| 摘要 |
PURPOSE:To work two tapered tubes at the same time with a simple sealing structure or a metal die shape by having at the center part after bulging so that the center part in the axial direction of a tube is made in the maximum diameter and both ends in smaller diameters. CONSTITUTION:The metal die 1 of tapered shape toward both ends having the center part in axial direction with the maximum diameter is fastened and a semi-finished tube is obtd. with bulging by placing the axial force by a pressure lot 2 with placing an inner pressure by the water pressure which is from a water pipe 3. Since two tapered tubes are obtd. by cutting the tube of semi-finished article and the smaller diameter part is positioned at the shaft end of the metal die 1, so the seal structure and metal die shape are simplified. |
