INJECTION MOLDING PROCESS

INJECTION MOLDING PROCESS

                  

         Injection molding is a process of introducing the molten thermo-plastic material into a cavity or impression of the desired shape under pressure and allowing the molten material to solidify. No chemical reaction occurs during the molding process. (Any reaction that occurs would be a degradation reaction, which should be avoided). It is one of the most common and versatile operations for mass production of complex plastics parts with excellent dimensional tolerance. It requires minimal or no finishing or assembly operations. The molds are generally made out of Tool Steels and are provided with channels for cooling, heating and venting for efficient work of tool. When intricate shapes with external and internal undercuts are required, molds incorporate devices such as Side cores and Slide cores become necessary. Finally troubleshooting is carried out to the tool so as reduce the scrap and improve the part quality

 Advantages of Injection Molding Process:

 Parts with good surface finish can be produced at high production rates.

 For intricate shape and small parts, the process is economic way to fabricate.

 Parts can be molded with metallic or non-metallic inserts.

 Close dimensional tolerances can be maintained.

 Relatively low labor cost per unit is required.

 Minimum scrap as runner, gate and sprue can be reground and used.

Limitations of Injection Molding Process:

  High tool cost.

  Expensive molding machine.

  High maintenance cost.

  High power consumption.

Initial Settings to be done to the Machine:

          Set the barrel temperature, injection pressure, screw speed and shot weight.

          Set the injection time, cooling time, etc.,

          Clamp the mold halves in the machine platens.

          Set the ejection stroke.

          Adjust day-light.

          Trouble shooting