Graham PV31120, PV31040, PV31080, PV41160, PV51120 Installation, Operation & Maintenance Manual

Liquid Ring Pump

IOM-LRP1,2_0402

Series 1 and 2 Design

INSTALLATION, OPERATION & MAINTENANCE MANUAL

Graham Corporation ● 20 Florence Avenue ● Batavia, New York 14020

Email: [e-mail] ● www.graham.mfg.com

Phone: [phone] ● Fax: [phone]

Graham Corporation

Table of Contents

Section 1 - General Information...........................................................................3

1.1 Introduction....................................................................................................................... 3

1.2 General Description and Principle of Operation ........................................................... 4

1.3 Description of Pump Model Codes ..................................................................................5

Section 2 - Installation Instructions .....................................................................6

2.1 Handling............................................................................................................................. 6

2.2 Preservation....................................................................................................................... 6

2.3 Mounting............................................................................................................................ 6

2.4 Installation ......................................................................................................................... 6

2.5 Coupling Alignment..........................................................................................................7

2.6 Belt Drives.......................................................................................................................... 8

2.7 Service Liquid Piping Arrangements.............................................................................. 8

2.8 Shaft Seal Coolant Piping Arrangement....................................................................... 11

2.9 Piping Requirements....................................................................................................... 14

2.10 Electrical Requirements ............................................................................................... 14

Section 3 - Operating Instructions .....................................................................15

3.1 Start-up Procedures........................................................................................................ 15

3.2 Pump Packing Adjustment ............................................................................................15

3.3 Service Liquid Requirements......................................................................................... 16

3.4 Cavitation......................................................................................................................... 17

3.5 Shut-Down Procedures ...................................................................................................17

Section 4 - Accessory Items .................................................................................18

4.1 Accessories ....................................................................................................................... 18

Section 5 - Maintenance ......................................................................................20

5.1 Performance ....................................................................................................................20

5.2 Series 1 and 2 Pump Estimated Weights ( lbs.)*.......................................................... 20

5.3 Shaft Bearings .................................................................................................................21

5.4 Gland Packings................................................................................................................ 21

5.5 Mechanical Seals ............................................................................................................. 22

5.6 Storage.............................................................................................................................. 22

5.7 Removal from storage..................................................................................................... 23

5.8 Troubleshooting Chart ...................................................................................................24

Section 6 - Disassembly And Reassembly Procedures .....................................25

6.1 General............................................................................................................................. 25

6.2 Impeller End Clearances ................................................................................................25

6.3 Tie Rod Torque Values................................................................................................... 27

6.4 Bearing Data.................................................................................................................... 27

Section 7 - Warranty............................................................................................28

Appendix A- MATERIAL SAFETY DATA SHEET .......................................29

Appendix B- RETURN MATERIAL AUTHORIZATION FORM................33

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Section 1 - General Information

1.1 Introduction

This manual will provide assistance in the installation, operation, and maintenance of your
Graham Liquid Ring Pump. Please read this manual completely prior to operating your Liquid
Ring Pump. If you need to contact the Pump Service department for assistance, please have
available the pump serial number, model number, and ID number if possible. The ID number is
stamped on the edge of the discharge flange. The Pump Service department may be reached by
contacting Graham Corporation in Batavia, NY by phone [phone], Fax [phone],
or e-mail at

Graham has an extensive stock of spare parts and replacement pumps. Stocked parts and pumps
can be shipped from our warehouse in Batavia, NY by a carrier of your choice.

For your convenience, use our toll free number ( 1-800-828-8150 ) only when ordering spare
parts and replacement pumps. Please have the model number, serial number and part number of
the items required when placing an order. Normal business hours are 8:00 a.m. to 5:00 p.m.
(E.S.T.), Monday through Friday.

Factory rebuilding service is available for pumps returned to Batavia. When a pump is returned
to the factory for repairs, please drain and flush the pump and include a Material Safety Data
Sheet (MSDS) (see Appendix A) for the process in which the pump was used. A Return
Material Authorization (RMA) Number (see Appendix B), issued by Graham, is required
before returning a pump. A sample form is included at the back of this manual to show what
type of information is required to obtain an RMA Number. Field Service Technicians are also
available for travel to the jobsite for troubleshooting and repair or rebuilding of pumps.

This document and the information contained herein are the property of Graham Corporation
and must not be copied, in whole or in part, nor used for manufacture or otherwise disclosed
without the prior written consent of the company. Information contained herein may, from time
to time, be revised and/or updated. Copyright Graham Corporation 1999

[e-mail]

.

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1.2 General Description and Principle of Operation

Graham Vacuum Pumps and Compressors are of the liquid ring type. Single and two stage
pumps are available in a wide range of sizes and materials. These options are listed in the
Graham Sales Bulletins. The major component of the Graham pump is a multi-bladed rotating
assembly positioned eccentrically in a cylindrical casing. (See Figure 1) This assembly is
driven by an external source, normally an electric motor. Service liquid (usually water) is
introduced into the pump. As the impeller rotates, centrifugal force creates a liquid ring which
is concentric to the casing. At the inlet, the area between the impeller blades (buckets) increase
in size, drawing gas in. As the impeller continues to rotate toward the discharge, the impeller
bucket area decreases in size, compressing the gas. This gas, along with the liquid from the
pump, is discharged through the outlet nozzle. The service liquid is separated from the gas and
cooled for reuse in the pump or sent to a drain. In addition to being the compressing medium,
the liquid ring performs two other important functions:

1) It absorbs the heat generated by compression, friction, and condensation of
the incoming vapor.

2) It absorbs and washes out any process contaminants entrained in the gas.

A continuous supply of service liquid is necessary to limit the temperature rise in the pump
caused by the heat of compression, friction, and condensation. Any excessive rise in
temperature will have a detrimental effect on performance, reducing the capacity and degree of
vacuum attainable. Installation schematics for the supply of the service liquid and for the
separation of the gas and liquid discharged from the pump are shown in Section 2.

Gas and

Liquid Outlet

Gas

Inlet

Rotation

Liquid Ring

Shaft

Discharge Port

Suction Port

Gas

Impeller

Figure 1

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Service liquid quantities are a function of the particular model and the intended application.
Check the data sheet for your specific pump model or see Table 1 of Section 3 which lists
typical service liquid requirements.

The normal operating ranges of Liquid Ring Pumps when using water at 59º F
(15 ºC) for the service liquid are:

Single Stage Pumps down to 150 mmHgA
Two Stage Pumps down to 25 mmHgA
Two Stage Pumps w/Air Ejector down to 3 mmHgA
Single Stage Compressors 20 psi (1.4 bar) max. differential
Two Stage Compressors 30 psi (2.1 bar) max. differential

The standard materials of construction are suitable for handling air and other non-corrosive
gases, while using water as the service liquid. Other materials can be supplied for special
applications.

1.3 Description of Pump Model Codes

Each pump is designated by a model code which describes the materials of construction, size,
type of shaft seals, and any special features. An example of a typical pump is shown below.
Contact Graham for a complete listing of the codes used to describe the pump.

Number of Stages

Impeller Size

Frame Size

Pump Series

Shaft Seal Code

Special Features

2 PV 42120 / 12 / 43 / I / D

Vacuum Pump = PV
Compressor = PC

Pump

Material

Code

Connection
and Shaft
End Type

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Section 2 - Installation Instructions

2.1 Handling

Carefully unpack the pump. Bare pumps may be lifted with a sling placed around the bearing
housings or under the flanges.

Lift pump-motor assemblies by the baseplate only. Do not attach slings nor hooks to the motor
or the pump as this can cause misalignment. Do not attempt to run the pump until the
installation work is complete.

CAUTION: DO NOT RUN THE PUMP WITHOUT SERVICE LIQUID AND SHAFT
SEAL FLUID.

2.2 Preservation

Cast Iron and Steel pumps are protected internally with a preservative solution applied at the
factory before shipping. The solution should be flushed from the pump prior to use. An MSDS
form is included in the back of this manual (see Appendix A).

The preservative solution is petroleum based and must be disposed of

in accordance with all Local, State, and Federal regulations.

2.3 Mounting

Before operation, the pump package should be carefully set, leveled, and securely bolted in
place. It is recommended that shims and grout be used as necessary under all structural
members of the base.

Graham size 30000 through 50000 vacuum pump assemblies are available with an adapter for
mounting a “C-Face” motor. The pump and support bracket should be bolted to the floor, a
cement pad, or an existing framework.

Baseplates supplied with a pump and drive motor mounted at the factory should be leveled,
shimmed as required, and firmly anchored.

2.4 Installation

All piping to the pump should be adequately supported to eliminate any stress at the pump
connections. All piping joints should be tested for leaks prior to start-up. A temporary start-up
strainer in the process inlet piping may be used to keep large contaminates from entering the
pump at start-up.

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Install the piping for the shaft seal coolant as required. Refer to section 2.8 regarding the shaft
seal coolant piping requirements.

The location of the installation or the storage of the pump should be in an area that will
not subject the pump to freezing.

Verify the pump’s rotation direction by checking the arrow on the shaft end casing. Refer to
section 2.10 concerning the electrical requirements.

2.5 Coupling Alignment

CAUTION:

Pumps supplied from the factory packaged with a motor have had the shafts aligned prior to
shipment. This ensures that alignment can be done in the field. It is required that the shaft
alignment be rechecked after mounting on a level foundation and prior to start-up.

When a gear reducer is supplied between the pump and motor, they are aligned at the factory
and must be realigned after installation. The gear reducer should be aligned to the pump first
and then the motor should be aligned to the gear reducer.

For smoother operation and longer life of the coupled equipment, the following maximum
misalignment tolerances are recommended:

The maximum allowable parallel shaft misalignment for standard couplings is
±0.002" (0.05 mm) and for spacer couplings is ±0.001" per inch (0.025 per mm) of
spacer length.

The maximum allowable angular shaft misalignment is ±0.0005" per inch
(0.013 per mm) of coupling diameter.

TO PREVENT PERSONAL INJURY, DO NOT OPERATE THE PUMP

WITHOUT PROPERLY GUARDING THE DRIVE COUPLING(S).

±0.002" or
±0.001" x L

L

D

±0.0005" x D

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2.6 Belt Drives

CAUTION:

When pumps are supplied with belt drives, follow the belt manufacturer’s instructions to set the
tension.

TO PREVENT PERSONAL INJURY, DO NOT OPERATE THE
PUMP WITHOUT PROPERLY GUARDING THE DRIVE BELTS.

2.7 Service Liquid Piping Arrangements

The operating principle of a liquid ring pump depends on a continuous supply of clean service
liquid, which is normally water. The liquid enters the pump through a connection on the casing
and is discharged from the pump along with the gas. There are two basic piping arrangements
that can be used for liquid ring pump applications. A once-through method with no recovery of
the service liquid and a recirculation method which re-uses the service liquid.

Both of these arrangements have four basic elements:

1) A supply of service liquid.

2) A means to control flow of service liquid.

3) A means of stopping the flow of service liquid when the pump is off.

4) A means of separating the gas / liquid exhaust mixture.

It is recommended to use a strainer to ensure that foreign matter does not enter the pump with
the service liquid supply or make-up source. See Diagrams 1 and 2 for the proper piping
arrangement scheme.

CAUTION: COMPLETE ALL PIPING INSTALLATION AND MAKE SURE A

SUPPLY OF SERVICE LIQUID IS AVAILABLE BEFORE
STARTING THE PUMP.

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A) Typical Installation of Once Through with No Recovery

The service liquid is piped directly from a supply source to the pump. The liquid is separated
from the gas in the separator and discharged to a drain. No recirculation nor recovery takes
place. This is the most basic arrangement and can be used when service liquid conservation or
contamination is not a concern. A solenoid operated valve provides for flow of the liquid
simultaneously with the pump/motor operation. When the motor stops, the valve closes to
prevent the pump casing from filling with fluid. The by-pass valve is used to pre-fill the pump
at initial start-up only. It also can be used should the solenoid fail. When a manual valve is
used, it must be opened immediately after starting the motor and closed immediately before
turning the motor off.

D

A

B

C

Gas

Outlet

Process
Inlet

E

Service
Liquid Inlet

S

Liquid

Drain

F G H

J K

L

M

A- Inlet Check Valve G- Shut-off Valve

B- Pressure Gauge

service or compound gauge for compressor
service)

Vacuum Relief Valve

C-

compressor service)

Separator

D-

(vacuum gauge for vacuum

(not required for

H-

L-

Regulating Valve
Solenoid Valve

J-

Compound Gauge

K-

Liquid Ring Pump

M-

Trap

(required if discharge pressure

is above atmospheric pressure)

E- By-Pass Valve

F- Strainer

Once Through with No Recovery

Diagram 1

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N

B) Typical Installation of Closed Loop with Total Recovery

This arrangement provides for the total recirculation of the service liquid. A heat exchanger is
added to the system to remove the heat of compression, friction, and condensation from the
service liquid before it is re-introduced to the pump.

The service liquid level in the separator of a total recovery system should be at or slightly
below the centerline of the pump shaft. A provision should be made for a high level overflow.
This will prevent starting the pump while it is full of liquid, which will damage the pump or
overload the motor.

D

A

B

C

E

Process
Inlet

Gas

Outlet

F

G H

LG

Cooling
Liquid Inlet

J

K

Cooling
Liquid

Drain Make-up

L

Overflow

M

A- Inlet Check Valve G- Shut-off or Throttling Valve

B- Pressure Gauge

service or compound gauge for compressor
service)

Vacuum Relief Valve

C-

compressor service)

Level Gauge

D-

(vacuum gauge for vacuum

(not required for

H-

L-

Compound Gauge
Liquid Ring Pump

J-

Recirculation Pump (recommended)

K-

Trap or Loop Seal

charge pressure is above atmospheric
pressure)

(required if dis-

E- Separator M- Drain Valve

F- Service Liquid Cooler N- Make-Up Valve

Closed Loop-Total Recovery

Diagram 2

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