Knowledge Set for Plastic Mold Design

Plastic mold design plays a very important role in injection molding production, so what are the key knowledge points of plastic mold design? Do you need to pay attention to the requirements as a qualified designer?
1、 Design basis
The accuracy of dimensions and the correctness of their related dimensions.
Based on the specific requirements and functions of the entire product of plastic products, determine which type of external quality and specific size they belong to:
Plastic products with high requirements for appearance quality and low requirements for dimensional accuracy, such as toys;
Functional plastic products with strict size requirements;
Plastic products with strict requirements for appearance and size, such as cameras.
Is the demolding slope reasonable.
The demolding angle directly affects the demolding and quality of plastic products, which is related to whether the injection process can proceed smoothly:
The demolding slope is sufficient;
The slope should be compatible with the parting or parting surface of the plastic product during molding; Will it affect the accuracy of appearance and wall thickness dimensions;
Will it affect the strength of a certain part of the plastic product.
2、 Design Program
Analysis and digestion of plastic product drawings and solid samples:
A. The geometric shape of the product;
B. Dimensions, tolerances, and design criteria;
C. Technical requirements;
D. Plastic name and grade
E. Surface requirements
Number and arrangement of cavities:
A. The weight of the product and the injection volume of the injection machine;
B. The projected area of the product and the locking force of the injection machine;
C. The external dimensions of the mold and the effective area of the injection machine installation mold, (or the distance between the injection machine pull rods)
D. Product accuracy and color;
E. Whether the product has a side shaft core and its processing method;
F. The production batch of the product;
G. Economic benefits (production value per mold)
After determining the number of cavities, the arrangement of cavities, namely the arrangement of cavity positions, involves mold size, design of pouring system, balance of pouring system, design of core pulling (slider) mechanism, design of inserts and cores, and design of heat exchange system. These issues are related to the selection of parting surface and gate position, so necessary adjustments should be made during the specific design process, To achieve a more perfect design.