A strategic alliance recently announced by Bayer AG and fellow German company Innova, may soon be improving the cost-efficiency, productivity and quality of injection moulding operations all over the world.
Central to the alliance is Innova’s new CONTURA technology, which is said to cut injection moulding times by around one third.
According to Reiner Westhoff of Innova Engineering ‘the biggest cost factors in injection moulding: machinery and labour costs are dependent primarily on the cooling time of the part in the mold’. Indeed, it’s estimated that around one third of the cycle time involved in producing a moulding is taken up with cooling it.
Add to this the fact that conventional cooling methods fail to create an even temperature distribution, often leading to warping and deformation, and its easy to see why this can be such a costly process. Contura enables accurate conformal cooling of injection moulding tools.
The first step is to examine temperature distribution in the part to be moulded in order to identify areas where cooling is poor – known as hot spots. On the basis of this analysis, Innova’s engineers determine the cooling behaviour of the mold. With the aid of CAE calculations they then construct the mould from individual ‘slices’ that are bonded together using high-temperature vacuum brazing, a technology borrowed from aeronautical engineering. The cooling channels are milled in such a way that they follow the contours of the part exactly.
The result is optimum heat removal from even the most inaccessible parts of the molding, leading to a reduction in cycle time and an increase in machine capacity. At the same time, quality is improved, with even cooling preventing warping and reducing stress in the part and differences in surface gloss. Innova claims that the savings achieved in machine, labour and materials costs are so great that CONTURA pays for itself within a year.