injection molding

Injection molding is a process used to create objects from plastic materials. It involves heating the plastic until it becomes molten and then injecting it under pressure into a mold. Once inside the mold, the plastic cools and solidifies into the desired shape. This method is efficient for producing many identical parts, especially smaller ones, with cycles that can be very rapid.12

The process typically uses thermoplastics, which are heated above their melting or glass transition temperatures. The material is melted, shaped, and then cooled to become dimensionally stable. In a common type of machine, a screw melts the plastic using mechanical energy and auxiliary heaters. The screw then acts as a ram to force the molten plastic into a cooled mold. After the plastic solidifies, the mold opens, and ejector pins push the finished part out.1