دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: 1. one of two electrodes in an electrolytic cell;represented as the negative terminal of the cell, it is the area from which electrons flow. In a primary cell, it is the electrode that is wasted or eaten away. 2. in cathodic protection systems, an electrode to which a positive potential of electricity is applied, or a sacrificial anode, which protects a structure by forming one electrode of an electric cell.

the positively charged site in a cell. Oxidation site. The site of metal loss in corrosion.

v: to overcome the positive electrical potentials of anodic areas in cathodic protection systems.

n: 1. one of two electrodes in an electrolytic cell, represented as the positive terminal of a cell. 2. in cathodic protection systems, the protected structure that is representative of the cathode and is protected by having a conventional current flow from an anode to the structure through the electrolyte.

the negative site of a corrosion cell. Reduction reactions are typical.

n: a means of preventing the destructive electrochemical process of corrosion of a metal object by using it as the cathode of a cell with a sacrificial anode. Current at least equal to that caused by the corrosive action is directed toward the object, offsetting its electrical potential.

impressed current that offsets the current produced in a corrosion cell and reduces corrosion.

n: crushed coke used for packing underground anodes in cathodic protection systems to obtain increased anode efficiency at a reduced cost See coke.

n: the measures used to prevent or reduce the effects of corrosion. These practices can range from simply painting metal, to isolating it from moisture and chemicals and insulating it from galvanic currents, to cathodic protection, in which a galvanic or impressed direct electric current renders a pipeline cathodic, thus causing it to be a negative element in the circuit. The use of chemical inhibitors and closed systems are other examples of corrosion control.

n: in cathodic protection, a sacrificial anode that produces current flow through galvanic action. See sacrificial anode.

sacrificial anode.

n: in cathodic protection, an interconnected group of impressed-current anodes that absorbs the damage caused by generated electric current.

anodes buried in the earth to supply cathodic protection to equipment.

n: (OSHA) the first business with employees within the customs territory of the United States that receives hazardous chemicals produced in other countries for the purpose of supplying them to distributors or employers within the United States. impressed-current anode n: anode to which an external source of IK>sitive electricity is applied (such as from a rectifier or DC generator). The negative electricity is applied to a pipeline. casing. or other structure to be protected by the impressedcurrent method of cathodic protection.

n: a flange equipped with plastic pieces to separate its metal parts, thus preventing the flow of electric current. Insulating flanges are often used in cathodic protection systems to prevent electrolytic corrosion and are sometimes installed when a flow line is being attached to a wellhead.