SCREW FOR LIGHT ALLOY INJECTION MOLDING MACHINE

摘要

PROBLEM TO BE SOLVED: To provide a screw by which the injection speed and the injection pressure are made higher in a light alloy injection molding. SOLUTION: From the tip end part of the screw body 20, a male screw forming part 20a forming the male screw on the outer peripheral part, a ring fitting part 20b fitable to a back flow preventive ring 18 and a seal annular part 20c having the front surface preventing the back flow of molten metal by abutting on the back surface of the back flow preventive ring 18 are respectively formed in order. A screw cap 14 having a female screw forming part 14a forming the internal screw on the inner peripheral surface, is screwed to the tip end part of the screw body 20 by screwing this female forming part 14a thereof to the male forming part 20a.