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How Plastic Injection Works

How Plastic Injection Works

Plastic injection is a method in which a thermoplastic or thermosetting moulding compound is first uniformly plasticized in a heating barrel, and then pushed into the cavity of closed mould by a plunger or a moving screw. The injection service of China Mould Company is applicable to almost all thermoplastics.


In recent years, injection moulding has also been successfully used to form certain thermosetting plastics. China's mould manufacturing is maturing. Injection moulding has a short moulding cycle (from a few seconds to a few minutes), and the quality of moulded products can be from a few grams to tens of kilograms. Moulded products with complex shapes, accurate dimensions, and metal or non-metal inserts can be formed at one time. Therefore, the method has strong adaptability and high production efficiency. The injection machine for injection moulding is divided into two categories: plunger injection machine and screw injection machine, which consists of three parts: injection system, mould clamping system and plastic mould.


Working principle

Similar to the syringe used for injection, it is a technological process of injecting the plasticized plastic in molten state (i.e. viscous flow state) into the closed mould cavity with the help of the thrust of the screw (or plunger) and obtaining the product after solidification and shaping process.

Injection moulding is a cycle process, and each cycle mainly includes: quantitative feeding, melt plastification, pressure injection, mould filling and cooling and mould take-out. After removing the plastic parts, the mold is closed again for the next cycle.

HanKing Mould is a representative company of injection mould service in China.


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