Protective Anode – A metallic object designed to corrode in place of the object it is designed to protect.
Cathodic ProtectionNote 30 – A technique to prevent the corrosion of a metal surface by making that surface the cathode of an electrochemical cell.
Cement, Portland Cement – A cement that contains oxides of calcium, aluminum, iron, and silicon made by heating a mixture of limestone and clay in a kiln and pulverizing the resultant clinker, as defined in ASTM C150. Portland cement is also considered a hydraulic cement, because it must be mixed with water to form a cement-water paste with the ability to develop strength and harden, even under water.
Centralizer – A device that assists in centering tubular materials in a borehole.
Conductance, Specific – A measure of the ability of water to conduct electric current at 77 degrees Fahrenheit. It is related to the total concentration of irons in the water.
CorrosionNote 30 – The deterioration of a material, usually a metal, because of a reaction with its environment.
Drilling Fluid – A fluid (liquid or gas) used in drilling operations to remove cuttings from a borehole, to clean and cool the drilling bit, to reduce friction between the drill stem and the borehole wall, and, in some cases, to prevent caving or sloughing of the borehole.
ElectrolyteNote 30 – A chemical substance or mixture, usually liquid, containing ions that migrate in an electric field. The term electrolyte refers to the soil or liquid adjacent to, and in contact with a buried or submerged metallic structure including the moisture and other chemicals contained therein.
InterferenceNote 30 – The situation that arises when a foreign substructure is affected in any way by a direct current source.
RectifierNote 30 – An electronic device that changes alternating current to direct current.
|Table of Contents     Appendix B|