摘要 |
1,126,142. Jointing by tube expanding. W. BUSCH. 19 Jan., 1967 [24 Jan., 1966], No. 2916/67. Heading B3J. In expanding a tube into an orifice by a tubeexpander with skewed rollers and a mandrel driven by a prime mover, the direction of rotation of the prime mover is reversed automatically for a selectable period upon the prime mover reaching a torque appropriate to the desired engagement between the tube and orifice, after which period the prime mover is again switched automatically to its original direction of rotation and the expander moved along the tube to expand a different section. The period of reverse running may vary between 0-1 and 10 seconds, and due to the skewed rollers the mandrel withdraws slightly. A stop may limit penetration of the expander into the tube. |