Manufacturing process

OUR RUBBER PRODUCTION METHODS

State-of-the-art technology, quality-controlled production, high delivery reliability, and the right price level are a given. In your collaboration with Gotlands Gummifabrik, you will also notice our commitment and our ability to step in and solve problems even when time is short. We also always strive to make it easy and pleasant to work with us. We hope you appreciate that as well.

Put simply, rubber manufacturing is like baking bread in a large tin soldier mould. Working temperatures and vulcanisation times follow the principles of bread baking. Thick rubber and silicone parts are vulcanised at a lower temperature for a longer time, while thin rubber and silicone parts are finished sooner at a higher temperature.

Mould manufacturing

Would you like to have your own rubber bushing manufactured? Do you have an idea for a new rubber bellows or perhaps a rubber hose? We can assist you all the way from tooling to the finished part.

Injection

The best way to manufacture a molded rubber or silicone component is through injection molding. The tool remains closed during the process, resulting in less flash.

Transfer molding

In transfer molding, one or more pre-formed blanks are placed in a pot. The press is then closed, and a plunger descends into the pot, forcing the rubber through a series of holes.

Kompression formpressning eller transfer maskin.

Compression molding

This production method is the simplest when using a mold tool. It is suitable for small series production, as well as large products where injection volume in an injection machine is not a concern.

Read more about compression moulding

The mould tool consists of an upper and a lower half made of thick, hard-wearing steel. The cavities are created by turning, EDM and/or milling. Once the mould is complete, it is mounted in a press where a hydraulic ram lifts one mould half while the other is fixed in place. The mould is heated to working temperatures between 150 and 180 degrees. The raw material, i.e. the rubber compound, is placed in by hand or injected automatically through channels into the mould cavities. The hydraulic ram presses the mould together with enormous force, and the rubber/silicone is vulcanised to become dimensionally stable. This usually takes between 1 and 5 minutes, but can take up to 20 minutes for larger rubber and silicone parts. Some rubber or silicone parts are vulcanised only briefly in the mould and then post-cured in a heat oven.

After pressing, the parts are deflashed manually or using cryogenic deflashing. Cryogenic deflashing is carried out with a tumbler and/or a cryogenic blaster. Liquid nitrogen is used as the cooling medium. We cryogenically deflash most rubber items. After deflashing, the parts are packed for delivery. Sometimes we assemble the rubber item to deliver a complete rubber product.

Many products are bonded after production, most often parts made of silicone.