Centrifugal pump maintenance in addition to the normal maintenance procedures and standards should also pay attention to the following points: 1, the concentricity of the pump rotor and volute. Concentricity of the pump rotor and the volute is completely determined by the machining accuracy of the part. The pump rotor and the volute are required to be concentric. The purpose of the pump rotor is to avoid the friction between the moving parts and the stationary part. Second, the concentricity between the two can improve the pump performance and improve the pump efficiency. 2, pump impeller flow channel centerline and volute channel centerline deviation. The lower the impeller runner centerline deviates from the pump housing runner centerline, the higher the pump efficiency. The deviation between the two flow channels should generally not exceed 0.5mm. 3, the bolt tension is appropriate. 4, the pump internal clearance is exceeded, a variety of pump data requirements, see Table 1-1 to Table 1-4. 5, the amount of mechanical seal compression meet the requirements. 6, for high pressure pump shell hydrostatic test when necessary. Table 1-1 Horizontal Split Pumps Clearance of Each Part / mm Diameter of Mating Part Clearance Diameter Interference Max Min Max Min Minimum Case Seal Ring and Housing Impeller and Shaft Bushing and Shaft Gland and Packing Box ID Packing Box and Pump Housing Bearing and Gasket Rear Bearing and Shaft Rear Bearing Outer Diameter and Bearing Box Inner Diameter Rear Bearing Gland and Bearing Box Inner Diameter Front Bearing Outer Diameter and Bearing Box Inner Diameter Front Bearing Gland and Bearing Box Inner Diameter Front Bearing Gland and Bearing Box Inner Diameter Side) Front bearing and shaft Impeller and housing seal ring Water seal ring bore and sleeve outer diameter Water seal ring bore and packing box bore Front gland bore and bearing bore Back gland bore and bearing Outer diameter 0.136 0.094 _ 0.285 0.176 0.123 _ 0.259 0.090 0.060 0.091 0.126 _ 1.66 1.64 0.234 1.64 1.64 0 0.014 _ 0.085 0.062 0.047 _ 0 0.015 _ _ 0.034 _ 1.52 1.14 0.084 1.14 1.14 _ _ 0.068 _ _ _ 0.045 _ _ _ _ _ 0.045 _ _ 0.003 _ _ _0.003 _ _ _ _ _ 0.003 Table 1-2 multi-stage multi-stage centrifugal pump with the Ministry of the gap / mm with the site gap between the front section, the middle section, the back section of the mouth between the radial 0.04 ~ 0.08 anti-rotation between the pump Positioning pin and pump pin hole interference Pump body, between the guide vane anti rotation steering pin and guide pin hole end impeller hub, stop sleeve, balance disc hub axial gap between the balance disc and the balance between the maximum axial clearance gap between the pump and pump seat And pin hole 0.02 to 0.04 1.0 to 1.5 0.3 to 0.5 3 to 5 Top 5, side 0.04 to 0.12 Vertical pin and pin groove between pump and pump base Top 5, unilateral backlash 0.03 to 0.05 Table 1-3 High-speed centrifugal pump parts with the gap / mm Coupling end clearance, mm 2 High-speed shaft and impeller with high-speed shaft and impeller clearance after wear, mm (not more than) Bearing outer diameter and bush with K7 / h6 0.03 H7 / h6 Table 1-4 Deep well pump parts with the gap / mm Conical sleeve with the impeller H7 / js6 Pump seat and motor with H7 / h6 Conical sleeve with the shaft H8 / h6 Pump seat and Suction pipe with H8 / h8 impeller port ring Inner diameter surface and the impeller cylindrical surface with H8 / h8 packing gland and drive shaft clearance 0.75 ~ 1 shell ring outer cylindrical surface and shell cylindrical surface with H7 / k6 _ _
