| 摘要 |
<p>The assembly system is suitable for application to pylons carrying overhead electric current supply lines. Prefabricated parts of the pylon are assembled in a continuous sequence from the top downwards. At each stage the lower piece, being fitted to the completed one above, is mounted on a vertically movable working platform, which is raised by the length of the piece when this has been connected to the one above. The pylon is then fixed in its height setting, while the platform is lowered to accommodate the next piece, the process being repeated over the whole length of the pylon until it is fixed to its base corner-pieces. There can be four or more power-driven uprights for raising the platform, with a locking top frame, and two or more cranes.</p> |
