IMPROVED FULL BORE NIPPLE AND ASSOCIATED LOCK MANDREL THEREFOR

摘要

An improved full bore nipple and associated lock mandrel provides enhanced sealing capability in tubing strings positioned in subterranean wells. In a described embodiment of the full bore nipple, a nipple body has a recessed seal surface and a latch profile formed on an internal bore of the body. In a described embodiment of the lock mandrel, an expander sleeve radially outwardly expands a circumferential seal to sealingly engage the recessed se al surface, locks a series of keys into the latch profile, and displaces anothe r seal to sealingly engage an outer housing, when the expander sleeve is displaced axially downward relative to an inner mandrel of the lock mandrel.