An active heave compensation device has a framework 1 supporting a rotatable armature 3. This may be driven by a plurality of electrical motors 2 which may engage with the circumference of the armature via spur gears and cause a slewing action. Rotatable sheaves 5 may be located diametrically opposite each other on the armature. A wire rope or cable 6 may be passed over a first guide pulley, around the sheaves 5 and then exits the device via a second guide pulley 7. In use the armature rotates causing the sheaves to pull the cable into a tortuous path (Fig 1). The device damps out shock loading on the cable and may be used in a marine environment with the device located between a main lifting winch (Fig 2, 9) and a crane or derrick. A motion reference instrument (Fig 2, 14) measures movement of the vessel and acts to control the electric motors. The device also reduces cyclic bending stresses of the rope or cable. The device may rotate in the vertical or horizontal planes.
Active heave compensation apparatus
2017-10-25
Patent
Electronic Resource
English
IPC: | B66C Krane , CRANES |
HEAVE COMPENSATION TOOL, HEAVE COMPENSATION SYSTEM, AND HEAVE COMPENSATION METHOD
European Patent Office | 2025
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