Compression molding is a closed-mold composite manufacturing process that uses metal molds with the application of external pressure. The mold — which is a two-part set — is mounted in a hydraulic or mechanical molding press where the molds are heated to 2500 to 4000 F. An engineered composite layup is placed in the open mold cavity, the mold is closed, and pressure is then applied. The pressure remains on the mold throughout the cure cycle, which typically takes place in an oven. Depending on thickness, size, and shape of the part, curing cycles range from less than a minute to about five minutes. The mold is opened and the finished part is removed.
The advantages of compression molding include fast molding cycles and high part uniformity. Also, it offers the ability to mold large components with fairly intricate features – such as holes, inserts or ribs — to be molded in instead of being machined post-mold. Additionally, compression molding achieves very good surface finish, so less part finishing required, contributing to lower costs.
Obviously, the quality of the mold itself plays a crucial role in enabling manufacturers to consistently produce quality parts. Molds can be machined from forged steel, cast iron, and cast aluminum. Along with years of dedicated experience, Century has an established process that has proven to consistently meet delivery deadlines as well as stringent quality requirements.