blank.gif (43 bytes)
800.776.0380
Home About Us Resource Center Contact Us WebFTP
Download PDF of this page  Print this page
Home » Injection Molding

Injection Molding

Injection Molding is the process of pushing (or forcing) melted plastic into a mold cavity. Material is fed into a heated barrel, mixed, and forced into a mold cavity where it cools and hardens to the configuration of the mold cavity. There are six steps to the injection molding process:Clamping, Injection, Dwelling, Cooling Mold, Opening, and Ejection

The process starts with a mold, which is clamped under pressure to accommodate the injection and cooling process. Then, pelletized resins are fed into the machine, followed by the appropriate colorants. The resins then fall into an injection barrel, where they are heated to a melting point, and then injected into the mold through either a screw or ramming device.

Then comes the dwelling phase, in which the molten plastics are contained within the mold, and hydraulic or mechanical pressure is applied to make sure all of the cavities within the mold are filled. The plastics are then allowed to cool within the mold, which is then opened by separating the two halves of the mold. In the final step, the plastic part is ejected from the mold with ejecting pins.

Injection molding machines, also known as presses, hold the molds in which the components are shaped. Presses are rated by tonnage, which expresses the amount of clamping force that the machine can exert.

Lomont IMT  •  Paragon Products
Site Map  •  Privacy Policy