Common faults
Reason&The Solution
Multistage centrifugal pump is not out of the water
1.Startup injection pump enough water(using a vacuum pump, it is no enough)
2.Turn to right
3.Bottom valve does not open or blocked
4.Pump suction height is too high
5.Inlet pipe or leak at the instrument connection
6.Stuffing box parts air leakage
7. Impeller passage was blocked
8. Pump speed is not enough
1.Water injection at least submerged impeller, the best full of pump cavity(the same time when the vacuum)
2. Replace the motor wiring
3.Check the bottom valve, clearing maintenance or updates
4.Reduce the installation height of pump
5. Tighten or blocked air leakage
6. Check the shaft sleeve and sleeve nut, flat linen padded
7.Clean the impeller
8.Check the motor, maintenance or updates
Insufficient flow or no flow(capacity not enough or not out of the water)
1. The water channels blocked
2. Clearance between impeller and seal ring reveal too much
3. Speed did bot reach the specified value
1. In turn, check in and out of the water was clear, eliminate blockages
2.Check or replace impeller and sealing ring
3.Check whether the voltage is too low check whether the motor is bad, motor and adjust the voltage
Multistage centrifugal pump power consumption is too large, motor traffic more than rating
1.Too tightly on the packing
2. Pump rotor and stator rubbing
3.Traffic over the scope of use
4. Inside the pump clearance is too large, the pump efficiency is lower
1.The loose packing
2.Check rotor and stator friction parts
3.The prescribed flow range using pumps
4.Strip inspection and replacement has wear parts
Multistage centrifugal pump abnormal noise and vibration
1.The cavitation
2. Parts loose or fall off
3. The rotor imbalance
4. Shaft bending
5. Pump shaft and motor shaft is different
6.Weak basis
7.Bearing wear
8.Inside the pump clearance is too large
1.Water reduce water pump installation height, simply, reduce line losses
2.Stop inspection, fastening parts
3.The rotor dynamic balance test, turning don’t balance weight
4.Straightening the main pump shaft
5.Adjust the spindle, concentric
6.Reinforce the foundation
7.Replace the bearing
8.Strip inspection and replacement has wear parts
Bearing overheating
1.Bad lubrication
2. Shaft bending
3.Bearing damage
4.Pump shaft and motor shaft is different
5.Instufficient cooling water or without water
1.Refuel(check the oil ring, rotating)
2.Straightening the spindle
3.Replace the bearing
4.Adjust unit, and make it work
5.Check the cooling water
