After the design of plastic mold, determined the mold structure, to mould parts of the detailed design, which determines the template and the size of the parts, cavity and core size, etc. This will involve the main design parameters such as material shrinkage rate. So only the grasp of forming of plastic shrinkage rate to determine the cavity size of each part. Even if the selected mold structure is correct, but the parameter is undeserved, it is impossible to produce qualified parts.
A, plastic shrinkage and its influencing factors
The characteristics of thermoplastic expansion is heated, the contraction after cooling, of course after pressure will be smaller. In the process of plastic injection forming, injecting molten plastic into the mold cavity, the first end of the filling liquid cooling solidification, ? from the mold