Patent ID: 9719326
Date: 2017-08-01
CPC Classifications: E21B

Claim:
1. A valve for engaging a backup hydraulic system to operate a subterranean tool from a primary hydraulic system, comprising: a subterranean tool having a movable member actuated by a primary piston or a secondary piston; a valve having two inlets to respectively connect a primary control line and a secondary control line that each extend to the tool from a remote location; said valve comprising a valve member axially slidable from a first position where said primary control line is in flow communication with said primary piston to a second position where said secondary control line, as a direct result of said valve member moving to said second position, is in communication with said secondary piston by application of pressure in one of said control lines, said application of pressure directly axially sliding said valve member between said positions such that said sliding of said valve member alone puts said primary piston in pressure balance from said primary control line and opens a hydraulic circuit between said secondary control line and said secondary piston for backup operation of the subterranean tool.