Novel Hot-Runner Technology Borrows From Flat-Die Extrusion

At this month’s K 2016 show in Dusseldorf, Austrian moldmaker Haidlmair will introduce a new hot-runner technology that combines the know-how of its injection moldmaking business with that of its extrusion flat-die business, called EMO. The new FDU (Flat Die Unit) technology is an open hot-runner nozzle system in which the nozzle is flat, with a long, narrow slit opening, somewhat like an extrusion flat die. The plastic thereby flows evenly into the cavity through a long, narrow gap. This is said to reduce shear in the nozzle by up to half, which reduces melt heating. In some materials, such as PP, lower injection pressure can be used, the company says, and a broader process window and shorter cycle times are said to result, as well. FDU technology will be demonstrated at the Milacron booth in production of a “miniature wrinkle box” derived from a distinctive Haidlmair design seen at previous shows. Stork of the Netherlands will mold a standard meat box with FDUs. And Wittmann Battenfeld will use FDU to mold a “soft wrinkle bag” from TPE (photo), the latest member of the “wrinkle box” family and a world premiere. Haidlmair’s North American plant is in Concord, Ont.