When the marine centrifugal pump is disassembled and overhauled, some important parts should be marked before disassembly and assembly, especially for some large and complex bilge pumps. The dismantled parts must be boxed and kept properly. The joint surface should be strictly protected from bruises. When assembling, the coordination clearance of each movement should be strictly checked. When it is difficult to disassemble and assemble, do not forcibly beat it. You should carefully find out the cause and remove the fault before disassembling and assembling. In order to ensure the quality, still need to pay attention to the following points:

1. Before the pump is assembled, the rotor part should be pre-installed first, and the coaxiality of the impeller, shaft sleeve and balance disc with the shaft can be checked one by one with a dial indicator. The coaxiality of the shaft sleeve should be ≤0.1mm, the coaxiality of the balance disc should be ≤0.06mm, and the coaxiality of the outer diameter of the impeller and the side of the water blocking ring should be less than 0.08~0.14mm.

2. When assembling the guide wheel centrifugal pumps, make sure that the impellers are aligned with the guide wheel mouth one by one. When the deviation between the two is not large, it can be adjusted by adding a washer between the distance sleeves (stop sleeves), but if the deviation is large, then a suitable stop sleeve should be replaced.

3. The shaft alignment of the pump and the motor should be done carefully. After alignment, the axial distance between the two coupling joints is generally 2~4mm for small and medium-sized centrifugal pumps, 4~5mm for medium-sized pumps, and 4~8mm for large-scale pumps.

4. The base of the centrifugal pump must have sufficient rigidity to prevent vibration during operation. The pump body must be firmly connected to the base, and the fewer pads on each contact point the better to increase rigidity.