摘要 |
A tube coil of austenitic or ferritic material is bent into a coil with a steep pitch by clamping the end of the tube section to be bent in clamps located at the ends of two radial arms of the bending apparatus. One arm is then pulled away from the other arm to cause the clamped ends to displace relative to each other while a steeper pitch is imparted. The pulled arm is free to rotate while the clamps are free to pivot in planes tangential to the tube coils. In one embodiment, the clamps can also move radially of the supporting arm. |