Design standard for the runner in plastic injection mold

1.The runner type

the runner design type for plastic injection mold

2.Series diameter(mm)2    2.5   3   3.5    4     4.5     5     6      7      8       (10      12 for reference)

3.How to design the runner diameter for different material

For PE,PA .etc. we can choose smaller diameter,but for PC,PMMA,we choose bigger diameter.

runner design size for plastic injection mold

4. Helpful Tips:
(1). For a U-shaped runner, the size of the runner can be changed by adjusting the H value;
(2). Try to select and use a circular runner;
(3). The sectional area of the runner has to be larger than that of its sub runners. See the following diagram which shows a runner divided into two sub runners. If the no. of sub runners is increased, D1 can be reduced appropriately.

sub runner design