Augustin, Germany – Hennecke has developed Variocast technology to reduce the cycle times of high- pressure RTM polyurethane processes.
The company says that this is a stepwise development of its existing Streamline technology and “meets the demands of users in the field of series production.” Variocast technology can be added to new Streamline machines or retrofitted to existing machines. Metering machines can use technology developed on complex flexible foam formulations but which has been adopted for use in Resin Transfer Moulding (RTM) processes.
Typically a Streamline machine will feature: density-independent flow-metering, component temperature control up to 130C and good materials management systems, says Hennecke.
Hennecke said unlike its standard Streamline machines, Variocast technology uses a separate stream made up of additives and accelerators. These can be injected at specific point in the cycle to help reduce moulding time.
Injection would typically happen just as t pre-heated liquid reactants had just wet the reinforcement. Injecting additives at this point in the cycle would allow good wetting, good cure and ensure that the components are consistent. This gives shorter cycle times than injecting components that are fully formulated and start reacting as they are injected, said Hennecke.