Abstract: Method and apparatus for molding polymeric materials using the reaction injection mixing (RIM) technique of combining two or more chemically reactive components immediately prior to their introduction into a mold. The invention is more particularly adapted to RIM molding of polyamide (nylon) type polymers, but is also useful for urethane polymers. In either case the polymers may be of the unfilled or of the reinforced type. Modification of conventional RIM technique is made to meet higher component temperature conditions required for nylon molding as compared to urethane polymers, for example. A characterizing feature of the invention is the employment of an attempering "oil tracer" system comprising casings and jackets enclosing the flow paths of each of the several reactive components, and the flow therethrough of a temperature-controlled oil or other fluid medium in heat-exchange but non-fluid communication with the reactive components.

Abstract: Multi-station reaction injection molding apparatus is disclosed for in-place foaming of polymerizable resins in articles advanced along a production line, as for example in the manufacture of insulated appliance housings such as refrigerator cabinets. The articles are selectively diverted from a feed conveyor, one to each of a plurality of pour stations adjacent the feed conveyor. At the stations, injection of foamable resin mix is accomplished by reaction injection type molding heads which combine at least two liquid resin components. These components are suitably catalyzed to react and form a cellular or foamed polymerized resin. The liquid components are separately but continuously supplied to respective supply manifolds to which all of the heads are connected in parallel by shunting ducts. Excess unmixed liquid components are returned separately from each of the heads through recycle shunting ducts to respective recycle manifolds.

Abstract: Multi-station reaction injection molding apparatus, and method, are disclosed for in-place foaming of polymerizable resins in articles advanced along a production line, as for example in the manufacture of insulated appliance housings such as refrigerator cabinets. The articles are selectively diverted from a feed conveyor, one to each of a plurality of pour stations adjacent the feed conveyor. At the stations, injection of foamable resin mix is accomplished by reaction injection type molding heads which combine at least two liquid resin components. These components are suitably catalyzed to react and form a cellular or foamed polymerized resin. The liquid components are separately but continuously supplied to respective supply manifolds to which all of the heads are connected in parallel by shunting ducts. Excess unmixed liquid components are returned separately from each of the heads through recycle shunting ducts to respective recycle manifolds.