Gardner Denver HD-2250, Operating And Service Manual

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PROBLEM POSSIBLE CAUSE SUGGESTED ACTION
Cavitation, Fluid Knock
1. Improper suction system 1. See recommended system
or Hammer. layout. layout in manual.
2. Low suction pressure. 2. See Low Suction Pressure
problem.
3. Suction stabilizer and 3. Install suction stabilizer
pulsation damper not used. and pulsation damper.
4. Defective stabilizer or 4. Repair and recharge or
damper. replace.
5. High fluid temperature or 5. Reduce pump speed.
viscosity.
6. High fluid vapor pressure. 6. Increase NPSH.
7. High acceleration head. 7. Increase supply line size.
Decrease supply line length.
8. Suction valve spring too stiff. 8. Use weaker spring.
with low NPSH.
9. Air/Gas in pumped fluid. 9. Allow more settling
time in supply tank.
Reduce pump speed.
10. Air entering suction line. 10. Repair suction line.
11. Air entering charging pump. 11. Tighten or replace shaft
packing or seal.
12. Air entering or charge gas 12. Repair and recharge
escaping from suction stabilizer
stabilizer.
13. Multiple pumps operating in 13. Use a suction stabilizer
phase. on each pump. Separate
lines may also be needed.
Suction or Discharge Line
1. Line(s) not supported. 1. Install supports or
Vibration. hangers.
2. Pump cavitating. 2. See Cavitation, Fluid Knock
or Hammer problem.
High Crankcase Oil
1. High ambient temperature. 1. Use an oil heat exchanger
Temperature. with a circulating pump.
2. Improper type/grade oil used. 2. Use recommended oil.
3. Pump overloaded. 3. Reduce pump speed and/or
pressure.
4. Improper clearance in main 4. Check and adjust clearance.
or rod bearings, crossheads Replace parts as required.
or bushings.