Dissolvable subterranean tool locking mechanism

摘要

A hydrostatically set packer is held against setting by a locking member that is made of controlled electrolytic material (CEM). After introduction into a wellbore and exposure to thermal or well fluid inputs the lock made of CEM dissolves or is otherwise weakened to the point where relative movement can occur for the setting of the packer with available hydrostatic pressure. The locking member can also be a shape memory alloy at least in part whose shape change allows the tool to set.

主权项

1. An automatically operating lock for a subterranean tool, comprising:
a mandrel an actuated member on said mandrel selectively movable by an actuating member on said mandrel to define a set position for the tool; a lock further comprising at least one dog or ring extending through at least one opening in said actuating member to selectively retain said actuating member to a groove in said mandrel by virtue of a covering sleeve supported by said mandrel to define a run in position for the tool, said at least one dog or ring in direct mechanical contact with said actuating member and exposed to subterranean conditions during delivery to a desired subterranean location, said at least one dog or ring automatically releasing said actuating member to move relative to said mandrel in response to adjacent subterranean conditions.