| 摘要 |
PURPOSE:To form a tilted elbow without welding flanges thereto by holding the inside circumferences of the flange parts formed by forging at both ends of a straight pipe in the mouth cores of sliders, pressing the straight blank pipe part with a punch and bending the same to a prescribed shape. CONSTITUTION:Flanges are formed by forging at both ends of a straight blank pipe, and the flange parts are fitted to the partial annular grooves of both sliders 13. Mouth cores 14 are inserted into the inside circumferences of the flange parts and are positioned by means of nuts 14b. A punch 2 is attached to the bottom surface of a pressing means 1 and a center pin 3b is fitted into both pin holes. When a pressing force is exerted on the means 1 to move downward said means, both main guide levers 6, 7 expand the top end of a slider 10 while moving slightly the same up into a guide 9. Auxiliary guide levers 11, 12 are guided by sloped grooves 4b, 5b so as to incline outward, and both die guides 4, 5 are turned around the center pins 4b', 5b' to expand the bottom ends thereof, by which the straight pipe is formed into an elbow. |
