Engel, Top Grade Molds Present Conjection Process for Injection Molding

The new coinjection process, which Engel has developed in collaboration with Top Grade Molds, is said to enable higher recycled material content in the production of pails versus the conventional processes for sandwich injection molding.

Development of the coinjection process follows global pressure to use more recycled plastic material, Engel says. For example, the process is said to use more than 30% of recycled material in the core during the production of five-gallon pails. Coinjection makes it possible to concentrate the recycled material in the component’s core and encapsulate it in a layer of virgin material, Engel says. The virgin and recycled material are of the same type to ensure that the sandwich-molded parts can also be recycled at end of life. In general, this process can be used for a variety of applications. 

Further, to achieve high recycled content without compromising product quality, the system switches from recycled to virgin material close to the cavity, directly at the injection nozzle, combining the two molten plastics. In addition, the new system uses a needle shut-off hot runner.

Engel will be exhibiting the new process at Amerimold 2021.

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Exhibitor: Engel

Booth M-926 (P)