What is injection molding?

During injection molding, plastic granules are heated to their melting point and then forced under pressure into metal molds where the molten plastic hardens into a designated shape. The mold then opens and the newly formed part is removed and inspected, ready for shipment or secondary manufacturing operations. Cycle time is relatively short and large quantities of parts can be produced quickly. Some tools will produce multiple identical parts reducing even further the amount of time needed for mass production making injection molding a very efficient process. 

The advantages of injection molding are many. Injection molded parts will have good mechanical properties such as strength-to weight ratio, low mass and good surface appearance.

Although the initial investment for an injection mold can be higher than other processes, the main advantage of injection molding is the low unit cost, especially when the volumes are high.