Patent ID: 9056751
Filing Date: 2015-06-16
Classification: B66C,B66D,E21B

Abstract:
1. A hoisting device comprising: a hoisting cable; a winch; an elevated crown block comprising multiple crown block sheaves having an essentially horizontally extending rotation shaft; wherein the crown block has a length defined by its longitudinal axis, and wherein the multiple crown block sheaves are arranged such that a first set of multiple crown block sheaves having a rotation shaft essentially perpendicular to the longitudinal axis of the crown block is positioned in the middle of the crown block, which first set is symmetrically flanked by a second and third set of multiple crown block sheaves having a rotation shaft essentially parallel to the longitudinal axis of the crown block, and a traveling bottom block comprising multiple traveling bottom block sheaves having an essentially horizontally extending rotation shaft, the traveling bottom block being provided with a load attachment device, wherein the traveling bottom block has a length defined by its longitudinal axis, which is essentially parallel to the longitudinal axis of the crown block, and wherein the traveling bottom block sheaves are arranged such that a first set of multiple traveling bottom block sheaves having a rotation shaft essentially perpendicular to the longitudinal axis of the traveling block is positioned in the middle of the traveling bottom block, above the load attachment device, which first set is symmetrically flanked by a second and third set of multiple traveling bottom block sheaves having a rotation shaft essentially parallel to the longitudinal axis of the traveling block, about which crown block sheaves and traveling bottom block sheaves the hoisting cable is reeved, wherein at least some of the traveling bottom block sheaves are associated with a releasable connector, and are thereby detachable from the load attachment device and displaceable to an inoperative position while the hoisting cable remains reeved about these displaceable traveling bottom block sheaves, wherein in the inoperative position the displaceable traveling bottom block sheave is locked directly via the releasable connector of the traveling bottom block sheave to a crown block sheave, which inoperative position is located adjacent to the crown block.