METHOD FOR MAKING BOLTS WITH HIGH NECK

摘要

FIELD: plastic metal working, namely forming stepped rod-type fastening parts such as bolts with high neck. SUBSTANCE: rod-type blank with solid cross section is placed in sizing hole of lower die-half and in hexagonal recess of upper die-half. In bottom portion of said hexagonal recess there is sizing groove for fixing end of blank. Die-halves are drawn together to form hexagonal head and neck of bolt. Said neck is formed by two stages. At first stage hexagonal head and neck with diameter equal to that of bolt head are formed. At second stage said neck portion is upset for forming final-dimension neck. EFFECT: enhanced efficiency. 4 dwgr