According to the scope of the application of plastic can be divided into the following 3 categories:1, general plastics 2, engineering plastics 3, special plastic 　

Polyoxymethylene is a kind of linear polymer with high density and high crystallinity. It has a high crystal structure in solid state.　

Forming process of Polyoxymethylene:1, pre drying 2, barrel temperature 3, injection pressure and injection speed 4, forming cycle 5, mold temperature 6, after treatment　

Foam polystyrene foam method:1, steam blowing 2, hydraulic press direct steam foaming 　

Compared with the cavity mold, the single cavity mold has the following advantages:1, plastic parts of the shape and size are always consistent 2, process parameters are easy to control 3, the structure of the mold is simple and compact, the design of freedom