Injection molding: complex-shaped parts
Injection molding is a method of producing complex-shaped parts by injecting molten rubber compound into a closed mold under high pressure. This method is the ideal choice when high dimensional accuracy, repeatability and series-production speed are required.
How does injection molding work?
The process takes place on automated machines and consists of several precise stages.
1. Material feeding
The rubber compound (in strip or granule form) is fed into the machine's barrel. Here a rotating screw pushes the material forward and, heating it to around 70–100 °C, makes it flowable.
2. Injection
The softened material is injected under high pressure into the cavity of the closed mold. The pressure ensures that the material fills even the finest details, which allows complex geometries to be reproduced accurately.
3. Vulcanization and cooling
The mold is kept heated and the material is vulcanized in it. Once the cross-links have formed, the part solidifies and is removed from the mold.
Advantages of injection molding
- High precision: complex and fine-shaped parts are obtained at the same dimensions again and again.
- Fast cycle: thanks to automation, large series are produced in a short time.
- Low waste: because the material is injected directly into the mold, losses are minimal.
- Metal reinforcement: rubber-to-metal bonded parts (for example, seals with fixings) can be made.
When is injection chosen?
Injection molding is mainly suitable for small and medium-sized, complex-shaped parts — cuffs, shock-absorber mounts, valves, O-rings and special-shaped seals. Material selection and Shore hardness are determined according to the application conditions.
For parts with a large flat surface or a simple shape, compression molding is often more economical, while for long profiles extrusion is used. Choosing the right method directly affects both cost and quality. You can find information about our production capabilities in the manufacturing section.
Quality control
Every batch is tested in our own laboratory — hardness, tensile strength and dimensional conformity are checked. You can read about this approach on our quality page.
Do you need a complex-shaped rubber part? Take a look at our products and contact us to discuss the most suitable solution for your project.