Choice of production method
The selected production method affects the choice of plastic material. The production method used to make the product must be established in advance. Not all production methods are suitable for all plastic types and correspondingly, not all plastics are compatible with all production techniques. An appropriate production method saves time and money
The most commonly used plastic processing methods are:
Mechanical machining which refers to processing carried out with various saws and CNC and mechanical machines. In addition, plastics can be glued and welded.
With thermoforming, thermoplastic material is heated to its forming temperature, and the desired shape is then produced with a mould. In this method, the desired shape can be achieved by heating a plastic sheet until it becomes pliable and then bending it or shaping it in a mould.
In vacuum forming, a heated thermoplastic sheet is pressed against the mould by a vacuum. The result is a formed part that reproduces the mould’s shape exactly.
In extrusion, hot plastic is pushed through a shaped sleeve. Pipes and various profiles are produced with this method.
In the calender process, heated plastic is fed through rollers, which press the material into a thin sheet. Products manufactured with this method include coatings, panels and tiles.
In sheet/film extrusion, melted plastic is squeezed through a circular die. Air flow expands the plastic into a thin-walled tube, which can be processed further. This method is used to manufacture plastic bags and films, for example.
In blow moulding, plastic is heated and placed in a mould. Air pressure is then used to push the plastic out to match the mould, resulting in a hollow item, such as a bottle or container.
In rotational moulding, plastic powder or paste is heated inside an enclosed mould. The mould is then rotated until its walls are covered by an even polymer layer. This method is used to produce large hollow items, such as rubbish bins, fuel tanks and various cylinders.
Injection moulding involves heating and mixing the plastic material, which is then injected into a mould at high speed. The method is used to make mobile phone covers, cogs and buckets, for example.
3D printing is used to produce prototypes or one-off items. Powder or filament is used as a raw material in 3D printing. The material is fed to the printer head where it is melted or dissolved in liquid. After this, the printer injects the material on the printing base in layers.
We have prepared a guide in which we compare three production methods:
- Machining or mechanical processing
- Injection moulding
Download our clearly presented guide and expand your knowledge of plastic production methods.
You can download the guide free of charge below or by clicking on this link (in finnish only).