Troubleshoot of centrifugal pump
There are many types of problems happens with a centrifugal pump that is mentioned below.
Centrifugal pump problems
- Flow not develop or low flow
- Low pressure and low head
- Power consumption is high
- High noise in pump
Guide to troubleshoot of centrifugal pump mention below, and we will take a view and try to troubleshoot of centrifugal pump.
Flow not developed or low flow
Troubleshoot guide for flow not developed or low flow in centrifugal pump is mentioned below.
Problem in Instrument
Instrument like (pressure gauge) not working properly check the instrument if any error, replace or correct it.
Cavitation in suction line
Check the NPSHa and NPSHr for investigation of NPSH, check the past history of NPSH and check the impeller chocking.
Pump casing and section line not vented
Pump casing and section line not venting Check the casing and suction line vent properly.
Suction liquid source (tank’s) empty or low level
Suction liquid source (tank’s) could be empty or low level Check the level of your tank and maintain the level of the tank.
Not primed properly
Before run the pump should be primed properly if did not do, stop the pump and do the prime properly.
Flange joints in suction line and pump casing loose
Check flange joint in suction line and pump casing if found loose, tighten the all flange because otherwise due to this, air can sucked with suction liquid and cavitation could occur.
Low pressure and Low discharge head
The reason for low pressure and low discharge head in pump mentioned below.
Check the instrument error and correct it.
Check the cavitation hammer noise happening, check the net positive suction head available and net positive suction head required and past history of NPSH of the pump.
Suction strainer chocked
Open and check the suction strainer, investigate the suction strainer, clean the strainer and box up the strainer.
Impeller rotate in wrong direction
Check the drivers’ direction of rotation and it found wrong then correct it.
Clogged suction line
Check the section line it should be clean from foreign materials like diaries and other, this is also a main reason for low pressure develop.
Warm impeller and wearing
If the impellers or wearing fund worm due to this the clearance between the internal parts has been reduced so flow rate goes down.
Excess the internal parts’ clearance
Due to the increased of internal parts clearance the internal circulation of the fluid goes up so the pressure and head of the pump fall down.
Suction valve and discharge valve throttled
Due to the throttle of suction and discharge valve flow stick restrict at the valve body the head goes down.
Minimum circulation line valve in open condition
Due to the open of the minimum circulation line valves the lines fluid circulation increased through the minimum circulation line so this is also a result of pressure or head rate.
Reduce the number of elbow used, use short angle elbow.
Instrument equipment’s Problems
Check instrument like pressure gauge temperature gauge and others.
Drivers run at high RPM
check the driver drives of rotations and driver RPM.
Driver run wrongs direction
Check the drives on direction of rotation of motors if any problems in correct it.
Cavitation in line due to a leaking from flanges
Check the all flags test leak test fund tight. Impeller may be partially plugged
Cavitation is also reasoned for discharge pressure not building then correct it. Sometimes air aspiration type cavitation is also the main reason.
High power consumption
The reasons and troubleshooting for high power consumption of a pump is mentioned below.
Driver speed is very high
Check the RPM of driver if any found high RPM, correct it.
Liquid viscosity is high
Check the liquid viscosity and install pump as per well-matched with viscosity.
System suction head is lower than as expected
Check the system head npshr of the pumps with the pump designs.
Pump gland seal very tighten
If in the pump gland seals used check the tightness of gland seal and loose the gland and provide proper cooling system.
Access bearing load
Due to the access bearing load also reason for high power consumption, to solve it check the alignment of driver and pump if it is found errors then correct it.
Electrical equipment loose
Check electrical equipment installation in motors and wire connection looseness.
Valve condition in discharge line
Check the valve condition in discharge line if it found throttle, it’s must be fully open. Check coupling bolts and bearing housing of pump and driver.
High noise in pump casing and line
There are one reason for high noise is cavitation.
Prevent the noise of the pump
To prevent the noise of the pump first troubleshoot the cavitation.
All mentioned in link. Other reason for high noise is rotating part rubbing, if needed overhaul the pump and find the rubbed part and correct it. Some times due to the wrong alignment a reason for create noise in pump.
Thanks for read,