Injection Molding

Injection Molding Overview

What is injection molding?
Injection molding is a method of producing plastic parts.This is done with an injection molding machine. The shape of the part to be injection molded controlled by the geometry of the injection mold. The injection molding machine has two basic parts; the injection unit, which melts the plastic and then injects or moves it into the mold, and the clamping unit, which holds the injection mold. The unit clamps the mold in a closed position during injection, opens the mold after cooling, and ejects the finished part.

Injection molding is a commong method of producing intricate plastic components in high volume.

Injection molds are made from hardened tool steel, although aluminum may be used for some low volume applications of injection molding. Injection molds can vary from simple open-shut injection molds, single cavity injection molds to complex multi-cavity injection molds with moving cores, stepped shut-offs, unscrewing devices. Due to the tonnage used in this high pressure process, proper materials , supports, parting line locks etc. must used to ensure the life of the mold. Cavities may be polished or textured to achieve a desired finish on the injection molded part.

Injection molding is perfromed by companies called molders. Some molders also design and build injection molds. The most common materials injection molded are plastic (plastic injection molding) and rubber (rubber injection molding).

Metal can also be injection molding. This is known as metal injection molding (MIM). Metal inection molding is relatively new but has gained popularity quickly. Metal injection molding produces intricate metal injection molded parts very economically.