Ice-resistant anode unit

Abstract

The utility model relates to means for the electrochemical protection of metal objects partially or completely submerged. In particular, to anode assemblies used in cathodic protection systems against corrosion of ship hulls and other floating objects using imposed current, intended for operation in extreme Arctic conditions. The ice-resistant anode assembly of the cathodic protection system against corrosion comprises a sequentially arranged backup plate, an insulating layer, an anode, and a protective plate attached to the backup plate with slots ensuring contact of the anode with water, wherein the anode and the plate are elliptical in shape. The technical result achieved through the implementation of the utility model consists in improving the performance characteristics of the anode assembly in an ice-resistant design. 3 c.p. phyl.; 2 fig.

Description

[0001] This utility model relates to means for the electrochemical protection of metal objects partially or completely submerged. Specifically, it relates to anode assemblies used in cathodic protection systems against corrosion of ship hulls and other floating objects using imposed current, designed for operation in extreme Arctic conditions.

[0002] Coating a ship's hull with special protective compounds cannot adequately protect it from corrosion, a problem particularly relevant for icebreakers operating in extreme Arctic conditions. The abrasive effects of ice significantly reduce the service life of coatings and accelerate hull corrosion. Installing cathodic protection systems using imposed current significantly reduces the corrosion rate, extending the life of the vessel and increasing the minimum allowable intervals between drydocking. Such systems include hull-mounted anode assemblies, reference electrodes for potential monitoring, and a control unit with a rectifier and a DC power source. Anode assemblies comprise a base (duplicate plate) welded to the underwater portion of the ship's hull's outer plating, an anode (the working element), and may also include a cofferdam.

[0003] Disc marine anodes made of titanium alloy with a galvanic protective coating, with a body (base) made of polymer material are known from the prior art [https: / / keeperanode.com / mmo-round-disc-anode-for-ship-cathodic-protection-system-circular-shape / ]. Cathelco marine anodes are also known [https: / / mnsspb.ru / wp-content / uploads / pdf / cath_sys.pdf?ysclid=moi7zz77oo910432581]. In one version, the anode is made of elliptical shape, the anode surface is made of platinized titanium or a mixture of metal oxides. Such anodes quickly fail under conditions of exposure to ice loads, since they are not protected from mechanical damage.

[0004] The anode unit for the cathodic protection system against marine corrosion of metal ships and structures is known according to the Russian Federation patent No. 92662, IPC C23F 13 / 06, published on March 27, 2010.According to the patent, an anode unit of a system for cathodic protection against marine corrosion of the hulls of metal vessels and structures, comprising a dielectric base with a groove made therein, into which a bimetallic anode plate with a current-carrying element is mounted, wherein the dielectric base is provided with a cladding layer of silicone rubber resistant to the effects of seawater electrolysis products, characterized in that an additional groove parallel to the first groove is made in the dielectric base, into which an additional anode bimetallic plate is mounted, electrically connected to the first bimetallic plate by means of a jumper, wherein the dielectric base is covered with a protective sheet made of titanium, in the protective sheet above the grooves in the dielectric base there are slots made, wherein the protective sheet is connected to the hull of the protected metal vessel or structure through a contact rod made of titanium and a chain of series-connected diodes.The working surface of the anode of this design has a small area of ​​contact with water, which reduces the efficiency of the cathodic protection system.

[0005] The closest in technical essence to the claimed device (prototype) is the design of an anode assembly with a disk anode, a hull-mounted icebreaker [https: / / pss.ru / ekhz-dlya-morya / ekhz-dlya-sudov / sistema-katodnoy-zashchity / anod-korpusnoy-ledovyy / ]. The anode is made of a titanium alloy with a platinum group oxide coating, protected by a slotted titanium plate and insulated from the cofferdam body. However, as is known, an elliptical shape, unlike a disk shape, improves current distribution, allows for the installation of anode assemblies on hulls with a complex profile, and provides lower hydrodynamic resistance.

[0006] The technical problem solved by implementing the utility model is the need to expand the arsenal of technical means intended for electrochemical corrosion protection systems for objects partially or completely under water, in particular, those operated in extreme Arctic conditions and subject to the mechanical effects of ice.

[0007] The technical result achieved by implementing the utility model consists of improving the performance characteristics of an ice-resistant anode assembly. The elliptical shape of the anode and protective plate primarily improves hydrodynamic characteristics and protective current distribution, and also allows for the installation of anode assemblies on housings with complex profiles.

[0008] The essence of the utility model is expressed in the following set of essential features: an ice-resistant anode assembly of a cathodic protection system against corrosion comprises a sequentially arranged backup plate, an insulating layer, an anode, and a protective plate attached to the backup plate with slots providing contact between the anode and water. The anode and plate are elliptical in shape. The anode assembly may also comprise a cofferdam connected to the backup plate. The protective plate may be made of metal or a polymer material and may contain more than two slots providing contact between the anode and water.

[0009] This combination of essential features improves hydrodynamic performance and protective current distribution, and allows for the installation of anode assemblies on hulls with complex profiles. The elliptical shape of the anode and, consequently, the plate, ensures a more uniform flow field in the water, reducing the size of dead zones and increasing the effectiveness of protection over large hull surfaces. Ellipses offer less resistance to flow, reducing fuel consumption and the risk of damage from contact with nets and ice. Ellipses are easier to install flush with the surface, minimizing protrusions on the sides, bottom, or propeller-rudder system with uneven contours, maintaining the hull's streamlined appearance.

[0010] Furthermore, in a preferred particular embodiment of the utility model, the anode assembly comprises a cofferdam connected to a backup plate. The presence of a cofferdam improves the performance characteristics of the anode assembly by facilitating its installation and maintenance.

[0011] Also, in a preferred particular example of the implementation of the utility model, the protective plate is made of metal or polymer material, contains a plurality (more than two) of slots that provide improved contact of the anode with water, which ensures better distribution of the protective current.

[0012] Fig. 1 and Fig. 2 show an example of the implementation of the utility model - an ice-resistant anode unit of a cathodic protection system against corrosion with a cofferdam, where:

[0013] 1 - Duplicate plate.

[0014] 2 - Anode.

[0015] 3 - Insulating layer.

[0016] 4 - Protective plate.

[0017] 5 - Cofferdam.

[0018] 6 - ​​Welded seam.

[0019] 7 - Slots.

[0020] In this embodiment of the utility model, the backup plate (mounting base) 1 is made of metal; during the installation of the anode unit, it is welded to the hull of a vessel or other floating object. An insulating layer 3 in the form of a special putty is applied to the surface of the recess of the outer part of the mounting base 1, isolating the anode 2 from the vessel hull. The anode 2, which can be made of a titanium alloy coated with oxides of platinum group metals or other mixed metal oxides, is placed in an isolated recess of the backup plate 1 and connected to the cathodic protection system through a central hole in the plate 1. A protective grid 4 made of metal or polymer with slots 7 is attached to the backup plate 1 using threaded connections along the perimeter of the plate, consisting of studs, nuts, washers, and, in order to reduce the influence of seawater, is closed with polymer threaded plugs.Before installation, the threaded plugs are filled with a sealing compound (mastic or grease). To remove excess sealing compound, the plugs have special drainage holes. When tightening the threaded connections, the protective plate presses the anode 2 against the backup plate. In this embodiment, the anode assembly is also equipped with a cofferdam 5, connected to the base 1 by a weld 6. The cofferdam contains a removable cover and a sealed cable entry; the interior of the cofferdam is typically filled with lithol.

Claims

1. An ice-resistant anode unit of a cathodic protection system against corrosion, comprising a sequentially arranged backup plate, an insulating layer, an anode, and a protective plate attached to the backup plate with slots that ensure contact of the anode with water, characterized in that the anode and plate are made elliptical in shape.

2. An ice-resistant anode unit of a cathodic protection system against corrosion according to paragraph 1, characterized in that the backup plate is connected to the cofferdam.

3. An ice-resistant anode unit of a cathodic protection system against corrosion according to paragraph 1, characterized in that the protective plate with slots is made of metal or a polymer material.

4. An ice-resistant anode unit of a cathodic protection system against corrosion according to paragraph 1, characterized in that the protective plate contains more than two slots that ensure contact of the anode with water.

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