Idex Wright Flow Technologies RTPe Series User manual

INSTALLATION,OPERATION
AND
MAINTENANCE MANUAL
FOR THE
RANGE OF PUMPS

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INSTALLATION, OPERATION AND MAINTENANCE MANUAL
FOR RTPeTM ROTARY LOBE PUMPS.
1.0 SAFETY INFORMATION. 3
1.1 RISK ASSESSMENT RELATING TO THE USE OF WRIGHT FLOW TECHNOLOGIES LIMITED RTPETM
ROTARY LOBE PUMPS. 6
2.0 INTRODUCTION. 7
2.1 GENERAL. 7
2.2 WRIGHT FLOW TECHNOLOGIES LIMITED DISTRIBUTORS. 7
2.3 RECEIPT AND STORAGE. 7
2.4 CLEANING. 8
2.5 PUMP MODEL DESIGNATION. 8
2.5.1 ATEX INFORMATION 9
3.0 GENERAL. 11
3.1 RTPETM PUMPING PRINCIPLE. 11
3.2 RTPETM OPERATING PARAMETERS. 12
3.3 SYSTEM DESIGN AND INSTALLATION. 12
3.3.2 CLEANING IN PLACE. 15
3.4 START-UP PROCEDURE. 16
3.5 SHUTDOWN PROCEDURE. 17
3.6 ROUTINE MAINTENANCE –NON ATEX UNITS. 17
3.6.1 ADDITIONAL ROUTINE MAINTENANCE –ATEX UNITS. 18
3.7 INTEGRAL PRESSURE RELIEF VALVE. 19
4.0 RTPETM PUMP DISASSEMBLY AND ASSEMBLY. 21
4.1 DISASSEMBLY. 22
4.1.1 FRONT COVER AND ROTOR REMOVAL 22
4.1.2 GEARBOX DISASSEMBLY 23
4.1.3 SHAFT DISASSEMBLY. 25
4.2 ASSEMBLY. 26
4.2.1 GEARBOX &ROTORCASE ASSEMBLY, 26
4.2.2 SHAFT ASSEMBLY –RTPE20 27
4.2.3 TIMING. 28
4.2.4 SETTING THE ROLLING TORQUE. 30
4.2.5 ROTOR CLEARANCES. 30
4.3 PRODUCT SEAL FITTING AND REMOVAL. 31
4.3.1 GENERAL PROCEDURES FOR INSTALLING SEALS. 31
4.3.2 RTPE20 COMPOSITE O-RING SEAL REMOVAL AND INSTALLATION. 32
4.3.3 RTPE20 MECHANICAL SEAL. 34

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5.0 SPECIFICATIONS. 35
5.1 CLEARANCE CHART 35
5.2 FASTENERS &TORQUE SETTINGS. 36
5.3 LUBRICANTS. 37
5.4 TOOL LIST. 37
5.5.1 RTPE20 FOUNDATION DIMENSIONS –BASIC PUMP METRIC (1” FEMALE DRIVE) 38
5.5.2 RTPE20 FOUNDATION DIMENSIONS –BASIC PUMP INCH (1” FEMALE DRIVE) 39
5.6 TYPICAL BASIC PUMP BUILD (RTPE20 SHOWN) 40
5.7 TROUBLE SHOOTING. 41
5.8 RTPETM SERVICE HISTORY. 43
5.9 NOTES. 44

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1.0 Safety Information.
INCORRECT INSTALLATION, OPERATION, OR MAINTENANCE OF
EQUIPMENT MAY CAUSE SEVERE PERSONAL INJURY OR DEATH
AND/OR EQUIPMENT DAMAGE THAT MAY INVALIDATE THE
WARRANTY.
THIS INFORMATION MUST BE READ FULLY BEFORE BEGINNING
INSTALLATION, OPERATION, OR MAINTENANCE AND MUST BE KEPT
WITH THE PUMP. ONLY SUITABLY TRAINED OR QUALIFIED PERSONS
SHOULD UNDERTAKE INSTALLATION AND MAINTENANCE.
DANGER
DO NOT OPERATE PUMP IF:
- The front cover is not installed correctly.
- Any guards are missing or incorrectly installed.
- The suction or discharge piping is not connected.
DO NOT place fingers, etc. into the pumping chamber or its connection ports
or into any part of the gearbox if there is ANY possibility of the pump shafts
being rotated. A severe injury will occur.
DO NOT exceed the pumps rated pressure, speed, and temperature, or
change the system/duty parameters from those for which the pump was
originally supplied, without confirming its suitability for the new duty. Running
the pump outside of its operations envelope can cause mechanical contact,
excessive heat and can represent a serious risk to health and safety.
Installation and operation of the pump must always comply with health and
safety regulations.
A device must be incorporated into the pump, system, or drive to prevent the
pump from exceeding its stated duty pressure. It must be suitable for both
directions of pump rotation where applicable. Do not allow the pump to
operate with a closed/blocked discharge unless a pressure relief device is
incorporated. If an integral relief valve is incorporated into the pump, do not
allow re-circulation through the relief valve for extended periods; (refer to
section 3.7).
Danger - Failure to follow the listed
precautionary measures may result in
serious injury or death. Areas of
potential risk are identified by the
following symbol:
Warning - Safety instructions which shall
be considered for reasons of safe
operation of the pump or pump unit and/or
protection of the pump or pump unit itself
are marked by the sign:
WARNING
WARNING

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The mounting of the pump or pump unit should be solid and stable. Pump
orientation must be considered in relation to drainage requirements. Once
mounted, shaft drive elements must be checked for correct alignment. Rotate
pump shaft by at least one full revolution to ensure smoothness of operation.
Incorrect alignment will produce excessive loading, create high temperatures
and increased noise emissions. Do not use any drive arrangements, which
cause side loading of the drive shaft. It may also be necessary to earth the
pump head to avoid the build-up of a potential charge that could cause a
spark.
The installation must allow safe routine maintenance and inspection (to
replenish lubricants, check for leakage, monitor pressures, etc.) and provide
adequate ventilation necessary to prevent overheating.
Fill all gearboxes with the recommended grades and quantities of lubricant;
(refer to section 5.3). Beware of over/under filling the gearbox as this could
cause the pump to overheat and severe mechanical damage to occur.
Before operating the pump, be sure that it and all parts of the system to which
it is connected are clean and free from debris and that all valves in the suction
and discharge pipelines are fully opened. Ensure that all piping connecting to
the pump is fully supported and correctly aligned with its relevant connections.
Misalignment and/or excess loads will cause severe pump damage. This
could result in unexpected mechanical contact in the pump head and has the
potential to be a source of ignition.
Be sure that pump rotation is correct for the desired direction of flow; (refer to
section 3.1).
Do not install the pump into a system where prolonged run dry will occur (i.e.
without a supply of pumped media). Mechanical seals require a thin fluid film
to lubricate the seal faces. Dry running will cause excessive heat and seal
failure. Composite O-ring are dry run capable for a limited time.
Pressure gauges/sensors are recommended, next to the pump suction and
discharge connections to monitor pressures.
Caution must be taken when lifting the pump. Suitable lifting devices should
be used as appropriate. Lifting eyes installed on the pump must only be used
to lift the pump, not pump with drive and/or baseplate. If the pump is
baseplate mounted, the base plate must be used for all lifting purposes. If
slings are used for lifting, they must be safely and securely attached. For
weights of the bare shaft, pumps refer to section 5.5.1 & 5.5.2
WARNING
WARNING
WARNING
WARNING
WARNING

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DO NOT attempt any maintenance or disassembly of the pump or pump unit
without first ensuring that:
-The pump is fully isolated from the power source (electric, hydraulic,
pneumatic).
- The pumping chamber, pneumatic relief valve and any shaft seal
support system are depressurised and purged.
- Any temperature control devices (jackets, heat-tracing, etc.) are fully
isolated, that they are depressurised and purged, and components are
allowed to reach a safe handling temperature.
Use only genuine Wright Flow Technologies parts.
All certification, standards, guarantees & warranties originally supplied with
this pump will be invalidated by the use of non-genuine Service Parts.
DO NOT attempt to dismantle a pressure relief valve which has not had the
spring pressure relieved, is still connected to a pressurised gas/air supply or is
mounted on a pump that is operating. Serious personal injury or death and/or
pump damage may occur.
Use only genuine Wright Flow Technologies parts.
All certification, standards, guarantees & warranties originally supplied
with this pump will be invalidated by the use of non-genuine Service
Parts.
DO NOT loosen or undo the front cover, any connections to the pump, shaft
seal housings, temperature control devices, or other components, until sure
that such action will not allow the unsafe escape of any pressurised media.
Pumps and/or drives can produce sound power levels exceeding 85-dB (A)
under certain operating conditions. When necessary, personal protection
against noise must be taken.
Avoid any contact with hot parts of pumps and/or drives, which may cause
injury. Certain operating conditions, temperature control devices (jackets,
heat-tracing, etc.), bad installation, or poor maintenance can all promote high
temperatures on pumps and/or drives.
When cleaning, either manually or by CIP method, the operator must ensure
that a suitable procedure is used in accordance with the system requirements.
During a CIP cleaning cycle, a pump differential pressure of between 2 and 3
bar (30 to 45 psi) is recommended to ensure suitable velocities are reached
within the pump head. The exterior of the pump should be cleaned
periodically.
The surface temperature of the pump is also dependent on the temperature of
the pumped medium.
WARNING
WARNING

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1.1 Risk assessment relating to the use of Wright Flow Technologies Limited
RTPeTM rotary lobe pumps.
Note:- For a feature to be suitable for an application, The feature must be fit for its
designated purpose and also suitable for the environment where it is to be installed.

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2.0 Introduction.
2.1 General.
RTPeTM rotary lobe pump is manufactured by Wright Flow Technologies
Limited a unit of the IDEX Corporation.
This manual includes all the necessary information for RTPeTM pumps and
should be read prior to beginning installation, operation and maintenance.
Should you require any additional information regarding the RTPeTM pumps
contact Wright Flow Technologies Limited or their local authorised distributor
(refer to section 2.2).
When asking for assistance, please provide the pump model and serial
number. This information can be obtained from the pump nameplate, which is
located on the side of the pump gearbox, see fig 2. Should the nameplate be
unreadable or missing, the pump serial number is also stamped on either side
of the rotorcase, see fig 3.
If the system or product characteristics are to be changed from the original
application for which the pump was selected, Wright Flow Technologies
Limited or their authorised distributor should be consulted to ensure the pump
is suitable for the new application.
2.2 Wright Flow Technologies Limited Distributors.
Wright Flow Technologies Limited distributes its products internationally via a
network of authorised distributors. Throughout this manual where reference is
made to Wright Flow Technologies Limited, service and assistance will also be
provided by any Wright Flow Technologies Limited authorised distributor for
RTPeTM pumps.
2.3 Receipt and Storage.
Upon receipt of the pump, immediately examine it for any signs of visible
damage. If any damage is noted, contact Wright Flow Technologies Limited or
your Wright Flow Technologies Limited distributor and clearly mark upon the
carriers paperwork that the goods have been received in a damaged condition,
with a brief description of the damage.
If the pump is not required for immediate installation then it should be stored
in a clean, dry environment. It is recommended that storage temperature
should be between –10°C and 40°C (14°F and 105°F).

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2.4 Cleaning.
The RTPeTM pump series is suitable for both manual cleaning and CIP
(Cleaning In Place), refer to section 3.3.2.
The strategic positioning of the product seals, combined with their ease of
access provides an arrangement that can be more effectively cleaned by both
manual and CIP procedures.
It is recommended that the exterior of the pump be cleaned periodically.
2.5 Pump Model Designation.
Fig 1 Designation of pump models
This information, together with the pump serial number, should be provided
when requesting additional information on the pump or when ordering spare
parts. The pump serial number is stamped on the pump nameplate(Fig 2) and
the rotorcase, (Fig 3). For the maximum operating pressures, temperatures
and speeds refer to section 3.2.
RTPe
TM
20
0100
10
/
/
PUMP
MODEL
DISPLACEMENT
(1 LTRS/REV.)
MODEL
SIZE
MAX.PRESSURE
(BAR)

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Page 9
2.5.1 ATEX Information
ATEX Pump Requirements
Mechanical seals are a source of heat and must never be allowed to run dry.
We would recommend provision be made to ensure that there is always flow
or fluid around the pump seals. If there is a risk of the supply being
interrupted, then a temperature monitoring system must be applied to ensure
the pump does not exceed the Atex rating. The surface temperature of the
pump is dependent on the temperature of the pumped fluid and a due account
of this should be taken whilst undertaking your risk assessment of the
installation. These pumps are Atex rated T3.
Only use genuine spare parts that have been designed and verified Atex
compliant by Wright Flow Technologies, failure to use genuine spare parts will
invalidate the Atex certification.
Pumps that have the Atex certification will have an earthing point on the front
cover, this needs to be electrically earthed before use.
The service and maintenance intervals are increased on certified Atex units,
refer to section 3.6.1 for the required routine maintenance. Failure to maintain
the pumps to these intervals will result in the Atex certification being
invalidated.
When installing the unit make sure so far as reasonably practicable that the
pump is aligned within 5 degrees to the horizontal –failure to align the unit
could adversely affect the gearbox lubrication and could cause heat to build
up.
It is the end user’s responsibility to ensure that the Atex rating of the
equipment supplied meets the requirements of the installation.
2.5.2 Equipment Groups & Categories
The RTP pump range has been rated as
WARNING
WARNING
WARNING
WARNING
Category 2
Temperature Class T3
Unit is suitable for environments
containing dust or gas G/D
Group II.

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Fig 3 Serial Number Location.
Fig 2 Nameplate.
The Atex rating is displayed on the pump nameplate see fig 2
2.6 Pump Model and Serial Number.
Should you require any information regarding your RTPeTM rotary lobe pump
contact Wright Flow Technologies Limited or your Wright Flow Technologies
Limited distributor, providing the pump model and serial number as stated on
the pump nameplate, see Fig 2, which is fixed to the pump gearbox. Should
this be damaged or missing, the pump serial number is also stamped on face
of the flange of the rotorcase, (see Fig 3).
EG 123456/A/12

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3.0 General.
3.1 RTPeTM Pumping Principle.
The pumping action of the rotary lobe pump principle is generated by the
contra-rotation of two pumping elements (rotors) within a chamber (rotorcase),
Fig 4. The shaft assemblies comprise of, the shaft support bearings and the
timing gears. The gears transfer the energy from the drive shaft to the driven
shaft, synchronising the rotors such that they rotate without contact with each
other.
As the rotors pass the suction port, (‘A’), the cavity increases creating a
pressure decrease, which induces the pumped medium to flow into the
rotorcase.
The pumped medium is carried around the rotorcase by the rotors, (‘B’) and
(‘C’), to the discharge side of the pump, (‘D’). Here the cavity decreases, and
the pumped medium is discharged from the rotorcase, (‘E’).
Fig 4 Rotary Lobe Pump Principle.

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3.2 RTPeTM Operating Parameters.
Fig 5 Operating Parameters
RTPe20
Theoretical Displacement
Nominal Connection
Size
Max-Diff.
Pressure
Maximum
Speed
Max
Temp
Max
Temp
Litre/ rev
Imp.gal
/100 rev
US gal /
100 rev
mm
inches
bar
psi
rev/min
C
F
1.00
21.9
26.4
75
3
10
145
1000
110
230
The maximum pressure and speed operating parameters are given above. In
practice, there may be limits due to the nature of the product to be pumped
and/or design of the system in which the pump is to be installed. Consult
Wright Flow Technologies Limited or your Wright Flow Technologies Limited
distributor for assistance.
If the system or product characteristics are to be changed from the original
application for which the pump was selected, Wright Flow Technologies
Limited or their authorised distributor should be consulted to ensure the pump
is suitable for the new application.
The pump should not be subjected to sudden temperature changes to avoid
the risk of damage from sudden expansion/contraction of components. Care
should be taken when selecting pumps for handling liquids containing abrasive
particles as these may cause wear of pump head components. For advice or
assistance contact Wright Flow Technologies Limited or your Wright Flow
Technologies Limited distributor.
3.3 System Design and Installation.
When incorporating any pump into a system it is considered a good practice
to minimize piping runs and the number of pipe fittings (tees, unions, bends
etc.) and restrictions. Particular care should be taken in designing the suction
line, which should be as short and straight as possible with a minimum of pipe
fittings to minimise restricting product flow to the pump. The following should
be considered at the design stage of any system
Be sure ample room is provided around the pump to allow for:
•Access to the pump and drive for routine inspection and maintenance, i.e.
to remove pump front cover and rotors.
WARNING

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•Ventilation of the drive to prevent overheating.
The exterior of the pump unit may exceed 68C (154F),
Appropriate measures must be taken to warn or protect operators.
The pump must not be used to support piping. All piping to and from the pump
unit must be independently supported. Failure to observe this may distort the
pump head components or assembly and cause serious consequential
damage to the pump.
Valves should be provided adjacent to the pump suction and discharge
connections to allow the pump to be isolated from the system for routine
inspection and maintenance.
Rotary lobe pumps are of the positive displacement type and therefore an
overload protection device must be provided. This can take the form of:
•An pressure relief system, i.e. integrated to the pump.
•An in-line pressure relief system, i.e. external to the pump.
•Incorporation of a torque-limiting device in the drive system.
It is recommended that all piping and associated equipment from the tank to
the discharge point is thoroughly cleaned before installation of the pump to
avoid the possibility of debris entering the pump and causing damage.
Pressure gauges should be installed adjacent to the pump suction and
discharge connections such that system pressures can be monitored. These
gauges will provide a clear indication of changes in operating conditions and
where a relief valve is incorporated in the system, will be necessary for setting
and checking the functioning of the valve.
It is imperative that the suction condition at the pump inlet meets the Net
Positive Suction Head required (NPSHr) by the pump. Failure to observe this
could cause cavitation, resulting in noisy operation, reduction in flow rate and
mechanical damage to the pump and associated equipment.
The Net Positive Suction Head available (NPSHa) from the system must
always exceed the Net Positive Suction Head required (NPSHr) by the pump
WARNING
WARNING
WARNING
WARNING
WARNING

Page | 14
Observing the following general guidelines should ensure the best possible
suction condition is created.
•Suction piping is at least the same diameter as the pump connections.
•The length of suction piping is kept to the absolute minimum.
•The minimum number of bends, tees and pipework restrictions are used.
•Calculations to determine system NPSHa are carried out for the worst
condition see below.
Should advise on pump or system NPSH characteristics be required then
contact the factory or their authorised distributor.
Fig 6
10.0 Meters (32.8 Feet) Water Column
Suction Lift
Or Vacuum
Atmospheric
Pressure
Suction
Head
NPSH
Available
Suction Line
Friction Loss
Vapour
Pressure
NPSH
Available
Suction Line
Friction Loss
Vapour
Pressure
For Suction Lift
Or Vacuum
Conditions.
For Conditions
With Positive
Suction Head.
Atmospheric
Vacuum

Page | 15
Where motor mounting options are to be installed follow the manufactures
recommended guidelines. However, when installing a pump complete with base and
drive the following guidelines must be observed:
•The preferred drive arrangement for the RTPeTM pump is close coupled.
•If flexible couplings are used they must be incorporated and correctly aligned within
the limits recommended by the coupling manufacturer. To check coupling alignment
rotate the shaft by at least one full revolution and ensure that the shaft rotates
smoothly.
Couplings of a non-flexible design must never be used.
•Couplings must always be enclosed in a suitable guard to prevent contact with
rotating parts that could result in personal injury. Guards should be of suitable
material, and of sufficiently rigid design to prevent contact with rotating parts
under normal operating conditions.
•When installing pump sets in flammable or explosive environments, or for
handling flammable or explosive materials, special consideration must be given
not only to the safety aspects of the drive unit enclosure but also to the materials
used for both the coupling and the guard to eliminate the risk of explosion.
•Baseplates must be secured to a flat level surface such that distortion and
misalignment are avoided. Once baseplates are fastened in position the drive
alignment must be re-checked.
•When using electric motor drives, ensure that the electrical supply is compatible
with the drive and controls and that the method of wiring is correct for the type of
starting required by the motor i.e. Direct On-Line, or another similar method.
Ensure all components are correctly grounded.
3.3.2 Cleaning In Place.
The RTPeTM can be effectively cleaned. To assist in maximising the effectiveness of
cleaning within the pump head it is recommended that the cleaning cycle has a flow rate
equivalent to a velocity of 1.5 metres per second; in a pipe of equal diameter to the rotor
case connections. With a differential pressure of 2 to 3 bar (30 to 45 psi) being
developed across the pump head.
For applications where, maximum drainage of the pump head is required, for example in
the handling of ‘Agri-Foodstuffs’ and/or where CIP is employed, the pump ideally should
be mounted with the rotor case connections in the vertical orientation. A procedure must
be determined to ensure that the pump is effectively cleaned. Any cleaning liquids must
be appropriate to both the products being handled and the materials of construction of
the pump.

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3.4 Start-Up Procedure.
- Check that all piping and associated equipment are clean and free from
debris and that all pipe connections are secure and leak free.
- Refer to section 5.3 for lubricant capacities and grades.
As standard, the pump is shipped with grease lubricant unless otherwise
specified. The oil filled pumps differ in gearbox construction where
breather, drain plug, and sight glasses are fitted.
- If an external relief valve is incorporated in the system check that it is set
correctly. For start-up purposes, it is considered a good practice to set the
relief valve lower than the system design pressure. On completion of start
up the relief valve should be reset to the required setting for the
application. The required setting should never exceed the lower of either
the pumps maximum pressure rating or the system design pressure.
- Ensure both suction and discharge valves are fully open, and pipework is
free from all obstructions. RTPeTM pumps are of the positive displacement
type and should therefore never be operated against a closed valve as this
would result in pressure overload, resulting in damage to the pump and
possibly the system.
- Ensure rotation of the drive shaft is correct for the direction of flow
required, see Fig 7.
Fig 7 Direction of Rotation
WARNING
WARNING
WARNING
WARNING
WARNING

Page | 17
- Ensure product is available at the inlet before starting the pump. The
Composite seal are dry run capable for a limited time, the risk of seal
failure increases with mechanical seal if allowed to run dry.
- Before beginning operation, it is considered a good practice to
momentarily start/stop the pump to check the direction of rotation and
ensure that the pump is free of obstructions. Once this has been carried
out, begin operation keeping a visual check on suction and discharge
pressure gauges and monitor pump temperature and power absorbed
where possible.
3.5 Shutdown Procedure.
When shutting the pump down, stop the pump, close both the suction and
discharge valves and ensure that the necessary safety precautions are taken:
- The prime mover power source has been isolated.
-Pump head and piping have been drained and purged.
3.6 Routine Maintenance –Non Atex units.
Grease
-Check for any signs of lubricant leakage
-Low maintenance gearbox, factory filled with EP 00 semi-fluid grease.
The grease should not require replacement during the lifetime of the
bearings or until 20,000 hours of operation.
Oil
-Check oil levels regularly.
-Change the oil every 12 months or 3000 operating hours, whichever is
the sooner.
For lubricant capacities and grades refer to section 5.3.
Seal Replacement Interval:
It is recommended that the Rotor Retainer O-ring seal is replaced every 12
months to maintain a bacteria-tight seal.
Rotor Retainer Seal Inspection:
Periodically inspect the Rotor Retainer O-ring seal for any discolouration,
nicks, or cracks. If any of the defects above are noticed, the O-ring seal must
be replaced. Inspection and replacement refer to the seal replacement
procedure.
WARNING
WARNING

Page | 18
3.6.1 Additional Routine Maintenance –Atex units.
Grease
-Check for any signs of lubricant leakage on startup.
-Check for any signs of overheating.
Low maintenance gearbox, factory filled with EP 00 semi-fluid grease. The
grease should not require replacement during the lifetime of the bearings or
until 14,000 hours of operation.
Oil
-Check oil levels on startup.
-Check for any signs of overheating.
-Change the oil every 6 months or 1500 operating hours, whichever is
the sooner.
For lubricant capacities and grades refer to section 5.3.
After 14000 hours of use, the pump will need a general overhaul and it will
need to be re-certified for use within the Atex environment.
A general overhaul must include a full disassembly of all components and the
following work carried out.
•Clean all pump components
•Examination of all components for damage/wear
•Replacement of all taper roller bearings
•Replacement of all elastomeric components
•Replacement of all seals, radial seals, and Gamma rings
The general overhaul must be carried out by qualified personnel in a specialist
workshop with the appropriate equipment. Re-certification must then be
carried out.
We highly recommend that the general overhaul is carried out by Wright Flow
Technologies
WARNING
WARNING

Page | 19
3.7 Integral Pressure Relief Valve.
Integral pressure relief valves are normally used to protect the pump from the
effects of increases in system pressure caused, for example, by a restricted or
closed discharge line. In response to a pressure increase, the valve opens and
internally circulates the pumped media within the pump chamber.
When the valve opens, because the volume of fluid circulating is relatively
small, the temperature of the fluid in the pump chamber may rise if the pump
continues to operate for an extended period. In severe cases, this may result
in temperatures in excess of the pumps operating limits or vaporisation of the
fluid. For these reasons when the valve has activated the cause of the system
pressure increase should be eliminated as continuous operation of the pump
with the valve open is not recommended and may cause severe damage to
the pump.
If the pump on which the valve is installed is to be installed in either a
pressurised system or one incorporating a vessel under vacuum, the
application of the valve should be referred to Wright Flow Technologies
Limited or their authorised distributor. In addition to where the pump is
mounted onto a mobile unit with drive, it is recommended that an integral
pressure relief valve is installed.
Note: Care should be taken not to exceed either the pumps maximum
pressure rating or the system design pressure.
The spring housing component including spring and valve; are manufactured
as complete units and available in 6.5 and 8 bar options. This must be
specified at the time of order. If further adjustment is required to the
assemblies consult Wright Flow Technologies Limited or your local Wright
Flow Technologies Limited distributor.
WARNING
WARNING