News

How to Calculate The Shrinkage Rate of Plastic Molds?

In the intricate world of plastic mold design and manufacturing, every detail is related to the quality and performance of the final product. Among them, shrinkage rate is an important indicator for measuring the dimensional changes of plastic products after being taken out of the mold, and its precise calculation and control are particularly important. Today, we will delve into the calculation formula and method of plastic mold shrinkage rate, as well as how to effectively address this challenge in design to ensure the accuracy of finished product dimensions.

The formula for calculating the shrinkage rate of plastic molds is D=M+MS+MS ², which provides us with an effective tool for quantitatively evaluating the shrinkage rate. Among them, D represents the actual size of the product, M is the mold design size, and MS is the material shrinkage rate. Through this formula, we can anticipate possible dimensional changes in the product during the mold design phase and make corresponding adjustments and compensations.

It is worth noting that accurate measurement of shrinkage rate should follow international standards, such as ASTM D955 method, which provides a scientific and standardized process for determining the shrinkage rate of plastic materials, ensuring the accuracy and reliability of measurement results. 

The shrinkage rate of plastic molds does not exist in isolation, it is influenced by various factors, including plastic variety, molding conditions, mold structure, etc. The shrinkage rate of different polymer materials varies, which requires us to fully understand their physical properties when selecting materials, so that we can make reasonable predictions in the design stage.