown that a high percentage of the faults and damage which occur are attributable to the ingress of dirt and inadequate maintenance.
The maintenance intervals have been defined in the
maintenance checklist (part of the product documentation).
An oil leakage of up to one drop/minute is required
for the lubrication of the shaft seal and is permissible.
The shaft seal is maintenance-free. If the oil leakage
is too great, replace it according to the oil pump documentation.
Hint!
The regular examination of all operating data, such as pressure, temperature, power consumption, degree of filter fouling, etc., helps in the early
detection of potential failure!
10.4.4.7 Changing the fine oil separation cartridges
The fine oil separation cartridges should be replaced
no later than after 25,000 run hours or 5 years.
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If the oil carry over of the screw compressor package
increases severely (oil recharging at unusually short
intervals), replacement may be necessary even earlier.
fig.48: Operating position of the fine oil separation cartridges
1 Cartridge(s)
2 Fixing cover with O-ring
3 Hexagon-head screw
4 Self-locking hexagon nut
1.
Close the pressure and suction side shut-off fittings.
2.
Drain refrigerant. Evacuate screw compressor
package.
3.
Check the pressure on the display of the control
unit or by connecting a test pressure gauge.
4.
Dismantle the pipe bend after the oil separator.
5.
Dismantle the check valve installed in the oil
separator. This step is omitted if a check valve
which can be shut off is used on the pressure
side.
6.
Remove the self-locking hexagon nut [4].
7.
Loosen the hexagon-head screw [3] and the fixing cover with O-ring [2] for fixing the fine oil separation cartridges.
8.
Remove the cartridge(s) [1].
9.
Mount the new cartridge. The cartridge must be
inserted into the oil separator with the O-ring
first.
Assembly by carrying out steps 1-7 in reverse
order.
Warning!
It is essential to apply self-locking hexagon nut [4] again and secure it
against turning backwards!
max. Tightening torque = 15 Nm
10.4.4.8 Tightening screw fastenings
Screw fastenings of components can become loose
due to vibration or movement. Screw fastenings
must therefore be checked regularly to ensure they
are tight and retightened if necessary.
Screw fastenings must only be tightened to the maximum tightening torques.
Unless otherwise stated by warning signs, the tightening torque is dependent on the size and strength
of the screw fastening.
10.4.4.9 Coupling maintenance
1.
Switch the screw compressor package/ chiller
off.
2.
Secure the electric motor against accidentally
being switched on.
3.
Visually inspect the disk packs.
4.
Check the tightening torques of the fit screws.
5.
Check the alignment of the electric motor and
correct it according to the steel lamination coupling documentation, if required.
6.
Re-grease the coupling (if provided for in the
maintenance instructions for the coupling).
10.4.4.10 Checking the function of check
valves
In order for a check valve to be effective, it is important to perform function checks at regular intervals.
An inspection is carried out by checking the noise
behaviour of the valves during operation. After
switching off the screw compressor package, malfunction on the suction side is indicated by prolonged
turning back of the compressor. Malfunction on the
pressure side leads to an increase of the standstill
pressure in the package to the pressure level of the
system pressure side.
10.4.4.11 Searching for leaks on the
refrigerant side / leak test
The absence of leaks is a precondition for perfect
functioning of the compressor unit/chiller unit. Leaking parts or connecting elements will lead to the loss
of refrigerant and oil as well as the penetration of air
and moisture into the low pressure side. The site of
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the leak must therefore be located and remedied if
there is:
–
Loss of the inert gas charge (delivery state),
–
Loss of the entire refrigerant charge
or
–
underfilling.
Lower refrigerant levels in the containers are due to
loss of refrigerant as a result of leaks. For this reason, all pipes, connections and valve glands should
be checked regularly, especially in the initial period
of assembly.
The most striking feature if there is a leak in the filled
refrigerant circuit is the smell of refrigerant. The
odour threshold of ammonia in the air is approx. 5
ppm and thus well below the permitted MAK values.
Methods of leak detection:
–
Regular visual inspections.
–
Smudges/dirt stains indicate leaking
refrigerant/oil mixture.
–
Leak tests with nitrogen with a max. of 0.5%
ammonia by volume, an elapsed time of more
than 3 hours and application of a foaming agent
to all the joints with a brush. Oil-filled compressors or circuit sections must only be charged
with nitrogen – not air – to generate pressure.
–
Use of an NH3 leak detector.
–
Ammonia produces the following colours when
leak tests are performed:
–
Red litmus paper turns blue,
–
Blotting paper impregnated with phenolphthalein turns red (moisten).
Caution!
Due to the danger of explosion, oxygen must never be used to build up
the pressure!
Generate a test pressure in the refrigerant circuit that
meets the intended operating pressure for the leak
tightness test to determine leaks on the refrigerant
side, e.g. in the case of escaped inert gas or refrigerant. When system parts are individually tested, the
maximum operating pressure indicated on the
respective system part for the corresponding pressure chamber must not be exceeded. The use of
foaming agents gives the best results at test pressures < 5 bar.
If leaks are determined, these must be sealed immediately. Release the test pressure before beginning
repair! Evacuate the system after repairs are complete and after rechecking for leaks.
10.4.4.12
Venting the refrigerant circuit
When air penetrates the refrigerant circuit, this
makes itself felt in a fall-off in performance and the
manometer on the discharge side of the compressor
indicates a higher pressure compared to the condensation temperature. Any leaks must be remedied. In
extreme cases, air in the circuit may interrupt the
flow of refrigerant and cause the oil cooling to fail.
There are several ways of venting the system. The
air or the NH3-air mixture is vented via the vent
valves of the condenser or the suction filter in water
filled vessels when the package is at a standstill.
If air is in the mixture, the venting ammonia is absorbed from water.
Hint!
Continuous venting using a Grasso
purger is recommended.
10.4.4.13 Refrigerant evacuation
Hint!
Shut the oil pump during evacuation!
The purpose of evacuating the system is to remove
air and moisture from the refrigerant circuit.
Evacuation is required:
–
after intervention in the refrigerant circuit and
elimination of leaks,
–
before the start-up/restarting.
Evacuate the screw compressor package using a
vacuum pump. The screw compressor must not be
used for evacuation.
During evacuation, all affected parts of the circuit
should be at room temperature at least because cold
parts hinder the removal of moisture.
If there is still any moisture in the screw compressor
package, this will lead to a rise in pressure. Evacuation must continue until the pressure no longer
increases. A pressure comparison is based on a
constant ambient temperature.
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10.4.4.14 Checking the bearing noise
The bearings of the drive motor and the compressor
must be checked for unusual running noise, especially in comparison to previous maintenance. Recurrent vibration measurements are recommended.
10.4.4.15 Checking the solenoid valves
for capacity control
See the following sections in the start-up chapter:
•
"Checking the control slide adjustment"
•
"Checking the control slide adjustment times"
10.4.4.16 Checking the oil heater
Check the electrical function using a clamp-on
ammeter.
Check the outer temperature of the oil separator and
compare with the temperature of the machine room
(while the screw compressor package is at a standstill).
10.4.4.17 Maintenance of the compressor drive motor
Hint!
The compressor drive motor must be
maintained in accordance with the
"Motor documentation".
Maintenance of the compressor drive motor includes
the following activities:
–
Lubrication of the motor
Lubrication intervals and quantities according to
the "Motor documentation" or "Type plate".
–
Cleaning of the motor (externally)
Select a suitable cleaning agent according to the
"Motor documentation".
10.4.4.18
Checking the start regime
See the operating manual of the compressor control
system.
10.4.4.19 Checking the safety devices
See section entitled "Checking the fault monitoring"
in the start-up chapter.
The safety devices are checked by moving to the
switching points (limiting values). For details, see
also the operating manual of the compressor control
system.
Limiting value = parameter list
Moving to the switching point is achieved by throttling the pressure-side stop valve.
10.4.4.20 Checking the operating parameters
Hint!
The operating parameters are checked via the TouchPanel. The checking intervals recommended in the table must be observed. The project-related setting values and limits are given in
the parameter list.
Inform the manufacturer contract partner if the parameters are outside the allowable limits.
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Parameter to be
checked
Every 24
to 72hrs
Weekly Monthly Remark
Discharge temperature X
Minimum superheat must not be less than 15 K
for NH3. For other refrigerants, the manufactur-
er's instructions must be noted.
Maximum discharge temperature 100°C, in individual cases (e.g. heat pump applications) this
may be exceeded in agreement with the manufacturer.
Oil temperature X
See parameter list!
The viscosity must not be less than 7 cSt at
max. speed (rpm).
Oil pressure X
The oil pressure must be at least 0.5 bar above
the final discharge pressure. An oil pressure
fault may be caused by a clogged oil filter. Setting and monitoring of the values in accordance
with the information in the parameter list.
Discharge pressure X
See project value (parameter list). Determine
the superheat on the pressure side by comparison with the final discharge temperature.
Oil level in oil separator
X
See chapter "Oil level check". An oil level must
be visible in the sight glasses at all times. If the
oil level is below the minimum value, the oil
must be recharged.
Oil heater
X
When compressor is shut down, the heater
must automatically start. Visual check, the
green LED indicates "Voltage ON".
Setting the safety devices
X See set values in the parameter list.
Capacity control
X
Solenoid valves must switch audibly when the
capacity is adjusted. Check in operating mode
"1 (manual + manual)“.
Number of operating
hours
X
See maintenance checklist for maintenance
work to be carried out according to the number
of operating hours.
10.4.4.21 Maintenance of the switching
cabinet
Terminal screws must be checked for tightness and,
if necessary, tightened at regular intervals (every
5,000 operating hours or at least once per year). The
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contacts of the contactors must be checked for loss
of contact material.
10.4.4.22
Checking the earth connection
Check the function of the earth connection frequently
(see the general assembly drawing and the indications on the product).
Only a specialist company must be commissioned
with inspections.
10.4.4.23 Insulation
Check the insulation (if present) on components,
containers and piping for damage.
Damaged insulation must be replaced. The insulation strength must be selected according to the temperature and humidity at the place of installation.
Details on the insulation can be found in the P+I diagram.
Caution!
No screw connections must be used
under the insulation if the piping is
insulated. The pipes must be welded.
10.4.4.24 Check of the tightening torque
on the adjusting elements of
the fixing base.
The tightening torques vary depending on the
strength and size of the screw used. The values for
tightening torques are to be taken from the applicable DIN, unless otherwise specified.
Hint!
The tightening torques for the adjusting elements should be obtained from
the data sheet. The data sheet forms
part of the product documentation.
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11 DECOMMISSIONING
11.1 Shut-down in the event of dangerous situations
The safety equipment of the screw compressor package complies with EN 378.
By means of automatic monitoring of the individual
operating parameters, the control unit detects hazardous situations in good time and automatically
switches off the screw compressor package.
The cause of the fault is displayed on the control unit
and can then be corrected.
Among other things, the concept of the screw compressor packages is based onlow maintenance
refrigerant circuits that are as well sealed as possible. However, residual risks remain, especially due
to possible leaks or escaping refrigerant or rotating
drive parts.
Hint!
The EMERGENCY STOP switch in the
switching cabinet is used to quickly
switch off the chiller whenever necessary.
Leaking refrigerant can be detected with a gas
detector (not included in the scope of delivery). This
detector can be integrated in the automatic safety
chain.
Please consult the safety regulations in this documentation for information about what to do in the
case of leaking refrigerant.
11.2
Standstill for a period <48 hours
Hint!
The obligation to label the plant as
"Plant not in operation" must be
observed!
If the screw compressor package is shut down for a
period <48 hours, the following activities must be
performed:
1.
Switch off the compressor in accordance with the
operating instructions for the electrical switchgear.
2.
If necessary, shut down all ancillary drives.
3.
Switch off the main switch of the three-phase
electric system.
4.
If necessary, shut off the secondary refrigerant,
heating agent or the cooling water supply.
5.
Ensure that the venting slots of the electric
motors are covered under all circumstances!
®
Shut-down has been carried out
11.3
Standstill for a period >48 hours
Hint!
The obligation to label the plant as
"Plant not in operation" must be
observed!
If the screw compressor package is shut down for a
period >48 hours, the following activities must be
performed:
1.
Switch off the compressor in accordance with the
operating instructions for the electrical switchgear.
2.
Switch off all ancillary drives.
3.
Switch off the main switch of the three-phase
electric system.
4.
Close the stop valve (or combined stop/check
valves) on the suction side and the pressure
side.
5.
Close the stop valves (or shuttable check valves)
in the suction line of the economiser.
6.
Shut off the secondary refrigerant, heating agent
or cooling water.
7.
Close the manual stop valve of the refrigerant
injection.
8.
Ensure that the venting slots of the electric
motors are covered under all circumstances!
®
Shut-down has been carried out
11.4
Measures during shutdowns
Even though the screw compressor package/ chiller
is under overpressure, check the moisture content of
the refrigerant and lubricating oil in case it is shutdown for a period longer than half a year. The mois-
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ture content must not differ substantially from the initial values.
11.4.1
Monthly measures during standstill
–
Check that the screw compressor package/
chiller is constantly under overpressure. Check
the screw compressor package/chiller for leaks
using a leak detector.
–
Start the oil pump for approx. 5 minutes.
–
Manually rotate the compressor shaft (min. 10
revolutions).
11.4.2 Four weeks before restarting
–
Check the moisture content and ageing condition
of the refrigerating machine oil. Analyse the oil
for this purpose. Compare the results of the analysis with the values for fresh oil. We recommend
an oil change after 1 year (ammonia as refrigerant) (see Maintenance Instructions).
–
Check the insulation resistance of the drive
motors (see the operating manual for the electric
motor).
–
Switch on the oil pump.
–
Check the screw compressor package/chiller for
leakages.
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
Decommissioning
GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015 85
12 DECOMMISSIONING, DISPOSAL
Preparatory measures
Hint!
The information in the chapter
"Decommissioning" must be
observed.
Hint!
Care must be taken during disposal
and devaluation that the various materials are separated and taken for recycling. Disposal of component remains
and components in the domestic refuge or on refuse tips is not permitted.
The legal regulations applicable to the
place of installation regarding the disposal of electrical equipment must be
taken into account.
Dismantled components must be disposed of correctly and according to
legal requirements.
–
The dismantling and disposal of the package/
chiller must be carried out in such a way that:
•
the plant is free of voltage and is protected
against unintentional reconnection of the
voltage.
•
Accidents to persons are prevented,
•
material damage is prevented,
•
uncontrolled escape of refrigerant or oil is
prevented.
–
Disposal and decommissioning work must only
be carried out by personnel who are qualified
according to EN 13313.
–
Components may be under elevated pressure
and the pressure must be released before opening them.
–
In case of contact with refrigerant or operating
media, their hazardous properties (e.g. toxicity,
inflammability) must be taken into account (see
also the safety data sheet for the refrigerant).
Personal protective equipment compliant with
EN 378-3 must be worn.
–
National regulations (e.g. EN 378-4, Section 6)
must be observed for the reclamation and disposal of refrigerants.
–
National regulations (e.g. EN 378-4, Appendix A)
must be observed for the reclamation and disposal of operating media (oil).
–
No unauthorised persons must be within the
installation area of the plant during decommissioning, as they could come into contact with
refrigerant.
–
All components of the plant which are not to be
re-used, as well as refrigerant and operating
media, must be stored in suitable separate containers. They must be treated as waste and disposed of safely.
Hint!
Re-use of operating media is not possible!
Decommissioning, disposal Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
86 GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
Decommissioning, disposal
GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015 87
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