Anchor Handling Winches
The winches deploying, recovering and repositioning anchors and mooring lines in subsea operations, rated in wire pull, and their testing regime under SOLAS.
An anchor handling winch is defined by SOLAS regulation II-1/2.31 as a winch for deploying, recovering and repositioning anchors and mooring lines in subsea operations. The definition excludes the anchor windlass that handles a ship’s own anchors, and it excludes mooring winches, so the equipment it captures sits almost entirely on anchor handling tug supply vessels and offshore construction ships.
The full article will cover the drivetrain and the control philosophy: the drum and its spooling gear, the brake and its holding capacity, render and recovery modes, the shark jaws and towing pins that work with the winch rather than as part of it, and the emergency release arrangements whose failure has featured in more than one capsize investigation.
It will treat the regulatory regime separately from that of lifting appliances, because the two diverge. An anchor handling winch is rated in wire pull rather than safe working load and is not required to be marked with one. Under the IMO guidelines in MSC.1/Circ.1662 it is operationally tested annually and at five-year intervals, and the Administration or a recognized organization witnesses the five-yearly test.