Polymer specialist Rehau is basing its lightweight construction research efforts on the high pressure mixing and metering systems from KraussMaffei in the form of a Rimstar Compact 8/4 HP-RTM.

KraussMaffei
High-pressure injection using the RimStar series enables the processing of fast-reacting resin systems. This makes it possible to quickly fill the mould for fibre-reinforced components to the benefit of shorter cycle times.
At the new technical centre for lightweight construction in Viechtach, special hydrogen pressure tanks are being developed as highly secure reservoirs, meeting a key requirement for the future use of state-of-the-art fuel cell technology.
Short cycle times support series production
The specific defining features of the KraussMaffei RimStar series mixing and metering systems are their flexibility and high product quality with low scrap rates. One example of where these advantages shine is in conjunction with HP-RTM (high pressure resin transfer moulding) processes.
Steffen Bauer, Sales Manager for Reaction Process Machinery in Germany at KraussMaffei, explained: "High-pressure injection using the RimStar series enables the processing of fast-reacting resin systems. This makes it possible to quickly fill the mould for fibre-reinforced components to the benefit of shorter cycle times."
Rehau is using the process at its Viechtach location to research new methods for developing thick-walled hollow components in lightweight design, such as hydrogen pressure tanks for vehicle manufacturing. The goal is to achieve process control capable of supporting large-scale series production for these kinds of components. Collaboration with KraussMaffei began back in the prototype development phase. As a result, initial component tests regarding the mould concept and high pressure resin transfer moulding technology in the technical centre for lightweight construction took place at KraussMaffei's facilities. The results this provided were successively integrated into on-going development and formed the basis for the design of the high pressure RTM system for Rehau's new technical centre for lightweight construction.
Perfect premixing
Rehau's RimStar-Compact 8/4 HP-RTM is equipped with a MJH 10P-2KVHM mixing head. This ensures perfect premixing of resin and hardener and works according to the self-cleaning principle. Release-agent metering at the mixing head, including the corresponding release agent station, complete the efficient mixing head system. Systems with demanding processing temperature requirements can be metered to perfection with RimStar high pressure RTM metering machines. High-pressure engineering ensures that the components are thoroughly mixed in the mixing head.
Investment in the future
The technology developed in-house at Rehau for manufacturing hydrogen tanks is to transition from the laboratory to production scale at the Viechtach production location. To accomplish this goal, the company invested €3.4 million (£2.4 million) in special systems engineering within the plant.
"This decision is a significant step towards the future for us—to drive the development of new technologies and to make an important contribution to maintaining job security at the plant location," said Martin Wippermann, Member of the Executive Board for Rehau Automotive. "Our customers demand that we lead the way with new ideas and efficient solutions, that we support them in engineering mobility fit for the future, that we develop environmentally friendly systems that reduce resource usage and grow those systems to support series production for the market."

KraussMaffei
Advancing the idea of lightweight construction together: Martin Wippermann, Member of the Executive Board for Automotive, Vice-President Dr. Veit Wagner and Stefan Tetek, Viechtach 11 plant manager, during the opening of Rehau's new technical centre.