Steps For Plastic Injection Molding Process

By Author: Ryan
Total Articles: 9
Comment this article

Plastic injection molding is a manufacturing method that produces plastic components of various sizes, complexity, and applications. A vertical or horizontal injection moulding press, a mould, and raw plastic resin are all required for this procedure. The injection moulding machine melts the plastic resin material, which is then injected into the mould to cool and solidify into the final part or pieces. The method consists of four stages: clamping, injection, cooling, and ejection.


Clamping unit for injection moulding machine


Clamping is the process of attaching each half of an injection mould to the injection moulding machine using a clamping device. The motorised clamping mechanism presses the mould halves together, exerting enough force to hold the mould firmly closed while liquid resin material is injected into the mould cavities.


The time required to clamp and hold the mould closed is determined by the size of the moulding press. Clamping is one factor that can help you decide the size of the injection moulding press needed to create your component. Once you know what ...
... size press your part takes, you'll know which component your injection moulder needs to manufacture your product.


Injection Phase of Resin Raw Material


Injection occurs when raw material is put into an injection moulding press and moved towards a mould by the injection unit. During the progression, raw resin material is melted by heat and pressure. The injection machine takes molten plastic and uses pressure packs to retain it in the mold's cavities.


To achieve correct melt temperatures, a combination of parameters must be used, including the barrel temperature, nozzle temperature, and injection mould. The temperatures of the barrel and nozzle affect the flow ability of polymers throughout the mould. The mould temperature influences both the flow through the mould and the cooling of the moulded component. The barrel and nozzle temperatures should be carefully adjusted. If the temperatures are set too high, there will be an overflow and flash, while setting them too low would result in empty areas.


When constructing a reliable Injection Molding China, two factors are adjusted: temperature and pressure.


Cooling Time for Plastic Injection Moulding


Cooling the molten plastic inside the mould cavities causes it to solidify into the part's form. Cooling commences within the mould as soon as it comes into touch with the internal mould surfaces. The mould will not open until the requisite cooling period has passed. The resin raw material manufacturer makes suggestions for determining the injection mould temperature. The component and mould designs, as well as the resin raw material utilised, all influence cooling timeframes. The injection mould design includes internal cooling.


Ejection of Plastic Part


Ejection happens once the component has cooled sufficiently. When the clamping unit opens the injection molding, an ejection mechanism pushes the part(s) out. During the cooling process, the component shrinks and sticks to the mould cavities, necessitating force to remove the part. Following the ejection and removal of the portion or parts, the mould shuts to allow the injection of the next shot, so initiating the next cycle.