Piggyback molding

A more affordable, more compact, and less complicated alternative to multimolding systems that use rotary tooling is what Cincinnati Milacron demonstrated at NPE. A 1100-ton model in its Maxima MG series of two-platen presses featured a secondary injection unit riding piggyback on top of the primary shooter. The secondary unit is directly mounted to the stationary platen via a sled, providing proper alignment. Automotive windows?fixed PC sidelights (2.15-lb shots) with black PC bezels (8.4 oz shots)?were molded and inmold-coined.

Just 427 inches long and 138.4 inches wide with 61-by-47.2 inches between the bars and capable of running molds weighing up to 44,620 lb and measuring up to 115 inches wide, the Maxima MG 1120 reportedly takes up to less than 20% the floorspace of machines of comparable tonnage. Piggybacking the injection units reduces the size of a machine that would be required to run this part in rotary tooling, while at the same time maintaining structural integrity of the stationary platen by eliminating the need for drilling two holes. The show machine also demonstrated magnetic-platen QMC and tierod pulling every hour.

Cincinnati Milacron, Cincinnati, OH
(513) 487-5000; plastics.milacron.com