دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: 1. a hook-shaped wrench that fits the square shoulder of a sucker rod and is used when rods are pulled or run into a pumping oilwell. Usually used in pairs;one key backs up and the other breaks out or makes up the rod. Also called a rod wrench. 2. a slender strip of metal that is used to fasten a wheel or a gear onto a shaft. The key fits into slots in the shaft and in the wheel or gear. v: to use a cotter key to prevent a nut from coming loose from a bolt or a stud.