Full size image available through contact
Many people think the most useful use of a cool gas in a product is as a key part of fizzy drinks but researchers at the University of Warwick's Warwick Manufacturing Group have found that that cool gases also prove amazingly useful if injected into plastics.
Ordinary gas assisted injection moulding (GAIM) methods have been used by plastic manufacturers to reduce the weight of plastic products, or to increase the rate at which components can be made by using the gas to displace volumes of unnecessary hot plastic from the plastic component's core. However despite using gas to speed the cooling process when producing injected moulded plastics, few people had ever considered what extra benefit could be achieved by actually cooling the gas itself before adding it to the plastic.
The Warwick researchers developed a new process which they have dubbed "Kool Gas" which uses a cryogenic heat exchanger to cool the high pressure nitrogen gas to temperatures as low as -150oC before it is injected in to the plastic part. The results were dramatic - Kool Gas allowed the plastics parts to cool and form 40% faster than by normal methods meaning plastic manufacturers could produce individual components this way 40% faster than by current methods or produce 40% more product in the same time frame as before. No detrimental effect was observed in the moulded product and, in fact hollow components produced by this process provided a more controllable wall thickness ensuring consistent quality.