Silicone rubber is a versatile material used in a wide variety of applications from medical devices to toys. One of the most common methods for manufacturing silicone rubber products is through moulding. This post will explore the two main types of silicone rubber moulding – compression moulding and liquid silicone injection moulding.
Compression moulding is a simple and cost-effective process that is often used for small batches of products. In compression moulding, the silicone rubber is placed in a heated mould and then compressed under pressure. The heat and pressure cause the silicone rubber to vulcanise, or cure, into the shape of the mould.
Liquid silicone injection moulding (LIM) is a process for manufacturing silicone rubber products in which the two components of silicone rubber are mixed in a precise ratio and then injected into a heated mould under high pressure. LIM is commonly used for products such as baby bottles and teats.
Injection moulding is a more complex process, but it is also more efficient for large batches of products. It has several advantages over compression moulding, including:
Faster cycle times: LIM curing times are typically much shorter than compression moulding, which can lead to significant productivity gains.
Less waste: LIM is a very efficient process, with minimal material waste.
Flexibility: LIM can be used to produce a wide variety of complex shapes and features.
Excellent surface finish: Products typically have a very smooth and uniform surface finish. For silicone moulding UK, visit a specialist such as https://www.meadex.co.uk/.
There are five steps involved in LIM moulding. First, a mould needs to be designed and accurately made from steel or aluminium. Then, the silicone rubber needs to be prepared in two components, a base and a catalyst and precisely mixed and heated. The silicone rubber then needs to be injected into the mould using a hydraulic press before curing under heat and pressure. Once the silicone rubber has cured, the product is removed from the mould. The product may need to be trimmed or cleaned before it is ready for use.