Many of the products we use daily wouldn’t exist without the essential process of injection moulding. We put this clever process to work every day in our reinforcing solutions for the Australian construction industry. So, how does injection moulding work? Let’s sort through the basics.

What is Injection Moulding?

Firstly, let’s look at what injection moulding actually is. Think of it like this: we take plastic pellets, heat them until they melt into a thick liquid, then inject that liquid into a mould shaped like the product we want to create.

The plastic cools, hardens and out comes the finished product. Dead simple in concept, but brilliant for churning out thousands of identical parts with accuracy. While we mostly use plastics, some clever sparkies and other manufacturers set up injection moulding with certain metals and glass thanks to specialised equipment.

How Does Injection Moulding Work?

The process isn’t rocket science, but it is clever. First, you need the mould itself. These moulds are made from metal such as aluminium or steel, and precision machined to a very specific size and shape. The mould is typically the most expensive element of injection moulding and once you have this, your machine can produce thousands of items per hour.

Once you have your mould, you take plastic granules or other materials and feed them into a heated barrel. The heat melts these granules into a liquid. Then, a screw pushes this molten plastic through a nozzle and injects it into the mould cavity. The mould is clamped tight under serious pressure while the plastic cools and hardens into the set shape. Finally, the mould opens with the finished product.

Benefits of Injection Moulding

This manufacturing method is so popular because it’s:

Quick: Once you’re set up, parts are created at an impressive speed.
Consistent: Every part is essentially a carbon copy of the last.
Versatile: You can create complex shapes that would be impossible with other methods.
Compatible: Works with all sorts of different materials and product outputs.
Economical: Setting up can be costly, but once operational, is cost effective.
Environmentally friendly: Less wastage, plus leftover material can usually be recycled.
Tough: The parts are durable and built to withstand heavy use.

When Is Injection Moulding Used?

Injection moulding is a widely used manufacturing method today. It’s especially effective when you’re seeking:

A large volume of identical parts
Complex shapes that need to be exactly the same every time.
Precision as a non-negotiable.
To keep material waste to a minimum.
To drive down costs for large production runs.

In the building field, we use injection-moulded parts for all sorts of critical items, such as spacers, connectors, and protective elements that help ensure structures stand the test of time.

Neumann Steel’s Injection Moulding Innovation

As a proudly Australian-owned and operated company with over 50 years in the reinforcing steel industry, we’ve seen the potential in injection moulding technology. We have a dedicated Plastic Injection Moulding department to foster innovations in this area. This includes our plastic bar “chairs”, which we designed to support reinforcing steel to stay in its intended position during concrete placement. We also have injection moulded spacers and other robust components that utilise this technology.

We’re proud to incorporate injection moulding technology into our reinforcing solutions as part of our ongoing commitment to innovation and quality. For a technical or design discussion, submit an enquiry with our friendly team.