The project adopts Europe's advanced vacuum casting technology and epoxy resin vacuum perfusion, which prolongs the transformer's service life and significantly improves the performance of short-circuit resistance. The product has the characteristics of low voltage between layers, small transverse magnetic leakage, good heat dissipation, small volume, strong overload capacity and small noise, etc. It has the characteristics of safe use, strong environmental adaptability, convenient installation and maintenance, no pollution, low operating cost, good insulation performance and so on. It is the main product of domestic dry type transformer. But the transformer produced by the noise, poor heat dissipation and other shortcomings, different from other similar products, we hope to get the help of experts. Ultrasonic finishing equipment for metal parts (hereinafter referred to as finishing equipment for metal parts) is a kind of equipment that realizes plastic processing of metal parts surface by combining ultrasonic wave and machine tool. By finishing, the surface stress field of parts can be changed to produce compressive stress in the low pressure casting machine on the surface of parts, so as to improve the fatigue life and stress corrosion resistance ability of parts. The developed equipment still has some technical problems: 1. The surface roughness value cannot reach below RA0.1, and the surface microhardness is improved between 20%-50%. In addition to reducing the surface roughness of the workpiece, the comprehensive physical properties of the metal surface quality should be improved. At present, there is a big gap between China's bevel gear milling machine industry and foreign countries. Some high-end products are made by China's casting equipment on the surface, and the core technology is actually from foreign countries. The processing equipment of small spiral bevel gear manufacturing enterprises in China is mainly mechanical rotary milling machine. These enterprises all want to expand. In view of the market situation, I want to produce mechanical rotary milling machine and also want to develop CNC milling machine to improve our competitiveness in this field.