Can All-Electrics Cut It in High-Speed Packaging?
How about four PP ice cream cups with IML in 2.2 sec?
A number of injection molding machine builders are betting that the answer is Yes. If you’re looking for evidence to answer that question for yourself, consider this demonstration at last month’s Plástico Brasil 2019 show in São Paulo. A 160-metric-ton all-electric Engel e-motion press molded thin-wall PP ice-cream cups in four cavities with IML in 2.2 sec. Total shot weight was 14.8 g. The machine boasts injection speeds up to 500 mm/sec. Credit for the extremely fast cycles also goes to Beck Automation of Switzerland, which provided the IML automation.
Though it’s not easy to find an apples-to-apples comparison with a hydraulic machine, Arburg demonstrated four-cavity molding of PP tubs with IML in 1.95 sec at NPE2018. The shot size was quite similar (each tub weighed 3.4 g). The press was an Allrounder 570 H (200 m.t.) with an electric clamp unit and hydraulic accumulator injection unit. IML automation came from Brink B.V. of the Netherlands.
Both Arburg and Engel will talk about what’s required for a high-speed, thin-wall packaging machine at the Molding 2019 Conference in Indianapolis, March 19-21.
Modifications to the common core pin can be a simple solution, but don’t expect all resins to behave the same. Gas assist is also worth a try.
Most molders work with two parameters for establishing second-stage pressure. But within Scientific Molding there are actually four.
Weld or knit lines are perhaps the most common and difficult injection molding defect to eliminate.