The application history of three-piece cans has been nearly 200 years. Although it has been improved many times, its basic composition is still made of three metal sheets (mostly tinplate) of can body, bottom and lid, with the name “three-piece can” . The shape, size and manufacturing method of the bottom and lid of the ordinary three-piece can are exactly the same, and they are collectively called the lid. There are two main sealing forms for the can body: soldering and welding. The former was used earlier, but due to the lead in the solder, it has been eliminated; the latter can avoid lead pollution, low energy consumption, and low material consumption , but the production equipment is complicated.
Three-piece cans have good characteristic, can produce cans of various shapes, high material utilization, easy to change size, mature production technology, and many types of packaging products.