In the field of model prototype service, injection molding process refers to the process in which molten raw materials are pressurized, injected, cooled and separated to make semi-finished parts of a certain shape.The injection molding process of plastic parts mainly consists of six stages: closing mold -- filling -- pressure maintaining -- cooling -- mold opening -- mold demoulding.

Filling is the first step in the whole process of injection molding after finishing prototype design. The time from the closing of the mold to the filling of the mold cavity is about 95%. Theoretically, the shorter the filling time, the higher the forming efficiency; However, in actual production, molding time (or injection speed) is subject to many conditions.

The role of the pressure-retaining stage is to continuously apply pressure, compacting the melt and increasing the density of the plastic to compensate for the plastic's shrinkage behavior. In the injection molding mold, the design of the cooling system is very important. This is because molding plastic products only cooling solidification to a certain rigidity, after demolding to avoid plastic products due to external forces and deformation.

Demoulding is the last step in an injection molding cycle. Although the products have been cooled forming, but demolding or on the quality of products has a very important impact, demolding mode is not appropriate, may lead to uneven force in demolding products, ejection caused by product deformation and other defects.