The injection molding setup consists of the molding machine, the mold, and the plastic material.
For simplicity, plastic injection molding is in stages. Below is a stepwise explanation of how it works.
1. Melting Stage
The first step is to melt the plastic pellets;
Then, place the pellets into the machine’s hopper;
This goes to the barrel, where the rotating screw liquefies the plastic using heat and friction.
2. Injecting Stage
This is the most important step; any mistake may affect the final part’s quality. Here, inject the molten plastic into a mold under high pressure and at a uniform speed.
3. Cooling Stage
Once in the mold, the plastic resin sets and cools. Because plastics are generally poor conductors of heat, this cooling phase may be time-consuming.
After sufficient cooling, open the mold and remove the plastic part using the mold’s built-in ejector pins. At this stage, close the mold and repeat the process to make other identical parts if need be.
This final step involves twisting or cutting any physical defects and applying various surface finish options to make the part glossier as needed.
