Anode Clamp Assembly and Use of Such Assembly

Abstract

An anode clamp assembly for attachment to a submerged structure is described. The anode is used for corrosion protection. The assembly comprises an elongate bar shaped or cylindrical anode arranged on a rod having rod ends extending from each end of the anode and clamps being attached to the rod ends. The assembly is easy to use and is suitable for being attached to a submerged structure by means of a Remote Operated Vehicle having a simple construction. Each clamp comprises two first legs having an intermediate bore arranged for rotation around a first rotation axis defined by the rod ends. Each of said first legs at a first end is provided with a griping jaw for attachment to a part connected to the structure and at a second end is hinged connected to a second leg via first hinges having a second rotation axis. The second legs are hinged to each other via a second hinge having a third rotation axis for forming an over-centre acting knee joint together with the two first legs. Said first rotation axis and said third rotation axis are arranged in a common plane being a symmetry plane for the clamp.

Claims

1. Anode clamp assembly for attachment to a submerged structure which is to be corrosion protected and comprising: an elongate bar shaped or cylindrical anode arranged on a rod having rod ends extending from each end of the anode, clamps being attached to the rod ends, wherein each clamp comprises two first legs having an intermediate bore arranged for rotation around a first rotation axis, each of said first legs at a first end is provided with a griping jaw, characterised in that said griping jaw is intended for attachment to a part connected to the structure, that each of said first legs at a second end is hinged connected to a second leg via first hinges having a second rotation axis, that the second legs are hinged to each other via a second hinge having a third rotation axis for forming an over-centre acting knee joint together with the two first legs, that said first rotation axis is defined by the rod ends and that said first rotation axis and said third rotation axis are arranged in a common plane being a symmetry plane for the clamp.

2. Assembly according to claim 1, wherein a stop is provided at a first of the second legs in form of an end portion extending past the second hinge in direction against the first rotation axis.

3. Assembly according to claim 2, wherein said first of the second legs is L-formed and that said stop is provided by the short part of the L-formed leg.

4. Assembly according to any preceding claim, wherein said rod is a hollow tube being closed in both ends.

5. Assembly according to any preceding claim, wherein said first legs comprise two leg parts being arranged under an angle being between 15 and 45 and wherein said bore is arranged at the connection between the two leg parts.

6. Assembly according to any preceding claim, wherein the anode is of aluminum and said rod is of steel.

7. Assembly according to any preceding claim, wherein the first and second legs are made of metal plates, preferable steel.

8. Assembly according to claim 7, wherein at least some of the legs are made of superposed metal plates between which the other legs made from one metal plate are arranged.

9. Assembly according to any preceding claim, wherein the clamp in the locked condition establish electrical and structural connection at the jaws and at the bores in the first legs.

10. Use of an assembly according to any preceding claim, wherein the griping jaws are connected to a rod acting as support for an anode and having rod ends extending from each end of the anode and acting as support for the anode and being attached to the structure.

Description

DESCRIPTION OF THE DRAWING

[0048] The invention will be explained in more detail with reference to the accompanying drawings, where

[0049] FIG. 1 is a principle sketch of an anode clamp assembly according to the present invention,

[0050] FIG. 2 illustrates a detail of the anode clamp assembly according to FIG. 1 seen in one direction.

[0051] FIG. 3 illustrates the detail as shown in FIG. 2 however, from another direction.

[0052] FIG. 4 illustrates the detail of FIGS. 2 and 3, however, from a third direction,

[0053] FIG. 5 illustrates a partial view of a jack-up leg/spud-can with anodes attached,

[0054] FIG. 6 illustrates different types of anodes casted around supporting steel bars, and

[0055] FIG. 7 illustrates typical anodes casted around tube for the support of the anode.

DETAILED DESCRIPTION OF THE INVENTION

[0056] FIG. 1 illustrates an anode clamp assembly 1 according to the present invention which is intended for attachment to a submerged structure 2 which is to be corrosion protected.

[0057] The anode clamp assembly 1 comprises an elongate bar shaped anode 3 arranged on a rod 4 having rod ends 5 extending from each end 6 of the anode 3 and being closed by an end cover 38. Clamps 7 are attached to the rod ends 5.

[0058] In FIG. 1 the anode 3 is a new anode to be attached. An existing anode 8 is illustrated. The existing anode has a steel bar 9 arranged with protruding end parts at each end of the anode 8, which steel bar 9 is used for the connection to the structure 2. In the present situation the attachment is established through welding. However, alternatively the steel bar 9 could be attached by bolting. The existing anode 8 is casted around the steel bar 9.

[0059] The anode 3 is provided with eyelets 10 which are intended for handling the anode with suitable tools for transport and attachment.

[0060] FIG. 2-4 more clearly illustrates the structure of the clamp 7.

[0061] As seen in FIG. 2 each clamp comprises two first legs 11,11. Each of the clamps has an intermediate bore 12 arranged in an intermediate position between the ends of the legs 11,11. The intermediate bore 12 is arranged for rotation around a first rotation axis 13 which is defined by the rod ends 5. A locking disc 37 is secured to the rod end 5 in order to maintain the two first legs 11,11 in their position. The locking disc 37 could be secured by any suitable means including welding.

[0062] Each of the first legs 11,11 is provided with a gripping jaw 14,14 for attachment to the steel bar 9. The gripping jaws 14,14 are arranged at a first end 15 of the first legs. At the second end 16 of the first legs second legs 17,17 are connected through a hinge 18,18. Each of the hinges 18,18 has a second rotation axis 19,19. The second legs 17,17 are hinged to each other through a hinge 20 which defines a third rotation axis 21. This construction forms an over-centre acting knee joint.

[0063] The first rotation axis 13 and the third rotation axis 21 are arranged in a common plane which extend in the vertical plane as seen in FIG. 2 and extend in the elongate direction of the anode 3. This common plane would also be a symmetry plane for the clamp 7.

[0064] The first 17 of the second legs are provided with a T-form. At one branch of the T an extension 22 is provided which constitutes a stop which is arranged in contact with the material 23 surrounding the bores 12. The other branch 24 of the beam of T-formed leg extends upwardly and is provided with a hole 25. This hole is intended for cooperation with the tool for activating and deactivating the clamp 7. As indicated with the double arrow 26 the force to be used for activating or deactivating the clamp 7 is extending in one direction. As a device for activating and deactivating the clamp could be a hydraulic cylinder (not shown) which is attached to the hole 25 and connected with a Remote Operated Vehicle which is also supporting the anode 3 through a grip in the eyelets 10.

[0065] It is noted that the leg 17 need only to have the L-form and that other construction could be used for activating or deactivating the clamp.

[0066] As seen more clearly in FIG. 3 the first legs 11,11 comprise two leg parts 28,29; 28,29 being arranged under an angle 27 being between 15 and 45. The bore 12 is arranged between the two leg parts. The two first leg parts 28,28 are arranged substantially parallel within the cross sections covered by anodes 3,8. The second leg parts 29,29 are arranged under a mutual angle 40 and between these two leg parts 29,29 the second legs 17,17 are arranged.

[0067] From FIG. 4 it occurs that the first leg 11 is made of two superposed metal plates 30 and it also occurs that the second leg 17 is made of two superposed metal plates 31. Furthermore, it occurs that the first leg 11 is made of one single metal plate 32, and that the second leg 17 is made of one single metal plate 33. Accordingly, the legs could be connected with each other in the manner illustrated in FIG. 4 and thereby have a rather limited extension.

[0068] The anode 3 is of aluminium and the rod is made of steel.

[0069] FIG. 5 illustrates a partial view of a jack-up leg 35 being provided with anodes 8.

[0070] FIGS. 6 and 7 illustrate different types of anodes. It occurs that the anodes are made of aluminium casted around a steel bar 9 or a tube 36. The steel bar or tube acts as a support for the anode 8 and it is typically attached to a structure by welding or bolting.

[0071] Other forms of the anodes are possible.