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　　Sheet metal work is a kind of work developed in the early 1990s. Its predecessor is cold work. Now we are generally classified as follows: thick sheet metal: 3 mm thick sheet metal forming processing, because of thickness reasons, this kind of sheet metal can not be processed on CNC machinery and equipment, usually using wire cutting, gas cutting, laser cutting and other ways. Examples of manufacturers: shipbuilding, boiler manufacturing and other manufacturing enterprises.

　　Those who engage in such work may be called cold workers. Thin sheet metal: generally refers to the processing of sheet metal below 2mm, through numerical control cutting, punching and folding; through the way of hydraulic forming, through die stamping and cutting, this kind of sheet metal can be called thin sheet metal. Examples of manufacturers: electrical appliances, computer shell manufacturing enterprises, automobile shell manufacturing enterprises, etc. Medium plate processing: between thin plate and thick plate processing, all kinds of processing methods can be adopted. These two kinds of structural fabrication assembly members can be called sheet metalworking. The origin of sheet metalworking is a kind of structure assembling work with the development of sheet metal structure manufacturing, the development of computer technology and the popularization of NC automation equipment. He needs to master the skills, mainly: mechanical structure mapping ability, mechanical structure decomposition ability, sheet metal unfolding calculation ability, general welding, argon arc welding, CO2 protection welding ability, and shift ability.