DI Thomas Krivec and DI Gottfried Steiner holding the State Prize certificate The State Prize for consulting / engineering consulting seeks to identify and promote excellent, exportable solutions from the wide-ranging field of engineering achievements in Austria. From many candidates for the year 2009 the Engineering Office for Plastics Technologies of DI Gottfried Steiner (IB Steiner) won the prize in recognition of the development of Exjection technology.
What the Exjection process basically does in comparison to legacy injection moulding techniques is to move the mould insert that forms the section in sync with the injection movement at right angles to the machine's longitudinal axis. The motion of the mould creates a continuous free cavity volume that is continually filled by melt flowing into it. Thus, injection moulding of long, thin-walled, plastic sections of a defined length is no longer restricted by the fluidity of the plastic in a cooled mould, thanks to the Exjection process.
The fully electrical Engel e-motion injection moulding machine was chosen for developing this process. Besides the main machine movements, the mould insert is also driven synchronously with the injection movement by means of an electrical servomotor and a ball screw. Excellent platen parallelism and uniform distribution of compression over a given area, as provided by the e-motion clamping units in the mould area, not only avoid the burrs, but also ensure that very little force is required to move the mould insert when the clamping force has been built up. Engel developed an Exjection software tool to control machines using this new process. Initial serial machines have already been deployed on the market in the production of light facings and trims.
Thanks to the Exjection process, extremely long parts can be produced with a lower melt pressure and lower melt temperature compared to legacy approaches. The ability to use smaller injection moulding machines is typical of the Exjection process. Besides considerably improved energy efficiency, lower investment costs also mean a significant reduction in manufacturing costs.