FAILSAFE LINER INSTALLATION ASSEMBLY AND METHOD

摘要

An apparatus and method for installation of oil field tubulars, such as liners, is disclosed. The invention allows positioning of a liner with assurances that rotational forces or pressure applied within or outside the work string will not actuate the packer (14) or the release assembly (202) above the packer. Specific deliberate steps must be taken in order that rotational forces or applied pressure actuate the packer setting assembly (14) and the disconnect assembly. The preliminary deliberate steps which must be taken also incorporate a feature of converting a gravel pack crossover assembly (16) from the flow through mode to the crossover mode to facilitate the gravel placement. Circulation or reverse circulation to promote removal of debris upon insertion of the assembly without fear of actuation of the packer (14) and disconnect assembly (202) are also provided. A retention system to ensure the continuing functioning of the crossover assembly (16) in the crossover mode is provided such that if differential forces on the sealing member (50 and 52) are reduced to a very low value, the retaining mechanism acts to keep the sealing member (50 and 52) against the seat (82) to ensure continuing viability of operation of the crossover assembly during the placement of the gravel. The unlocking is accomplished with a series of steps which involve reuse of an auxiliary sealing member in at least two positions in the wellbore.