Metal Packaging Can Manufacturing Process

The traditional production method of metal packaging cans is to first cut the iron sheet flat blank into long blocks, then roll the blank into a cylinder (i.e. cylinder body), and then solder the formed longitudinal joint line to form a side seal. One end of the cylinder (i.e. tank bottom) and the circular end cover are mechanically formed into a flange and rolled to seal (i.e. double rolled edge joint), thereby forming the tank body; Seal the lid on the other end after loading the product. Due to the fact that the container is composed of three parts: the bottom, body, and lid, it is called a three piece can. This can making method has remained largely unchanged for over 150 years, with only significant improvements in automation and processing accuracy. In recent years, the welding seam of the side seal has been changed to fusion welding.

In the early 1970s, a new principle of can making emerged. According to this principle, the can body and bottom are a whole, formed by stamping a circular flat blank, and sealed after being loaded into the product, which is called a two piece can. There are two forming methods for this type of tank: stamping thinning stretching method (i.e. punching drawing method) and stamping re stamping method (i.e. deep drawing method). These technologies themselves are not new. Punching and drawing method has been used to manufacture cartridge cases as early as in World War I. Canmaking is different from using ultra-thin metal and high production speed (annual output can reach hundreds of millions).