Moulded rubber is used to make all kinds of components for machinery, vehicles, domestic appliances and more. But how much do you know about the moulding process? The likely answer is “not very much” unless you are involved in the industry.
Types of Moulding
There are various processes used in moulding rubber. They all use the same basic principle, though, which is that the raw rubber compound is subjected to heat in a mould. In compression moulding, rubber material is placed in a heated mould and pressure is also applied to help form the shape of the component.
Injection moulding is the other common technique used. Here rubber pellets are heated and then injected into the mould in liquid form. Once the mould cavities are filled, again the rubber is subjected to pressure to get it to form the right shape. Once it’s cooled, the components can be removed from the mould and detached from the moulding sprues. Rubber moulding involves some large machinery and dangerous chemicals, so it’s important that it is carried out safely.
Pros and Cons of Injection Moulding
The most common process for making rubber mouldings used by companies like https://www.meadex.co.uk/ is injection moulding. There are a number of reasons for this. It’s a quick process and ensures that a minimum amount of material gets wasted. Because the rubber material is melted before entering the mould, it flows more evenly, so producing consistent results and a reliable end product with minimal need for finishing after the process. Injection moulding can also be automated and is therefore ideal for mass production.
As with any process, there are some negatives too. Firstly, injection moulding requires specialist machinery, so set-up costs are high. There are also tooling costs involved in creating the moulds needed. In mass production situations it’s essential to go through a prototyping phase and ensure that the components are fit for purpose before production begins. This may involve adjustments to or re-tooling of the moulds.
For one-off requirements or if costs need to be kept low, injection moulding may not be the ideal method. However, if you need to produce a complex design with consistent quality of product, the extra costs of tooling up for using injection moulding are well worth it.