Product design
Design is one of the most important steps when it comes to any production process. Design is implemented in terms of function, aesthetics, manufacturing and assembly. Planning and creating a successful design plan is key in avoiding mistakes and forming a straightforward, successful process.
Mould design
One the exterior design is complete, the mould structure needs to be designed prior to the injection moulding method. Mould design is another opportunity to prevent mistakes further down the line and prepare for the upcoming steps. Moulds and the injection moulding tool are commonly made from these materials…
- Hardened steel
- Pre-hardened steel
- Aluminium
- Beryllium-copper alloy
Clamping
Before the mould is injected with a raw material, both halves of the mould have to be securely closed through a clamping unit. These halves are then attached to an injection moulding machine and one half can slide. The chosen material is then injected while the clamping unit pushes the halves together. Both halves are held together tightly as the material is injected.
Injection
Plastic pellets are fed through a hopper, into the injection moulding machine. These pellets travel towards the mould and the pressure begins to melt the pellets. Injection time can be estimated by different factors including injection pressure, power and shot volume.
Cooling
The cooling stage of injection moulding involves the plastic inside the mould beginning to cool down. As the plastic cools, it will create the desired shape. Once the cooling period has elapsed, the mould can be opened.
Judging from the wall thickness and the thermodynamic properties, the cooling time can be simply estimated.
Ejection
The last stage is that of ejection. This process is done through an ejection system in which the mould opens the part it is pushed out from. Force is used as the part shrinks and sticks to the mould. This will then be shut again and another shot can be injected, starting the injection moulding process once again.
