Let’s take a quick look at the injection molding machine cycle from the machine operator’s point of view.
Specific duties vary from plant to plant, but these general tasks will apply to most injection molding plants.
Operators work with injection molding machines in both the automatic and semi-automatic modes. In the automatic mode, the molded parts drop out of the mold as the machine cycles continuously. Or, in some cases a robot is used to remove the parts. The operator may collect and inspect the parts, and sometimes the operator will also separate the parts from the runners.
There is quite a bit more to the injection molding machine operator’s job than may at first be apparent. In semi-automatic operation, the operator first waits for the mold to open. When the mold is completely open but not before, the operator opens the front safety gate door and checks the safety bar. Seeing the safety bar is in place, the operator reaches in between the mold halves and removes the plastic parts. The machine operator should be very careful when handled the newly molded parts. Plastic parts can be scratched quite easily. If the parts will be painted or plated, you’ll have to wear gloves to protect the surface of the plastic.
The operator quickly checks the mold surface and the mold cavities. In some plants, compressed air is used to clean out the mold cavities after the parts are removed. Sometimes a piece of plastic or even a plastic part gets stuck in a mold cavity. If you can remove it with your fingers, do so; if not, call a mold technician or a supervisor. Unless you are experienced and have permission, don’t use any metal tools between the mold halves. You can easily damage a mold. And don’t ever start a new cycle with any piece of plastic in a cavity or on the mold surface. If you do see anything unusual in the mold, call your mold technician or supervisor.
Once the parts have been removed, the operator will close the safety gate and the injection molding machine starts a new cycle.