How to maintain and service a horizontal multistage centrifugal pump？

Daily maintenance is an important guarantee for the safe and reliable operation of horizontal multi-stage centrifugal pumps. Only when the centrifugal pump runs in good equipment condition can the equipment efficiency be fully utilized to ensure normal production needs.

 

 

• Daily care and maintenance work:

(1) Keep the equipment clean, dry, oil-free and leak-free.

(2) Check the running sound of the centrifugal pump every day to see if there is normal vibration and leakage, and deal with the problem in time.

(3) Check the oil level in the centrifugal pump suspension oil chamber every day to see if it is appropriate. It must be kept at 1/3 and 2/3 of the oil mark.

(4) It is strictly forbidden to operate the centrifugal pump when the liquid in the pool (barrel) is emptied, because the centrifugal pump will not only vibrate violently when it is emptied, but also affect the life of the pump. Therefore, special attention must be paid.

(5) It is strictly forbidden to enter metal objects and flexible materials such as rubber, cotton yarn, and plastic cloth into the centrifugal pump to avoid damaging the flow components of the water pump and blocking the impeller flow channel, so that the pump cannot work normally.

(6) Check the concentricity of the claw coupling regularly.

(7) For centrifugal pumps with packing seals, check the leakage at the stuffing box regularly. The normal leakage at the stuffing box is preferably 10 to 20 drops per minute; otherwise, the packing gland should be adjusted to tighten. It is recommended to use a centrifugal pump with a mechanical seal, such as the KKW series horizontal centrifugal pump.

(8) The bearing temperature should be checked regularly, and its maximum temperature should generally not exceed 70℃~75℃.

(9) In the first month of the operation of the water pump, replace the lubricating oil in the suspension oil chamber after 100 hours of operation. After that, replace the lubricating oil every 500 hours of operation of the water pump.

(10) The support mechanism of the centrifugal pump inlet and outlet pipe system (pipe fittings, valves) should be checked regularly to see if it is loose. Ensure that the support mechanism is firm and the pump body does not bear the support force.

(11) The tightening of the foundation fastening bolts of the centrifugal pump should be checked regularly to ensure that the connection is firm and reliable.

(12) When the centrifugal pump is not used for a long time, the water pump should be disassembled, anti-rusted, reassembled, and properly stored for next use.

(13) When the spare centrifugal pump installed in the production system is not in operation for a long time, it should be rotated 1/4 turn every week to ensure that the pump shaft is evenly subjected to static load and external vibration.

(14) After the centrifugal pump has been running for about 2000 hours, it should be inspected periodically and damaged parts should be repaired or replaced to keep the pump in good condition.

(15) For newly installed or overhauled centrifugal pumps, the motor direction must be tested first before the coupling pin is inserted.

(16) Centrifugal pumps allow the liquid in the pipeline to flow back and reverse the pump when the motor is powered off. However, special attention should be paid to the fact that when the centrifugal pump has a particularly large delivery height difference, a check valve should be installed on the pipeline to prevent backflow of backwater and control the sudden reversal of the centrifugal pump.

 

• Maintenance and care during operation

(1) The water pipeline must be highly sealed.

(2) The pump is prohibited from running for a long time under cavitation conditions.

(3) The motor is prohibited from running for a long time under flow conditions with overcurrent.

(4) Check the pump regularly to see if the motor is running for a long time under overcurrent.

(5) The pump should be supervised by a dedicated person during operation to avoid accidents.

(6) The bearings should be refueled every 500 hours of operation. Motors with power greater than 11KW are equipped with a refueling device, which can be directly injected with a high-pressure oil gun to ensure good bearing lubrication.

(7) After the pump has been running for a long time, if the noise and vibration of the unit increase due to mechanical wear, it should be stopped for inspection. If necessary, the wearing parts and bearings can be replaced. The overhaul period of the unit is generally one year.