Rapid Custom ManufacturingRapid Custom Manufacturing

Reaction Injection Molding Large Parts

Project Overview:

Manufacturing Process: Reaction Injection Molding (RIM), M6 Insert
Molding Material: Polyurethane (Hei-Cast 8636-75)
Tooling Material: Epoxy Resin, Silicone Rubber
Part Dimensions: 743 × 512 × 315 mm (Thickness: 5/7/10/20 mm)
Quantity & Lead Time: 50 Units, 25 Days

This was an Engine Casing that was originally manufactured by the sheet metal fabrication with lots of welding. To save cost, customer modified the design of this casing to be Reaction Injection Molded. The different wall thicknesses of 5/7/10/20 mm brought challenge to shrinkage control.
Reaction Injection Molding ToolingOur RIM tooling was usually made of Epoxy Resin & Silicone Rubber, the silicone rubber pieces were usually replaced after 100 shots.
RIM ToolingLow-Pressure & Room-Temperature Injection Molding required fairly low mold locking force, thus the simple clamps were fine for our RIM process.
One shot of injection molding time was around 40 seconds. More big size and volume of the part, More time of the reaction injection molding.
Insert Molding and Overmolding were also feasible for our RIM process. 4 stainless steel M6 nuts were inserted for injection molding.
The high strength of our RIM parts had our RIM process low volume manufactured the large shell parts properly, economically and quickly.
The finished RIM parts for delivery. The parts were packaged economically and safely to be delivered by cheap sea freight that took around 25 days.