Shenzhen Alu Rapid Prototype Precision Co., Ltd.

Overview of Plastic Molding

Plastic molding is a versatile manufacturing process used to create a wide range of products, from small components to large containers, by shaping molten or softened plastic into a desired form using a mold. There are several types of plastic molding processes, each suited to different product shapes, volumes, and materials. The choice depends on factors like production scale, part complexity, and cost. Below is a summary of the main types, including brief descriptions and basic steps.

Detailed Guide to Injection Molding (Most Common Method)

Injection molding is the most widely used plastic molding technique due to its efficiency for medium- to high-volume production of precise parts. It requires an initial investment in a custom mold (tooling), but the per-unit cost drops significantly with scale. Before starting, design and prototype your part (e.g., using CAD and 3D printing), then fabricate the mold—typically from steel or aluminum. Once ready, the process follows these six steps:

1.Clamping: Secure the two halves of the mold (clamshell-style) together using a machine press to create a sealed cavity.

2.Injection: Feed plastic pellets into a heated barrel to melt them into liquid. Inject the molten plastic into the mold under high pressure, ensuring even filling.

3.Dwelling: Apply additional pressure to force the plastic into every detail of the mold, compensating for shrinkage and ensuring uniformity.

4.Cooling: Allow the mold to cool (often with water channels) so the plastic solidifies into the desired shape. This step determines part quality and cycle time.

5.Mold Opening: Slowly separate the mold halves using a clamping motor to avoid damaging the part.

6.Ejection: Use ejector pins or bars to push the solidified part out of the mold. Trim any excess material (flash), which can often be recycled.