Automotive water pump bearing manufacturers explain the repair of pump shafts

Automotive water pump bearing manufacturers explain the repair of pump shafts

    ① Repair of zigzag pump shaft After the zigzag direction and the amount of zigzag of the pump shaft are measured, if the zigzag amount exceeds the allowable scale, the pump shaft can be repaired by straightening. There are two ways to straighten the pump shaft, namely cold straightening method and hot straightening method. The straightening method can be selected according to the amount of tortuosity of the pump shaft. In the straightening, you should not rush to achieve results, and intersperse with the recheck of the pump shaft straightness, so as to obtain a comparatively accurate straightening effect.

    ② Repair of pump shaft wear. For partially worn pump shafts, if the wear depth is not too large, the worn parts can be repaired by surfacing welding. After surfacing, it should be turned to the original scale on a lathe. If the wear depth is large, the repairing method can be used to repair the pump shaft. The repair method is to turn the wear layer of the pump shaft on the lathe first, and then turn a sleeve to make the sleeve and the pump shaft fit together. And make the inner diameter of the sleeve and the outer diameter of the polishing layer on the pump shaft form an interference fit. The interference value can be determined according to the diameter of the pump shaft. Normally, the interference is 0~0.03mm. When the sleeve is installed on the pump shaft, it can be driven in with a sledgehammer or a press. When the interference is large, it can also be installed with the "hot-loading method" to heat the sleeve to make it heated Expand, then install the sleeve on the pump shaft to allow it to cool naturally, and finally, turn the sleeve part of the pump shaft to its original size.

    Regarding pump shafts that are severely worn or cracked, they are generally not repaired and replaced with spare parts.

    ③ Repair of the keyway If the side of the keyway on the pump shaft of the centrifugal pump is slightly damaged, it can be repaired with a file. If there is a serious tilt, it should be repaired by surfacing. When repairing, first use arc welding to build up the prototype of the keyway, and then use milling shoes, planing or manual filing to restore the original size and shape of the keyway.

    In addition, it can also be repaired by changing the keyway position. That is, the original orientation of the keyway is fully surfacing, and then, the curvature radius of the surface is the same as that of the journal by the method of curved surface filing, and the oil-slip connection is formed. Finally, the shaft is rotated through 180° on the back of the original keyway. In the corresponding position, a new keyway is processed according to the original size and shape of the keyway.