A Quick Guide to Precision Injection Molding

Injection molding is a manufacturing technology that shapes pliable material or plastic using a rigid frame called the mold. Almost all plastic items are produced using precision injection molding, from kitchen appliances, car bodyworks to electronics. It is a popular manufacturing process because it accommodates mass production at a relatively low price.

This technique is used for the mass production of plastic parts with similar features. In precision injection molding, polymer granules are melted and then injected into a mold under intense pressure.

Once in the mold, the injected plastic liquid cools down, solidifies, and hardens to shape. The range of pressure and heat used depends on the use of the end product desired.

Precision injection materials are thermoplastic polymers. This allows the resulting molds to take in color and also be filled with other additives as preferred.

Types of plastic molding

The widely used types of plastic molding are:

  • Blow molding
  • Rotational molding
  • Injection molding
  • Extrusion molding
  • Compression molding
  • Thermoforming

Precision Injection Molding

Common uses of precision injection molding

The injection molding technique is used for manufacturing very high volumes of custom plastics.  For instance, large injection molding machines are used for making car mold parts, while smaller machines are used to manufacture precise plastic components for surgical and medical equipment.

Additionally, there are several types of additives and plastic resins used in the injection molding process. This variety increases flexibility for engineers, manufacturers, and designers.

Injection molds made from aluminum or steel come at an exorbitant price. However, the cost per unit is relatively economical when a consumer needs several similar parts per year.

With precision injection molding, the tooling process up to the end product takes 12-16 weeks for production.

Advantages of precision injection molding

  • High output production

Injection molding allows for mass production of plastics for various uses-Precision molding is a cost-competitive technology for producing high volumes of identical parts.

  • Reliably high productivity

Typically, the precision injection molding cycle takes 15-60 seconds. The duration depends on the size and complexity of the mold part in question. If 3D printing is the preferred model, the process may take up to hours to reproduce parts of similar geometry.

  • Increased repeatability and tolerance

Precision injection molding is highly repetitive while the manufactured parts remain identical. Before a particular mold wears out, it will have been profitably used for production. A typical aluminum mold can survive 5,000 to 10,000 cycles.


  • Appealing visual appearance

A critical strength of precision injection molding is the aesthetics of the end product. The parts can do without extra finishing. The parts can also be polished under extremely high temperatures to create a mirror-like surface.

  • Low scrap waste

Precision injection molding leaves very minimal post-production scrap in relation to traditional processes. Any waste or unused plastic can be re-milled, remolded for recycling.

  • Reduced finishing requirements

Products manufactured using precision injection molding have very minimal post-production work. The items are usually well finished, have a polished appeal upon injection.

Precision injection molding is one of the most common manufacturing processes for providing mass identical plastic products. It is rapidly gaining popularity over the traditional manufacturing processes.

Jayla Jeremy