Corrosion protection using a sacrificial anode
AssigneeVector Corrosion Technologies Ltd.
InventorsGeorge Sergi, Attanayake Mudiyanselage Gamini Seneviratne, David Whitmore
Life of this patent
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Abstract
Corrosion protection of steel in concrete is provided by locating an anode assembly including both a sacrificial anode and an impressed current anode in contact with the concrete and providing an impressed current from a power supply to the anode. The impressed current anode forms a perforated sleeve surrounding a rod of the sacrificial anode material with an activated ionically-conductive filler material between. The system can be used without the power supply in sacrificial mode or when the power supply is connected, the impressed current anode can be powered to provide an impressed current system and/or to recharge the sacrificial anode from sacrificial anode corrosion products.
Claims41
A method for corrosion protection of a metal section in a cast body of an ionically conductive concrete or mortar material comprising:
- providing an anode assembly comprising:
- an impressed current anode;
- and
- a sacrificial anode of a material which is less noble than the metal section;
- maintaining the impressed current anode electrically separated from the sacrificial anode to prevent direct electrical communication therebetween;
- prior to installation, positioning the impressed current anode and the sacrificial anode into an assembly, wherein the impressed current anode and the sacrificial anode are fixed at relative positions in the assembly;
- installing the assembly, while the impressed current anode and said sacrificial anode are at said fixed positions, in contact with the cast body of ionically conductive concrete or mortar material so as to locate the impressed current anode in ionic contact with the cast body of ionically conductive concrete or mortar material and so as to locate the sacrificial anode in ionic contact with the cast body of ionically conductive concrete or mortar material;
- providing a DC power supply having a first pole and a second pole;
- the assembly including electrical connecting components connected to the impressed current anode and the sacrificial anode;
- and providing corrosion protection to the metal section by:
- providing a connection by the electrical connecting components of the first pole of the DC power supply to the impressed current anode;
- providing a connection of the second pole of the DC power supply to the metal section;
- and
- providing a connection of the sacrificial anode to the metal section;
- so that the impressed current anode by current from the DC power supply provides the corrosion protection of the metal section;
- and when the DC power supply is not present a current between the metal section and the sacrificial anode provides the corrosion protection of the metal section.
An anode apparatus for cathodically protecting a metal section in an ionically conductive material, the anode apparatus comprising:
- a sacrificial anode of a material which is less noble than the metal section;
- an impressed current anode with a DC power supply connected thereto;
- the DC power supply is a battery and is included with the sacrificial anode and the impressed current anode comprising common components of a common preassembled unit forming the anode apparatus;
- the impressed current anode and the sacrificial anode being electrically separated to prevent electrical communication therebetween;
- an electrical connection to the sacrificial anode;
- and an electrical connection to the impressed current anode.
An anode apparatus for cathodically protecting a metal section in an ionically conductive material, the anode apparatus comprising:
- a sacrificial anode of a material which is less noble than the metal section;
- an impressed current anode with a DC power supply connected thereto;
- the impressed current anode and the sacrificial anode being electrically separated to prevent electrical communication therebetween;
- an electrical connection to the sacrificial anode;
- and an electrical connection to the impressed current anode;
- an ionically conductive filler material;
- the DC power supply is a battery and is included with the sacrificial anode and the impressed current anode comprising common components of a common pre-assembled unit forming the anode apparatus;
- wherein the common pre-assembled unit is at least partly surrounded by the ionically conductive filler material.
An anode apparatus for cathodically protecting a metal section in an ionically conductive material, the anode apparatus comprising:
- a sacrificial anode of a material which is less noble than the metal section;
- an impressed current anode with a DC power supply connected thereto;
- the impressed current anode and the sacrificial anode being electrically separated to prevent electrical communication therebetween;
- an electrical connection to the sacrificial anode;
- and an electrical connection to the impressed current anode;
- an ionically conductive filler material;
- wherein at least the sacrificial anode and the impressed current anode comprise common components of a common pre-assembled unit;
- and wherein at least the common preassembled unit comprising the sacrificial anode and the impressed current anode is surrounded by the ionically conductive filler material.
Dependencies are inferred from the claim text.