Austrian injection moulding machinery maker Engel has developed a two-component injection moulding system to reduce cycled times for the production of housing parts for medical devices.
“The key thing with housing parts is the cooling time,” said Dr. Georg Steinbichler, SVP of research & development for technologies at Engel Austria.
As the wall thickness cannot be decreased for stability reasons, conventional one-component production leaves no opportunity to reduce the cycle time.
However, in the two-component process, Engel injects two thin layers, each of which quickly cools.
“Since both injection moulding steps are carried out at the same time, overall production efficiency increases,” added Steinbichler.
The company has used a Hack Formenbau 8-cavity Vario Spinstack mould on the cleanroom version of its all-electric e-motion 310H/170W/160 combi injection moulding machine to achieve “very short” cycle times.
The machine is equipped with a vertical indexing shaft with four positions: the first for injection moulding the bodies, using a transparent polypropylene from Borealis; the second for cooling; the third for applying a second layer of polypropylene to the pre-moulded parts; and the fourth for a viper 20 speed robot remove the parts.
The linear robot reaches down to remove the eight housing parts from the closed mould to make the cycle time even shorter.
The two-component process also allows for adding a sight glass to the opaque housing as it is being injection moulded.
The fully servoelecric two-component precision mould is the first to feature Engel’s newly developed software programme.
“With the software’s help, it makes no difference to machine operators whether the mould is hydraulically or servoelectrically operated,” said Dr. Gerhard Dimmler, SVP of product research and development at Engel Austria.
The user can programme the servoelectric movements without the need for additional qualifications, according to Dimmler.
Servoelectric moulds are more precise compared to hydraulic systems and allow for completely oil-free production when combined with all-electric injection moulding machines.
The solution also features Engel compact cell which helps lower the production unit’s footprint.
For fully automated operation, the cell includes the box changer into which the viper speed robot deposits the injection moulded parts.
Engel will be demonstrating the process at K 2019, 16 to 23 Oct, in Düsseldorf, Germany.