MALE DIE FOR MANUFACTURING MULTIHOLE EXTRUSION BILLET HAVING PLURAL HOLLOWS IN BILLET'S INSIDE AND OUTSIDE

摘要

PURPOSE:To shorten a male die length and to reduce the total weight of a die by making the 1st male die an insert type inserted into a through hole of the 2nd male die. CONSTITUTION:The 1st male die 30 and the 2nd male die 40 are fixed and integrated by inserting the 1st male die 30 into the reduction part of a through hole 42 of the 2nd male die 40 from an end side. The top surface of a supporting wall 33 of the die 30 abuts on the inside wall of the hole 42 of the die 40 and is supported by the inside wall strongly and the front edge of the wall 33 abuts on the back bulgy part of a projection 43 for formation of the 2nd hollow part and is positioned. A projection 32 of the die 30 for formation of the 1st hollow part is located at the position in the formation opening surrounded by a projection 43 of the 2nd male die 40 and the position of the projection 32 is separated from the projection 43. An extrusion hole 50 having a prescribed clearance is formed between bearings of those projections for formation of the 1st and 2nd hollow parts.