How to select an injection moulding machine according to mould type

Plastic Injection Moulding

The plastic injection moulding is the most widely used method for the manufacturing of thermoplastic parts, approximately 60% of plastic processing machines are injection moulding machines. They can be used to produce parts weighing from a few milligrams to almost 100 kg. In injection moulding plastic injection moulding, intricate and complex shapes can be produced, the limitation is the ability to make a plastic injection mould whose cavity has the same shape as the part; the mould must also allow the part to be ejected. In applications requiring a high production rate and good dimensional control, this process is the most common for thermoplastic polymer forming.

From the point of view of design, one of the main improvements provided by plastic injection moulding is the possibility of incorporating several functions into a single part, so that the number of parts and assembly time can be reduced.

We can say that the most relevant advantages of the manufacture of plastic parts by injection moulding are the following:

• Manufacturing speed; the cooling speed of thermoplastics is almost immediate and consequently production cycles are short, between 10 and 30 sec.
• In general, no finishing processes on the workpiece are necessary.
• It allows the finished product to be obtained in a single step.
• It is a fully automated process.
• The manufacturing conditions are easily reproducible.
• Very complicated parts can be obtained.
• The finished plastic parts are of high quality.

It is important to note that polymers have high coefficients of thermal expansion, and significant shrinkage of the plastic in the mould occurs during cooling. After injection into the mould, some thermoplastics experience shrinkage of close to 10% in volume. Therefore, the dimensions of the injection mould cavity must be larger than those specified on the part in order to compensate for this shrinkage. Translated with www.DeepL.com/Translator (free version)

From Moldblade we offer a wide range of injection moulded plastic parts, such as housings, containers, lids, automotive parts, toys, household appliance parts, tools, rubbish bins, plastic shopping trolleys, plastic cutlery and a large number of everyday items.