Marine anchors

Anchoring apparatus in the form of a marine anchor including a fluke member (3) and a load application point (26) on the marine anchor for attaching an anchor-line attachment-means (5), said marine anchor in operational configuration being an anchor for operation below the surface of a mooring bed (10) characterised in that a straight line containing said load application point (26) and the centroid (C) of the fluke member surface viewable from said load application point when the anchor is in operation forms a forward-opening centroid angle β with a forward direction F, in which direction said fluke member surface has a minimum projected area, said angle β being in the range 68° to 85° for operation of the anchor in soft cohesive soil and being in the range 50° to 65° for operation in non-cohesive soil whereby a pulling force applied to the anchor by the anchor line at the anchor-line attachment-means load application point (26), when the anchor fluke centroid (c) is buried at least twice the square root of said maximum projected area below the mooring bed surface causes the anchor (1, 23) to tend to move in the soil of the mooring bed (10) with a substantial component (9B) of displacement in said forward direction F.

Anchoring apparatus in the form of embedment means (13) for directly embedding a marine anchor, said embedment means (13) comprising an elongate follower member including means for driving the anchor into a mooring bed, means for detachable attachment to the marine anchor, and means for bending recoverably when subjected to transverse forces.

Anchoring apparatus in the form of embedment means (13) for directly embedding a marine anchor, said embedment means (13) comprising an elongate follower member adapted for detachable attachment to the marine anchor, characterised in that said follower member (13) is adapted to bend recoverably when subjected to transverse forces, said anchoring apparatus further including an anchor embedment means in the form of an elongate follower (13) having a bottom end adapted for the releasable attachment thereto of a marine anchor (1, 11, 23), said follower (13) serving to push the anchor (1, 11, 23) through a mooring bed (10) to a buried position in the bed, characterised in that the follower (13) includes means for supplying lubricating fluid for the provision of a layer of low friction substance on the anchoring apparatus, said lubricant supply means comprising piston-cylinder means (112, 113, 114) for providing reservoir means (115, 123) for providing lubricant, and delivery ducting (122, 131, 132, 134, 135) for the delivery of lubricant from the reservoir means (115, 123) for the provision of said low friction layer, lubricant delivery being achieved by relative movement between the piston and cylinder.

A method of deploying a drag embedment anchor (1) or direct embedment anchor (11) or drag anchor (23), comprising detachably attaching an elongate follower member (13) pivotably to the anchor (1, 11, 23) via a pivot (17) and pushing said anchor into a mooring bed (10) by the follower member(13) substantially in a direction of minimum projected area of the surface of a fluke member (3) of the anchor as viewed from a load application point (26) of an anchor line attachment means (5) attached to an anchor line (4) until a centroid (C) of the anchor fluke member (3) is at least twice the square root of the maximum projected area of the fluke member (3) below the surface of the mooring bed (10), and pulling on said anchor line (4) before detachment of the follower member (13) from the embedded anchor (1, 11, 23) so as to cause the fluke member (3) to rotate to an operational attitude in the soil of the mooring bed (10) by pivotal reaction with the follower (13).