Graham Corporation Liquid Ring Pump 2 Series Instruction manual

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 ...................................................................................................................... 11
2.10 Electrical Requirements ............................................................................................................... 12
Section 3 - Operating Instructions .............................................................................................. 12
3.1 Start-up Procedures ........................................................................................................................ 12
3.2 Pump Packing Adjustment............................................................................................................. 13
3.3 Service Liquid Requirements......................................................................................................... 14
3.4 Cavitation ....................................................................................................................................... 15
3.5 Shut-Down Procedure .................................................................................................................... 16
Section 4 - Accessory Items........................................................................................................ 16
4.1 Accessories..................................................................................................................................... 16
Section 5 - Maintenance.............................................................................................................. 19
5.1 Performance ................................................................................................................................... 19
5.2 Pump Estimated Weights ............................................................................................................... 19
5.3 Shaft Bearings ................................................................................................................................ 19
5.4 Gland Packings .............................................................................................................................. 19
5.5 Mechanical Seals............................................................................................................................ 19
5.6 Storage ........................................................................................................................................... 20
5.7 Removal from storage.................................................................................................................... 20
5.8 Troubleshooting Chart ................................................................................................................... 21
Section 6 - Rebuild Instructions.................................................................................................. 22
6.1 General ........................................................................................................................................... 22
6.2 Impeller End Clearances ................................................................................................................ 22
6.3 Tie Rod Torque Values .................................................................................................................. 24
6.4 Bearing Data .................................................................................................................................. 24
Section 7 - Warranty ................................................................................................................... 25
Appendix A- Material Safety Data Sheets.................................................................................. 26
Appendix B- Return Material Authorization Form .................................................................... 29
Appendix C- Pump Information ................................................................................................. 30
Appendix D- Pump Weights....................................................................................................... 31

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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 and model number. The Pump Service Department may be
reached by contacting Graham Corporation in Batavia, NY by phone [phone], Fax (585)
343-1097, or e-mail at [e-mail]. Refer to the Graham web site at
www.graham-mfg.com for other information on our Liquid Ring Pumps.
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. Refer to Graham web site www.graham-mfg.com for
Liquid Ring Vacuum Pump spare parts information. 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 our factory in Batavia, New York.
Before a pump is returned to the factory for repairs, please drain and flush the pump and include
a Material Safety Data Sheet (MSDS) for the process in which the pump was used. A Return
Material Authorization (RMA) Number, issued by Graham, is required before returning a pump.
Refer to our web site for this form or contact Graham for this information. Field Service
Technicians are also available for travel to the jobsite for troubleshooting and repair or
rebuilding of pumps. Contact Graham for service rates.
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 2006

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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 Bulletin available on our web site. 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) increases 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.
FIGURE 1
Shaft
Suction Port
Impeller
Gas
Dischar
g
e Port
Li
q
uid Rin
g
Gas and
Li
q
uid Outlet
Gas
Inlet
Rotation

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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 for Graham Model Pumps.
The normal operating ranges of Liquid Ring Pumps when using water at 59 ºF
(15 ºC) for the service liquid are:
Single Stage Pumps dependent on model, down to 25 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.
Note: Graham Pump Models LXP30 & LXP55 are replacements for models 2PV31020 and
2PV31040 respectively.
Number of Stages
Frame Size
Series 2 Design
Size
C-faced mounting option
(not available on all models)
2 PV 42120 / 10 / DD / L
Design CodeVacuum Pump = PV Material
C
ode

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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 or 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 preservative solution should be flushed from the pump prior to use.
An MSDS form is included in the back of this manual (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 vacuum pumps supplied with an adapter for mounting a NEMA C-faced motor should
be bolted to a floor, a cement pad or an existing framework. Support bracket located under
motor lantern should contact but not be anchored to the floor or mounting base.
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 service liquid and process, as required. Refer to Section 2.7 for details.
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: TO PREVENT PERSONAL INJURY, DO NOT OPERATE THE PUMP
WITHOUT PROPERLY GUARDING THE DRIVE COUPLING(S).
Pumps supplied from the factory packaged with a motor on a baseplate 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.
Pumps provided with a C-faced mounted motor do not require alignment, however, the coupling
should be checked prior to start-up.
±0.002"or
±0.001"x L
L
D
±0.0005"x D

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2.6 Belt Drives
CAUTION:
TO PREVENT PERSONAL INJURY, DO NOT OPERATE THE PUMP
WITHOUT PROPERLY GUARDING THE DRIVE BELTS.
When pumps are supplied with belt drives, follow the belt manufacturer’s instructions to set the
tension.
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.
A. Inlet Check Valve G. Strainer
B. Pressure Gauge (vacuum gauge for
vacuum service or compound gauge for
compressor service)
H.
J.
K.
Regulating Valve
Solenoid Valve
Compound Gauge
C.
D.
Vacuum Relief Valve (not required for
compressor service)
Discharge Separator
L.
M.
Liquid Ring Pump
Trap (required if discharge pressure
is above atmospheric pressure)
E. By-Pass Valve
F. Shut-off Valve
ONCE THROUGH WITH NO RECOVERY
DIAGRAM 1
Process
Inlet
Service
Liquid Inlet
Gas
Outlet
Liquid
Drain
S
A D
F G H
E
J K
C
B
ML

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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.
A. Inlet Check Valve G. Shut-off or Throttling Valve
B. Pressure Gauge (vacuum gauge for
vacuum service or compound
gauge for compressor service)
H.
J.
K.
Compound Gauge
Liquid Ring Pump
Recirculation Pump (if required)
C.
D.
Vacuum Relief Valve (not required
for compressor service)
Level Gauge
L. Trap or Loop Seal (required if dis-
charge pressure is above atmospheric
pressure)
E. Discharge Separator M. Drain Valve
F. Service Liquid Cooler N. Make-Up Valve
CLOSED LOOP-TOTAL RECOVERY
DIAGRAM 2
A
E
B DC
LG
Process
Inlet
Cooling
Liquid Inlet
Cooling
Liquid
Gas
Outlet
Overflow
Make-upDrain
F
K
HG
M N
J
L

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C) Draining Before Start-Up
CAUTION: DO NOT START THE PUMP WITH THE CASING FULL OF LIQUID.
A Liquid Ring Pump should not be started with the casing full of liquid. Damage to the
impeller(s) or the shaft will result. The normal liquid level should be no higher than the shaft
centerline. The pump may be started with a low liquid level as long as a supply of service liquid
is available immediately after start-up.
2.8 Shaft Seal Coolant Piping Arrangement
The Graham model Liquid Ring Vacuum Pumps incorporate internally flushed mechanical seals
as a standard. Models that have been supplied fitted with special seal arrangements may require
external flushing. Consult the factory for details.
2.9 Piping Requirements
A) Suction and Discharge Piping
The suction and discharge flanges on the pump are arranged vertically and are marked with arrows
on the pump casing. The suction and discharge piping should be the same nominal size as the
pump flanges. The elevation of the discharge separator above the discharge flange should be
limited to an elbow turning horizontally.
If necessary, a discharge leg can be used with a maximum of 24 inches (610 mm) above the
pump discharge flange. Too high an elevation in this line will cause excessive backpressure on
the pump, overload the motor, and reduce the pump capacity.
Remove the protective coverings from the pump openings just before attaching the piping. Check
that all foreign matter such as weld slag, nuts, bolts, rags, and dirt has been cleaned out of the
piping before connecting to the pump. The piping flanges must fit easily and without strain on the
pump flanges and the flange bolt holes must be in alignment. The flange gaskets must not
protrude into the bore of the piping or pump flanges. All piping must be supported independently
on each side of the pump without transmitting any strain to the pump casing. A temporary suction
strainer fitted at the suction inlet is recommended during the first 100 hours of operation.
B) Service Liquid Piping
In a once-through arrangement, the nominal pipe size should be the same size as the service liquid
connection. In a total recirculation package with no recirculation pump, use one nominal pipe
size larger than the service liquid connection of the pump. Also, use the least number of fittings
to minimize the pressure drop. When a recirculation pump is used, the piping should be the same
size as the service liquid connection.

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2.10 Electrical Requirements
All electrical wiring and installation must comply with local safety codes. After the electrical
work is complete, the motor should be jogged to check for proper rotation. First, turn the
pump by hand to see that it rotates freely. On packed gland pumps, it may be necessary to
loosen the gland packing rings (see Section 3.2) to allow the shaft to turn easily. The direction
of rotation is marked on the pump. Second, jog the motor momentarily to check the rotation. It
is recommended to use a non-reversing motor controller to prevent the pump from turning in
the wrong direction.
Section 3 - Operating Instructions
3.1 Start-up Procedures
Read all instructions before proceeding.
1) Turn the shaft manually to ensure it rotates freely. If the pump is binding or seized,
refer to the troubleshooting chart in Section 5.
2) Fill the pump with service fluid to the shaft centerline, but do not overfill.
CAUTION: DO NOT RUN THE PUMP WITHOUT SERVICE LIQUID
AND SHAFT SEAL FLUID.
3) The normal service liquid level should be no higher than the shaft centerline. The
pump may be started with a low service liquid level as long as a supply is available
immediately after start-up.
4) Open any valves in the suction and discharge lines.
5) Confirm the pump rotation with the arrow on the casing by jogging the motor.
6) Start the motor, ensure service liquid supply, and set regulating valve, when used, for
optimum pump performance. Open and adjust the shaft seal cooling liquid valve,
when used.

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3.2 Pump Packing Adjustment (where applicable)
The packing adjustment nuts should be loosened before running to prevent damage to the shaft.
With the gland follower loosened, the liquid pressure in the glands will force the packing rings
against the gland follower. The pump can be run for several hours in this manner. Tighten the
gland follower to allow the cooling fluid to drop from the gland at a rate of about 20 drops per
minute from each end while the pump is running at a steady state.
Pump Shaft
Packing Adjustment Nuts
Gland Packing
Gland Follower
ONE END OF PUMP SHOWN

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3.3 Service Liquid Requirements
A) Flow Rates
Sealant water flow rate will vary based on what conditions the liquid ring pump is operating
under. Table 1 provides information for most operating conditions. Sealant flow is considered
acceptable when the required vacuum level is at design, motor amps are at design, and cavitation
is not evident during pump operation.
Graham Liquid Ring Pump Sealant Water Flow Rates
Pump Frame Size Sealant Water Flowrate
USGPM
Sealant Water Flowrate
m3/hr
LX Series Range 0.5 to 2.0
Nominal 1.0
Range 0.1 to 0.5
Nominal 0.3
Series 3 Range 1.5 to 3.0
Nominal 2.0
Range 0.3 to 0.7
Nominal 0.5
Series 4 Range 2.0 to 4.0
Nominal 3.0
Range 0.5 to 0.9
Nominal 0.7
Series 5 Range 5.0 to 11.0
Nominal 9.0
Range 1.1 to 2.5
Nominal 2.0
Series 6 Range 8.0 to 17.0
Nominal 12.0
Range 1.8 to 3.8
Nominal 2.7
Series 7 Range 25.0 to 40.0
Nominal 30.0
Range 5.7 to 9.0
Nominal 6.8
Series 8 Range 45.0 to 80.0
Nominal 60.0
Range 10.2 to 18.1
Nominal 13.6
Series 9 Range 50.0 to 70.0
Nominal 65.0
Range 11.3 to 15.9
Nominal 14.8
Series 10 Range 50.0 to 85.0
Nominal 75.0
Range 11.3 to 19.3
Nominal 17.0
Series 11 Range 70.0 to 110.0
Nominal 100.0
Range 15.9 to 25.0
Nominal 22.7
Series 12 Range 100.0 to 170.0
Nominal 150.0
Range 22.7 to 38.6
Nominal 34.0
Series 13 Range 150.0 to 230.0
Nominal 210.0
Range 34.0 to 52.2
Nominal 47.7
TABLE 1

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B) Flow Control
If a flow device is not used to measure the service liquid quantity to the pump, a regulating valve
and compound gauge in the service liquid line can be used to approximate the flowrate. For
pump operating pressures between atmospheric and 400 mmHgA, the reading on the compound
gauge should be in the range of 2" HgV to 5 psig (709 mmHgA to 0.35 barg). For operating
pressures below 400 mmHgA, the compound gauge reading should be in the range of 15" HgV
to 2 psig (379 mmHgA to 0.14 barg). This method is only an approximation of the service liquid
quantity. The actual operating conditions will dictate the amount of sealant liquid required and
also the compound gauge reading.
Another procedure used to establish minimum service liquid flow is to slowly reduce the flow
until the suction pressure fluctuates from the desired level. Gradually increase the flow until the
suction pressure stabilizes. This flow setting can be used as long as the temperature rise through
the pump remains reasonable (e.g., 10-20 ºF maximum for water sealant) and all other operating
conditions remain constant.
C) Hard Water
If hard water is used as the service liquid, scale deposits caused by the precipitation of mineral
salts will occur. This will vary with the temperature of the water. Scale deposits on the internal
surfaces of the pump will cause an increase of the operating horsepower, wear on moving parts,
and may cause the pump to seize.
If the hardness of the water is excessive, consider using a water softening treatment or a
descaling compound. If no alternatives are possible, it may be necessary to periodically
dismantle the pump to strip off the encrusted salts.
3.4 Cavitation
Cavitation is identified by a characteristic metallic or grinding noise inside the pump. It is
caused when the pump suction pressure is too close to the vapor pressure of the service liquid. If
the service liquid temperature inside the pump rises such that the vapor pressure closely
approaches the total suction pressure of the pump, cavitation will occur.

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When cavitation takes place, vapor bubbles form and collapse within the liquid ring. This will
damage the surfaces of the impeller, side plates, and casing. The cavitation shock force causes
damage by tearing away metal particles and deforming soft materials. The damage can be more
severe in a corrosive situation.
Cavitation is prevented by bleeding air into the pump to raise the suction pressure. Vacuum
relief valves can be fitted in the suction piping for this purpose.
If the problem is not caused by a low flow of non-condensable gases, the service liquid
temperature should be checked. With the proper temperature, the operating vacuum can be
increased. Ultimately, the vacuum at which the pump can be operated is governed by the vapor
pressure of the service liquid inside the pump.
3.5 Shut-Down Procedures
1) Shut off the service liquid supply, and if used, the shaft seal coolant, and immediately
stop the drive motor.
2) If necessary, close all suction and discharge valves.
3) If necessary, drain the pump to protect it from freezing by removing all drain plugs
by draining.
4) Disconnect power from the motor if maintenance is to be performed.
Section 4 - Accessory Items
4.1 Accessories
There are many accessory items associated with Liquid Ring Vacuum Pumps and Compressors.
They can be supplied by Graham and shipped from the factory or can be supplied by others and
installed in the field. The particular requirements, mode of operation, and type of control scheme
desired dictate the necessity of various items. The following is a list of common accessories.
Inlet Check Valve Used to prevent a back flow of gas into the process when the
pump is stopped. Check valves are normally installed in a
horizontal line. An elbow can be provided to adapt the vertical
pump inlet to accept a horizontal check valve.
Vacuum Relief Valve Used to protect the pump from cavitation and control the pump
suction pressure. When the pump capacity exceeds the system’s
flow requirements at a pre-determined level, the valve will open
and bleed in atmospheric air or process gas.

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Flexible Connector Used to compensate for minor misalignment or expansion
between the pump connections and the process piping.
Vacuum Gauge Used to indicate vacuum at the pump inlet. Normally mounted
directly ahead of the pump suction.
Shut-off Valve Used to manually stop the flow of service liquid to the pump.
Strainer Used to filter out solid particles that will damage the pump.
Flow Regulator Used to control the service liquid flow rate to the pump.
A manual valve, a fixed orifice, or a flexible element orifice may
be used depending on the application.
Compound Gauge Used to indicate pressure in the service liquid piping.
Discharge Separator Used to separate the service liquid from the discharged gas as it
comes out of the pump. The liquid can be piped to a drain or
recovered for re-use.
Solenoid Valve Used to automatically stop or start the flow of service liquid to
the pump. Normally interlocked to the pump motor.
By-pass Valve Used to initially fill the pump with service liquid or for bypass in
case the solenoid coil fails.
Recirculation Pump Used to circulate the service liquid recovered from the discharge
separator in some total recovery systems.
Heat Exchanger Used to remove heat from the recirculated service liquid.
Atmospheric Used to provide a suction pressure lower than the pump is
Air Ejector capable of when operating alone. It may be added to a two stage
pump to provide an inlet pressure as low as 3 mm HgA. The
operation of the air ejector is similar to that of a steam ejector.
Atmospheric air or recycled gas from the discharge separator is
used as the motive force for compressing the process gas from the
system design pressure up to the inlet pressure of the pump. To
enhance pumping capacity at a higher suction pressure, an
optional motive air shut-off valve or by-pass valve can be added.
(See Figure 2)

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FIGURE 2
Process Inlet
Optional
By-pass
Valve
Liquid Ring
Vacuum Pump
Discharge
Atmospheric
Air Ejector
Typical Atmospheric Air Ejector
Optional
Shut-off
Valve
Atmospheric
Air Inlet

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Section 5 - Maintenance
5.1 Performance
Optimum performance and long service life are dependent upon good maintenance procedures and
periodic inspections. When preparing to dismantle a pump, make provisions for the safe handling
of heavy parts.
5.2 Pump Estimated Weights
Refer to table in Appendix D for estimated pump weights.
5.3 Shaft Bearings
The standard bearings used in Graham model pumps are rated for a L10h life of 80,000 hours.
The temperature of the bearings should not exceed 140 oF (60 oC). Overheating may be due to
excess grease, misalignment of the shafts, or a bad bearing. Refer to Appendix C for bearing
information.
5.4 Gland Packings
Some large Graham pump models are available with gland packing. Refer to Appendix C for
gland packing information.
Adjustment: If the glands leak air into the pump or excessive leakage of service liquid occurs,
tighten the gland follower slightly. (See Section 3.2) If further tightening becomes impossible,
replace the packing.
5.5 Mechanical Seals
Graham pumps are fitted with single acting mechanical shaft seals manufactured to DIN24960
standard. They should be reconditioned or replaced when worn, scratched, cracked, or when the
rotating segment no longer grips the shaft. Seal elastomers should also be inspected and
replaced as appropriate. Refer to Appendix C for seal size information.
As an option, Graham model pumps are available with double mechanical seals as well as single
and double cartridge mechanical seals. The more elaborate seals of this style are utilized when
the pump is used in severe, corrosive or hazardous service. External seal flushing arrangements
are normally required for this type of service, as well as API Seal Flush plans and vessels using
barrier fluids. Contact the factory for specific information.

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5.6 Storage
If a pump is to be out of service, it should be protected internally from rusting by using a rust
inhibitor. The pump should be drained completely by removing all the lower plugs. Install the
plugs and fill with Oakite Ryconox 20M (or equal) preservative solution. Remove the
manifold(s) and spray the insides with preservative. Rotate the pump manually to circulate the
solution. Drain the pump to below the shaft centerline and replace the manifold(s). This
procedure may be disregarded for pumps made of stainless steel, bronze, Monel, or other
corrosion resistant materials.
Seal the flanged openings to prevent foreign material from entering the pump.
The pump shaft should be rotated each week to distribute the preservative and to prevent flat
spots on the bearings. Document the time, date, and by whom this procedure was performed.
The manifold(s) should be re-sprayed monthly and the pump checked to see that the preservative
is maintained. This will protect the pump for up to 12 months.
Pumps stored at low temperatures may need to be protected from freezing either by draining
completely or by using an anti-freeze solution.
Pumps with V-belt drives should have the belts loosened to relieve the belt tension during
storage. Do not store near running electric motors as ozone produced is detrimental to the rubber
in the belts.
5.7 Removal from storage
The pump should be drained and flushed if necessary to remove the preservative solution. Refer to
Section 3.1 of this manual for the recommended start-up procedure.
CAUTION:
THE OAKITE PRESERVATIVE SOLUTION IS PETROLEUM
BASED AND MUST BE DISPOSED OF IN ACCORDANCE WITH
ALL LOCAL, STATE, AND FEDERAL REGULATIONS.
A MSDS form can be found on the Graham web site at www.graham-mfg.com