| HXN5 is high power diesel locomotive introduced from the General electric company of the U.S. CSR Chengdu Co., Ltd introduced four types of electrical motors which are the supportive products of the HXN5. When CSR Chengdu converts the process of the manufacture techniques, It is found that the magnetic windings’ inter-turn insulation of Alternator is frequently breakdown when its insulating property is tested, that the first-pass qualified rate is only 70% and large amounts of rework and cost are wasted, also the production progress and the fulfillment rate of market orders are heavily restricted. In the paper, through analyzing and investigating the performance of inter-turn insulation and the feasibility of manufacturing process, It is found the reason that first-pass rate is so low coming from the burrs and dregs which existed the between of the coils, and there is a big space in improving the processes of manufacture technique. But for burrs, edges and other impurities, it is figured out that the cleanness of work environment, the identifiers of work progress, the polishing sequence and quality all play an important role on the cleanness between coils. Therefore, oil pikes are used to mark the obverse side when coils are being twisted, the polishing is only for local parts instead of the whole one, and alcohol is used to scrub but not using high-pressure wind to blow. By using these methods, the burrs are reduced in the intermediate process, the environment pollution is avoided and the cleanliness in the field is further improved, and the insulation qualification between coils is guaranteed. Through the improvements, the pass percent of the magnetic windings is greatly promoted from 70% to 93%. Ultimately, the process flows of the home-made products are optimized and solidified, and the whole copy of foreign techniques and products is broken, which creates good conditions and sets up solid basis for ensuring electrical motor quality, reducing the cost of material consumption and promoting market competitiveness. |
