GUSMER
Innovative processing method for PA 6 GF / Rapid tooling plus RIM -“ProDotyping”
US polyurethane-machinery manufacturers, Gusmer (Lakewood, New Jersey, USA; www.gusmer.com), have presented a completely new approach to prototype and series production for high-quality parts in glass-fibre reinforced PA 6. The process, operated under licence from Compcast Technologies (Barnegat Light, New Jersey) – inventor Matti Holtzberg´s company – involves rapid tooling (RTP) coupled with the reactive injection moulding of PA 6. Since the RIM process gets by without the high pressures required for standard injection moulding, moulds produced by RPT can be used both for producing technically identical prototypes and for high-volume production running into several million articles, says Gusmer.
Using data from a design drawing, it is possible to produce moulds from different materials in a very short time today. “ProDotyping” now exploits the possibility of polymerising PA 6 directly from caprolactam in the RPT mould, with the aid of a catalyst. Up to 50% glass fibre is also added during the liquid phase so as to give the standard level of stability in the product. The PA 6 crosslinks inside the mould in just a few seconds, and the finished part (which Gusmer claims has identical mechanical properties to the injection moulded part), can then be demoulded. Since RPT permits the same mould to be produced several times over on a cost-efficient basis, the process can be run with up to 30 moulds, thus permitting semi-continuous operation. This matches the productivity of the standard injection moulding process.
The advantages of this process for creating functional prototypes and very small series are readily apparent, as is the speeding up of the “time to market”. Gusmer claims that the benefits go even further than this, however. Moulds are up to 90% cheaper than for standard injection moulding, while the machinery is only about one third of the price. With production runs of up to 100,000, the cost per item is considerably lower than for standard injection moulding. And even for series of up to 2 million, costs can still be up to 50% lower.
Using data from a design drawing, it is possible to produce moulds from different materials in a very short time today. “ProDotyping” now exploits the possibility of polymerising PA 6 directly from caprolactam in the RPT mould, with the aid of a catalyst. Up to 50% glass fibre is also added during the liquid phase so as to give the standard level of stability in the product. The PA 6 crosslinks inside the mould in just a few seconds, and the finished part (which Gusmer claims has identical mechanical properties to the injection moulded part), can then be demoulded. Since RPT permits the same mould to be produced several times over on a cost-efficient basis, the process can be run with up to 30 moulds, thus permitting semi-continuous operation. This matches the productivity of the standard injection moulding process.
The advantages of this process for creating functional prototypes and very small series are readily apparent, as is the speeding up of the “time to market”. Gusmer claims that the benefits go even further than this, however. Moulds are up to 90% cheaper than for standard injection moulding, while the machinery is only about one third of the price. With production runs of up to 100,000, the cost per item is considerably lower than for standard injection moulding. And even for series of up to 2 million, costs can still be up to 50% lower.
06.02.2003 Plasteurope.com [15073]
Published on 06.02.2003