Locking assembly for mechanically set packer

摘要

A lock assembly for a mechanically set packer for deep deployments is described. The lock housing wall has at least one bore for a rod piston that is selectively actuated when wellbore hydrostatic is allowed to reach on side of the piston. Movement of the piston, after breaking a shear pin, allows a c-ring to spring outwardly and out of a locking groove in the mandrel so that the mandrel can be string manipulated with respect to the housing to set the packer. Once unlocked the lock assembly remains defeated. The piston can be optionally exposed to hydrostatic and will unlock at a given depth without manipulation of the wellbore annulus pressure. Other mechanisms to admit wellbore hydrostatic to move the piston or to move the piston in general by other techniques are described.

主权项

1. A lock assembly for a subterranean tool that sets with mandrel movement relative to a body of the tool, comprising:
a housing supported by the tool body and having a mandrel extending into a passage in said housing; a locking member retained in a profile on an exterior mandrel surface by a selectively movable retainer, said retainer movable to release said locking member in response to at least one pressure actuated rod mounted in at least one hydraulically pressurized bore in a wall of said housing that moves said retainer with respect to said locking member: and said rod abutting said retainer in said bore when said locking member is retained to said mandrel.