Gravity installed anchor

Abstract

An anchor for mooring of structures to a water bottom, comprising an elongated central body having a longitudinal axis through its center. The central body comprises a plurality of channel members radiating outward from the center, each with a channel therein. A plurality of nose and tail plates are disposed within the channels, and hingedly connected to the central body, so that the plates can be swung in or out from the central body, and thereafter fixed in place (for example, by pins inserted through mating holes in the channel members and plates). A means for attaching a mooring line to the anchor, for example a load ring encircling the central body and rotatable completely around the circumference of the central body, has an arm hingedly attached thereto. The arm can be rotated to a desired angle with respect to the longitudinal axis of the central body, and fixed at a set angle or within a range of angles to the longitudinal axis.

Description

CROSS REFERENCE TO RELATED APPLICATIONS [0001] This regular patent application claims priority to provisional patent application titled “Gravity Installed Anchor,” inventor Evan H. Zimmerman, filed Nov. 11, 2004.BACKGROUND [0002] 1. Field of the Invention [0003] This invention relates to apparatus used in the mooring of structures to the soils underlying bodies of water, referred to as waterbottoms. More specifically, this invention relates to a type of anchor particularly, although not exclusively, suitable for so-called “gravity installation,” where the anchor is released at a desired height above a water bottom and allowed to fall to and penetrate into the waterbottom. [0004] 2. Description of Related Art [0005] Different types of anchors, especially suited for the mooring of floating structures, have long been in use. Some anchors rely on their weight for holding capacity. Others have flukes which tend to drive the anchor into the waterbottom when a tension is applied to a moori...

AI Technical Summary

Benefits of technology

[0007] In addition, mooring line attachment points to such anchor designs are limited to top (that is, the uppermost end) or fixed side attachments. Top attachments do not require any particular alignment with the mooring line direction since the pull can be from any direction; however, the top attachment greatly reduces holding capacity. Side attachments yield greater holding capacity, however current designs require accurate attachment point orientation (that is, the attachment point must be aligned with the direction of mooring line pull). Angular alignment of the side attachment point with the mooring line pull can be difficult to achieve in field applications. The present invention preferably comprises a mooring line attachment which can rotate completely around the body of the anchor, and further comprises a hinged arm, eliminating problems related to installation orientation. Further, the arm reduces the likelihood of the mooring line being caught on the anchor plates. Yet another advantage of the present invention is that a single anchor can be adjusted to vary the exposed nose and tail plate areas, thereby rendering the anchor suitable for various applications, soil types, or soil strength gradients.

[0008] The anchor of the present invention, in a presently preferred embodiment, comprises an elongated central body having a longitudinal axis through its center. The central body comprises a plurality of channel members radiating outward from the center, each with a channel therein. A plurality of nose and tail plates are disposed within the channels, and hingedly connected to the central body, so that the plates can be rotated in or out from the central body, and thereafter fixed in place (for example, by pins inserted through mating holes in the channel members and plates). A means for attaching a mooring line to the anchor, for example a load ring assembly comprising a load ring encircling the central body and rotatable completely around the circumference of the central body, has a bracket thereon and an arm hingedly attached thereto. The arm can be rotated to a desired angle with respect to the longitudinal axis of the central body, and fixed in a set angle or within a range of angles to the longitudinal axis.

Problems solved by technology

One disadvantage of the prior art gravity-installed anchor designs is that a significant amount of penetration into the soil is required for adequate holding capacity.

In addition, mooring line attachment points to such anchor designs are limited to top (that is, the uppermost end) or fixed side attachments.

Top attachments do not require any particular alignment with the mooring line direction since the pull can be from any direction; however, the top attachment greatly reduces holding capacity.

Angular alignment of the side attachment point with the mooring line pull can be difficult to achieve in field applications.

Further, the arm reduces the likelihood of the mooring line being caught on the anchor plates.

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