دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: see electromotive series.

n: a list of elements arranged in order of activity (tendency to lose electrons). The following metals are so arranged: magnesium, beryllium, aluminum. zinc, chromium, iron, cadmium, nickel, tin. copper, silver, and gold. If two metals widely separated in the list (e.g., magnesium and iron) are placed in an electrolyte and connected by a metallic conductor, an electromotive force is produced. See corrosion.

n: in cathodic protection. anodes made from metals whose galvanic potentials render them anodic to steel in an electrolyte. They are used up. or sacrificed.

a metal slug, lower in the electromotive series than steel that is hard wired to the casing and buried in a bed of wet soil or below the surface of the water. The corrosion cell in the well then transfers the current to the new anode and the steel in the