塑料件的成形收缩率在不同结构的模具上一般是不同的。即使在同一模具成形的同一个零件中,不同方向和部位上的成形收缩率也不相同。在设计塑料模具时一般仅凭经验取收缩率的数值。要得到精确尺寸的塑料制件,重要的是确定成形工艺,然后按制订的工艺条件成形制件。如果制件尺寸与图纸要 Plastic parts of the mold shrinkage in different structures of the mold is generally different. Even in the same mold forming the same part, different directions and parts of the forming shrinkage rate is not the same. In the design of plastic mold generally only experience the value of shrinkage. To get the exact size of plastic parts, it is important to determine the forming process, and then shape the workpiece according to the process conditions. If the size of parts and drawings to