How can you calculate cooling time in injection molding?

2 Factors affecting cooling time

The cooling time equation indicates that the cooling time of an injection molded part is dependent on several factors that can be manipulated by the injection molder. These factors include mold geometry, material properties, and processing conditions. Mold geometry affects the value of the constant a and the average wall thickness x, while material properties influence the temperature difference T_d and the heat transfer coefficient h. Processing conditions also determine the temperature difference T_d and the heat transfer coefficient h, as well as how much heat is generated and transferred during the filling stage. To reduce cooling time, mold geometry should be designed to minimize wall thickness variation and avoid thick sections, material properties should be selected to match part requirements, and processing conditions should be optimized for a uniform and rapid cooling of the part.

3 Cooling time optimization

The cooling time optimization is the process of finding the best combination of factors affecting the cooling time to achieve the desired part quality and productivity. This can be done using various methods, such as trial and error, analytical methods, and numerical methods. Trial and error involves testing different values of the factors and observing the results on part quality and cycle time. Analytical methods involve using mathematical formulas or models to calculate the cooling time and part quality based on input values. Numerical methods involve using computer software or simulations to do the same. The cooling time optimization method should be chosen based on data, resources, and expertise, as well as the complexity and specificity of the part and process.