REACTION INJECTION MOULDING
Process
This is a form of injection moulding that produces components with a honeycomb like centre. It is a cold injection process that does not require pre-heating of moulds or post curing of parts. Two materials are mixed prior to injection; these materials react in the mould to form a solid moulding.
The low pressure process can produce large mouldings – up to 40kgs and in excess of 1m square with sections of 5mm-15mm. The resulting components have a high level of stiffness.
Materials
This process uses a fast acting polyurethane resin.
Products
Products manufactured using this process include:
Business machine housings
Point of sale display components
Containers
Pallets
Office furniture
Sporting goods
Automotive parts
Advantages
Low pressure mouldings mean the mould tools can be manufactured from silicone, resin, modelboard or aluminium resulting in cheaper tooling costs
Fast tool manufacture
High impact strength and dimensional stability
Disadvantages
Parts are more expensive as the surface finish is generally poor needing filling, sanding and painting. Generally a textured finish is used.
Slow cycle times
Expensive raw materials
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