Plastic Injection Molding

Feb 28,2020 | Views: 1333

Injection molding is principally used for the production of thermoplastic parts, although some progress has been made in developing a method for injection molding some thermosetting materials.

The problem of injecting a melted plastic into a mold cavity from a reservoir of melted material has been extremely difficult to solve for thermosetting plastics which cure and harden under such conditions within a few minutes. Plastic resin is loaded into the feed hopper and a certain amount feeds into the heating chamber when the plunger draws back. The resin under heat and pressure in the heating champer becomes fluid. After the mold is closed, the plunger moves forward, forcing some of the fluid plastic into the mold cavity under pressures. Since the mold is cooled by circulating cold water, the plastic hardens and the part may be ejected when the plunger draws back and the mold opens. Injection molding machines can be arranged for manual operation, automatic single-cycle operation, and full automatic operation.

E-mold specialized in Precision mold, Overmolding mold (Metal insert overmolding or TPU/TPE/TPV overmolding), Hot runner system mold, Unscrewing mold, Multi cavity mold.

The advantages of injection molding are:

1. A high molding speed adapted for mass production is possible.

2. There is a wide choice of thermoplastic materials providing a variety of useful properties.

3. It is possible to mold threads, undercuts, side holes, and large thin section.