A hoisting tool (18 fig.1a) for upending a load (12 fig.1a), such as a monopile has a pull-in system 72 and a pay-out system 72 acting respectively on variable-length upper link 24 and lower 26 link connecting the tool to upper and lower sides of the load. The pull-in/pay-out system has respective drum portions 72A, 72B, on which the upper link and the lower link are wound respectively, possibly in mutually opposed circumferential directions. The drum portions rotate together to pull in the upper link and to pay out the upper link simultaneously, counterbalancing torque applied to the drum portions by tension in the upper and lower links to reduce aggregate torque required to control rotation of the drum portions. The hoisting tool may have a winch (58 fig.2a) to act on reeving wire (60 fig.2a) to alter the angle of upper and lower frame members (46, 48 fig.2a).
Upending elongate structures offshore
2025-01-08
Patent
Electronic Resource
English