Spirex Corp., Youngstown, Ohio, is broadening the application range of Twinshot technology, which uses a special screw and barrel to convert a standard single-barrel injection press for coinjection.

Spirex Corp., Youngstown, Ohio, is broadening the application range of Twinshot technology, which uses a special screw and barrel to convert a standard single-barrel injection press for coinjection. Twinshot uses a special screw and barrel that plasticate two materials separately. Spirex is now developing a TwinShot screw, along with a new heat/cool zone in the barrel, that will allow processing rigid PVC without burning or degradation. Also, Twinshot is being considered for use with valve gating in multicavity tools. Spirex says there are more than 100 commercial applications in the U.S., mostly for smaller parts, but the technology is now being applied to larger parts on presses up to 2000 tons.