The materials of motor shell are generally cast iron, cast aluminum alloy, section steel (steel pipe), steel plate and so on. Low-power motors in China generally use cast iron, cast aluminum alloy and steel (steel pipe) shells, which have a large amount of workpiece processing, many processing procedures and long production cycle. The working environment of operators is poor and the labor intensity is high; Energy waste is great, and materials waste fire.

Internationally, developed countries such as Germany, Belgium, Japan and other countries have adopted a large number of steel shells as early as the middle of this century. This new processing technology of casing is a kind of processing technology with little cutting. Some domestic motor manufacturers began to study the manufacture of steel plate casings in the early 1970s, and a certain batch was formed in the mid-1980s. However, due to the use of cutting machine-pressing "U" type (or "W" type)-pressing "O" type, welding (manual or CO2 shielded welding)-polishing-once turning 1 18 pieces (referred to as bottomless chassis for short), there are many types of equipment used, and the proportion of human factors affecting the quality is large, so it is difficult to guarantee the quality.

At present, some developed countries generally use advanced special processing equipment for processing, which has high mechanization and automation and good quality. In the motor market of developed countries, low-power motors are generally steel plate shell motors. 1989, domestic trial-produced steel casing processing equipment-steel casing winding machine, motor steel casing welding machine and other single machines have been started. In recent years, materials are expensive and the domestic motor market is weak. In order to reduce the manufacturing cost of motor, improve the quality of steel plate shell, enter and occupy the motor market in developed countries, it is necessary to study the new manufacturing technology of motor steel plate shell.