How to overhaul the components of a centrifugal pump

1. Centrifugal oil pump pump head, pump housing and guide impeller 1. Clean and inspect the impeller at all levels, and there should be no defects such as wear, cracks, erosion, etc.

2. The anti-rotation pin of the centrifugal pump guide vane should be free from bending, breaking and loosening. The surface of pump head and pump casing sealing ring shall be free of pits, scars and grooves. The maximum allowable surface roughness Ra shall be 0.8 μm. The assembly gap between the sealing ring and the pump head and centrifugal pump casing shall be 0.05 to 0.10 mm. The ring should not be loose.

3. Take the centrifugal oil pump pump head and centrifugal oil pump pump shell as the benchmark, measure the radial circular runout of the inner ring of the seal ring, whose value is not more than 0.50 mm, and the end surface runout should not be greater than 0.04 mm.

4. Measure the amount of clearance between the pump head of the centrifugal pump, the seal ring of the pump housing, and the assembly seal ring. The value should be between 0.50 and 0.60 mm.

Second, the centrifugal pump impeller, cleaning and inspection of the impeller surface at all levels, the impeller surface should be no cracks, wear and other defects, the impeller runner surface should be smooth, and no scaling, burrs, the blade should be no cracks, erosion and thinning defects.

2. Check the sealing ring of the inlet and outlet of the impeller at each level. There should be no looseness. The surface of the sealing ring should be smooth and free of burrs. The maximum allowable surface roughness, Ra, is 0.8μm, and the assembly clearance with the impeller should be 0.05 to 0.10 mm. Based on the inner bore of the impeller, check that the radial runout of the impeller should not exceed 0.05 mm. Face runout is not more than 0.04 mm.

3, the impeller and shaft use interference fit, generally H7/h6. The interference between the key and the keyway is 0.09~0.12 mm. After assembly, the clearance at the top of the centrifugal oil pump key is 0.04~0.07 mm.

4, the impeller must be statically balanced.

Third, the centrifugal pump throttle seal 1, cleaning and inspection of the throttle seal surface, there should be no cracks, eccentric wear and other defects, the maximum allowable surface roughness Ra is 0.8μm;

2. Centrifugal pump throttle seal and pump body adopt H7/p6 cooperation. The outer circle is used as a benchmark to measure the radial runout of the inner hole. The value should not exceed 0.02mm.

3. Measure the clearance between the throttle seal and the pump shaft of the centrifugal oil pump. The value should be between 0.25~0.30 mm.

Fourth, centrifugal pump shaft, cleaning and check the pump shaft, the pump shaft should be no cracks, serious wear and other defects. If there has been wear, cracks, erosion, etc., should be recorded in detail and analyze the reasons.

2. To test the straightness of the pump shaft of the centrifugal pump, the value should not exceed 0.05mm in the whole length. The surface of the journal must not have pits, grooves, etc. The maximum allowable surface roughness is 0.8 μm, and the roundness and cylindricity of the journal should be less than 0.02 mm.

3, centrifugal oil pump keyway centerline axis centerline parallelism error should be less than 0.03mm/100.