Heavy load lifting system - transports column sections along gantry for securing in place in succession

摘要

The system is partic. for the erection of travelling portal cranes in shipyards and avoids the need for erection towers etc. The columns of the portal are divided into sections of equal height, and after the lowest section on each side, has been temporarily secured to the foundation and the travelling bogies attached to it, the gantry is placed over both with the remaining sections on top of it. A special truck running on rails on the top of the gantry then transports the sections one by one to the ends of it, where they are held in position above the previous ones and secured to them, typically by welding. The gantry is raised in stages by climbing mechanisms, and finally secured to the topmost sections at each end, after which the temporary column foundation sections can be removed, using the climbing mechanism.