Newcomers to the world of plastic injection moulding are often met with a whole new vocabulary that can seem quite confusing and intimidating at times. That’s why we’ve compiled this three-part post of some of the more common terms to help ease some of that uncertainty.

Welcome to Part 3 of our post, where we look at some of the remaining terms you should know.

Ejector Pin

A rod, pin or sleeve that pushes a moulded part off of a core or out of a moulding cavity.


This refers to the ability of a material to return to its original state when stretched.


The product or material delivered from an extruder, for example, film, pipe profiles, tubes etc.


The process of forming tubes or continuous shapes by pushing melted material through a die.


The process of manufacturing plastic products through various moulding and forming actions.


An additive to resins that improves its physical properties, such as creating impact resistance, hardness, dimensional stability etc., or to reduce the cost of the resin.


This refers to the secondary work such as, filing, deflashing, buffing, drilling etc., that needs to be completed on a moulded product before it is ready for use.


This refers to any excess plastic attached to the moulding along the parting line. This will have to be removed before the part is deemed acceptable.

Flow Rate

This refers to the volume of material passing a fixed point per unit time.

Missed a few terms? Check out Part 1 and 2 and stay glued to the blog as we bring you more injection moulding terms you should know in the future.

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