Silicone Rubber Compression Molding

Why compression

Compression moulding puts a measured preform straight into an open cavity and closes the press on it. Tooling is simpler and cheaper than injection tooling, there is no runner system and no sprue waste, and the process handles high consistency solid rubber that is too stiff to inject.

It is the right process for flat and shallow parts, for large surface area gaskets, for keypads and for any programme where the tool cost has to stay low relative to the order quantity.

How we run it

• Rubber is mixed and colour matched in a dedicated clean mixing room, then blanked to weight so that each cavity receives a consistent charge.
• Presses run to a fixed temperature and time recipe. Flash is torn and trimmed at inspection, and parting line quality is checked under a microscope on parts where it matters.
• Where a part must show no parting line at all, we finish it with a surface grinding step rather than accepting the witness mark.

Typical parts

• Silicone, EPDM, NBR, neoprene and butyl gaskets and sheet seals.
• Silicone rubber keypads and keyboards, including conductive pill and backlit designs.
• Bellows, boots, grommets, bushings, stoppers and O rings.
• Housing seals and washers, including backing adhesive versions.