August 8, 2025
Plastic injection moulding is a common plastics processing method used to make a variety of plastic products. Below are the general steps involved in the plastic pellet injection moulding process:
Preparation of raw material: first, plastic pellets need to be prepared as raw material. These pellets are usually supplied by the plastic pellet manufacturer and are heated and melted during the injection moulding process.
Heating and melting: The plastic pellets are placed in the hopper of an injection moulding machine, where they are heated and melted to convert the solid plastic pellets into a flowing molten state. The injection moulding machine usually includes a screw that rotates and pushes the plastic pellets into the heated barrel.
Injection: When the plastic pellets are melted into a liquid state, the injection moulding machine uses a screw to inject the melted plastic into the mould. This step is called injection.
Mould Sealing: Once the plastic has filled the mould, the mould is sealed to ensure that the plastic retains its desired shape in the mould.
Cooling: Once the plastic has filled the entire mould, it needs to be cooled to allow the plastic to solidify. This is usually achieved by introducing cooling water around or inside the mould.
Mould Opening: Once the plastic has cooled sufficiently, the mould is opened and the moulded plastic product is ejected. This process is called mould opening.
Machining and Trimming: At times, the moulded part may require further machining and trimming to meet the requirements of the final product. This may include trimming, sanding, assembling, and so on.
The exact details and conditions of these steps may vary depending on the type of plastic used, the product design and the type of injection moulding machine. In actual production, the operator needs to adjust and control the injection moulding process parameters according to the specific conditions to ensure the quality and performance of the final product.
