RIM & SRIM Molding

Hydraulic Presses, Reaction Injection Molding (RIM)

Reaction injection molding (RIM) is a relatively new processing technique that has rapidly taken its place alongside more traditional methods. Unlike liquid casting, the two liquid components, polyols and isocyanates, are mixed in a chamber at relatively low temperatures (75° – 140° F) before being injected into a closed mold. An exothermic reaction occurs, and consequently RIM requires far less energy usage than any other injection molding system.

Typical Materials:

  • Rigid Structural Foam
  • Low-modulus Polyurethane
  • High-modulus Polyurethane
  • Epoxy Resins

Reinforced RIM (R-RIM) consists of the addition of such materials as chopped or milled glass fiber to the polyurethane to enhance stiffness and to increase modulus, thus expanding the range of applications.

Typical Materials:

  • Polyurethane
  • Glass-Filled Polyurethane
  • Epoxy Resins

Structural Reinforced RIM (SRIM)

Low-viscosity polyurethane RIM systems can be injected into a mold through glass mats or preformed glass fiber mats to produce very stiff, high-strength structural RIM (SRIM) parts. After the glass-filled preform is loaded into the open mold, the mold is closed and the polyurethane resin is injected where it permeates and surrounds the preform to form the part.

SRIM is used more commonly used in demanding structural applications. This process promotes non-uniforms cross-sections, and allows designers to add strength where required. The overall outcome is a single component with the optimum weight for the physical requirements.

Typical Materials:

  • Polyurethane
  • Glass-Filled Polyurethane
  • Epoxy Resins

Request a quote for French hydraulic presses or contact our engineers to learn more about how our hydraulic presses can be designed for your molding process.