Gas Assist injection moulding technologies

The gas assist injection moulding theories:

• After mould closing, the plastic is injected to fill or nearly fill the mould cavity.
• After a selected time delay, first phase is gas injected.
• Second phase gas penetration to compensate for volumetric shrinkage of the plastic as it cools.
• A uniform gas pressure is applied throughout the plastic.
• Gas is exhausted to atmosphere or for recovery before mould opens.
• Plastic refill commences after the nozzle valve is closed or after the plastic feed gate has solidified.

Gas Assist injection moulding typical applications:

• The gas flows into the path of least resistance in the thicker sections where the plastic interior is still in a molten state.
• Gas Assist injection moulding is normally applicable for components in which there are thick and thin sections.

Gas Assist injection moulding advantages

• Elimination of sink marks.
• Avoidance of plastic packing from the moulding machine.
• Reduced in-mould pressures by up to 60%, and therefore reduced press lock forces enabling larger
• The use of the gas injection moulding as a means of transmitting pressure uniformly throughout the moulding.
• mouldings on much smaller machines.
• Reduced power consumption.
• Reduced moulded in stress, and therefore improved dimensional stability with no distortion.