Abstract:
It is described a metal anode for cathodic protection in form of mesh ribbon having meshes whose holes are of rhomboidal shape, characterised by having such holes of rhomboidal shape arranged with the major diagonal oriented along the direction of the ribbon length and by the fact that the side edges along the ribbon length are free from cutting protrusions. It is also described a method for obtaining such anode.
Abstract:
A method of using and a steel reinforced concrete protector in an anode cavity which comprises a cored hole, a drilled hole or a cut chase formed in concrete. The protector comprises a sacrificial anode assembly and a separate backfill. The sacrificial anode assembly comprises a sacrificial metal element that is a metal less noble than steel and an activator to maintain an activity of the sacrificial metal element. The at least one spacer prevents the sacrificial metal element and the activator from contacting the surface of the anode cavity. The spacer and the sacrificial metal element have a coupling mechanism which facilitates connection of the sacrificial metal element to the spacer. The backfill is a pliable and viscous material which contains an electrolyte, and the backfill facilitates embedding the anode assembly in the anode cavity. The invention also relates to a prepackaged sacrificial anode assembly and a method of increasing a shelf life of the sacrificial anode.
Abstract:
Cathodic 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.
Abstract:
The cathodic protection of a reinforced concrete structure utilizes sacrificial anodes such as aluminum or zinc as well as alloys thereof. Each anode is embedded or substantially covered in a material consisting of a hydrophilic non-cementious open-cell foam. An activating agent such as one or more lithium salts is contained within the cells of the foam to maintain the anodes in an electrochemically active state. The activating agent may be immobilized in the cells using an aqueous gel such as agar. One or more metallic conductors electrically connect the anodes to the metal reinforcing members.
Abstract:
Cathodic 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.
Abstract:
Electrolytic protection of steel-reinforced concrete bodies such as bridges and building facades is achieved with carbon material inserted into the concrete body. The carbon material is connected to act as a anode with the steel reinforcement as a cathode, so that corrosive chloride ions migrate away from the steel reinforcement. The carbon material is inserted so as also to act as a reinforcement. In one arrangement carbon textile material is provided between inner and outer grout-filled plastics ducts fixed around post-tensioned steel cables. In another arrangement a carbon rod, or pin, is fixed between a concrete body and a steel I-beam.
Abstract:
An anode and backfill steel protector combination for inserting into at least one cavity which is mechanically formed in steel reinforced concrete. The anode and the backfill steel protector combination comprises an anode for insertion into the at least one cavity with the anode comprising a sacrificial metal element less noble than steel and a backfill which comprises a viscous and pliable ionically conductive material for insertion into the at least one cavity. The backfill is packaged within a cartridge and the cartridge is a cartridge for use with a cartridge which facilitates injecting the backfill from the cartridge into the at least cavity formed in the concrete. The backfill in a cartridge has a shelf life of at least 2 days.
Abstract:
An electric field modifier for boosting current output of a sacrificial anode for reinforced concrete to enhance its protective effect and direct the current output in a preferred direction to improve current distribution in galvanic protection of steel exposed to air. The combination comprises a sacrificial anode and an electric field modifier and an ionically conductive filler embedded in a cavity and the sacrificial anode is directly connected to the steel. The modifier comprises an element with an anode side supporting an oxidation reaction in electronic contact with a cathode side supporting a reduction reaction. The cathode of the modifier may form a cell with the sacrificial anode and is separated therefrom by the filler. The filler contains an electrolyte that connects the sacrificial anode to the cathode of the modifier. The reduction reaction on the cathode of the modifier may substantially comprise the reduction of oxygen from the air.
Abstract:
An electrolytic mortar for fabricating galvanic anode panels is strengthened with fibers to improve green strength and resistance to cracking. Elongated reinforcing fibers are introduced into a flowing stream of mortar and deposited in multiple layers upon a platen or mold. A sacrificial zinc anode of open construction is embedded between the multiple layers to allow for electrolytic conduction between the layers and over all surfaces of the zinc anode.
Abstract:
The installation and use of embedded sacrificial anodes to protect reinforced concrete may be improved. In one example a cavity [2] is formed in the concrete [3] and a puttylike backfill [4] is placed in the cavity and a compact discrete anode comprising a sacrificial metal element [1] is inserted into the backfill and a space is provided into which the backfill may move when subjected to a pressure arising from the formation of voluminous sacrificial meal corrosion products and a high current is passed from the anode to the steel in the concrete to arrest steel corrosion and activate the anode in the backfill. The space may be provided by venting the backfill to space outside the cavity through an opening [5] or by including a void space within the backfill [6] or a void space within the cavity [7].