Design standard for the runner in plastic injection mold

1.The runner type

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.

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.