Improvement of sea anchor

Abstract

A marine anchoring arrangement is described wherein a marine anchor (1, 23) is drivingly embedded vertically into a mooring bed (10) by an elongate follower (13), especially by its own weight and that of the follower. The follower (13) has a bottom clevis part (103) adapted to hold detachably the anchor (1) via the anchor shank (2) by means of a fulcrum pin (17) whereby the anchor (1) may swing relative to the bottom part (103). For initial penetration, the anchor (1) is held in a position of minimum forward resistance, specifically with the forward direction F of the fluke (3) parallel to the follower axis (20) and this is achieved by a shear pin (109) between the anchor (1) and the bottom part (103). When the anchor (1) is embedded to a preferred depth (d) specifically at least twice the square root of the maximum projected fluke area (as viewed normal to direction F), the anchor (23) is moved to a position for anchor setting by pulling on an attached anchor cable (4 / 4A) so causing the shear pin (109) to fracture and the anchor (23) to rotate about the fulcrum axis until arrested by a stop (21) on the follower (13). The follower (13) can then be pulled clear and recovered. The above anchoring arrangement provides a considerably improved anchoring performance in comparison with existing direct embedment arrangements.

Description

technical field [0001] The present invention relates to sea anchors, and more particularly to drag embedding and direct embedding anchors and their embedding devices. Background technique [0002] Sea anchors buried in the anchored seabed are usually tied to anchor lines in order to connect with objects that will be moored in the water above the anchored seafloor. The anchor includes a load application point and an anchor claw, and the anchor cable is installed on the load application point by an anchor cable installation device (such as an anchor chain link); the anchor also includes a plane of symmetry, which includes a first direction and a second direction (positive direction) ) F, in the first direction, when the anchor is working, the surface of the anchor claw member has the largest projected area when viewed from the point of application of the load, and in the second direction (F), the projected area of ​​the surface is the smallest . Therefore, in these two direc...

AI Technical Summary

Problems solved by technology

[0007] These anchors have the following disadvantages: floating anchors require a horizontal displacement component to achieve a suitable burial depth below the anchored seabed surface, and this horizontal displacement component is sometimes unacceptable; the problem with direct buried anchors is that The burial depth gradually decreases when overloaded, which eventually leads to sudden failure due to breaking out of the anchored seabed

Also, direct burial anchors require a longer pile feeder to be pushed into the seabed, which would be easily damaged and difficult to handle when placed on the deck of the anchored vessel

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