SU1571874A1 - Method for pressing-out of hollow stepped products with flanges head and shank - Google Patents

Abstract

FIELD: plastic metal working; applicable in manufacture of products having deep stepped hollows and stepped external surface, for instance, bodies of spark-plugs. SUBSTANCE: cylindrical blank with diameter equalling the diameter of cylindrical head 2 under the flange of spark-plug body is transferred to stamping position of automatic machine. On this position, rolled-in shoulder on one end of blank is formed and hollow in end face is marked. Then, blank is moved to the following position so that deformed end with hollow in the end face proves to be facing the deforming punch. In this step, hollow 5 is formed by combined pressing out with subsequent formation of rolled-in shoulder 3, hexahedral flange 6, cylindrical head 7 and material is taken for subsequent pressing-out of shank 8. To form rolled-in shoulder and flange, use is made of piercing punch with movable bushing whose cross-section corresponds precisely to annular clearance between wall of die hollow, where flange is formed, and piercing punch, and end face follows the shape of external surface of rolled-in shoulder and flange end face adjacent to it. In the following step, hollows in shank are made by broaching from both sides and leaving thin partition of definite geometry. Then, partition is removed by punching, and shank is finally formed. To produce annular shoulder between hollows, removed is only central part of partition. Shoulder 3 is rolled-in and hollow 4 is marked simultaneously for one shape-forming step or successively by two process steps depending on the characteristics of the used equipment. EFFECT: higher quality of manufactured product and extended technological capabilities due to reduced technological efforts. 10 dwg