Two Plate Molds
Cold Runner Molds
Conventional Molds
Two plate molds are often referred to as cold runner molds or conventional molds. This is to indicate their simple open and shut setup with the molded part formed between two plates.
One section of the mold is called the stationary side or injection half. This is the side of the mold that sits against the portion of the molding press that does not move and it is also normally the place where the plastic enters (injected) into the mold.
The other section of the mold is called the moveable side or ejection half. This is because it is retained on the portion of the molding press that moves back and forth to open and shut the mold. Also included with that movement of the press, is a bar in the press that actuates the ejection of the part from the mold.
Plastic pellets are melted by the injection molding press in it’s screw and barrel area. The melting is caused both by external heating bands around the barrel and by the screw turning within the barrel to causing friction and therefor sheer heat in the plastic.
The melted plastic that has moved down the length of the screw to an area in front of the screw flights is pushed forward out or the barrel (injected) and into the runner system of the mold.
The plastic moves through the runner system in the mold and through a gate area into the recess in the tool for the plastic part to be formed. need cold runner mold for your project? Contact us to get a price.