1. Maintenance method and quality standard of IS series clean water centrifugal pump, IR hot water pump, IY single stage oil pump, IH chemical pump and other series single stage single suction centrifugal pump
The pump body and base should have no cracks, and the casting surface of the vortex chamber and liquid channel inner wall of the pump body should be smooth. When cracks or other casting defects that can be welded are found in parts not under pressure, repair them according to JB/TQ369 "Welding Repair of Cast Iron Parts for Pump".
Double suction impeller centrifugal pump body and pump cover in the plane, with a meter long ruler inspection should not exceed 0.1mm, assembly pad with 0.2~0.25mm paper pad.
2, pump body installation of levelness:
a. Single suction centrifugal pump: longitudinal (along the pump shaft direction)0.05mm/m; Transverse (perpendicular to the pump shaft)0.10mm/m.
b. Double suction centrifugal pump: longitudinal and transverse 0.05m/m.
3, single stage centrifugal pump shaft and sleeve
1) The pump shaft should not have corrosion, crack and other defects, repair or replace the pump shaft when necessary can be nondestructive testing, detection of cracks.
2) The surface roughness of the pump shaft journal: 3.2 where the impeller, sleeve and coupling are installed, 1.6 where the rolling bearing is assembled, and 0.8 where the sliding bearing is assembled
3) Take the journal at the two bearings as the fulcrum, and check the radial circular runout of the journal at the parts of the assembly impeller, shaft sleeve and coupling with the micrometer, which should be no more than 0.03mm.
4) The offset of the keyway center to the center line of the journal shall be no more than 0.06mm, and the skew shall be no more than 0.03mm / 100mm.
5) After the keyway is worn, it can be appropriately increased according to the wear condition, but the maximum size can only be increased by one level according to the standard size. When the structure and force permit, another keyway can be opened in the direction of 900 or 1200 of the original keyway.
6) After the wear of the journal, it can be repaired by electroplating, spraying or coating.
7) The shaft sleeve material shall conform to the drawing; The shaft sleeve is not allowed to crack, the surface of the outer circle is not allowed to have trachoma, porosity, loose and other casting defects.
8) H8 / h8 or H9 / h9 shall be used for the coordination of shaft sleeve and shaft.
4, single stage centrifugal pump impeller
1) The surface of the impeller of the centrifugal pump and the inner wall of the liquid flow channel should be cleaned clean, without sticky sand, burr and dirt; The connection between the processed surface and the non-processed surface at the inlet of the flow channel should be smooth.
2) Impeller and shaft generally adopt H7 / h6 coordination.
3) The newly installed centrifugal pump impeller must be static balanced, and the unbalance weight of static balance should not be greater than the value in Table 6; When using the method of removing the weight from both sides of the impeller, the thickness of the blade should not exceed 1/3 of the original wall thickness, and the cutting part should be smoothly connected with the uncut part.