Venting is one of the most crucial, but often overlooked, aspects of mold design and manufacturing. Parting line vents typically include a primary vent and secondary and tertiary relief channels. The primary vent should be deep enough to evacuate air and gases quickly but not so deep as to create flash. Polishing the vents helps [...]
For cold runner systems, the runner is the first place where air and gases can be removed during injection. To assess whether runner venting is necessary, consider the following factors. Hot runner systems feeding the part directly do not have a large volume of air and gases ahead of the melt that need to be [...]
3D printing provides a significant advantage by enabling users to quickly produce prototype mold and die inserts and short-run manufacturing of complex designs. However, years of testing reveal that specialized, porous mold steels can compete with today’s metal 3D printed steels, yielding a more consistent, stronger product with improved venting performance. Ultimately, the best manufacturing [...]
It seems intuitive that when forcing molten plastic into a cavity filled with air, the air has to be displaced in order to completely fill the cavity. How Air Can Be Removed Air within the cavity can be removed by one of two methods: traditionally, the flow front of molten plastic forces the air out [...]
Venting molds is extremely challenging because you must create a gap in the molding surface large enough for the gas to escape, but small enough so plastic does not leak out. A very fine line exists between gas traps and flash, and not crossing this line is a constant balance. As molds get more complex, [...]
Proper mold venting is essential for producing quality parts. During the molding process, the air contained in the mold needs a way to escape, otherwise the melt will compress and trap that air in the cavity. A combination of melt pressure and high temperature will then ignite the oxygen (called the “diesel effect”), causing burnings [...]
Venting is one of the most important aspects a mold technician can get right when tweaking a new plastic injection mold for production. When vents are not designed and executed properly, problems can occur. […]