Principle of high-pressure injection moulding

The following rules are some of the basic ones and are not sufficient to optimize the design, 

These rules can be modified according to the actual problems. 

High thickness favours sinking, warpage and shrinkage, porosity and voids. Designing ribs or gussets can reduce wall thickness. 

Injection moulding leads to the best part tolerances but plastics differ because of their morphology, structure, rheology, etc. The geometry of a part and the complexity of the corresponding mould vary. Consequently, the tolerances of a part depend on  

Telecommunications, the watch industry, medical applications, and the automotive and chemical industries are asking for smaller and smaller parts and components made of plastic. Standard injection machines are unsuitable for micro-parts. Here we describe, without claiming to be ejdiaustive, two examples of special machinery developed by Battenfeld and Medical Murray. 

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Figure 5.2. Principle of high-pressure injection moulding...

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