Christian Pum, president of Engel Holding and responsible for marketing and sales at the injection molding machine maker (Schwertberg, Austria), says Engel has lined up its first (as yet unidentified) customer for its new Dolphin units, which were introduced at a May symposium. "Since the May symposium we''ve made a steady stream of presentations on Dolphin-mostly in Europe but also in North America," he said during an interview with MPW on August 31 at Engel headquarters.
The Dolphin development is a new process technology initially targeting molding of dashboards or interior trim that consist of solid structural parts and a soft skin. The structural component is molded from polypropylene (PP), which is coated with special foamable polyester. Engel worked with material suppliers BASF (PP), P-Group/Italy (foamable polyester), and a Swiss moldmaker on the Dolphin technology.
The machine used for the Dolphin process is a two-component large-capacity Engel Duo Combi M with 15,000 kN clamping force. It includes two horizontally opposed injection units and a double-daylight mold with a rotating block that carries the mold cores. With a 180-degree rotation, the PP-base part is transferred into the overmolding station for application of the polyester layer. The polyester melt integrates nitrogen as a nonchemical blowing agent. The nitrogen is added in the plasticizing unit and homogenized by the screw, helping form a microcellular bubble structure and a soft-touch skin.