| 摘要 |
PURPOSE:To save time for arrangements between processes and to improve productivity by using the same roller having tip radius of specified dimension in spinning forming method that performs drawing, ironing and cutting on a blank pipe. CONSTITUTION:An end of a blank pipe 11 having t1 thickness is held by a collet chuck and rotated in a body with a mandrel 13 inserted into it. In drawing stage, plural rollers 14 are sent in the directions shown by arrows 16 and 17 at the same time to draw the pipe 11 to tapered form. Said drawing is repeated plural times, and a small diameter part along the mandrel 13 is formed. In ironing stage, the same roller 15 with the rollers 14 in the drawing process is used. After sending in the direction of arrow 21 by a specified amount, it is sent in the direction of arrow 22. A thin part having t2 thickness is formed by performing ironing of specified draft. Further, the roller 15 is sent in the direction of arrow 25 and cut to obtain a tubular member. The tip diameter R of rollers 14, 15 is made t1>R>t2. |
