دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a kind of tools assembly in which a rolling cutter reamer

is joined among two or three drill collars and a stabilizer is joined on each end of the drill collar respectively

n: see keyseat wiper.

n: a device used to ream out a hole where keyseating has occurred. Usually a bumper sub is used first to loosen stuck pipe from a sharp bend, and then a keyseat wiper is used to enlarge the hole at the keyseat caused by the pipe. Also called

n: a tool made up in the drill string to ream out any keyseats that may have formed and thus prevent the pipe from becoming struck.