Hydraulic release oil tool

摘要

A hydraulic setting and release tool has a shear out setting assembly attached to a string coupling member. Upon reaching a predetermined hydraulic pressure, a piston of the tool shears restraining shear pins and moves in a body of the tool to release dogs that engage the coupling member. When used in running in a liner, the coupling member is a running head that rotates the liner during running in and cementing. When used as a drill string release tool, the coupling member is a release sub, the tool being placed serially with other string components. If the drill string gets stuck, it is separated by merely increasing the hydraulic pressure sufficiently to shear the pins and allow the piston to move and the dogs to retract to separate the release sub from the shear out assembly.