Precautions for Mud Pump Shaft Inspection and Causes of Bearing Heating

Points to note for checking the main shaft of the mud pump

• After the drilling machine is installed at the drilling site, check whether the prime mover and the main shaft of the pump are on the same axis. If they are not, adjust them correctly.

• The inlet and outlet pipelines of the mud pump should have load-bearing support to avoid the pipeline weight acting on the pump body. Without high-pressure clear water protection, the packing chamber components will quickly wear out.

• When the mud pump is working, high-pressure clear water must be injected into the packing chamber to protect the shaft seal components. The high-pressure clear water pump should not be turned off during normal operation.

• The suction head in the performance table of the mud pump refers to the pump's cavitation resistance under normal temperature and clear water conditions. When pumping sludge and sand, the inlet water pressure of the pump should be as positive as possible.

• When replacing vulnerable parts such as impellers and liners, adjust the clearance between the impeller and liner. The axial clearance between the impeller and the liner has a great influence on the performance and service life of the pump.

• Please inject lubricating grease into the bearing part of the mud pump in time. The water pressure should be greater than the working pressure of the mud pump. The installation of the pipeline should extend outward from the pump inlet and outlet flanges and the supporting position should be determined immediately.

• The pump vibrates abnormally during work. When the noise and bearing temperature rise too high, stop the pump immediately for inspection. When mud contains a large amount of solid particles, the flow and head of the pump will also be affected, and the condition of the medium should be considered when selecting the pump.

Why does the bearing of the mud pump heat up?

1. The two ends of the bearing heat up, and noise and vibration occur

Cause of failure: 

• Water enters the bearing: The reason for the water entering the bearing is that the environment in which the mud pump is placed is relatively humid, or the water seal leaks seriously, and water enters the bearing. The solution at this time is to replace the bearing. If it is severe, the entire bearing assembly needs to be replaced.

• The lubrication oil is too much or too little: Excess lubrication oil affects heat dissipation, and too little does not provide good lubrication, so excess or insufficient lubrication oil can cause bearing heating. The solution at this time is to add lubrication oil to the bearing correctly according to the instructions.

• The bearings are not properly assembled: When assembling the bearings, if the gap between the bearings is not adjusted properly, the friction between the bearings will cause the bearings to heat up. Adjusting the gap between the bearings at this time can solve the problem.

2. The driving end heats up

Cause of failure: 

The belt is tightened too much; adjusting the looseness of the belt is appropriate when the belt can be depressed by one finger in the middle.

3. The bearings have abnormal noise and vibration

Cause of failure: 

• Foreign matter enters the bearing : If the water seal leaks severely, the slurry enters the bearing during the splash process, and the friction between the foreign objects in the bearing and the slurry will cause heating and vibration of the bearings. At this time, the bearing needs to be removed and cleaned. If the bearing has worn severely, the bearing needs to be replaced.

• The motor shaft and the pump shaft are not centered, not parallel, or the shaft is bent : At this point, the motor shaft and the mud pump shaft need to be reconnected to ensure that they are centered and parallel.

• The impeller loses balance : After the impeller is used for a period of time, it will have normal wear and tear, which will cause the impeller to be unbalanced. The impeller drives the shaft, which in turn drives the bearing to vibrate and heat up. At this time, the impeller needs to be replaced.

4. The bearings heat up, and the shaft moves. This is caused by bearing damage, and the bearing or bearing assembly needs to be replaced.