| 摘要 |
PURPOSE:To eliminate breaking of wire during wire drawing and to stabilize wire drawing work and product quality by specifying slanting angle of the first slanting face of inlet side of the wire rod to be worked and the adjoining second slanting face, reduction of area, and the relation between the reduction of area and slanting angle of the second slanting face. CONSTITUTION:A thick Al covered steel wire is passed from the mouth part 1 of a die through the first and the second slanting faces 2, 3 and the bearing part 4 and pulled out to the back relief part 5 and drawn. At this time, liquid lubricating oil is applied near the mouth part 1. It is pressurized by faces 2, 3 and pressure becomes maximum in the bearing part 4, and an oil film sufficient for lubricating drawing is formed. For this purpose, slanting angles alpha, beta of faces 2, 3 are regulated to <=5 deg. and about <=18 deg. respectively, reduction of area gamma per one pass is regulated to about <=30%. Selection is made within allowable values in which angle beta and ratio gamma are inversely proportional. That is, drawing is performed in a sound area beta designated by a line A in the figure. |
