Repair of broken shaft of permanent magnet motor

In recent years, permanent magnet motors have become a new product in the mechanical equipment industry. This motor is widely used in various industries because of its advantages such as high power factor, low heat generation, and simple structure.

However, in the process of using permanent magnet motors, the phenomenon of shaft breakage will inevitably occur. For this phenomenon, relevant personnel must take timely repair measures to improve the working efficiency of permanent magnet motors. So how to repair the broken shaft of permanent magnet motor? Let’s discuss it together below!

For the repair of the broken shaft of the permanent magnet motor rotor shaft, there are three main methods to repair it, as follows:

The is to use electric welding to repair the broken shaft; the second is to use the hot sleeve method to repair the broken shaft, and the third is to replace the broken shaft.

1. Use electric welding to repair the cracked shaft

First, we use an oxygen-acetylene flame to groove the fracture and remove the welding slag on the surface. Then we use an electric welding rod to build up welding on the fracture of the shaft until it is slightly larger than the original size, and machine the shaft on a lathe. .

2. Use hot sleeve method to repair broken shaft

First, measure the diameter D of the rotating shaft at the broken point of the rotating shaft. Determine the inner cone size according to the dimensions of D=0.8D and L=1.1D. Then, cut the shaft diameter out of the inner cone according to the calculated size, and use No. 4 according to the calculated size. Make a steel sleeve from steel, use an oxygen-acetylene flame to heat the steel sleeve, and use liquid nitrogen to cool the journal at the same time. Heat the steel sleeve on the journal, wait for the shaft to cool, and then use fine turning to make the outer diameter of the steel sleeve. into a rotating axis.

3. Replacement of broken shaft

First, remove the rotating shaft, and then make a sleeve from a steel pipe so that its inner circle can pass through the rotating shaft and resist the iron core. Put the made sleeve on the rotating shaft and stand it up, hoist it into the hydraulic press, and press out the rotating shaft. Then measure the size of the rotating shaft as required, perform turning of the rotating shaft, and clamp and position the flat-head drilled rotating shaft blank on the lathe.

Roughly carve the shaft extension and each step, leave a machining allowance of 2-3mm for the outer diameter, and leave a machining allowance of 1mm for each step within the shaft for chamfers. Then finely carve the permanent magnet motor's rotating shaft for each step of the shaft extension, and the shaft extension. Leave a machining allowance of 0.3mm for the bearing gear, iron core gear, and other outer diameter dimensions and axial gear dimensions according to the records and matching requirements. Carry out the grinding process and milling process, use clamps and two thimbles for positioning, and check If a deviation is found in the ovality of the rotating shaft, the center hole must be re-grinded, and all steps except the clamp must be ground. Then use the marked rotating shaft to lift it into the flat-nose pliers, align it according to the crosshairs, clamp it, and mill in sequence. The keyway of each step completes the repair of the broken shaft of the permanent magnet motor.