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CHEMFLO 6 (en)
PN MPCF6-IOM
PROBLEM
PROBABLE CAUSE
REMEDY
Pump is noisy or vibrates.
1. Improper pump/driver alignment.
1. Align shafts.
2. Partly clogged impeller causing
imbalance.
2. Back-flush pump to clean impeller.
3. Broken or bent impeller or shaft.
3. Replace as required.
4. Foundation not rigid.
4. Tighten bolts of pump and motor or
adjust stilts
5. Worn bearings.
5. Replace.
6. Suction or discharge piping not
anchored or properly supported.
6. Anchor per Hydraulic Institute Stan-
dards Manual recommendation.
7. Pump is cavitating.
7. Check NPSHa, Air leaks to ensure that
there is enough liquid for pump opera-
tion.
Excessive leakage from stuffing box/seal
chamber.
1. Worn mechanical seals.
1. Replace worn parts.
2. Overheating mechanical seal.
2. Check lubrication and cooling lines.
3. Shaft sleeve scored.
3. Remachine or replace as required
Motor requires excessive power.
1. Head lower than rating; pumps too
much liquid.
1. Consult factory. Install throttle valve,
trim impeller diameter.
2. Speed is too high.
2. Electric motor wiring is wrong.
Replace motor.
3. Wrong direction of rotation.
3. Check wiring diagram.
4. Impeller is clogged.
4. Back flush pump to clean impeller.
5. Impeller is binding.
5. Relieve strain on casing; adjust impel-
ler clearance.
6. Driver and pump are misaligned.
6. Realign driver with pump.
7. Power frame shaft is bent.
7. Repalace shaft.
8. Worn suction side plate or wear rings.
8. Replace defective parts as required.
9. Liquid heavier than expected.
9. Check specific gravity and viscosity.
10. Stuffing box too tight.
10. Readjust packing. Replace if worn.
11. Rotating parts bind.
11. Check internal wearing parts for
proper clearances
Pump fails to prime or loses its prime.
1. Air leaks in suction line.
1. Clean and tighten all suction connec-
tions; relocate suction inlet in liquid
source.
2. Suction strainer is clogged. Suction
lift is too high.
2. Clean debris from strainer. Re-eval-
uate pump requirements and correct
suction conditions.
3. Defective priming valve.
3. Replace valve.
4. Defective seal.
4. Replace seal.
Insufficient pressure.
1. Excessive air in liquid.
1. Clean and tighten all suction connec-
tions; relocate suction inlet in liquid
source.
2. Driver is not operating at rated speed. 2. Check electric motor voltage; check
engine rpm
3. Wrong direction of rotation.
3. Change rotation to concur with direc-
tion indicated on bearing housing or
pump casing.
4. Total head is too high.
4. Re-evaluate head conditions.
5. Worn suction side plate or wear rings.
5. Replace defective parts as required.
6. Broken or bent impeller or shaft.
6. Replace as required.
7. Air leak through gasket.
7. Replace gasket.
8. Liquid is vaporizing
8. Provide additional pressure on liq-
uid being pumped by elevating liquid
source. Check temperature of liquid
being pumped’
RELEASED 03/Sep/2021 12:38:55 GMT
