0772150/6
IM-P077-02
ST Issue 6
S and SF
Inverted Bucket Steam Traps
Installation and Maintenance Instructions
1. Safety information
2. General
product information
3. Installation
4. Commissioning
5. Operation
6. Maintenance
7. Spare parts
IM-P077-02 ST Issue 6 1
© Copyright 2015
Printed in France
1. Safety information
Safe operation of this product can only be guaranteed if it is properly installed,
commissioned, used and maintained by qualified personnel (see Section 1.11 ) in
compliance with the operating instructions. General installation and safety
instructions for pipeline and plant construction, as well as the proper use of tools
and safety equipment must also be complied with.
1.1 Intended use
Referring to the Installation and Maintenance Instructions, name-plate and Technical
Information Sheet, check that the product is suitable for the intended use / application.
The product listed below complies with the requirements of the European Pressure
Equipment Directive 97/23/EC and carries the mark when so required. The product
falls within the following Pressure Equipment Directive categories:
Product
S and SF SEP SEP
i) The product has been specifically designed for use on steam, air or water /
condensate which are in Group 2 of the above mentioned Pressure Equipment
Directive. The products’ use on other fluids may be possible but, if this is
contemplated, Spirax Sarco should be contacted to confirm the suitability of the
product for the application being considered.
ii) Check material suitability, pressure and temperature and their maximum and
minimum values. If the maximum operating limits of the product are lower than
those of the system in which it is being fitted, or if malfunction of the product
could result in a dangerous overpressure or overtemperature occurrence, ensure
a safety device is included in the system to prevent such over-limit situations.
iii) Determine the correct installation situation and direction of fluid flow.
iv) Spirax Sarco products are not intended to withstand external stresses that may
be induced by any system to which they are fitted. It is the responsibility of the
installer to consider these stresses and take adequate precautions to minimise
them.
v) Remove protection covers from all connections before installation.
Group 2
Gases
Group 2
Liquids
1.2 Access
Ensure safe access and if necessary a safe working platform (suitably guarded)
before attempting to work on the product. Arrange suitable lifting gear if required.
1.3 Lighting
Ensure adequate lighting, particularly where detailed or intricate work is required.
1.4 Hazardous liquids or gases in the pipeline
Consider what is in the pipeline or what may have been in the pipeline at some
previous time. Consider: flammable materials, substances hazardous to health,
extremes of temperature.
IM-P077-02 ST Issue 62
1.5 Hazardous environment around the product
Consider: explosion risk areas, lack of oxygen (e.g. tanks, pits), dangerous gases,
extremes of temperature, hot surfaces, re hazard (e.g. during welding), excessive
noise, moving machinery.
1.6 The system
Consider the ef fect on the complete system of the work proposed. Will any proposed
action (e.g. closing isolation valves, electrical isolation) put any other part of the
system or any personnel at risk?
Dangers might include isolation of vents or protective devices or the rendering
ineffective of controls or alarms. Ensure isolation valves are turned on and off in a
gradual way to avoid system shocks.
1.7 Pressure systems
Ensure that any pressure is isolated and safely vented to atmospheric pressure.
Consider double isolation (double block and bleed) and the locking or labelling of
closed valves. Do not assume that the system has depressurised even when the
pressure gauge indicates zero.
1.8 Temperature
Allow time for temperature to normalise after isolation to avoid danger of burns.
1.9 Tools and consumables
Before starting work ensure that you have suitable tools and /or consumables
available. Use only genuine Spirax Sarco replacement parts.
1.10 Protective clothing
Consider whether you and/or others in the vicinity require any protective clothing
to protect against the hazards of, for example, chemicals, high / low temperature,
radiation, noise, falling objects, and dangers to eyes and face.
1.11 Permits to work
All work must be carried out or be supervised by a suitably competent person.
Installation and operating personnel should be trained in the correct use of the
product according to the Installation and Maintenance Instructions.
Where a formal ‘permit to work’ system is in force it must be complied with. Where
there is no such system, it is recommended that a responsible person should know
what work is going on and, where necessar y, arrange to have an assistant whose
primary responsibility is safety.
Post ‘warning notices’ if necessary.
1.12 Handling
Manual handling of large and/or heavy products may present a risk of injury. Lifting,
pushing, pulling, carrying or supporting a load by bodily force can cause injury
particularly to the back. You are advised to assess the risks taking into account the
task, the individual, the load and the working environment and use the appropriate
handling method depending on the circumstances of the work being done.
IM-P077-02 ST Issue 6 3
1.13 Residual hazards
In normal use the external surface of the product may be very hot. If used at the
maximum permitted operating conditions the surface temperature of some products
may reach temperatures in excess of 425°C (797°F).
Many products are not self-draining. Take due care when dismantling or removing
the product from an installation (refer to ‘Maintenance instructions’).
1.14 Freezing
Provision must be made to protect products which are not self- draining against frost
damage in environments where they may be exposed to temperatures below freezing
point.
1.15 Disposal
Unless otherwise stated in the Installation and Maintenance Instructions, this
product is recyclable and no ecological hazard is anticipated with its disposal
providing due care is taken.
1.16 Returning products
Customers and stockists are reminded that under EC Health, Safety and Environment
Law, when returning products to Spirax Sarco they must provide information on
any hazards and the precautions to be taken due to contamination residues or
mechanical damage which may present a health, safety or environmental risk. This
information must be provided in writing including Health and Safety data sheets
relating to any substances identified as hazardous or potentially hazardous.
1.17 Working safely with cast iron products on steam
Cast iron products are commonly found on steam and condensate systems. If
installed correctly using good steam engineering practices, it is perfectly safe.
However, because of its mechanical properties, it is less forgiving compared to other
materials such as SG iron or carbon steel. The following are the good engineering
practices required to prevent waterhammer and ensure safe working conditions on
a steam system.
Safe Handling
Cast Iron is a brittle material. If the product is dropped
during installation and there is any risk of damage the
product should not be used unless it is fully inspected and
pressure tested by the manufacturer.
IM-P077-02 ST Issue 64
Prevention of water hammer
Steam trapping
on steam mains:
Steam
Steam Mains - Do's and Don'ts:
30 - 50 metre intervals
Gradient 1:100
Trap set
Condensate
Gradient 1:100
Trap set
Condensate
Steam
Trap set
Condensate
Steam
Flow
Steam
Flow
IM-P077-02 ST Issue 6 5
Prevention of tensile stressing
Pipe misalignment:
Installing products or re-assembling after maintenance:
Do not over tighten.
Use correct torque gures.
Thermal expansion:
Guides
Short
distance
1
4 2
Flange bolts should be gradually tightened across
diameters to ensure even load and alignment.
Fixing point
3
Axial
movement
7
3
6
2
Axial movement
1
5
4
8
Medium
distance
Guides
Guides
Limit
rods
movement
Fixing point
Limit rods
Guides
Small
lateral
Large
lateral
movement
Small
lateral
movement
Large
lateral
movement
IM-P077-02 ST Issue 66
2. General product information
2.1 Description
The S series is a maintainable cast iron inverted bucket steam trap with screwed in-line
connections and integral strainer. The SF series has integral flanged connections and integral
st raine r.
Note: For additional information see the following Technical Information Sheet: TI-P077-01.
2.2 Sizes and pipe connections
½" - SA, ¾" - SB, 1" - SC, 1½" - SD Screwed BSP, ISO 7/1 Rp.
DN15 - SFA, DN20 - SFB, DN25 - SFC, DN40 - SFD.
Standard flange BS 4504 / DIN 2501 PN16 (UNI 2237 / 2229).
Fig. 1
¾" Screwed S series
Fig. 2
DN25 Flanged SF series
IM-P077-02 ST Issue 6 7
2.3 Limiting conditions (ISO 6552)
Note: Maximum operating conditions depend on the selected orifice size.
Body design conditions PN16
PMA Maximum allowable pressure 16 bar g (232 psi g)
TMA Maximum allowable temperature 300°C (572°F)
PMO Maximum operating pressure 13 bar g (188.5 psi g)
TMO Maximum operating temperature 300°C (572°F)
Designed for a maximum cold hydraulic test pressure of: 24 bar g (348 psi g)
2.4 Operating range
Steam
saturation
Temperature °C
The product must not be used in this region.
*PMO Maximum operating pressure 13 bar g (188.5 psi g).
curve
Pressure bar g
∆ PMX - Maximum differential pressure
Screwed 4 bar 8 bar 12 bar Flanged 4 bar 8 bar 12 bar
½" SA4 SA8 SA12 DN15 SFA 4 SFA8 SFA12
¾" SB4 SB8 SB12 DN20 SFB4 SFB8 SFB12
1" SC 4 SC8 SC12 DN25 SFC4 SFC8 SFC12
1½" SD4 SD8 SD12 DN40 SFD4 SFD8 SFD12
2.5 Materials of construction
The S and SF series inverted bucket traps are manufactured in cast iron with stainless steel
internals.
IM-P077-02 ST Issue 68
3. Installation
Note: Before actioning any installation obser ve the 'Safety information' in Section 1.
Referring to the Installation and Maintenance Instructions, name-plate and Technical
Information Sheet, check that the product is suitable for the intended installation.
3.1 Check materials, pressure and temperature and their maximum values. If the maximum
operating limit of the product is lower than that of the system in which it is being fitted,
ensure that a safety device is included in the system to prevent overpressurisation.
3.2 Determine the correct installation situation and the direction of fluid flow.
3.3 Remove protective covers from all connections.
3.4 The trap must be installed with the body upright so that the bucket is rising and falling
vertically. When superheat conditions exist the trap body may need to be primed with
water prior to steam being turned on to avoid steam blowing through the trap.
3.5 Inver ted bucket steam traps do not permit rapid release of air. On process applications,
in particular, this can lead to slow warm-up times and waterlogging of the steam space.
A separate external air vent is therefore required in parallel to vent air efficiently. Any
bypass should be positioned above the trap. If it is below, and is leaking or left open,
the waterseal could be blown away leading to steam wastage. Where inver ted bucket
traps are fitted in exposed conditions the possibility of freezing damage can be reduced
by thermal insulation.
3.6 Traps must be installed in a horizontal pipeline. The inlet of the trap should be
below the drain point of the plant being drained, so that a waterseal can be maintained
around the open end of the bucket. A small drop leg should preceed the trap - typically
150 mm (6").
3.7 Where the trap discharges into a closed condensate return system or where there is
a lift at the trap, a check valve should be fitted downstream of the trap.
3.8 If the trap has to be installed at a higher point than the drainage point then a small
bore riser into a 'U' seal should be used. A check valve should be fitted before the
trap to prevent the loss of the internal waterseal.
3.9 If the trap has to be installed on a superheated steam system application, then a non
return valve should be fitted on the trap inlet, to prevent the trap from losing its
waterseal.
Priming of the trap with water may be required before commissioning.
3.10 When welding the trap into the pipeline, this should be carried out by the electric arc
process. If it is installed in exposed positions, considerations should be given to
insulating the trap.
Note: If the trap is to discharge to atmosphere ensure it is to a safe place, the discharging
fluid may be at a temperature of 100°C (212°F).
4. Commissioning
After installation or maintenance ensure that the system is fully functioning. Carry out tests
on any alarms or protective devices.
IM-P077-02 ST Issue 6 9
5. Operation
Under most conditions the trap will discharge condensate with a blast type action. Under
low load and/or low pressure applications the discharge may tend to 'dribble'. Condensate
is discharged at steam temperature so due care must be given to the site of the discharge.
6. Maintenance
Note: Before actioning any maintenance programme observe
the 'Safety information' in Section 1.
Warning
The body/cover gasket and strainer cap gaskets contain a thin stainless steel
suppor t ring which may cause physical injury if not handled and disposed of
carefully.
6.1 General information
Before undertaking any maintenance on the trap it must be isolated from both the supply line
and return line and any pressure allowed to safely normalise to atmosphere. The trap should
then be allowed to cool. When reassembling, ensure that all joint faces are clean.
6.2 How to fit the valve and seat assembly (refer to Fig. 3):
- Undo the cover bolts and nuts and remove the cover from the body.
- Unhook the bucket from the valve lever.
- Remove the valve guide plate by undoing the two screws.
- Remove the seat from the cover.
- Ensure all jointing faces are clean and then screw in the new seat to the recommended
torque (see Table 1). Use a small amount of jointing paste on the threads.
- Fit a new valve guide plate with t wo screws supplied and refit the new lever. Ensure that
the valve and seat are aligned correctly before finally tightening the guide plate screws.
- Hook the bucket to the lever and ensure gasket faces on the body cover are clean.
- Using a new cover gasket refit the cover to the body ensuring the small ferrule is positioned
correctly. Tighten the cover bolts/nuts to the recommended torque (see Table 1).
6.3 How to clean/replace the strainer screen (refer to Fig. 3):
- Undo the strainer cap and remove the screen and gasket.
- Clean or replace the strainer screen.
- Ensure threads are clean.
- Refit a new strainer cap gasket and locate the screen in the strainer cap.
- Screw into the body and tighten to the recommended torque (see Table 1).
IM-P077-02 ST Issue 610
Table 1 Recommended tightening torques
17
3
Item Size
½" - DN15 15 - 25 - 30 (19 - 22)
¾" - DN20 17 - 35 - 40 (26 - 30)
3
1" - DN25 22 - 50 - 60 (37 - 45)
1½" - DN40 30 - 80 - 90 (59 - 67)
½" - DN15 30 - 50 - 60 (37 - 45)
¾" - DN20 36 - 50 - 60 (37 - 45)
10
1" - DN25 46 - 70 - 80 (52 - 59)
1½" - DN40 50 - 90 - 110 (67 - 81)
½" - DN15 - M4 x 8 2.5 - 3 (2.0 - 2.2)
¾" - DN20 - M5 x 10 3 - 4 (2.2 - 3.0)
16
1" - DN25 - M5 x 10 3 - 4 (2.2 - 3.0)
1½" - DN40 - M6 x 10 5 - 6 (3.7 - 4.4)
½" - DN15 - M8 x 20 20 - 25 (15 - 19)
¾" - DN20 - M12 x 25 60 - 70 (45 - 52)
17
1" - DN25 - M10 x 30 40 - 45 (30 - 34)
or
mm
N m (lbf ft)
1½" - DN40 - M12 x 35 60 - 70 (45 - 52)
16
10
Fig. 3
IM-P077-02 ST Issue 6 11
7. Spare parts
The spare parts available are shown in heavy outline. Parts shown in broken lines are not
supplied as spares.
Available spares
Valve and seat assembly 3, 4, 5, 6, 7, 12, 13, 14*, 16*, 19, 20*
Bucket assembly 8
Strainer screen 9, 11
Packet of gaskets 7, 11, 12, 13
*(2 off)
How to order spares
Always order spares by using the
description given in the column head
'Available spares' and state the size,
model No. and presure rating of the trap.
Example: 1 - Valve and seat assembly
for Spirax Sarco DN20 SFB8 inverted
bucket steam trap for differential
pressures up to 8 bar.
5
14
16
17
12
13
3
6
4, 19
20
Fig. 4
8
7
9 11 10
IM-P077-02 ST Issue 612
Loading...