Injection Mold Runner And Gate Design

Hobbyists typically remove the parts of a model kit from the runner using a sharp craft knife or razor saw.

Injection mold runner and gate design.

The gate is the location at which the molten plastic enters the mold cavity and is often evidenced by a small nub or projection the gate mark on the molded piece. There are three channels in which the plastic flows from the injection molding machine into the part cavity. With each branch going back to the sprue the runner s diameter should increase 10 to 15 and then intersect the sprue base. This is the contact point between the machine and the mold.

First every mold has a sprue. While it is true that those plastic material may be reused in the form of regrind their presence nevertheless means a reduction in the performance of the injection molding machine inasmuch as they. Many scale model kits are made from injection molded plastic. Ates and runners are an essential part of the injection molding process.

The spherical surface sr of the mold sprue should be 1 2mm larger than the nozzle sr of the injection molding machine. The rule of thumb in traditional mold design is that the runner should be round and equal to the part s nominal wall stock at the gate. For the complicate product it s necessary to make mold flow analysis to help design a good runner system and gate position. 1 injection molding machine nozzle and sprue matching.