There is rotational molding, compression molding, and blow molding, as well as spray-up molding.


The quality of a plastic injection mould is determined by its geometry and process parameters

Driving Force

The main driving force for polymer melt flow during the filling and compression of the mould is the system pressure (P). P is measured in the holding stage and is related to part geometry and weight. It indicates the quality of the molded part. A system pressure curve is a statistical tool used to predict the quality of injection molded parts.

Proper Injection

A proper injection molding design minimizes the appearance of sink marks and increases the overall strength of the part.


A proper design is also necessary to prevent delamination, where the surface of a part separates from the plastic.



Delamination may be caused by a number of factors, including contaminants present in the plastic or too much reliance on mold release agents.


A good design ensures the flowability of melted plastic. Moreover, a good design reduces short shots and prevents undercuts.

poor designs

However, poor designs may result in short shots. A straight-pull mold is a typical example of a bad mould. A straight-pull mould has 2 halves, and the ribs can be thin or uneven, which increases the chances of short shots.

Good Designer

A good designer can help a company ensure the mould design is right. When designing a product for plastic injection moulding, a critical factor to consider is the wall thickness of the product.

Plastic Injection

The quality of plastic injection moulds can influence manufacturing speed, unit cost, and productivity. If the product is too thick or too thin, it may experience shrinkage or warping.

During layup

During layup, workers manipulate flat sheets of composite material into the desired shape. While hand lay-up is not a high-tech process, it is an important step in the manufacturing process.

market worldwide

Injection molded plastics are a rapidly growing market worldwide. Demand for these products is mainly driven by the packaging industry and the electronic industry. The products produced using these materials are cheaper than their counterparts made from metal.

Furthermore, they are also suitable for many industries and applications. The forecast period for this industry shows an upward growth rate of over 4%, which is expected to spur growth.
This is possible due to the fact that the Chinese government artificially pegs the renminbi currency unit. This policy helps Chinese moldmakers compete for the manufacturing business of North American firms.

Increasing Spending

Increasing spending on construction and manufacturing will further drive the demand for these products. In China, molds are manufactured at extremely low costs. The wages of Chinese moldmakers are much lower than in the North American markets.

Basic Injection Mold

In France, for example, a basic injection mold can cost between 5000 and ten thousand euros. It can accommodate up to 12 parts.