The plastic injection moulding process produces large numbers of parts of high quality with great accuracy, very quickly.
Plastic material in the form of granules is melted until soft enough to be injected under pressure to fill a mould. The result is that the shape is exactly copied. Once the plastic moulding has cooled sufficiently to harden the mould opens releasing the part. The whole injection moulding process then repeats.
Inject Molten Plastic
INJECTION – the molten plastic that has been melted from pellet form in the barrel of the moulding machine (see next section) is injected under pressure into the mould.
Hold Mould Closed
DWELLING – after the molten plastic has been injected into the mould pressure is applied to ensure all cavities are filled.
COOLING – the plastic parts are then allowed to solidify in the mould.
Open Mould and Eject Part
OPENING – the moving platen moves away from the fixed platen (see next section) separating the mould tool.
The length of time from closing the mould to ejecting the finished plastic moulding is the cycle.