10 Parting line design principles for Injection Molds

Published in:2018-04-04


1. Mold Clamping force

The lateral clamping force is smaller than longitudinal clamping force. For a large plastic part, should be put the biggest projected area part on the parting surface and horizontal with Mold opening direction. the smaller projected area as side parting.

2. Demold's require

The parting line is in order to smooth demould, take out products smoothly. So a parting line's location should be on the Product's part which has biggest cross-section size, this is the 1st underlying principle.

3. Parting line Shape

The general products, often use a parting line which vertical with a injection machine's mold opening direction. use other shapes of parting line under exceptional circumstances.

4. Products' Appearance & Quality

The parting line should not on products' smooth surface. products' surface should not appear split line or some line that esthetic effection. For some products' concentricity requirement, need put all parts which has concentricity requirement on a same side.

5. Layout

Before decide the layout of the product, parting line's choice need as far as possible to prevent parts to take shape a side hole or a side buckle, to avoid use complex mold structure.

6. Advantageous to Demold

in general, lots of molds' emptier on the B plate, so when design the parting line, Should be as much as possible let plastic part staying on B plat when demolding.

7. Consider lateral Demold distance

8. Easy to Process mold components

9. Conducive to venting

When take a parting line as the main venting part, need design parting line on the end of a plastic flowline.

10. Best R (Radius)design.