Corken PT Series Instruction manual

Installation, Operation
& Maintenance Manual
PT-Series Petroleum Pumps
For Refined Petroleum Products and Industrial Solvents
ORIGINAL INSTRUCTIONS ID108H
Warning: (1) Periodic inspection and maintenance of Corken products is essential. (2) Inspection, maintenance and installation of Corken
products must be made only by experienced, trained and qualified personnel. (3) Maintenance, use and installation of Corken products
must comply with Corken instructions, applicable laws and safety standards (such as NFPA Pamphlet 58 for LP-Gas and ANSI K61.1-1972
for Anhydrous Ammonia). (4) Transfer of toxic, dangerous, flammable or explosive substances using Corken products is at user’s risk and
equipment should be operated only by qualified personnel according to applicable laws and safety standards.
Model PT30
Model PT20
Model PT25 with optional air operated
valve (AOV) and strainer
Solutions beyond products...
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Warning
Install, use, and maintain this equipment according to Corken’s instructions and all applicable federal, state, local
laws, and codes. Periodic inspection and maintenance is essential.
Corken One Year Limited Warranty
Corken warrants that its products will be free from defects in material and workmanship for a period of one year
from date of installation, provided that the warranty shall not extend beyond twenty-four (24) months from the date
of shipment from Corken. If a warranty dispute occurs, the distributor may be required to provide Corken with proof
of date of sale. The minimum requirement would be a copy of the distributor’s invoice to the customer. Corken
products which fail within the warranty period due to defects in material or workmanship will be repaired or replaced
at Corken’s option, when returned, freight prepaid to Corken, Inc., 9201 North I-35 Service Road, Oklahoma City,
OK. 73131.
Parts subject to wear or abuse, such as mechanical seals, vanes, piston rings, packing and other parts showing
signs of abuse are not covered by this limited warranty. Also, equipment, parts and accessories not manufactured
by Corken but furnished with Corken products are not covered by this limited warranty and purchaser must look to
the original manufacturer’s warranty, if any. This limited warranty is void if the Corken product has been altered or
repaired without the consent of Corken.
All implied warranties, including any implied warranty of merchantability or fitness for a particular purpose, are
expressly negated to the extent permitted by law and shall in no event extend beyond the expressed warranty period.
Corken disclaims any liability for consequential damages due to breach of any written or implied warranty on Corken
products. Transfer of toxic, dangerous, flammable or explosive substances using Corken products is at the user’s
risk. Such substances should be handled by experienced, trained personnel in compliance with governmental and
industrial safety standards.
Important notes relating to the European Union (EU) Machinery Directive
Pumps delivered without electric motors are not considered as machines in the EU Machinery Directive. These
pumps will be delivered with a Declaration of Incorporation. The fabricator of the machinery must assure and declare
full compliance with this Directive before the machine in which the pump will be incorporated, or of which it is a part,
is put into service.
Contacting the Factory
Before contacting the factory, note the model and serial numbers. The serial number directs Corken personnel to a
file containing all information on material specifications and test data applying to the product. When ordering parts,
the Corken service manual or Installation, Operations, and Maintenance (IOM) manual should be consulted for the
proper part numbers. ALWAYS INCLUDE THE MODEL NUMBER AND SERIAL NUMBER WHEN ORDERING PARTS.
The model and serial numbers are shown on the nameplate of the unit. Record this information for future reference.
Model No.
Serial No.
Date Purchased
Date Installed
Purchased From
Installed By
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Table of Contents
Principles of the PT-Series Pumps...............................................................4
Exclusive Features of the PT-Series Pumps .......................................................4
Chapter 1—Installation (Truck) ..................................................................5
1.1 Power Take-Off Drive Systems ...............................................................5
1.2 Hydraulic Drive Installation ..................................................................6
1.3 Pump Rotation ............................................................................6
Chapter 2–Operation (Truck)....................................................................6
Chapter 3–Installation (Stationary) ..............................................................7
3.1 Coupling alignment ........................................................................7
3.2 Driver Installation ..........................................................................8
Chapter 4–Operation (Stationary) ...............................................................9
Chapter 5—Maintenance of the Pump System .....................................................9
5.1 Pump Maintenance Schedule ...............................................................10
5.2 Bearing Lubrication .......................................................................10
5.4 Strainers................................................................................10
5.5 Disassembly Instructions...................................................................10
5.6 Assembly Instructions .....................................................................11
5.7 Vane Replacement ........................................................................12
5.8 Bypass Valve Assembly....................................................................13
5.9 Air Operated Valve (AOV) Assembly ..........................................................13
Chapter 6–Repair Kits ........................................................................14
Appendices
A. Model Number Identification Code and Available Options..........................................15
B. Specifications ............................................................................16
C. Performance .............................................................................17
D. Outline Dimensions ........................................................................19
E. Parts Details .............................................................................26
F. Troubleshooting Guide......................................................................36
G. Extended Storage .........................................................................37
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Principles of the PT-Series Pumps
The PT-Series pumps are a special type of rotary positive
displacement pump, known as a sliding vane pump.
The sliding vane pump has many of the positive displacement
advantages of the gear pump, plus the ability to compensate
for wear, and operate at a lower noise level.
The sliding vane pump consists of a rotor turning inside a
cam that is machined eccentrically in relation to the rotor.
As the rotor turns, the liquid that is trapped between the
rotor, cam and vanes is displaced. The PT-Series pumps
are made with vanes produced from advanced polymers
which exhibit extremely low coefficients of friction. The
self adjusting vanes compensate for wear and help extend
the life of the pump.
Exclusive Features of the
PT-Series Pumps
Pumping liquids from a delivery truck can be difficult,so more
attention must be given to the design and manufacturing of
the pump and to its installation and operation.
In addition to being well suited for handling petroleum
products, PT-Series pumps have a number of other
features that make it easy to operate and maintain.
Heavy duty ball
bearings provide
greater durability
and strength.
Available with
standard bypass
valve or optional
air operated
valve (AOV) for
high and low
flow control.
Conveniently located
drain plug allows for
quick emptying of the
pump when necessary.
Self adjusting
vanes compensate
for wear.
O-ring design delivers
maximum sealing
capability and is
available with optional
seal materials.
Corrosion resistant
bypass valve.
Reliable mechanical
seal design with
optional seal materials.
Hollow rotor helps
reduce weight.
Optional flanges and
strainer available.
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Chapter 1—Installation (Truck)
The mechanical installation of the PT-Series pump is a
simple matter. A rotation arrow is located on the side of
the pump. Examine the PTO and determine the direction
of its rotation before installing the pump. The PT-Series
pump will match either PTO rotation. Connect the drive
shaft to the pump shaft that turns the pump in the
direction of the arrow.
The PTO SELECTION is important. For maximum
performance, the pump requires a PTO with an average
output speed of 500 to 700 RPM. In addition, the truck
engine must be operating at the appropriate RPM
to maintain oil pressure, water circulation, and the
electrical system.
THE DRIVESHAFT that connects the pump to the PTO
should be of the “splined” or slip type. This type of
driveshaft permits the shaft to adjust for PTO movement
and twisting of the truck frame. A fixed driveshaft will
transfer the forces directly to the pump and PTO and
shorten the life of both considerably. The yokes of the
driveshaft universal joints must be positioned as shown
in Figure 1. Improper positioning will cause premature
wear and potentially destroy the bearings in the pump
and PTO.
INLET PIPING should be as short as possible and at least
the minimum diameter specified for the model with few
restrictions so that the pressure drop is limited.
The outlet piping should include the following:
1. A pressure gauge should be installed in the pump
outlet or near it. A pressure gauge is necessary to
determine the efficiency of the pumping system.
2. If a meter with an air eliminator is installed, never pipe
the eliminator directly into the pump inlet piping or
into the liquid part of the system at any point (refer to
the meter installation manual).
3. The discharge piping should be at least the same size
as the meter piping.
1.1 Power Take-Off Drive Systems
Proper pump operation and long life is directly dependent
upon a good drive system. Many truck pumps utilize
a power train consisting of shafts and universal joints
located between the power take-off shaft of the truck
engine and the pump.
There are several basic principles that should be followed
in designing a PTO drive. To produce a workable power
train that results in long pump life and reduced drive
wear, these principles should not be violated.
First, the driver shaft and the driven shaft must be parallel
to one another within plus or minus one degree. Improper
alignment will cause jerking and back and forth “whip”
to the pump shaft; thereby imparting a surging pulsation
to the liquid flow which results in noise, vibration and
abnormal wear.
Second, the angle of the “floating” shaft should be within
the limits for the particular equipment being used (usually
a maximum of 15° at pump speeds up to 800 RPM). To
ensure that shaft expansion or contraction does not
distort the drive system, a splined slip joint should be
placed between the two universal joints. Again, the drive
shaft should be of the “splined” or slip type to permit
the shaft to adjust for PTO movement and twisting of
the truck frame. A fixed drive shaft transmits the forces
directly to the pump and PTO which will shorten the life
of both considerably.
Third, the yokes of the drive shaft universal joints must be
in a parallel position. Figure 1 below illustrates the proper
arrangement of the yokes.
Improperly installed U-joints will cause premature failure
of U-joints as well as bearings in the pump and PTO.
Properly mounted, the second universal gives uniform
motion to the drive shaft by compensating for the
rotational error introduced by the first U-joint. An even
number of universal joints (2, 4, 6 etc.) should always be
used. An odd number of U-joints will cause unbalanced
pump shaft rotation. This problem becomes greater with
increased angularity.
Other points to consider include the proper sizing of the
shaft components with a maximum horsepower load to
be expected, good alignment of hanger bearings and
proper pump coupling alignment.
Improper PTO systems account for a high percentage
of truck pump failures. Always remember to disengage
the clutch before shifting the PTO into gear. Shifting the
PTO into gear without disengaging the clutch imparts
an enormous shock on the PTO, drive shaft, pump and
meter and will soon damage one or all of them.
For proper installation of pump drives, follow the rules
listed below:
1. Driver shaft and pump shaft must be parallel, plus or
minus one degree.
2. Operating angle of the “floating” shaft must be 15°
maximum.
3. Universal yokes must be in line and parallel.
4. Splined slip joints must be used where needed.
5. Use an even number of universal joints.
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Figure 1: Shaft alignment
Note: A drive shaft guard between the pump and
PTO should be installed (not shown).
6. Always use the least practical number of shafts.
PTO selection and drive system design is extremely
important. The PTO should have an average output
speed up to 640 RPM to maximize the performance of
the PT-Series pump when the truck engine is operating
at the recommended speed.
The designer of the drive system must select a PTO drive
shaft capable of meeting the torque requirements of the
pumping system.
1.2 Hydraulic Drive Installation
Hydraulic motors must be well supported and keep
their shafts parallel to the pump shaft. To drive the
PT-Series pumps hydraulically, Corken provides a close-
coupled hydraulic motor adapter. The adapter aligns the
hydraulic motor drive and the pump shaft via a lockring
and a flexible coupling connected to a keyed shaft. This
adapter must be lubricated with grease at least every
three months. Refer to the “Bearing Lubrication” section
of this manual for instructions.
Figure 2: Hydraulic Drive (see Appendix E for Part Details)
1.3 Pump Rotation
For proper pump rotation, make sure the pump’s rotation
arrows match the pump driver rotation (see Appendix E
for parts details).
Direction of Rotation
Left hand/counter clockwise rotation
(PS25L)
Right hand/clockwise rotation
(PS25R)
Figure 3: Direction of Rotation
Chapter 2–Operation (Truck)
The following steps should be performed for the initial
pumping operation:
1. Close the shutoff valve on the end of the delivery
hose.
2. Start the pump and cycle the nozzle open and closed
to clear all air from the system.
3. Check the discharge pressure on the outlet of the
pump. This pressure is typically set at 80 to 95 psi.
4. Bypass Valve Adjustment
For a standard bypass valve, locate the adjustment
set screw under the bypass valve cap (see Appendix E
for parts details). Turn adjustment screw clockwise to
increase pressure and flow. Turn counter clockwise to
decrease pressure and flow.
Close the nozzle and check the bypass pressure. If
too high, turn adjustment screw counter clockwise
until desired pressure is reached.
With the hose nozzle open, adjust the pump bypass
valve setting to the desired flow rate. Close the nozzle
slowly and check the system pressure. CAUTION: DO
NOT EXCEED A CLOSED NOZZLE PRESSURE OF
125 PSI.
Replace bypass valve cap and bypass valve cap
gasket with seal washer and tighten.
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5. Air Operated Valve (AOV) Adjustment
Truck Tank
Flow Sensing Valve
Check Valve
Shut Off Valve
Air Cylinder Engine
Speed Control
Hose Reel
Use either a direct “Push” throttle
rod or connected “Pull” with cable
Carburetor
Injector
Pump
or
Air Filter
Truck Air
Supply
Pump with Air
Operated Valve (AOV)
Figure 4: Typical truck delivery system using an AOV.
For pumps equipped with an Air Operated Valve
(AOV) assembly, air must be supplied from the truck
air system via a flow sensing valve. Approximately
70 psi (4.8 bar) minimum air pressure is required to
properly operate the air operated valve. THE AIR
PRESSURE MUST NOT EXCEED 125 psi (8.6 bar).
The sensing valve should be installed in accordance
with the diagram shown in Figure 4. This system
depicts the additional use of a throttle control which
is optional. All adjustments must be made at normal
operating speeds.
a. Set the low pressure adjustment first by slowly
closing the nozzle to relieve the air pressure in the
AOV assembly.
b. Remove the AOV cap and O-ring (see Appendix E
for parts details).
c. Turn the low pressure adjustment stem counter-
clockwise to decrease the bypass pressure and
vice versa to increase the pressure.
d. Re-install the O-ring and AOV cap and tighten
securely.
e. Open and close the nozzle several times to ensure
proper setting and repeatability.
f. Slowly close the delivery nozzle again to relieve the
air pressure in the AOV assembly.
g. Remove the AOV cap and O-ring.
h. Adjust the locknuts clockwise to decrease delivery
flow rate and/or pressure and vice versa to increase
the flow rate. NOTE: Make sure the locknuts are
securely locked against each other before
re-installing the adjustment stem cap and
O-ring.
i. Slowly open the delivery nozzle and note delivery
flow rate and/or pressure.
j. Repeat steps g through i until desired flow rate
and/or pressure are achieved.
6. The speed of the pump may be increased as long as
it increases the flow through the delivery nozzle. It is
recommended to turn the pump at approximately 575
RPM for optimum performance. However, the pump
can be safely turned to 640 RPM if system conditions
permit (refer to Appendix B).
NOTE: IF PUMP SPEED IS INCREASED, BE CERTAIN
THE METER AND PIPING SYSTEM WILL HANDLE
THE INCREASED FLOW AND PRESSURE!
Chapter 3–Installation (Stationary)
NOTE: NEW PUMPS CONTAIN RESIDUAL TEST FLUID
SO IT MAY BE NECESSARY TO FLUSH THE PUMP
PRIOR TO USE. ALL PUMPS SHOULD BE INSTALLED
IN AN AREA THAT IS WELL VENTILATED.
The installation of the PT-Series pumps are simple.
However, in order for the pump to deliver optimum
performance, the principles discussed in this book
should be followed. The piping details provided illustrate
methods proved by hundreds of installations. Some
applications may require light variations, but every
effort should be made to follow the recommendations
identified in this manual.
The foundation for the pump is important. The foundation
must be firm, level, and made of concrete. The suggestions
in Figure 5 should be observed.
Pump base
1/2" x 8" anchor bolt
Metal wedge
Large washer
Concrete
Figure 5
3.1 Coupling alignment
For a long service life, the coupling alignment must be
near perfect. The shaft of the pump and driver are
carefully aligned at the factory but should always be
checked after the pump is installed and before the
initial operation.
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Lay a straight edge across both coupling halves on the
top and side. For proper alignment, both coupling faces
must be parallel and concentric (figure 1.6).
If misalignment exists, adjust the shims between the pump
and baseplate until exact alignment is accomplished.
Parallel Misalignment
Coupling faces are parallel but not concentric
Straight Edge
Angular Misalignment
Coupling faces are not parallel.
Straight Edge
If gap is more than 0.015",
then coupling alignment is out of tolerance
Proper Alignment
Coupling faces are parallel and concentric.
Straight Edge
Straight Edge
Figure 1.6
Scan QR Code and refer to the maintenance video titled “How
to Align the Coupling Between the Motor and Pump”.
No pump can discharge more liquid than it receives, so
the pump location and the inlet piping must be given
careful attention. If the inlet piping is unable to supply the
demand of the pump, expect trouble.
The installer and/or the user must take into account the
following:
• The pump must be located as near the storage tank as
possible. The complete inlet line, including the vertical line
from the tank must not exceed 12 feet (3.7 m) in length.
• The inlet must be the same size or next size larger than
the suction on the pump.
• Use an eccentric swage at the pump inlet nozzle to
change the line size (flat side up).
• Make certain the inlet line is level or sloped downward
to the pump.
• A strainer of the “Y” type, with 20 mesh screen or 1/16
in. perforated steel, must be on the inlet line of the
pump. (Mesh size indicates the number of openings per
lineal inch).
• Use a flexible connection in the pump inlet and outlet
piping to compensate for piping strains.
• The Inlet piping must be free of air leaks.
• All piping must be supported to avoid stress to the
pump casing.
• Potential risk due to local conditions regarding the
installation and operation (e.g. poor ventilation and
additional risks due to other elements in the vicinity, etc.).
• Qualification of the personnel.
• Type of liquid being transferred.
• Specific safety measures to be applied (e.g. gas
detection, automatic shut-off valves, personal protective
equipment, etc.).
3.2 Driver Installation
Wiring the electric motor correctly is extremely important
and must be done by a competent electrical contractor.
The following wire sizing chart indicates the minimum
standards for wire sizes.
Improper motor wiring causes expensive motor difficulties
from low voltage. The motors furnished with the stationary
pumps are usually dual voltage. If low voltage is suspected,
call the local power company and confirm the voltage
provided and wire accordingly. Connecting to improper
voltage will completely destroy the motor.
A humid climate can cause problems, particularly in
explosion proof motor applications. The normal breathing
of the motor, and alternating between being warm when
running and cool when stopped, often will cause moist
air to be drawn into the motor housing. This moist air will
condense, and may eventually add enough free water
to the inside of the motor to cause it to fail. To prevent
this, make a practice of running the motor and pump at
least once a week on a bright, dry day for an hour or so
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(pumping through the bypass system). In this period the
motor will heat up and vaporize the condensed moisture,
and drive it out of the motor. No motor manufacturer will
guarantee an explosion-proof or totally enclosed motor
against damage from moisture.
Engine drivers pose a special consideration. The
manufacturer’s instructions must be followed. When the
stationary pump is equipped with an engine from the
factory, the engine speed should normally not exceed
1,800 RPM. Excessive engine speed will overload the
engine and cause early failure. The engine loses 3% of
its power for every 1,000 ft (305 m) above sea level, so if
the installation is at a higher altitude than normal, consult
the factory.
Motor Recommended
wire size, AWG1
Hp Motor
phase Volts
Approximate
full load
amperes
Length of run (ft)
0–100 to 200 to 300
3 1 115 34.0 6 4 2
220 17.0 12 8 8
3230 9.6 12 12 12
460 4.8 12 12 12
5 1 115 56.0 4 1 1/0
230 28.0 10 6 4
3230 15.2 12 12 10
460 7.6 12 12 12
7-1/2 1230 40.0 8 6 4
3230 22.0 10 10 8
450 11.0 12 12 12
10 3230 28.0 8 8 8
460 14.0 12 12 12
15 3230 42.0 6 6 6
460 21.0 10 10 10
20 3 230 54.0 4 4 4
460 27.0 8 8 8
25 3230 68.0 2 2 2
460 34.0 6 6 6
30 3230 80.0 1 1 1
460 40.0 6 6 6
40 3230 100.0 2/0 2/0 2/0
460 52.0 4 4 4
50 3230 130.0 3/0 3/0 3/0
460 65.0 2 2 2
1 Based upon 3% voltage loss copper wire type TW. Single phase motor
calculations are based on two times distance.
Chapter 4–Operation (Stationary)
Performance curves are provided in Appendix C.
The following steps should be performed for the initial
pumping operation:
1. Make sure the strainer screen is clean.
2. Rotate the pump by hand.
3. Check V-belt drive or direct drive coupling alignment.
Misalignment will accelerate wear on the drive system,
motor bearings and pump.
4. Check motor for proper wiring.
5. Review complete system to make certain the function
of every valve and piece of equipment is clearly
understood. Everyone operating this system must be
properly trained in normal operating procedures and
emergency procedures in the event of a malfunction.
6. Close all hose valves.
7. Slowly open the storage tank bottom shut-off valve
(suction line to the pump). Immediately check the
system for leaks.
9. Record all pressure gauge readings, especially the
pressure gauge located at the discharge of the pump.
Start the pump and circulate the liquid through the
internal bypass valve.
10. Verify the proper pump rotation direction by referring
to the part details in Appendix E or the “Pump
Rotation” section at the beginning of this manual.
11. The pump has an internal bypass valve so it must
be adjusted to the required setting. The internal
bypass valve may be adjusted while the pump is in
operation by removing the bypass valve cap. Turning
the adjusting screw clockwise increases the internal
bypass valve pressure setting and counterclockwise
decreases the pressure setting.
12. An amp meter may be used by adjusting the bypass
valve until the amp meter indicates the full load motor
amperage rating shown on the motor nameplate or
maximum rated differential, whichever comes first. If
the motor overload protection device stops the motor
in this period the bypass valve setting is too high
and should be readjusted. After a satisfactory setting
is achieved, “seal” the bypass valve cap to prevent
tampering with the adjustment.
13. After initial operation, re-check the strainer screen.
Chapter 5—Maintenance of the
Pump System
PT-Series pumps require regular maintenance and care
like all mechanical equipment. A neglected or improperly
repaired pump will result in premature failure and cause
unsafe conditions. To promote product longevity and
safety, maintenance must be performed by properly
trained technicians. Make sure all safety systems are in
place and the system pressure has been relieved before
attempting ANY maintenance.
Normal wear parts are the mechanical shaft seals,
bearings, vanes, vane drivers and sideplates. All of
these parts plus O-rings and grease seals are offered in
the “repair kit.” Use only genuine Corken replacement
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parts when repairing the PT-Series pumps. Follow the
instructions provided with the parts.
When it becomes necessary to repair the pump or
remove it from the system, be absolutely certain that
all product being pumped is bled from the pump and
connected piping. Once all the product has safely been
bled from the pump and connected piping, make certain
no pressure is left in the system. SPECIAL CARE MUST
BE TAKEN DURING THE BLEED DOWN PROCESS TO
AVOID DANGER TO PERSONNEL AND PROPERTY
IN THE AREA. Take extra time to bleed the system
and make proper provisions to capture the product in
accordance with local regulations. ONLY A PROPERLY
TRAINED INDIVIDUAL SHOULD BE ALLOWED TO
BLEED A PUMPING SYSTEM.
5.1 Pump Maintenance Schedule
Make sure the transfer hoses are not “kinked”. A kinked
hose can cause excessive pump discharge pressure.
Always make sure the hoses are not out of date.
Daily Monthly 3 Months
Lubricate bearings •
Inspect drive coupling •
Clean inlet strainer •
Check for leaks •
Inspect hose and fittings •
5.2 Bearing Lubrication
NOTICE: AVOID ENTANGLEMENT IN MOVING PARTS.
DO NOT LUBRICATE PUMP BEARINGS, HYDRAULIC
ADAPTER COUPLING OR ANY OTHER PARTS WHILE
THE PUMP IS ACTIVE.
There are two lubrication points in which to grease
the pump bearings; one zerk per bearing cap located
at opposite ends of the pump. Two grease relief and
ventilation fittings have been provided—one at each
end of the pump—to help prevent over greasing the
bearings. Over greasing can cause seal failure if grease
passageways are blocked in some way. Remove relief
fittings or confirm free movement of relief prior to
greasing bearings. Clean each fitting before lubricating
the bearings. This practice helps to prevent foreign
material contamination of the bearings and accidental
over-pressurization of the mechanical seals. Use only
NLGI grade 2 ball bearing grease.
Lubricate ball bearings and hydraulic motor couplings (if
equipped) a minimum of every three months.
Greasing Procedure:
1. Remove grease relief fittings from bearing covers or
hydraulic motor adapter.
2. Grease with a hand gun until grease escapes from
grease relief fitting port.
3. Return grease relief fittings to bearing covers.
DO NOT over grease pump bearings. Some grease will
escape from the grease tell-tale hole after lubrication.
This is normal, but excessive grease on pumps that use
mechanical seals can cause seal failure.
5.4 Strainers
Clean strainers regularly to avoid pump starvation.
Intervals between cleaning depend upon the application
and conditions.
5.5 Disassembly Instructions
1. Truck engine must be turned off and PTO disengaged.
2. Bleed all product from the system as described above.
NOTE: There is a 1/4 in. NPT connection at the bottom
of some models that allow easy pump drainage.
3. Remove the PTO shaft or hydraulic drive motor,
adapter, and coupling.
NOTICE: ADHERE CLOSELY TO ALL HAZARD
WARNINGS AND INSTRUCTIONS IN THE
“MAINTENANCE” SECTION OF THIS MANUAL.
4. Carefully clean the pump shaft. Begin at one end of
the pump, and make certain that the shaft is free of
nicks and burrs to prevent damage to the mechanical
seal when removing the head assembly.
5. Unscrew the bearing cover bolts and pull the bearing
cover and gasket off the shaft. Dispose of the bearing
cover gasket.
6. Unscrew the opposite bearing cover bolts and pull the
bearing cover and gasket off the shaft. Dispose of the
bearing cover gasket.
7. Remove the locknuts and lockwashers in place:
a. Bend the lockwasher tab up and unscrew the
locknut counterclockwise and remove it from the
shaft.
b. Pull the lockwasher off the shaft. Check the
lockwasher for damage and replace if needed.
c. Repeat steps a and b on the opposite end of the
shaft.
8. Unscrew the head bolts and carefully pry the head
from the pump casing.
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9. Pull the head off the shaft. The head O-ring, bearing
and mechanical seal will come off with the head
assembly. Detach and dispose of the head O-ring.
a. Take the bearing out of the housing in the head.
b. Remove the mechanical seal. Using two
screwdrivers, gently push the backside of the seal
jacket to remove the seal from the head (see Figure
7). Be careful when using the screwdrivers on the
seal faces. The seal faces can be damaged. Detach
and dispose of the mechanical seal O-rings.
Seal jacket
driver tabs
Seal jacket
Figure 7
10. Remove the rotor and shaft from the pump casing.
While removing the shaft, cup one hand underneath
the rotor so the vanes and vane drivers do not fall
out. Carefully set aside the rotor and shaft, vanes and
vane drivers for future reassembly.
11. Repeat steps 8 and 9 above to remove the remaining
components from the opposite side of the pump.
5.6 Assembly Instructions
Before reassembly, check each component part for wear
or damage. If necessary, replace flawed parts. Wash
out the bearing/seal recess of the head and remove any
burrs or nicks from the rotor and shaft.
1. Reassemble the first side of the pump by inserting a
new head O-ring into the groove of the head. Lightly
lubricate the O-ring to facilitate installation. Start on
one side of the groove and stretch the O-ring into the
groove (see Figure 8).
Figure 8
2. Attach the head to the pump casing. Insert four head
bolts 90° apart and tighten to 25 ft•lbs (34 Nm).
3. Mechanical Seal
Apply a small amount of light oil in the head recess.
Press the mechanical seal assembly into the recess of
the head so the seal jacket drive tabs face the rotor.
The pin in the stationary seat must be between the
lugs in the back of the head recess (see Figure 7).
4. Hand pack the ball bearing with grease. See the
“Bearing Lubrication” section for recommended
grease.
5. Insert the bearing into the head recess. The bearing
balls should face outward, and the grease shield
should face inward. Make sure the bearing is square
and completely seated against the mechanical seal.
6. Turn the pump casing around to reassemble the
opposite side.
7. Place vanes into the upper rotor-shaft slots. Ensure
the curved tip of each vane faces radially outward and
all in the same direction of rotation (see Figure 10).
8. While cupping these vanes in place, rotate the rotor-
shaft over 180° and install the vane drivers.
9. Place rotor-shaft and vane assembly into pump
case with the vanes on the bottom. Ensure the ribs
in the vanes face the direction of pump rotation
(see Appendix E for parts details and pump
rotation arrows).
10. Place the remaining vanes into the upper rotor-shaft
slots facing the same direction as the first vanes.
11
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11. Install the remaining head, mechanical seal, and
bearing as mentioned in steps 1 through 5. Apply a thin
coating of motor oil to the shaft to facilitate installation.
12. Rotate the shaft by hand to engage the seal jacket
driver tabs. Check for binding or tight spots. If the
rotor does not turn freely, use a soft faced mallet and
lightly tap the rims of the heads until the rotor is in the
correct position. Tighten all remaining head bolts for
each head to 25 ft•lbs (34 Nm) of torque.
13.Locknut Installation
All bearing locknuts and lockwashers MUST be
positioned and adjusted properly. Overtightening
locknuts can lead to bearing failure or broken lockwasher
tabs. If locknuts are loose, the rotor will shift against the
heads and cause considerable wear (see Figure 9).
1 stop
equals
.001 in.
rotor
movement
2 stops equals one
tab (.002 in.)
B
A(Inner tab fits
in rotor slot)
Locknut
Lockwasher
Figure 9: Locknut and lockwasher adjustment
a. On both ends of the pump shaft, slide on a lockwasher,
with the tabs facing outward, and then tighten a
locknut with the tapered end inward. Make sure the
inner tab (A) of the lockwasher is inserted in the slot of
the shaft threads. Bend slightly, if necessary.
b. Carefully tighten both locknuts until the bearings
have reached the bottom of the head recess. DO
NOT overtighten, Make sure the inner tab of the
lockwasher does not shear.
c. Loosen both locknuts one complete turn.
d. Tighten one locknut until a slight rotor drag can be
felt while turning the shaft by hand.
e. Back the locknut off one width of the lockwasher
tab (B). To secure the locknut, bend the closest
aligned lockwasher tab into the slot of the
locknut. The pump should now turn freely when
rotated by hand.
f. Hand-tighten the opposite locknut until it is snug
against the bearing. Then, with a spanner wrench,
tighten the locknut one width of the lockwasher tab.
Tighten just past the tab width and then back off
the locknut until the tab is aligned with the slot of
the locknut. To secure the locknut, bend the aligned
lockwasher tab into the slot of the locknut. The
pump should still turn freely when rotated by hand.
g. Check the adjustment. The locknut and lockwasher
should turn back and forth by hand. If this is not
possible, one or both locknuts are too tight. They
must be alternately loosened one stop at a time
(.001 in.) (25 microns). Begin with the locknut
adjusted last.
14. If equipped with the standard bypass valve, remove
the bypass valve cap and turn the adjustment screw
counterclockwise to relieve the spring tension.
Remove the four 3/8 in. bolts from the bypass valve
cover. Use caution as a small amount of spring
tension will remain on the bypass valve spring
before complete bolt removal. Inspect bypass
valve, spring, and bypass valve cap gasket for wear,
abrasions, etc. Replace if damage is found.
15. If equipped with an Air Operated Valve (AOV), ensure
the air supply pressure has been relieved and the
supply line disconnected from the valve housing.
Remove the AOV cap and discard the O-ring from
underneath. Remove the retainer ring and locknuts
from the adjustment stem. Remove the four 3/8
in. bolts and lockwashers from the AOV housing.
Carefully remove the AOV assembly from the pump.
Remove and discard the gasket and clean the gasket
areas. Remove the two recessed-head machine
screws and the diaphragm cover plate. Slide the
diaphragm assembly out from the housing. Remove
the intermediate vent plate from between the two
diaphragms. Inspect the diaphragms, spring, and
valve for abrasions and replace if necessary.
5.7 Vane Replacement
NOTICE: ONLY QUALIFIED TECHNICIANS SHOULD
PERFORM MAINTENANCE AND THEY MUST
FOLLOW THE APPROPRIATE PROCEDURES AND
WARNINGS PRESENTED IN MANUAL.
1. Follow steps 2–6 in the “Pump Disassembly
Instructions” section of this manual to remove the
head assembly from the non-PTO side of the pump.
2. Rotate the shaft until a vane is in the top (12 o’clock)
position of the rotor. Remove the vane.
3. Position a new vane so the rounded edge faces out
from the pump and the relief grooves face towards the
direction of rotation (see Figure 10).
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4. Repeat steps 2 and 3 until all vanes have been replaced.
5. Follow steps 2–7 and 12–13 of the “Pump Assembly
Instructions” section of this manual to reassemble
the pump.
Relief grooves
face the direction
of rotation
Rounded edge out
Figure 10: PT30 model shown above
5.8 Bypass Valve Assembly
1. Place the bypass valve into the bypass valve bore of
the pump casing with the fluted end inward.
2. Insert the bypass valve spring and spring guide
against the bypass valve.
3. Attach a new bypass valve gasket and the bypass
valve cover onto the pump casing.
4. Tighten the bypass valve adjusting screw into the
bypass valve cover until it makes contact with the
spring guide.
NOTICE: THE BYPASS VALVE SETTING MUST BE
TESTED AND PROPERLY ADJUSTED BEFORE
PUTTING THE PUMP INTO SERVICE. PLEASE SEE
“BYPASS VALVE ADJUSTMENT”.
5. After the bypass valve has been adjusted correctly,
attach the bypass valve cap and gasket.
5.9 Air Operated Valve (AOV)
Assembly
1. Install the intermediate vent plate between the two
diaphragms ensuring proper orientation with the
screw holes in the housing. Slide the diaphragm
assembly into the housing and install the diaphragm
cover plate and recessed-head machine screws and
tighten securely. Install this assembly with the valve,
spring, and gasket to the pump using the four 3/8 in.
bolts and lock washers and torque to 15 ft•lbs. Install
both locknuts all the way down the adjustment stem
and replace the retainer ring. Install the new O-ring
and AOV cap. Refer to Air Operated Valve Adjustment
for adjustment procedure.
2. Grease bearings per the instructions listed in the
Pump Maintenance schedule.
3. Install the pump according to the installation guidelines
mentioned previously.
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Chapter 6–Repair Kits
PT20 Repair Kit 4771-X1_2 a
Part Number Description Qty.
2-258_ a O-ring 2
4648 Ball bearing 2
4678 Vane driver 2
4677 Vane 4
4634-X_2 a Seal assembly 2
4654 Shaft lockwasher 2
4655 Shaft locknut 2
4650 Grease seal 2
4657 Bearing cap gasket 2
4688 Flange gasket 2
4659 Bypass valve cap gasket 1
4767 Bypass valve cover gasket 1
4653 Shaft key 1
ID108 I.O.M. manual 1
PT25 Repair Kit 4770-X1_2 a
Part Number Description Qty.
2-258_ a O-ring 2
4648 Ball bearing 2
4652 Vane driver 3
4696 Vane 6
4634-X_2 a Seal assembly 2
4654 Shaft lockwasher 2
4655 Shaft locknut 2
4650 Grease seal 2
4657 Bearing cap gasket 2
4658 Flange gasket 2
4659 Bypass valve cap gasket 1
4660 Bypass valve cover gasket 1
4653 Shaft key 1
ID108 I.O.M. manual 1
PT30 Repair Kit 4769-X1_2 a
Part Number Description Qty.
2-266_ a O-ring 2
5584 Ball bearing 2
5589 Vane driver 3
5588 Vane 6
4621-X_2 a Seal assembly 2
5591 Shaft lockwasher 2
5592 Shaft locknut 2
5586 Grease seal 2
5596 Flange gasket 2
5595 Bearing cap gasket 2
5597 Bypass valve cap gasket 1
5578 Bypass valve cover gasket 1
2270 Shaft key 1
ID108 I.O.M. manual 1
a See material code chart.
b Registered trademark of the DuPont company. Material Code
ABuna-N
DViton ®b
14
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Appendix A—Model Number Identification Code and Available Options
PT-Series (Double Shaft)
Appendices
A. Model Number Identification Code and Available Options
Base Model PT20 PT25 PT30
Base Model
(with hydraulic
drive option)
PTH20 PTH25 PTH30
Specification Fields
Strainer No strainer Standard Standard Standard N
With strainer Option Option Option S
Internal Bypass
Valve
Bypass valve Standard Standard Standard S
Air Operated
Valve (AOV) Option Option Option A
Bypass Valve
Spring
35–50 psi Option Not applicable Not applicable 4
50–75 psi Option Not applicable Not applicable 1
75 –110 p si Standard Not applicable Not applicable 2
110 –125 ps i Option Not applicable Not applicable 3
50 –110 psi Not applicable Standard Standard 2
110 –125 ps i Not applicable Option Option 3
Seal O-ring
Material
Buna-N Standard Standard Standard A
Viton ®a Option Option Option D
Seal Seat
Material Cast iron Standard Standard Standard 2
Inlet Flange
2 in. NPT Standard Optional Not applicable E
2.5 in. NPT Not applicable Standard Not applicable J
3 in. NPT Not applicable Not applicable Standard P
2 in. weld Optional Not applicable Not applicable F
2.5 in. weld Not applicable Optional Not applicable K
3 in. weld Not applicable Not applicable Optional Q
Less flange Optional Optional Optional X
Outlet Flange
2 in. NPT Standard Optional Not applicable E
2.5 in. NPT Not applicable Standard Not applicable J
3 in. NPT Not applicable Not applicable Standard P
2 in. weld Optional Not applicable Not applicable F
2.5 in. weld Not applicable Optional Not applicable K
3 in. weld Not applicable Not applicable Optional Q
Less flange Optional Optional Optional X
Strainer Assembly b
Pump Model Strainer Assembly Part Number
PT/PTH20 4684-X
PT/PTH25 4689-X
PT/PTH30 4680-X
a Registered trademark of the DuPont company.
b Strainer assembly ordered by part number when not assembled to the pump.
Air Operated Valve Assembly (AOV)
Pump Model AOV Part Number
PT/PTH20 5470-1XA (Buna-N)
PT/PTH25 5462-1XA (Buna-N)
PT/PTH30 5566-1XA (Buna-N)
15
Model Number
Base X X X X X X X
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Appendix B—Specifications
Operating Specifications
Standard connections: 2 in., 2-1/2 in., and 3 in. NPT
Optional connections: Slip-on weld
Maximum differential pressure: 125 psid (8.6 bar)
Temperature range: -25° to 300°F (-32° to 149°C)
Maximum working pressure: 200 psi (13.8 bar)
Maximum speed: 780 RPM—all models 20 and 25
640 RPM—all models 30
Maximum flow: Up to 271 GPM (1,026 L/min)
Maximum viscosity: 20,000 SSU (4,250 cP)
Fluids: Refined petroleum products, industrial solvents, and other fluids
Material Specifications
Part Standard Material Optional Material
Case Cast iron ASTM A48
Head Cast iron ASTM A48
Flanges Cast iron ASTM A48
Rotor Ductile iron ASTM A536
Bearing cap Steel
Bearing cover / spacer with hydraulic
motor adapter (cast aluminum) and
coupling (steel)
Bearings Ball (single row), grease lubricated to 300°F
(149°C) Max.
Vanes Full size with 316 stainless steel wear plate to
240°F (115°C); 20,000 SSU (4,250 cP) max.
Bypass valve Cast iron ASTM A48 electroless nickel plated
Bypass/AOV cap Cast iron ASTM A48
Bypass valve cover Cast iron ASTM A48
Bypass valve spring Plated steel
Bypass valve spring ranges 35–125 psi (2.4–8.6 bar)
Seal seat Cast iron Stainless steel and Ni-Resist
Seal metal parts Steel
Shaft Keyed shaft, high strength steel
O-rings Buna-N to 240°F (115°C) Viton®2 to 300°F (149°C)
Gaskets Composition to 500°F (260°C)
Vane drivers Case hardened steel
Gage ports 1/4 in. NPT
1 Registered trademark of the DuPont company.
B. Specifications
16
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C. Performance
Appendix C—Performance Curves
PT/PTH20 Pump 1
10
20
30
40
50
60
70
80
90
0
1
2
3
4
5
6
7
8
1251007550250
Differential Pressure (psi)
Capacity (gpm)
Horsepower (hp)2
275
420
520
640
780
275
420
520
640
780
PT/PTH25 Pump 1
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
0
1
2
3
4
5
6
7
8
1251007550250
Differential Pressure (psi)
Capacity (gpm)
420
520
640
780
Horsepower (hp)2
420
520
640
780
275
9
10
11
12
13
275
14
15
16
Viscosity Chart
Viscosity (SSU) 100 1,000 5,000 10,000 20,000
Maximum RPM 780 640 520 420 275
1 These curves depict performance of the PUMP ONLY. Performance will vary in applications due to system design and variables. Approximate capacities and
horsepowers are based on 30 SSU (3 cP) fluid.
2 Torque (in•lb) = hp x 63025
RPM
17
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Appendix C—Performance Curves
PT/PTH30 Pump 1
90
100
110
120
130
140
150
160
170
180
190
200
210
220
230
240
280
260
250
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
19
270 18
17
16
0
1251007550250
Differential Pressure (psi)
Capacity (gpm)
275
350
420
520
640
Horsepower (hp)2
275
350
420
520
640
290
300 21
20
Viscosity Chart
Viscosity (SSU) 100 1,000 5,000 10,000 20,000
Maximum RPM 780 640 520 420 275
1 These curves depict performance of the PUMP ONLY. Performance will vary in applications due to system design and variables. Approximate capacities and
horsepowers are based on 30 SSU (3 cP) fluid.
2 Torque (in•lb) = hp x 63025
RPM
18
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D. Outline Dimensions
All dimensions are in inches (millimeters).
8.000
(20.32)
8.000
(203.2)
1.750
(44.5)
6.079
(154.4)
1.500
(38.1)
4.125
(104.8)
4.984
(126.6)
2.500
(63.5)
3.307
(84.0)
3.307
(84.0)
3.904
(99.2)
3.904
(99.2)
2.500
(63.5)
Ø.44
(11.2)
4 holes
.500
(12.7)
1.750
(44.5)
0.813
(20.6)
0.813
(20.6)
4.000
(101.6)
5.181
(131.6)
1.125
(28.6)
5.300
(134.6)
3.629
(92.2)
Appendix D—Outline Dimensions for the PT20
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All dimensions are in inches (millimeters).
4.000
(101.5)
5.475
(139.1)
8.750
(222.3)
6.798
(172.7 )
0.250
(6.4)
1.750
(44.5)
6.348
(161.2)
5.063
(128.6)
2.750
(69.9)
2.750
(69.9)
3.500
(88.9)
3.500
(88.9)
3.886
(98.7)
4.313
(109.5)
1.500
(3 8.1)
1.500
(3 8.1)
2.446
(6 2.1)
2.446
(6 2.1)
6.048
(153.6)
Ø 1.125
(28.6)
Ø .44
(11.2)
4 holes
9.445
(239.9)
Appendix D—Outline Dimensions for the PT25
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