Abstract: A main anode and a pilot anode are mounted on a coating film of a metal structure, a cathode is mounted on a metal based material of the metal structure, a predetermined voltage is applied from the pilot anode to the metal structure, a magnitude of corrosion protection current of the metal structure is read from a current value of the pilot anode varying with variation of corrosion environment of the metal structure, the application voltage of the main anode is increased or decreased in accordance with the current value, whereby providing a cathodic protection method and apparatus for a metal structure capable of expanding protectable area by a single anode to a maximum without causing over-corrosion protection.

Abstract: A semiconductor system is provided that uses semiconductive organic polymers, electronics and semiconductor technology to provide a wide array of semiconductor components and a system of preventing corrosion of a surface of a metal structure in contact with a corrosive environment involving:

Abstract: A method for monitoring and reducing corrosion in furnace boiler tubes measures electrochemical noise associated with corrosion mechanisms while corrosion is occurring at the surface of the tubes as they are exposed to combustion products. This noise is detected using a probe at the boiler waterwall surface that is connected to a corrosion monitor. The monitor contains a computer and software which determines a corrosion rate from the measured electrochemical noise. That rate is compared to a standard to determine if the rate is within acceptable limits. If not, the operator of the furnace or an Adaptive Process Controller (APC) is notified and adjusts one or more burners to change the combustion products that are responsible for the corrosion. Such an adjustment could be made by changing the amount of air or fuel being provided to the burner or other air slots or air ports.

Abstract: A concrete structure is reinforced with steel rebars coated with essentially pure aluminum in the range from about 0.25 mm to 2 mm thick upon which aluminum coating is an aluminum oxide layer in the range from 0.1 &mgr;m to 100 &mgr;m thick. This layer of aluminum oxide and/or hydrated aluminum oxide is referred to as a combined aluminum oxide layer, and it is in direct contact with the concrete.

Abstract: Combining an electroosmosis direct current (EP) applied at less than 1 mA/Mcm3 (milliamp per 1000 cm3 of concrete) with an anode placed adjacent an outer surface of reinforced concrete soaked with a substantially neutral saline solution, effectively depletes corrosive anions in the concrete even when the direct current is in the range from 0.01 mA to less than 1 mA and at a voltage less than 100 V. Further, using such electroosmotic treatment as a first treatment, and promptly following it with cathodic protection, preferably by an impressed cathodic current (CP) at a comparably low voltage, the current density of CP required for cathodic protection is unexpectedly reduced. This decrease in the required current density of impressed current CP, coupled with low installation and operational costs of the novel system, improves the efficiency of a conventional cathodic protection system, whether by impressed current or with sacrificial anodes, several fold, as high as by a factor of 3 to 30 times.

Abstract: An apparatus for prevention of corrosion in metal objects uses a capacitively coupled fastener or pad attached to a metal body being protected from corrosion. The metal body and the negative terminal of a source of DC voltage (battery) are grounded. The positive terminal of the source of DC voltage is connected to electronic circuitry that imparts pulses of low voltage DC through the capacitor to the fastener. These pulses of electrical current inhibit the oxidation of the metal object by providing a source of electrons to the oxidizing chemicals in contact with the metal. The electronic circuitry includes a reverse voltage protector to prevent the application of reverse source voltage. The circuitry also includes a power conditioner to supply a constant DC voltage to a microprocessor. The microprocessor generates pulses of DC signals that are amplified by a pulse amplifier and imparted to the conductive facing of the pad. For larger objects, a first and second cable are attached to a metal object.

Abstract: A concrete structure is reinforced with steel rebars coated with essentially pure aluminum in the range from about 0.25 mm to 2 mm thick upon which aluminum coating is an aluminum oxide layer in the range from 0.1 &mgr;m to 100 &mgr;m thick. This layer of aluminum oxide and/or hydrated aluminum oxide is referred to as a combined aluminum oxide layer, and it is in direct contact with the concrete.

Abstract: An apparatus for prevention of corrosion in metal objects uses a capacitively coupled fastener or pad attached to a metal body being protected from corrosion. The metal body and the negative terminal of a source of DC voltage (battery) are grounded. The positive terminal of the source of DC voltage is connected to electronic circuitry that imparts pulses of low voltage DC through the capacitor to the fastener. These pulses of electrical current inhibit the oxidation of the metal object by providing a source of electrons to the oxidizing chemicals in contact with the metal. The electronic circuitry includes a reverse voltage protector to prevent the application of reverse source voltage. The circuitry also includes a power conditioner to supply a constant DC voltage to a microprocessor. The microprocessor generates pulses of DC signals that are amplified by a pulse amplifier and imparted to the conductive facing of the pad. The invention also includes a battery voltage monitor and a power indicator.

Abstract: An electro-chemical process for rehabilitating steel reinforced concrete, wherein a distributed flow of electrical current is established between internally embedded reinforcing steel, connected as a cathode, and an external, distributed electrode, connected as an anode. Current flow at a rate of at least 0.1 ampere per square meter of surface area of the embedded reinforcement is continued for a time sufficient to provide a total charge of at least about 100, but not substantially more than 2000, ampere-hours per square meter of surface area of the embedded reinforcement. This results in steel with a clean surface, surrounded by concrete which is chloride free and highly alkaline. After discontinuance of the electrochemical treatment, the embedded steel slowly passivates by forming a protective surface oxide. The process is significantly more economical than known procedures, yet is reliably effective.

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: A cathodic protection system utilizes dynamic control of an output from a power supply to vary an impressed current applied to a structure to be protected proportional to a measurement of stray electrical current. The current is also supplied to an anode bed in an amount sufficient to maintain the structure more negatively charged than the anode bed such that the stray electrical currents are directed away from the structure, thus avoiding electrolytic attack.

Abstract: Several embodiments of reference electrode constructions for use in electrically anti-corrosion protection systems for marine outboard drives. In each embodiment the reference electrode is contained within a protective covering with a restricted small volume area surrounding the reference electrode. As a result, when the reference electrode dissolves in the body of water in which it is operating it will form a saturated solution in this small volume area to preclude further dissolution.

Abstract: An electrochemical stain prevention apparatus of a submerged structure comprising a submerged structure of which at least the stain prevention surface is formed of a conductive film that does not generate chlorine even by applying a potential of 5 V vs. SCE or less, a counter electrode located so as not to contact with the submerged structure, and a power supply unit for passing a direct current through the submerged structure having the conductive film formed thereon and the counter electrode. Aquatic organisms adhered to the surface of the conductive film can effectively be controlled by applying a potential of from 0.1 to 5 V vs. SCE to the submerged structure of such a stain prevention apparatus without generating chlorine. A potential applied to the conductive film of the submerged structure can be controlled with good accuracy by disposing a reference electrode between the submerged structure and the counter electrode.

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: A galvanic monitor system uses two annunciators, such like light emitting diodes, to alert a boat operator of the current status of the boat's galvanic protection system. A reference electrode is used to monitor the voltage potential at a location in the water and near the component to be protected. The voltage potential of the electrode is compared to upper and lower limits to determine if the actual sensed voltage potential is above the lower limit and below the upper limit. The two annunciators lights are used to inform the operator if the protection is proper or if the component to be protected is either being over protected or under protected.

Abstract: A marine fouling prevention system comprises two conductive surfaces and a device that alternates the direction of electric current between the two surfaces. The current is caused to flow through sea water in which the two surfaces are submerged or partially submerged. A monitor measures the current flowing from one of the two conduction surfaces and compares it to the current flowing into the other conduction surface to assure that no leakage of current of substantial quantity exists. The system applies a low magnitude current density, of approximately 0.10 to 0.50 milliamperes per square foot, for an extended duration of time of approximately 10 to 20 minutes. By alternating current direction between the two surfaces, both surfaces can be provided with sufficient chlorine gas bubbles to prevent marine growth from attaching to the surfaces.