Casting is a process for the production of plastic film, after the raw materials melting plasticizing extruder. Through T type structure of the forming die extrusion, a flake cast to a smooth spinning cooling roller of the roller surface, diaphragm in the cooling roller by cooling stereotypes, after traction and cutting edge after to winding products.

With a green film blown film extrusion forming tubular membrane, the blank film forming method for sheet. The film is a blank film blowing and drawing cooling stereotypes, and green film cast film is in the cooling roller cooling. In the cast film extrusion casting and cooling process, neither longitudinal stretching, and transverse tensile. Film casting molding, blow film thickness uniformity, good transparency, good sealing performance. Thickness in the range of 0.005-1mm. More commonly used for packaging dry biscuits, melon seeds, made of waterproof material of composite materials such as heat seal material and all kinds of construction.