Design

Proper location of the gate point will be directly affect the quality of the injection molded parts gate location selection should follow the following principles:

1. Gate location should be chosen in parting surface, so that it would be easier for machining and maintenance.
2. The runner should be designed even, mold flow distance and sectional size in balance can achieved stable molding quality.
3. Gating location should be on the thick-wall area so it ensure the cavity can be filled completed.
4. The mold flow should not be right on the inserts or lifter, high pushing pressure of melt flow would probably deform the inserts.
5. Try to avoid weld marks or weld lines created in the critical surface, changing location of gating and try to make the weld line on uncritical surface.
6. Consider the venting when design the gating, make sure the end of the mold flow have good venting.
7. Gates should be easily removed and gate mark should not affect the appearance of the molded parts.

It's a common way to assemble plastic components or achieve functionality by creating hole features, Location and measurement of holes need to be carefully designed to minimize the complexity of mold manufacturing and negative influence to the part strength, in this article we are going to discuss what elements we should consider when doing rib design.

Rib is a frequently used feature in plastic injection molded parts design for the purpose to enhance the strength of the plastic parts, typical rib design see below figure.

The thickness and location is essential of the rib design. Usually, ribs should be designed with a thickness of 1/2 of the wall thickness to avoid a thick section at the base of the wall, which would cause sink marks on the part surface. Ribs are usually spaced at a distance at least twice the wall thickness to allow enough steel between the ribs for adequate cooling.