Abstract: A carrier pipe is protected from corrosion by being received inside a casing at a location above ground. The casing, which can be formed from a polymer, defines a gap extending around an exterior surface of the carrier pipe. In one embodiment, the gap is substantially filled with a potting material having a corrosion-resistant property. In another embodiment, a self-contained impressed current cathodic protection system is received in the gap. A pull head is installed on the carrier pipe and/or casing for pulling the pipe assembly, including carrier pipe, casing, and elements received in the gap, into an underground bore as a single unit. In some embodiments multiple pipe assemblies are pulled together into the same bore.

Abstract: A carrier pipe is protected from corrosion by being received inside a casing at a location above ground. The casing, which can be formed from a polymer, defines a gap extending around an exterior surface of the carrier pipe. In one embodiment, the gap is substantially filled with a potting material having a corrosion-resistant property. In another embodiment, a self-contained impressed current cathodic protection system is received in the gap. A pull head is installed on the carrier pipe and/or casing for pulling the pipe assembly, including carrier pipe, casing, and elements received in the gap, into an underground bore as a single unit. In some embodiments multiple pipe assemblies are pulled together into the same bore.

Abstract: A carrier pipe is protected from corrosion by being received inside a casing at a location above ground. The casing, which can be formed from a polymer, defines a gap extending around an exterior surface of the carrier pipe. In one embodiment, the gap is substantially filled with a potting material having a corrosion-resistant property. In another embodiment, a self-contained impressed current cathodic protection system is received in the gap. A pull head is installed on the carrier pipe and/or casing for pulling the pipe assembly, including carrier pipe, casing, and elements received in the gap, into an underground bore as a single unit. In some embodiments multiple pipe assemblies are pulled together into the same bore.

Abstract: In an embodiment, an impressed current cathodic protection system includes at least one parallel-charge, serial-discharge supercapacitor bank to increase the duty cycle of the system. In another embodiment, the output of the parallel-charge, serial-discharge supercapacitor bank is applied to an anode using pulse width modulation to apply the correct amount of current to maintain a mesh potential at a desired value. In yet another embodiment, an impressed current cathodic protection system includes a microcomputer controller configured to maximize efficiency of the system.

Abstract: A carrier pipe is protected from corrosion by being received inside a casing at a location above ground. The casing, which can be formed from a polymer, defines a gap extending around an exterior surface of the carrier pipe. In one embodiment, the gap is substantially filled with a potting material having a corrosion-resistant property. In another embodiment, a self-contained impressed current cathodic protection system is received in the gap. A pull head is installed on the carrier pipe and/or casing for pulling the pipe assembly, including carrier pipe, casing, and elements received in the gap, into an underground bore as a single unit. In some embodiments multiple pipe assemblies are pulled together into the same bore.

Abstract: An alloy for a sacrificial anode according to a first preferred aspect of the present invention includes about 10% to about 50% of Zn, about 0.03% to about 0.6% of In, and about 0.0005% to about 0.05% of Zr. The balance may be Al and any unavoidable impurities. An alloy according to a second preferred aspect of the present application includes about 10% to about 50% of Zn, about 0.03% to about 0.6% of In, and about 0.05% to about 0.3% of Si. The balance may be Al and any unavoidable impurities. An alloy according to a third preferred aspect of the present invention includes about 10% to about 50% of Zn, about 0.03% to about 0.6% of In, and about 0.02% to about 0.2% of Ce. The balance may be Al and any unavoidable impurities. An alloy according to a fourth preferred aspect of the present invention includes about 10% to about 50% of Zn, about 0.03% to about 0.6% of In, about 0.005% to about 0.1% of Ti, and about 0.001% to about 0.02% of B. The balance may be Al and any unavoidable impurities.

Abstract: A preassembled cathodic protection system is provided for protecting buried structures such as guy anchors, which includes a reference cell, test station and anode, all prewired together and tested before delivery and field installation. The package includes a convenient connection for the structure which has one lead to an exposed stud or contact point on the test station, and another lead from the connection to the anode or anodes through a shunt in the form of a calibrated resistance wire. The shunt is connected to two spaced studs or contact points on the test station by which the shunt is read. The reference cell is also connected to a stud or contact point on the test station. The reference cell-test station lead extends through a flexible tube. The studs or contact points are on the dome or cap of a rigid tube designed to project out of the ground or an electrolyte a short distance. With a guy anchor the tube may include an elow and angled portion.

Abstract: An integrated cell and the test station is disclosed in a unitary package which includes internally encapsulated wiring connections at both the cell and test station. The cell and test station are tethered together by a flexible bungee tube which can be coiled and which can elongate or contract. The flexible tube provides a variable length and wide lateral flexibility. The tube also provides a convenient means to encapsulate the connections at both the cell and test station. The cell has a unique core formed by a double junction ceramic capsule. A pure copper coil element is positioned in the capsule in a super saturated solution of copper sulphate, for example. The capsule is sealed and the coil or element is electrically connected to a lead extending through the tube, and the end of the tube is encapsulated sealing the connection. The capsule is joined to one end of the bungee tube and the entire end is embedded in a stabilized hygroscopic gel which contains additional salt crystals.

Abstract: An anode and bracket assembly for attaching sacrificial anodes to submerged structures utilizes one or more shepard's hook hanger brackets. The anode or anodes are cast directly on the bracket with a relatively deep spiral grooved profile for vortex shedding in high currents reducing vibration of the anode, bracket and structure. The hooks extend vertically and have a crook or notch designed to mate with a horizontal structural member which may be circular or rectangular. The hook has a long approach or tip and a lifting eye on top to assist in the quick placement of the bracket on the structure. A pointed contact bolt is mounted in the hook to be driven into the underside of the structure. This clamps the bracket to the structure and also provides good electrical contact between the structure and anode. The anode may extend horizontally spanning between two or more hooks or simply hang vertically from a single hook.

Abstract: An anode and mounting bracket assembly is designed to seat quickly and easily on cylindrical or tubular underwater structures. The anodes span between end plates which include notches or recesses in which the tubular structure seats. The recesses include bell-mouth openings for ease of positioning. Each plate includes a pivoting gate including a saddle receiving the structure. Each plate also includes pointed bolts aimed over-center the gate pivots. When the brackets are positioned on the tubular structure the gates swing to a closed or locked position, the tightening of the bolts locks the gates closed. In such locked over-center position the gates block the bell-mouth openings of the plate recesses. The pointed bolts provide good electrical contact and the assembly may be easily removed by loosening the bolts to clear the gates. The assembly is then pulled from the structure.

Abstract: A solid high silicon cast iron elongated anode has a midpoint electrical connection keeping the connection as far as possible from the ends to combat the deleterious pencil effect. The anode is made by casting using a hollow or shell core to form a small axial hole extending from one end. The sand or foundry material of the core is removed and the wall of the hole at the blind end of the hole is at least partially finished to receive a diagonally split slug to which a lead wire is connected. Alternatively the hole is formed by a steel pipe which is left in place as a hole liner. The pipe may be supported by one or more chaplets. The slug is fastened in the blind end of the hole by a driving tool rotating a threaded headed bolt with both axial and rotational force to hold the connection in the blind end of the hole as it is secured in place. The hole is filled with a potting compound sealing the connection in the center of the solid cast iron anode.

Abstract: A continuous length anode is formed of relatively small valve metal wire having a electrocatalytic coating braided into a highly flexible ribbon. The wire may be copper cored. The valve metal is preferably titanium, although tantalum or niobium are also preferred. The coating is preferably a mixed metal oxide coating. The braid is formed from wire sizes of from about 1/16 or less to about 1/8" in diameter and the braided ribbon may be about 0.1 to about 6" inches wide. Four system applications are disclosed, two for steel reinforced concrete, one for a tank bottom, and one for a buried pipe. The braided anode may be used in combination with valve metal ribbon or bar and may readily be electrically connected to power feeds or to itself by spot weld or crimp connections. Power feeds may be connected at a butt end or anywhere along the length of the braid.

Abstract: An electrode is disclosed which is particularly useful as a reference electrode in cathodic protection systems. In any reference electrode or half cell, its continued stability is predominantly dependent on the metal ion concentration around it. In time such ions tend to leach away reducing the stability, effectiveness and life of the electrode. With the present invention such ions in the electrolyte may be replenished by the addition of a concentrated solution of metal salt to a ceramic canister which may include a glaze coating which may have one or more diffusion ports permitting the metal salt solution to leach at a controlled slow rate to the area surrounding the electrode ensuring continued stability and longer effective life for the electrode. The one or more diffusion ports also provide a low resistance current path to or from the lead within to the canister and the surrounding electrolyte.

Abstract: The invention relates to a cathodic protection system for above-ground storage tanks having metal bottoms, either new or retrofitted bottoms. A leak containing dielectric safety membrane is spaced a short distance below and extends beneath the tank bottom generally parallel thereto forming a narrow envelope. Compacted electrolytic conductor material is positioned between the membrane and the tank bottom supporting the tank bottom embedding a horizontally disposed cathodic protection anode, the anode being in the form of a matrix, maze or grid of interconnected titanium wires, or wires and ribbons or bars. A reticulate or open dielectric insulator may be embedded in the electrolytic conductor and positioned directly above the anode and such insulator is operable to keep any portion of the anode from contacting the tank bottom and to maintain a generally uniform spacing between the anode and tank bottom.

Abstract: A cathodic protection monitoring system which provides IR drop free cathodic protection potential measurements which are indicative of the effectiveness of the cathodic protection system. The system measures the polarized potential between a reference electrode and a coupon subsequent to decoupling the coupon from the protected structure. The present invention controls the time or times at which the potential is measured in order to ensure that the potential is measured only after the polarized potential has achieved a relatively steady state value. More particularly, the cathodic protection monitoring system controllably measures the polarized potential after the potential has stabilized to the extent that there are no inductive or capacitive voltage spikes present, and before the coupon potential decays significantly due to depolarization.

Abstract: A method and apparatus for the removal of chlorides from steel reinforced concrete utilizes an electrode with a rectifier impressing a voltage between the steel of the concrete and the electrode. The electrode and the surrounding concrete are saturated continuously with a controlled flow of an aqueous electrolyte. The aqueous electrolyte which may be water or salt water increases chloride movement within the concrete away from the steel reinforcing and improves the efficiency of the process by maintaining a saturated pore structure within the concrete. To facilitate such saturation of the concrete and electrode, the electrode may be immersed in a matrix of a porous water absorbing medium contained within a non-metallic membrane or jacket cover. In some forms, a collecting bin or reservoir is provided at the bottom to collect the aqueous solution for recirculation. For offshore or other installations, no collecting reservoir may be required.

Abstract: The invention relates to a cathodic protection system for an above-ground storage tank having a metal bottom, both new and retrofitted bottoms. A leak containing dielectric safety membrane is spaced a short distance below and extends beneath the tank bottom generally parallel thereto forming a narrow envelope. Compacted electrolytic conductor is positioned between the membrane and the tank bottom supporting the tank bottom embedding a horizontally disposed cathodic protection anode, the anode being in the form of a matrix or grid of interconnected titanium bars and ribbons. A reticulate dielectric insulator may be embedded in the electrolytic conductor and positioned directly above the anode and such insulator is operable to keep any portion of the anode from contacting the tank bottom and to maintain a generally uniform spacing between the anode and tank bottom. The ribbons extend transversely of the bars and are spot welded on uniform centers to bars on diameters or major chords of a circular tank bottom.

Abstract: A protective apparatus adapted for limiting corrosive effects of a liquid stored in a metallic storage tank. The apparatus includes anode means for carrying an impressed current to produce an electrolytic effect and inhibit corrosive interaction between the liquid and tank. Means for supplying electrical power is provided to the anode means and the anode means is supported from a side wall of the associated tank. Elastic members extend between the side wall and the anode means to maintain them in a submerged condition. Level compensator means includes a member having approximately neutral buoyancy so that it adds further weight to the apparatus as the liquid level decreases. Additionally, quick connect/disconnect means is provided to facilitate assembly and maintenance in existing and new storage tanks.

Abstract: A wire entrance fitting for eliminating leakage through a side wall of a tank has a tubular member which is externally threaded at opposed ends. Plural, threaded members are received in the tubular member and extend through an encapsulating, generally inert material. A first end of the threaded members receives an exposed wire from a cathodic protection system positioned in the tank for inhibiting corrosion, is crimped thereto, and sealingly encapsulated by a resinous material. A second end of the threaded members extends outwardly from the tank for connection to an external power supply. A flange is disposed along the tubular member and extends outwardly therefrom. The flange facilitates receipt of a junction box in one arrangement and positions an elastomeric seal member along an inner face of the tank side wall in a second arrangement.

Abstract: A replaceable deep anode system for the cathodic protection of underground metallic structures is disclosed. The system includes an anode casing received in a drilled hole. The casing has an electrically non-conductive upper portion and a substantially incorrodible electrically conductive lower portion preferably comprising a steel piping having a coating of a conductive polymer. A selectively insertable anode is received in the casing contiguous to the lower portion to define an active anode area. Electrically conductive material received in the casing adjacent the anode and about the casing lower portion provides a primarily electronic current path from the anode to the drilled hole wall. The casing provides an integral anode housing for selective removal and resupply of anodes as may be needed over a period of time. The conductive polymer preferably comprises a polymer concrete including conductive carbon elements.