SANDPIPER SET2-A - Manual (Page 4)

Page 4 Model SET2-A Type 3 520-117-000 5/99
Procedures for reassembling the diaphragms are the reverse of the above. The
diaphragms must be installed with their natural bulge to the outside, toward the outer
diaphragm plate. Install the inner plate with the flat face against the diaphragm.
After all components are in position in a vise and hand tight, tighten with a wrench
to approximately 40 ft. lbs. (5.53 kilograms/meters) torque. After both diaphragm
assemblies have been assembled, thread one assembly into the shaft (hold the shaft
near the middle in a vise with soft jaws, to protect the finish). Install this subassembly
into the pump and secure by placing the outer chamber on the end with the diaphragm.
This holds the assembly in place while the opposite side is installed. Torque the last
diaphragm assembly to 30 ft. lbs. (4.147 kilograms/meters). This final torquing will lock
the diaphragm assemblies together. Place the remaining outer chamber on the open
end and loosely tighten the bolts. Replace the manifold assemblies to square the flanges
before final tightening of the remaining bolts, alternating for progressive tightening, the
eight capscrews that secure outer chamber to inner chamber.
Make sure the o-ring between the Teflon driver chamber and Teflon driver diaphragm is
in place before final torquing of the eight capscrews that hold the chambers together.
MAiNTENANcE AfTEr USE
When the pump is used for materials that tend to settle out or transform from liquid
to solid form, care must be taken after each use or during idle time to remove them and
flush the pump as required to prevent damage.
In freezing temperatures the pump must be completely drained when idle. This model
must be tilted to allow the liquid from the chambers to run out of the discharge port.
MAiNTENANcE NOTE
A preventative maintenance procedure should be established to check the Teflon
diaphragms for breakage. Even though this part was proven to be good for millions of
cycles, each application may present its own problems.
The choice of the Teflon unit would tend to show that the material being handled
would not be compatible with the standard Neoprene or other rubber. If a Teflon diaphragm
were to break, the unit would continue pumping via the driver diaphragm. In a standard
SandPIPER, a ruptured diaphragm would show up as air bubbles in media being pumped
or pumped material being blown out the exhaust muffler. These events would not occur in
the Teflon unit until the material in the driver diaphragm had been attacked and destroyed.
If it were to reach that point, the pump as a whole would stand a chance of being lost
instead of just a diaphragm.
SErVicE iNSTrUcTiONS:TrOUBLE SHOOTiNG
1. Pump will not cycle
A. Check to make sure the unit has enough pressure to operate and that the air inlet
valve is open.
B. Check the discharge line to insure that the discharge line is neither closed nor
blocked.
C. If the spool in the air distribution valve is not shifting, check the main spool. It must
slide freely.
D. Excessive air leakage in the pump can prevent cycling. This condition will be
evident. Air leakage into the discharge line indicates a ruptured diaphragm. Air leakage
from the exhaust port indicates leakage in the air distribution valve. See further service
instructions.
E. Blockage in the liquid chamber can impede movement of diaphragm.
F. Plugged or dirty exhaust muffler.
2. Pump cycles but will not pump
A. Suction side of pump pulling in air. Check the suction line for air leaks and be sure
that the end of the suction line is submerged. Check flange bolting. Check valve flanges
and manifold to chamber flange joints.
B. Make certain the suction line or strainer is not plugged. Restriction at the suction
is indicated by a high vacuum reading when a vacuum gauge is installed in the suction
line.
C. Check valves may not be seating properly. To check, remove the suction line and
cover the suction port with your hand. If the unit does not pull a good suction (vacuum),
the check valves should be inspected for proper seating.
D. Static suction lift may be too high. Priming can be improved by elevating the suction
and discharge lines higher than the check valves and pouring liquid into the unit through
the suction inlet. When priming at high suction lifts or with long suction lines operate the
pump at maximum cycle rate.