SANDPIPER MSA25 - Manual (Page 5)

Model MSA1, MSA25 Type 4 Page 4 msa1dl4sm-rev0711
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 flap swing 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 per-
formed 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 valve spool. This pushes it into position for shifting of the air
distribution valve.
The chambers are manifolded together with a suction and discharge check valve 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 Tranquilizer ® 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 com-
pletely self-priming from a dry start for suction lifts of 5-7 feet (1.5-2 meters) or less. For suction
lifts exceeding 10 feet of liquid, fill the chambers with liquid prior to priming.
CHAMBER PORTING
MSA1 with bottom chamber porting of check valve manifolding is recommend-
ed for general portable pumping applications, low head transfer pumping, and for
pumping solids-laden liquids which tend to settle out.
For low flow, high pressure applications and for pumping highly viscous liquids, top porting
of chamber to check valve manifold is recommended. Model MSA1 MARATHON with flap type
valves can be arranged in either bottom chamber porting or top chamber porting of check valve
manifold simply by rotating outer diaphragm chambers 180° and reversing the flap valves and
seats in the manifold so they remain in the proper operating position—hanging downward. Make
certain that the flap valves are opening outward from the manifold.
Note: Low profile mounting feet are available when the top porting configuration is used.
SERVICE AND OPERATING MANUAL
Model MSA1
Model MSA25
Type 4
II 2GD T5
See Explanation of
ATEX Certification Page