The self-priming pump is characterized by simple and reliable structure and durability. 自吸泵 能工作的正常情况下，一般不需要经常拆开保养，当发现故障后及时排除障后就可以了。 Under normal circumstances that the self-priming pump can work, it is generally not necessary to take apart and maintain it often. When a fault is found, it can be removed in time.
1. Several main parts should be paid attention to when maintaining the pump
A. Rolling bearings: After the oil pump has been running for a long time, the bearings must be replaced when they wear to a certain extent;
B. Front sealing ring and rear sealing ring: When the sealing ring is worn to a certain extent, it must be replaced;
C. Mechanical seal: Generally, the mechanical seal should not be disassembled and inspected without oil leakage. If there is a serious leak at the leak at the lower end of the bearing body, the mechanical seal should be disassembled and inspected. When assembling and disassembling the mechanical seal, you must handle it gently, pay attention to the cleanness of the mating surface, protect the mirror surface of the static ring and the moving ring, and do not knock or collide. Leakage due to mechanical seals is mainly caused by friction on the mirror surface. The repair method can grind the frictional end surface to restore the mirror surface. Another reason for the mechanical seal to leak is that the "o" shaped rubber seal (or cushion) is improperly installed or deformed and aged. In this case, you need to adjust or replace the "O" seal for reassembly.
2. Oil pump disassembly sequence
A. Remove the motor or disconnect the coupling;
B. Remove the bearing body assembly, check the radial clearance between the impeller and the front ring, and check whether the impeller nut is loose;
C. Remove the impeller nut, pull out the impeller, and check the radial clearance between the impeller and the rear seal ring;
D. Loosen the set screw of the mechanical seal, pull out the moving ring part of the mechanical seal, check the fit of the end faces of the dynamic and static rings, and check the seal of the "o" -shaped seal ring (or cushion pad);
E. Unscrew the set nut of the coupling and pull out the coupling;
F. Remove the bearing end cap and remove the pump shaft and bearing;
G. Just assemble in reverse order during installation.
This article label: Self-priming pump
Source: Mixed Flow Pump http://cdmbs.com