When the multistage centrifugal pump cracks, it is necessary to take appropriate repair measures according to the depth of the crack, location and whether to withstand pressure. So, multistage centrifugal pump cracks how to do? Don't worry, the following is the multistage centrifugal pump manufacturer Changsha Zoomlian pump industry for your detailed treatment methods and preventive measures, after all, prevention is more important than repair.
1. Crack detection:
Use a hand hammer to tap the pump body, if you hear a hoarse sound, it indicates that there may be cracks.
You can apply kerosene to the suspected crack, then wipe the surface with a cloth, and sprinkle with white powder. If a crack is present, kerosene will penetrate into the crack and wet the white powder, creating a wet line that helps determine the location and length of the crack.
2. crack repair method:
For cracks that do not bear pressure or have low sealing requirements, a circular hole with a diameter of φ3mm can be drilled at both ends of the crack to prevent the crack from continuing to expand.
If the crack appears in the pressure part, it must be repaired. Before repairing welding, it is necessary to clean the oxide, oil and other impurities in the crack area, and select the appropriate electrode for welding according to the size and material of the crack. For example, for gray cast iron shells, cracks can be repaired by cold repair welding or epoxy glass fiber cloth bonding.
3. welding precautions:
In the welding process, the short arc welding technology should be used and hammered after each weld to refine the grain, improve the quality of the weld and reduce stress concentration.
For deeper cracks, it is recommended to use a heterogeneous low-matching electrode for arc welding and heat treatment after welding to eliminate residual stress and prevent re-cracking.
4. Preventive measures:
During the casting process, the solidification of the hot joint can be accelerated by opening the form of tension bar or placing the shaped cold iron at the intersection of the open flange and the thin-walled cavity, so as to reduce the crack defects.
Regularly check and maintain the pump body to avoid cracks caused by mechanical stress or thermal action.
Through the above method, the crack problem of multistage centrifugal pump can be effectively detected and repaired to ensure the normal operation and service life of the pump.