Published - 12th Oct 2021
Rubber moulding is a rubber manufacturing process in which raw rubber compounds are shaped, and moulded, to fit with the requirements of a customer’s design brief.
There are several distinctive processes when it comes to the manufacturing of rubber mouldings, most of which involve the use of heat and pressure to create the desired mould structure.
We look closer at rubber mouldings, both what they are used for and how they are made.
Rubber moulding is a key manufacturing process, enabling the production of a vast range of components suitable for a multitude of industrial uses.
Natural rubber is still commonly used within the manufacturing process. However man-made, synthetic variations are also becoming a popular choice thanks to greater levels of durability and longevity, without losing the traditional levels of strength and versatility.
Neoprene, ethylene propylene diene monomer (EPDM) and silicone are some of the most common manmade materials used within rubber moulding.
Thanks to incredible levels of flexibility and versatility, there are countless applications for rubber moulding – here are the most common uses:
With increases in scientific development, the potential for rubber mouldings is quickly growing, with more and more uses introduced regularly.
The aim of rubber moulding is to manipulate and shape rubber into a specified form. The process also subjects the rubber to chemical processes that harden the polymer chains within the raw rubber itself, preventing the links from moving independently and toughening the structure, giving the product its durable nature.
The process begins with engineers drafting a suitable design, taking into account the client brief and requirements.
Once the design is complete, it is transformed into a metal mould. Steel moulds are commonly used in the manufacturing process due to their long-term economic value, but some moulds are made of hardened steel, beryllium hardened copper or certain forms of aluminium.
From this point, there are three distinctive moulding processes generally used.
This method uses a heated hydraulic press into which the mould is fitted. The rubber compound is prepared by extruding and cutting, or cutting from sheet into a pre-determined weight and shape. These pre-forms are referred to as blanks. The blank is placed directly into the cavity. The mould is then closed and heat and pressure are applied to vulcanise (cure) the rubber.
This method uses similar equipment to compression moulding except the blank is placed in a transfer chamber usually located above or below the mould cavity. A piston is used to transfer the rubber via a feed gate into the cavity when the mould is closed in the hydraulic press. The part is then cured as the compression moulding process
This requires specialist injection equipment with the uncured rubber compound usually prepared as a strip which is fed directly into an injection unit that plasticises and prepares a predetermined “shot weight”. The rubber is then injected directly into the cavity where it is cured.
Compression moulding is the most commonly used moulding technique thanks to its simplicity in comparison to both transfer and transfer injection moulding processes.
Rubber moulding holds an essential role within the rubber production industry. It provides highly flexible solutions for a wide variety of industries, with the ability to tailor components, parts, configurations and designs to accurately fit the requirements of the client.
Rubber moulding processes offer an efficient and often cost-effective method of producing high-precision products with little to no waste.
Access to a variety of moulding methods allows engineers to produce rubber products en masse, as well as larger pieces that require high levels of intricacy.
From aerospace and agriculture to electrical, food and beverage and medicine, rubber moulding serves a limitless number of industries thanks to its flexible, durable and fully customisable nature.
At Industrial Rubber, we manufacture high-quality rubber parts using top-class moulding processes, ensuring accuracy and speed of delivery.
Get in touch to find out how we can help improve your business’ manufacturing processes.