| 摘要 |
Disclosed is a metal pipe forming apparatus for continuously bending a metal plate having a constant width in the lengthwise direction, and which can be used in the continuous manufacture of metal pipes, and in which roll arrangement is optimized to minimize the number of rolls and maximize a forming force. The disclosed metal pipe forming apparatus includes an auxiliary bending roll (2) disposed on the outer surface of the pipe to be produced from a metal plate and a main bending roll (3) disposed on the inner surface of the pipe. The main bending roll has a diameter smaller than that of the auxiliary bending roll, and has a large contact angle with the metal plate to exert a large forming force, and changes the contact angle thereof in accordance with the relative position of each roll to adjust the forming force. The main bending roll can be designed to exert the full forming force thereof even if the diameter thereof increases, thus easily overcoming the problem of shaft drooping. The present invention can be designed to readily correspond to the material, thickness, and diameter of the targeted metal pipe. The metal plate, which is bent in a lengthwise direction by the auxiliary bending roll and the main bending roll of the apparatus of the present invention, is subsequently squeezed by a squeeze roll and readily formed into a pipe. |
