The shaft of the split case pump is a very important part, and the impeller rotates at high speed through the motor and the coupling. The liquid between the blades is pushed by the blades, and is continuously thrown from the inside to the periphery under the action of the centrifugal force. A low pressure zone is formed when the liquid in the pump is thrown from the impeller to the edge. Because the pressure of the liquid before entering the pump is greater than the pressure of the suction port of the pump, the position where the pressure difference is discharged from the liquid, the split case pump must be regularly planned according to the management experience and equipment condition of the production equipment, and the maintenance should be carried out according to the plan.

1. Ra=1.6um on the surface of the bushing.

2. The shaft and bushing are H7/h6.

3. The shaft surface is smooth, without cracks, wear, etc.

4. The parallelism error between the centerline of the keyway of the centrifugal pump and the centerline of the shaft should be less than 0.03 mm.

5. The allowable bending of the shaft diameter is not more than 0.013mm, the middle part of the low-speed pump shaft is not more than 0.07mm, and the middle part of the high-speed pump shaft is not more than 0.04mm.

6. Clean and check the pump shaft of the double-suction mid-opening pump. The pump shaft should be free of defects such as cracks and serious wear. There are wear, cracks, erosion, etc., which should be recorded in detail, and the reasons should be analyzed.

7. The straightness of the shaft of the centrifugal oil pump should not exceed 0.05 mm over the entire length. The journal surface shall be free from pits, grooves and other defects. The value of the surface roughness is 0.8μm, and the roundness and cylindricity errors of the journal should be less than 0.02mm.