دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: A large BOP (q.v.) valve that forms a seal in the annular space between the wellbore and the drill pipe. It is usually installed above the ram type preventers in the BOP stack.

a elastomer bag or donut type seal, pushed into contact with the pipe or tools in the blow out preventer (BOP). It is designed to seal around pipe or any other irregular surface tool (packers, guns, pumps, etc.) that may be in the BOP. May also be called

v: to close a ram blowout preventer around the drill pipe when the annular preventer has previously been closed to offset the effect of heave on floating offshore rigs during well-control procedures.