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- 8 -
Maintain the specific gravity as per specifications. Review the
specifications.
Control the amount of flow with valves as per specifications.
Improper pulley (coupling) alignment
Change in liquid viscosity
Change in liquid specific gravity
Total pump head too small or too large
Undertensioned drive belt
Align the pulley (coupling).
Overdischarge
Overhaul the suction pipe and eliminate the cause.
Overhaul the discharge pipe and eliminate the cause.
Change the air suction position to prevent air from being sucked.
Blocked suction pipe (including freezing)
Sucking air
Review the specifications with consideration given to the total
head.
Maintain the voscosity as per specifications. Review the
specifications.
Loose bolts and nuts
Blocked discharge pipe (including
freezing)
Air trapped along the suction pipe
Insufficient NPSH
Adjust the drive belt tension.
Improve the suction pipe.
Check the water level, liquuid temperature, and suction piping
resistance in the suction tank and maintain sufficient NPSH.
Tighten the bolts and nuts.
Blocked pump (including freezing)
Abnormal noise is
generated.
Contact your dealer for repair.
Problems
The discharge rate is low.
The discharge pressure is
low.
Causes
Electric motor failure
Overhaul the pump and eliminate the cause.
Main causes
Underdischarge
Control the amount of flow with valves as per specifications.
Pumping water is
inefficient.
Wear of the impeller
Replace the impeller.
The pump generates
excessive heat.
Abnormal vibration is
generated.
The electric motor is
overloaded.
Remedies
The oil in the machine
chamber is contaminated
or decreases quickly.
Wear of the volute liner and lining parts
Replace the volute liner and lining parts.
Wear and tear of the bearings
Replace the bearings.
Wear and tear of the mechanical seals
Replace the mechanical seals.
Wear of the sleeve
Replace the sleeve.
Contact with the impeller
Replace necessary parts.
Too much oil
Put in the proper amount of oil.
Too little oil
Put in the proper amount of oil.
Pump troubleshooting (during operation)