Inspection of the concentricity of the pump rotor (shaft and rotating parts),Check the concentricity of the shaft of the water pump separately under the conditions of no load and under load. During the assembly of the multistage pump rotor components.
A spacer is placed between the first stage impeller and the balance drum, and a bushing of appropriate length is used to replace the support bearing. Do not tighten the bearing locknut while positioning the bearing. Under the condition of no load, support the shaft on the supporting surface (V-type iron/drum), and the measurement points are: the clearance at the diameter of the impeller, the drum of the impeller, the shaft sleeve, the balance drum, and the shaft end at the coupling. The allowable clearance is 0.05mm.
| Working speed | ≤ 3000 r/min | 3000＜n≤5000 | ＞5000 |
| Maximum allowable radial runout | 0.05 | 0.04 | 0.03 |
If the concentricity check of the water pump rotor part is satisfactory under non-load conditions, fix the rotor part on the shaft by tightening the lock nut. In the same position, check the concentricity of the water pump rotor again. If the radial runout of the rotor exceeds the allowable value at this time, the shaft shoulder, impeller hub, balance drum, and shaft sleeve must be carefully checked if the vertical plane of the shaft centerline is the plane that transmits the axial force.
Rotate the mandrel (if the mandrel is not fixed), reduce the grinding amount as much as possible at the length of the hub and the sleeve, and then check the coaxiality at the outer diameter of the shaft (shoulder, balance drum, sleeve, etc.). , the maximum allowable deviation does not exceed 0.01 mm. If this value is exceeded, it must be reworked.
Re-check the coaxiality of the water pump rotor as described above until a satisfactory test result is obtained, then remove the special tools used for checking and trimming the coaxiality, and then disassemble the rotor parts, and the disassembly process must be carried out in sequence The sequence is marked on the impeller in preparation for the subsequent assembly of the impeller in the same sequence during the assembly of the pump. Special equipment for checking concentricity can be provided by the pump manufacturer upon request.
