Terms of plastic mould and plastic injection molding

Even though plastic mould and plastic injection molding is not a new technology to us, but it is still a little bit complicated. If you are plastics-related person, you should at least have some basic idea on what those terms refer to.

Perhaps it’s hard to know all terms of plastic mold and plastic injection molding, so we sort out some common and useful ones to share as below:

Injection molding process picture

Terms of Plastic Injection Mold Making

Mold – A steel(some of aluminum) made device that used for injection molding to obtain plastic parts.

Cavity – The interior chamber of a mold tooling that the molten plastic material is injected  into and solidified to create desired plastic product.

Core – A protrusion feature inside the mold tooling, which work with cavity to obtain the shape of plastic product.

Mould Base – It’s a supporting plate that the mold core and mold cavity are attached inside. On the other hand, mould based is used to clamp the whole mold on the injection machine when injection molding process.

Parting line – A divided line on a plastic product, which used to weld the mold cavity and mold core together.

Draft – It’s an angle or degree on the plastic products, which used to easier depart the plastic product from mold tooling.

Sprue – A round chamber that transfer plastic material from the nozzle through runner system in the mould tooling.

Ejection pin – It’s metal shaft/pin that push off the plastic products from the mould.

Vent – A small space in the mold between mold core and mold cavity. It allow pressure air that gave by injection machine to escape aside of mold, instead of staying at plastic product, and prevent injection molding defects to happen

Terms of Plastic Injection Molding Process

Injection molding – The injection molding process consists of an injection molding machine, raw plastic material, and a injection mold tooling. The plastic raw material is melted in the injection molding machine and then injected into the mold tooling, where it cools and solidifies into create the desired plastic products.

Gate – The channel to carry melted plastic material to flow into the mould tooling.

Shot Cycle – The total time that takes to complete a finished plastic product when injection molding process.

Shrinkage – The material reduction portion after the plastic product cools from mold tooling. Normally there will be a shrink mark on the surface a plastic product.

Deformation – When the final plastic product come out from injection machine, the product looks not straight obviously or measured by a certain equipment.

Flash – Additional material from desired shape or dimension

Flow marks – An outstanding pattern existing on the surface of plastic product, it normally result by slow injection speed.

Welding line – It’s also called the juncture line where normally happens on round feature that two flow fronts meet and are unable to join together during the injection molding process.

Over molding – It’s injection molding process to make a second time injection based on existing plastic workpiece. Normally it’s for soft material to over mold the hard material. Like TPU+PC, TPE+PC, PU+ABS, etc.

After seeing our shares about plastic injection mould and plastic injection molding process above, I think you should have some basic idea on those terms. Once you still are not clear about what those meaning, or you have any query, you can feel free to contact us for help.