RIM (Reaction Injection Molds)/Foam Molds

RIM (Reaction Injection Molding) and foam molds are an excellent fit for Castek’s core competencies. Castek’s aluminum foundry allows us to provide “as cast” aluminum open or closed pour foam molds as an option to CNC machined sand castings or aluminum billet molds. This allows Castek to fit the best mold type for each application. RIM has become an ever increasingly used material and has grown in terms of market share over competing processes.

The RIM process can have many benefits over competing thermoplastic or other high tonnage moldings with respect to capital and tooling outlay. The molding pressures in RIM are fractional as opposed to injection molding thus lower capital equipment costs and related tooling. Dependent on part geometry and part volumes aluminum sand castings or aluminum billet materials can be used for the RIM molding process and can provide significant cost savings or more expensive P20 steel thermoplastic molds.

Castek serves many market segments within the RIM process. Many of the final products are used in automotive soft trim applications. Some of which are:

  • Automotive carpet foam molds
  • Seat molds
  • Door bolsters and arm rest molds
  • Center console molds
  • Engine cover and sound deadening molds (NVH) noise, vibration, and harshness

Many of the Castek foam mold designs incorporate foaming the substraight or injection molded good to the back side of the foam. This process is more commonly know as “foam in place” tooling. This foam in place tooling option eliminates post operation labor to post glue the foam bun onto the substraight. Castek has several designs for accurate and positive shut off between the foam cavity and the substraight. In some instances, a hard shut off or parting line can be utilized. Dependent on part geometry and part complexity Castek often employs soft seals or cord stock / rope seal shut offs into the mold design to achieve a clean part at the parting line each and every time.

Castek design and builds numerous foam mold types for several different PU / polyurethane densities and types. Some of which are:

  • Flexible foam systems
  • Rigid foams
  • Structural foams
  • LFI – Long fiber injection
  • Elastomers

Many of the above applications can demand large aluminum molds for consumer good markets and other large urethane parts. The unique Castek aluminum casting process allows excellent surface quality on the cavity mold surface. Castek can media blast or acid etch the finished mold surface to provide many different textures and surface aesthetics on the molded parts. This enhanced foundry process has allowed Castek to use CNC machined aluminum sand castings in place of the more expensive aluminum billet process in certain applications.