Anchor Swivels Improve your Anchoring All Round
Understand options for using stainless steel anchor swivels between anchor and chain to improve anchoring for sailing boats and yachts.
Why use an anchor swivel when anchoring your sailing boat? How might it help you and what options do you have?
Simply put, an anchor swivel attached to a marine anchor allows the anchor chain to move independently of the boat anchor itself. This allows 360 degrees freedom of movement of the galvanised anchor chain or stainless steel anchor chain, and can help in both keeping the anchor set, and with retrieval, especially after a long time at anchor when the sailing boat or yacht might have spun around the anchor due to currents or tidal flow.
Picture the scene when, after some time, the boat has made several rotations around the anchor chain due to the ebb and flow of the tide. On your anchor alarm app, this will be shown as circles around the anchoring point. Now imagine staying at anchor overnight, when we really want the anchor to stay put - what is happening to that chain with all those rotations?
Two things may happen as a result of the rotations on an anchor chain: Without an anchor swivel, the anchor chain will be putting more and more pressure on the anchor shank to rotate also, and in doing so, the anchor might be becoming more and more dislodged and unset. This is because as the anchor is rotated, the set will have to be broken as the whole body gets dragged out of the sea bed. If the anchor is very well set, all this rotational force is being absorbed into the shank, with clear bending potential. Secondly, once the anchor is to be retrieved, many rotations in the chain will have an effect on the ability to use the windlass to work properly. See here for anchoring gear mentioned in this article. The rotations in the chain will cause the anchor chain to jump in the windlass gypsy and so stop the retrieval.
Even if the sailing boat is not actually performing circles around the anchor, with each tide, the anchor chain will be retracing its path over and over the anchor, each pass of the anchor chain over the anchor may leave kinks or rotations in the chain, or at the very lease, put pressure on a traditional shackle that might be securing the chain to the anchor shank. See here for traditional toughened anchor shackles available online, UK.
So for the solution: Using an anchor swivel like those available here as the Mantus Swivel or here as the Ultra Flip Swivel, will allow the chain full freedom to rotate as required. this will reduce the loads placed on the anchor chain, the anchor shank, and the anchor windlass, thus reducing all loads in the system, and prolonging the life of all components of the anchoring setup. Additionally, as the anchor is raised off the seabed, the chain will quickly untangle itself and become completely straight, due to the swivel doing its work. As the anchor reaches the bow roller, if the anchor comes up backwards, the swivel will allow the anchor to fall right side up, thus allowing it to return correctly to the stowed roller position. This 'flip' is what makes the Ultra Flip Swivel so good, in that it will not allow the anchor to return to the boat upside down. It will always make the anchor flip right side up.
Here at Pro Marine Store, we work with Mantus and Ultra to bring their excellent anchor swivels to the UK market, available in all sizes online today. call us to discuss the options, and choose the swivel right for your boat application. Additionally, see this excellent video made by our friends on Sailing Yacht Fair Isle, on the Ultra anchor and Ultra Flip Swivel.