SANDPIPER PB1-A User Manual

SERVICE AND OPERATING MANUAL

®

Model PB1-A

Type 3

PLEASE NOTE!

The photos shown in this manual are for general instruction only. YOUR SPECIFIC
MODEL MAY NOT BE SHOWN. Always refer to the parts list and exploded view
drawing for your specific model when installing, disassembling or servicing your
pump.

PRINCIPLE OF PUMP OPERATION

This ball type check valve pump is powered by compressed air and is a 1:1
pressure ratio design. It alternately pressurizes the inner side of one diaphragm
chamber, while simultaneously exhausting the other inner chamber. This causes the
diaphragms, which are connected by a common rod, to move endwise. Air pressure
is applied over the entire surface of the diaphragm, while liquid is discharged from the
opposite side. The diaphragm operates under a balanced condition during the
discharge stroke, which allows the unit to be operated at discharge heads over 200
feet (61 meters) of water head.

Since the diaphragms are connected by a common rod, secured by plates to the
center of the diaphragms, one diaphragm performs the discharge stroke, while the
other is pulled to perform the suction stroke in the opposite chamber.

For maximum diaphragm life, keep the pump as close to the liquid being pumped
as possible. Positive suction head in excess of 10 feet of liquid (3.048 meters) may
require a back pressure regulating device. This will maximize diaphragm life.

Alternate pressuring and exhausting of the diaphragm chamber is performed by
means of an externally mounted, pilot operated, four-way spool type air distribution
valve. When the spool shifts to one end of the valve body, inlet air pressure is applied
to one diaphragm chamber and the other diaphragm chamber exhausts. When the
spool shifts to the opposite end of the valve body, the porting of chambers is reversed.
The air distribution valve spool is moved by an internal pilot valve which alternately
pressurizes one side of the air distribution valve spool, while exhausting the other side.
The pilot valve is shifted at each end of the diaphragm stroke by the diaphragm plate
coming in contact with the end of the pilot spool. This pushes it into position for shifting
of the air distribution valve.

The chambers are manifolded together with a suction and discharge check valves
for each chamber, maintaining flow in one direction through the pump.

INSTALLATION & START-UP

Locate the pump as close to the product being pumped as possible, keeping
suction line length and number of fittings to a minimum. Do not reduce line size.

For installations of rigid piping, short flexible sections of hose should be installed
between pump and piping. This reduces vibration and strain to the piping system. A
Warren Rupp surge suppressor is recommended to further reduce pulsation in flow.

This pump was tested at the factory prior to shipment and is ready for operation.
It is completely self-priming from a dry start for suction lifts of 10-15 feet (3 to 4.5
meters) or less. For suction lifts exceeding 15 feet of liquid, fill the chambers with liquid
prior to priming.

AIR SUPPLY

Air supply pressures cannot exceed 100 psi (7 bar). Connect the pump air inlet
(see Fig. 1) to an air supply of sufficient capacity and pressure required for desired
performance. When the air line is solid piping, use a short length of flexible hose not
less than
The weight of the air supply line and of the filter must be supported by some means
other than the air valve cap. Failure to provide support may result in damage to the
pump. A pressure regulating valve should be installed to prevent pressure from
exceeding recommended limits.

3

/4" (19mm) in diameter between pump and piping to eliminate strain to pipes.

CAUTION

Hydrofluoric acid above 40% concen­trate should not be pumped with this
unit. Check chemical compability chart
for other fluids.

CAUTION

Maximum Operating Pressure, 100 P.S.I.
(7 Bar.) and Safe Operating Temp­eratures of 150°F. (66°C.) Maximum and
40°F. (4.4°C.) Minimum are based upon
mechanical stress only and may be
significantly altered by pumping certain
chemicals. Consult engineering guides
for chemical compatibilities and
temperature limits.

IMPORTANT

Read these instructions completely,
before installation and start-up. It is the
responsibility of the purchaser to retain
this manual for reference. Failure to
comply with the recommendations
stated in this manual will damage the
pump, and void factory warranty.

WARNING

Take action to prevent static sparking.
Fire or explosion can result, especially
when handling flammable liquids. The
pump, piping, valves, containers or other
miscellaneous equipment must be
grounded.

BEFORE OPERATION

Before pump operation, inspect all
gasketed fasteners for looseness caused
by gasket creep. Retorque loose fasten­ers to prevent leakage. Follow recom­mended torques stated in the card at­tached to the new pump.

DANGER

Before doing any maintenance on the
pump, be certain all pressure is com­pletely vented from the pump, suction,
discharge, piping, and all other open­ings and connections. Be certain the air
supply is locked out or made non­operational, so that it cannot be started
while work is being done on the pump.
Be certain that approved eye protection
and protective clothing are worn at all
times in the vicinity of the pump. Failure
to follow these recommendations may
result in serious injury or death.

Warren Rupp, Inc., A Unit of IDEX Corp • P.O. Box 1568 • Mansfield, Ohio 44901-1568 USA • [phone] • Fax [phone]
520-032-000 5/99 PB1-A Type 3 Page 1

AIR INLET & PRIMING

For start-up, open an air valve approximately 1/2 to 3/4 turn. After the unit primes,
an air valve can be opened to increase flow as desired. If opening the valve increases
cycling rate, but does not increase flow rate, cavitation has occurred, and the valve
should be closed slightly.

For the most efficient use of compressed air and the longest diaphragm life, throttle
the air inlet to the lowest cycling rate that does not reduce flow.

AIR EXHAUST

If a diaphragm fails, the pumped liquid or fumes can enter the air end of the pump,
and be exhausted into the atmosphere. When pumping hazardous or toxic materials,
pipe the exhaust to an appropriate area for safe disposition (see Fig. 2).

This pump can be submerged if materials of construction are compatible with the
liquid. The air exhaust must be piped above the liquid level. Piping used for the air
exhaust must not be smaller than 1" (2.54 cm). Reducing the pipe size will restrict air
flow and reduce pump performance. When the product source is at a higher level than
the pump (flooded suction), pipe the exhaust higher than the product source to
prevent siphoning spills.

Freezing or icing of the air exhaust can occur under certain temperature and
humidity conditions. Use of a Warren Rupp Air Dryer unit should eliminate most icing
problems.

BETWEEN USES

When used for materials that tend to settle out or transform to solid form, the pump
should be completely flushed after each use, to prevent damage. Product remaining
in the pump between uses could dry out or settle out. This could cause problems with
valves and diaphragms at re-start. In freezing temperatures, the pump must be
drained between uses in all cases.

Fig. 1 Air inlet

DIAPHRAGM SERVICING

Remove the four V-Band clamps securing the manifold assemblies to the outer
chambers. Remove the two V-Band clamps securing the outer chambers to the inner
chambers. Remove the diaphragm assembly (outer plate, diaphragm, inner plate) by
turning the assembly counterclockwise using a
lugs. (If a socket is used, it must be a six point socket.)

The diaphragm assembly has been secured to the diaphragm rod with LOCTITE
242 Blue. This is to eliminate movement. During diaphragm servicing, the outer
diaphragm plate can be removed by turning the assembly counterclockwise, using a

7

/8" (2.22 cm) wrench on the outer diaphragm plate lug. (If a socket is used, it must
be a six point socket.) To replace the interior components consisting of shaft seals,
sleeve bearings and bearing retainers, the inner chambers must be disassembled
from the intermediate bracket by removing six capscrews.

7

/8" (2.22 cm) wrench on the outer plate

CHECK VALVE SERVICING

Need for inspection or service is usually indicated by poor priming, unstable

cycling, reduced performance or the pump’s cycling but not pumping.

Remove the four V-Band clamps securing the manifold assemblies to the outer
chambers. Inspect the surfaces of both check valve and seat for wear or damage that
could prevent proper sealing. If pump is to prime properly, valves must seat air tight
(see Fig. 3).

REASSEMBLY

To reassemble the diaphragm assembly, the threads of the outer diaphragm plate
must have LOCTITE 242 Blue applied to the threads before threading into the
diaphragm rod. Torque the diaphragm assembly to 25 ft. lbs. (33.90 Newton meters)
(see Fig. 4). Allow a minimum of 15 minutes to elapse after torquing, then re-torque
diaphragm assembly to 25 ft. lbs., compensating for stress relaxation in the clamped
assembly.

During reassembly make certain that the rubber bumper is on the rod at each side.
Install the diaphragm with the natural bulge outward as indicated on the diaphragm.
Install the outer diaphragm plate on the outside of the diaphragm and make certain
that the large radius side of the inner plate is toward the diaphragm. Tighten the outer
diaphragm plate to approximately 25 ft. lbs. (33.90 Newton meters). Torque while

Fig. 2 Exhaust muffler

Fig. 3 Gaskets in place before reassembly

Fig. 4 Torquing of diaphragm

PB1-A Type 3 Page 2 520-032-000 5/99

allowing the diaphragm to turn freely with plates. Use a wrench on the outer diaphragm
plate of the opposite side to keep rod from rotating. If the opposite chamber is
assembled, the rod need not be held.

A Note about Air Valve Lubrication

The pump’s pilot valve and main air valve assemblies are designed to operate
WITHOUT lubrication. This is the preferred mode of operation. There may be
instances of personal preference, or poor quality air supplies when lubrication of the
compressed air supply is required. The pump air system will operate with properly
lubricated compressed air supplies. Proper lubrication of the compressed air supply
would entail the use of an air line lubricator (available from Warren Rupp) set to deliver
one drop of 10 wt., non-detergent oil for every 20 SCFM of air the pump consumed
at its point of operation. Consult the pump’s published Performance Curve to
determine this.

It is important to remember to inspect the sleeve and spool set routinely. It should
move back and forth freely. This is most important when the air supply is lubricated.
If a lubricator is used, oil accumulation will, over time, collect any debris from the
compressed air. This can prevent the pump from operating properly.

Water in the compressed air supply can create problems such as icing or freezing
of the exhaust air causing the pump to cycle erratically, or stop operating. This can
be addressed by using a point of use air dryer (available from Warren Rupp) to
supplement a plant’s air drying equipment. This device will remove excess water from
the compressed air supply and alleviate the icing or freezing problem.

Externally Serviceable Air Distribution System

Please refer to the exploded view drawing and parts list in the Service Manual
supplied with your pump. If you need replacement or additional copies, contact your
local Warren Rupp Distributor, or the Warren Rupp factory Literature Department at
the number shown below. To receive the correct manual, you must specify the
MODEL and TYPE information found on the name plate of the pump.

Fig. 5 Pilot valve, sleeve and spool

Fig. 6 Torquing air inlet capscrews

Models with 1" suction/discharge or larger, and METAL center sections:

The main air valve sleeve and spool set is located in the valve body mounted on
the pump with four hex head capscrews. The valve body assembly is removed from
the pump by removing these four hex head capscrews.

With the valve body assembly off the pump, access to the sleeve and spool set
is made by removing four hex head capscrews (each end) on the end caps of the valve
body assembly. With the end caps removed, slide the spool back and forth in the
sleeve. The spool is closely sized to the sleeve and must move freely to allow for
proper pump operation. An accumulation of oil, dirt or other contaminants from the
pump’s air supply, or from a failed diaphragm, may prevent the spool from moving
freely. This can cause the spool to stick in a position that prevents the pump from
operating. If this is the case, the sleeve and spool set should be removed from the
valve body for cleaning and further inspection.

Remove the spool from the sleeve. Using an arbor press or bench vise (with an
improvised mandrel), press the sleeve from the valve body. Take care not to damage
the sleeve. At this point, inspect the o-rings on the sleeve for nicks, tears or abrasions.
Damage of this sort could happen during assembly or servicing. A sheared or cut o­ring can allow the pump’s compressed air supply to leak or bypass within the air valve
assembly, causing the pump to leak compressed air from the pump air exhaust or not
cycle properly. This is most noticeable at pump dead head or high discharge pressure
conditions. Replace any of these o-rings as required or set up a routine, preventive
maintenance schedule to do so on a regular basis. This practice should include
cleaning the spool and sleeve components with a safety solvent or equivalent,
inspecting for signs of wear or damage, and replacing worn components.

To re-install the sleeve and spool set, lightly lubricate the o-rings on the sleeve with
an o-ring assembly lubricant or lightweight oil (such as 10 wt. air line lubricant). Re­install one end cap, gasket and bumper on the valve body. Using the arbor press or
bench vise that was used in disassembly,

carefully press the sleeve back into the valve
body, without shearing the o-rings. You may have to clean the surfaces of the valve
body where the end caps mount. Material may remain from the old gasket. Old
material not cleaned from this area may cause air leakage after reassembly. Take

Fig. 7 Pilot valve being removed

Fig. 8 Bushings, o-rings, and retainers

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