A hoisting system for a drilling rig, which has a crown block for attaching to a derrick, the crown block comprising a plurality of sheaves; a travelling block suspended from the crown block via a hoisting cable, the travelling block comprising a plurality of sheaves and being connectable with a payload, the travelling block being arranged to move along a workpath; the hoisting system further comprising: a floating block comprising a plurality of sheaves reeved on the hoisting cable; wherein the floating block is configured to move between: a first arrangement in which the floating block is fixed relative to the crown block; and a second arrangement in which the floating block is fixed relative to the travelling block; wherein the hoisting system is arranged such that, when the floating block is in one of the first or second arrangement, the sheaves of the floating block overlap a sheave of the crown block or travelling block in a direction of the workpath.
Drilling rig hoisting system
2022-05-24
Patent
Electronic Resource
English
Drilling slag collecting box, hoisting structure and hoisting method
European Patent Office | 2023
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