Injection Molding Thermoset Materials

As a type of plastic material, thermosets can be molded in similar molding processes as thermoplastic materials such as nylon, ABS, and polypropylene. Thermosets can be injection, compression, and transfer molded. Each molding process offers different benefits and disadvantages depending on the finished part’s geometry, assembly, and commercial aspects of the program. OEMs and molders must take into consideration all variables of a part and how it is used to determine the best molding process to make the part. While there may be multiple molding processes that can successfully produce the same part, some processes may be more advantageous based on pricing or product and quality specifications.

Injection Molding Process

Using an injection molding process is a very common molding process for thermosets. Injection molding offers a fast cycle time compared to a compression or transfer molding process, allowing a molder to produce a higher throughput of production in a day or shift with an injection process. Industries such as automotive, electrical, and home appliance markets rely on injection molding process for thermoset components that need to be produced in high quantities and shipped to customer plants quickly. An injection molding process may save as much as 50% of machine time over a production run with it’s faster cycle times and throughput compared to a compression molding process. Designing a thermoset part to be produced with an injection process allows for design flexibility with the ability to move parting lines, gate locations, and ejector pins to preferred locations of a part. Molders are also able to run injection molds automatically without the need for an operator to demold the parts and continually feed material to the mold. Because of these economies of scale, injection molding is a very common process type that allows molders and OEMs to produce a high number of parts at a low cost to manufacture.