Innovative Solutions for High-class Prototypes and Short Runs

Plastic parts in large series are generally produced by injection molding. The building of the steel mold for this production method is complex and costly and should therefore only be used when a large number of parts warrants its use.

The RIM technology can be used to produce a smaller number of units up to 1,000 parts in a fast and cost-efficient way. In the case of reaction injection molding (RIM), a two-component PUR mixture is injected into a mold with a 2K mixing and dosing system and cured in an exothermic reaction, to produce a detailed part with defined properties, simulating thermoplastic materials.

Compared to thermoplastic injection molding, the PUR resins have better flow behaviour due to their lower viscosity and can achieve greater flow paths at the same wall thickness. Typical RIM applications include bumpers, sills and spoilers.

Sika offers a wide range of SikaBiresin® RIM systems, covering the properties of thermoplastic systems. The 2K PUR resins have a low viscosity and enable the production of large size, complex components with low wall thicknesses. The processing time of most RIM systems lies between 1 to 3 minutes. Due to this fast reaction time, the parts can be demolded after 5 to 20 minutes, which makes the production of small number of units more profitable. Furthermore the Sika RIM portfolio offers special RIM products with high impact resistance, high temperature resistance, long pot life for production of large parts as well as special certifications for the automotive industry.

Applications

  • Bumpers
  • Sills
  • Spoilers

Benefits

  • Fast realization of cost-effective prototypes and small series with defined material properties
  • Cost-effective production of rigid housings and coverings simulating thermoplastic systems
  • Low costs for tool production
  • More safety through high reproduction accuracy in the manufacturing process

Further Reading