PLUG INSTALLATION AND RETRIEVAL TOOL FOR SUBSEA WELLS

摘要

A plug retrieval and installation tool comprises a housing (50) that is lowered on a lift line or riser and connected to subsea production equipment such as a tree (30) and wellhead housing (16) in use. A plug manipulator (70) which can be extended to install, or retracted to retrieve, a plug-type barrier (22), is detachably mounted to the housing so that it can be retrieved independently of the housing. In the event that the plug manipulator fails, it may therefore nevertheless still be detached from the housing and retrieved, for example by wireline, through a riser and suitable pressure control equipment. The plug (22) is retrieved from/installed in a tubing hanger profile (23) through the tree (30). The housing (50) may comprise an LRP (50), having selectively openable pressure containment facilities, through which the plug manipulator (70) may be removed. The installation tool eliminates the need for full-size intervention vessels or drilling rigs for plug retrieval/installation.