WO1990008204A1

WO1990008204A1 - Holder device for marine anodes

Info

Publication number: WO1990008204A1
Application number: PCT/DK1990/000006
Authority: WO
Inventors: Joergen Leon Hoegberg; Bent Grumstrup Soerensen
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-01-11
Filing date: 1990-01-09
Publication date: 1990-07-26
Anticipated expiration: 1991-07-11
Also published as: DK12989D0; EP0453486B1; AU4958290A; DE69018814T2; DK0453486T3; DE69018814D1; EP0453486A1

Abstract

A holder device for a marine anode (2) which is mounted to ship's cladding plates to prevent or reduce their corrosion, by connection to the ship's side (10) of protruding end parts (8) of anode carrier irons (6) preferably embedded in the anode (2), consists of a steel body (12) which is adapted to be welded onto the exterior of the ship's side (10), and which is shaped with a hollow (14) which is open to receive one of the said end parts (8) of the anode carrier iron (6), and in connection with the said hollow (14), the holder device includes clamping means (16) which are arranged to retain the said end part (8) and to establish an efficient conductive connection between the said end part of the anode carrier iron (6) and the ship's side (10). In this way it becomes possible to attain a substantial facilitation and reduction of cost in changing marine anodes, as the change can be made in a relatively short time by a diver without the ship needing to visit a yard or to be docked.

Description

Holder device for marine anodes

The present invention relates to a holder device for a marine anode which is mounted to ship's cladding plates to prevent or reduce their corrosion, by connection to the ship's side of protruding end parts of anode carrier irons preferably em¬ bedded in the anode.

With a view to preventing or reducing the galvanic corrosion of ship's cladding plates of metal, for example steel, it is known to mount specially shaped zinc anodes directly onto the ship's cladding plates with the purpose of protecting the steel plates and of concentrating the corrosive action on the anodes. Known zinc anodes are provided with embedded anode carrier irons comprising for bent iron slabs whose opposing end parts protrude from the zinc anode and which usually are flush with a side face thereof. Opposing parts of the anode carrier iron are intended to be welded directly onto the ship's cladding plates; or the anode carrier iron is possibly connected to the cladding plates by means of bolts which are welded onto the ship's side.

On larger ships a very large number of zinc anodes is used, for example 100 - 400 units. It goes without saying that the ship's zinc anodes must be changed at regular intervals. It is a very extensive and costly matter to change these anodes, and with larger ships the change of the anodes requires dock- ing, that is the ship must visit a yard. It must be mentioned that besides being corroded away as a result of galvanic cor¬ rosion, the anodes are also worn off which occurs in particu¬ lar when sailing in ice-filled waters. The layer of zinc oxi¬ de which is formed rather quickly on the surface of the anode and which shows that the anode works, is worn off again relatively quickly. Under normal conditions the anodes must be changed about once a year. It is not uncommon, however, that ships which sail in ice-filled waters must have changed the anodes a number of times a year. The purpose of the invention is to provide a holder device for marine anodes by means of which the work with changing the marine anodes can be substantially facilitated and made less costly .

The holder device according to the invention is distinctive in that it comprises a steel body which is adapted to be wel¬ ded onto the exterior of the ship's side, and which is shaped with a hollow which is open to receive one of the said end parts of the anode carrier iron, and in that, in connection with the said hollow, the holder device comprises clamping means which are arranged to retain the said end part and to establish an efficient conductive connection between the said end part of the anode carrier iron and the ship's side. In this way it becomes possible to attain a substantial facili- tation and reduction of cost in changing marine anodes, as the change can be made in a relatively short time by a diver without the ship needing to visit a yard or to be docked. The mounting itself of holder devices according to the invention possibly will require a docking of the ship; but then suc- ceeding changes can be made by a diver, possibly in a number of rounds, for example if a ferry in regular service is con¬ cerned. A very substantial advantage in the anode holder de¬ vice according to the invention is that one can avoid always having to remove the old anode carrier irons by flame cut- ting, that is, one avoids creating cutting scars in the clad¬ ding plates of the ship. For the very reason of avoiding such cutting scars in the ship's side one has up to now often cho¬ sen to let the old anode carrier irons remain in place on the ship's side, which is inappropriate as it is desirable that below the water line, the ship's side should be as smooth as possible.

With a view to facilitating the change work as much as pos¬ sible, the holder device according to the invention is prefe¬ rably arranged such that at one side of the steel body which is intended to be placed against the ships's side, the said hollow corresponds with a top side edge and an end edge, fac- ing the anode, of the steel body, and in that the hollow is formed with a funneled shape, as opposite of the said end ed¬ ge the hollow is formed with a side face which slopes down¬ ward from the said top side edge towards a preferably hori- 5 zontal limiting edge, and as opposing the side of the steel body which is intended to be placed against the ship's side, the hollow slopes downward/inward at least on a partial stretch from the said top side edge and down to the horizon¬ tal limiting edge.

10 In a simple way the holder device according to the invention can be arranged such that the said clamping means comprise a sturdy pointed screw which can be tightened, via a threaded bore from the front side of the steel body, against an end part of an anode carrier iron placed in the said hollow.

15 And with a view towards protecting the anode and diverting forces exerted for example by ice in the water, the holder device according to the invention can advantageously be sha¬ ped such that opposite the end edge which faces the anode, the steel body is shaped with a side face sloping in ward to-

20 ward the side of the steel body which is intended to be pla¬ ced against the ship's side.

In the following the invention will be more closely explained with reference to the drawing, wherein:-

Fig . 1 is a perspective view or illustrating a known way of 25 mounting an anode directly on the ship's side,

Fig. 2 is a corresponding perspective view of an embodiment of anode holder devices according to the invention, for example for mounting the anode shown in Fig. 1 on a ship's side, and

30 Fig. 3 is a perspective view of an anode holder device accor¬ ding to the invention, cf. Fig. 2. Fig. 1 shows a marine anode 2 as is known, consisting of an anode body 4 of zinc or of an alloy mainly of zinc wherein an anode carrier iron 6 consisting of a form-bent iron slab is mounted by embedding it in such a way that protruding end 5^"parts 8 of the anode carrier iron 6 are flush with the back side of the marine anode 2, such that the latter can be moun¬ ted closely to a ship's side 10 by welding the end parts 8 onto it. The marine anode 2 as shown is intended for mounting on a straight side part of a vessel; but also curved marine 10 anodes are known for mounting on curved surfaces of ships.

Instead of welding it directly onto the ship's side 10, the marine anode 2 shown in Fig. 1 can - as shown in Fig. 2 be mounted in anode holders 12 which are welded onto the ship's side 10 beforehand at correct mutual distances. The anode

15 holders 12 are formed from steel and arranged to be welded onto the ship's side 10 with a sturdy circumferential weld - except for a corner area of the holder 12 where a hollow 14 is provided for receiving one of the end parts 8 of the anode carrier iron 6. The hollows 14 in the respective anode hol-

20 ders 12 are open upwardly along the ship's side 10, that is to say that it is quite easy to place the marine anode 2 in the holders 12 before the end parts 8 are efficiently clamped to the ship's side 10 and the anode holders 12, respectively, by means of sturdy pointed screws 16, such that an efficient

25 conductive connection is established between the ship's side 10 and the marine anode 2.

As shown in Fig. 3 the hollow 14 is double funnel-shaped as an end face 18 opposite the marine anode 2 slopes down from an upper side edge 20 from which a longitudinal surface part 30 22 slopes down as well, the surface part 22 passing into a face 24 which runs in parallel with a base surface 26 of the anode, that is also in parallel with the ship's side 10.

The anode holder 12 can be opened and closed by means of a sturdy hexagonal spanner as the sturdy pointed screw 16 is

35 preferably an UNBRAC0 pointed screw with a cutting edge. Finally it should be mentioned that the anode holder accord¬ ing to the invention is adapted for known marine anodes. In the future it is expected, however, that marine anodes for different purposes may advantageously be adapted to anode ^"holders according to the invention.

Claims

C A I M S :

1. A holder device for a marine anode which is mounted to ship's cladding plates to prevent or reduce their corrosion, by connection to the ship's side (10) of protruding end parts (8) of anode carrier irons (6) preferably embedded in the anode (2), c h a r a c t e r i z e d in that the holder device comprises a steel body (12) which is adapted to be welded onto the exterior of the ship's side (10), and which is shaped with a hollow (14) which is open to receive one of the said end parts (8) of the anode carrier iron (6), and in that, in connection with the said hollow (14), the holder de¬ vice comprises clamping means (16) which are arranged to retain the said end part (8) and to establish an efficient conductive connection between the said end part of the anode carrier iron (6) and the ship's side (10).

2. A holder device according to claim 1, c a r a c t e ¬ r i z e d in that, at one side of the steel body (12) which is intended to be placed against the ships's side (10), the said hollow (14) corresponds with a top side edge (20) and an end edge, facing the anode (2), of the steel body (12), and in that the hollow (14) is formed with a funneled shape, as opposite of the said end edge the hollow is formed with a si¬ de face (18) which slopes downward from the said top side ed¬ ge (2) towards a preferably horizontal limiting edge, and as opposing the side of the steel body which is intended to be placed against the ship's side (10), the hollow (14) slopes downward/ inward at least on a partial stretch from the said top side edge (20) and down to the horizontal limiting edge.

3. A holder device according to claim 1, c h a r a c t e - r i z e d in that the said clamping means comprise a sturdy pointed screw (16) which can be tightened, via a threaded bo¬ re (17) from the front side of the steel body, against an end part (8) of an anode carrier iron (6) placed in the said hol¬ low.

4. A holder device according to claim 1, c h a r a c t e ¬ r i z e d in that opposite the end edge which faces the ano¬ de (2), the hollow (14) is shaped with a sloping side face (18) and an upper, longitudinal sloping face (22).