Abstract: A pulling tool for retrieving well tools from a well bore. The present invention allows the reach of the pulling tool to be easily varied. The pulling tool can also be assembled for emergency release by either upward or downward shearing forces. The weight of a well tool engaged by the pulling tool is fully supported by the housing of the pulling tool. A manual release feature is provided to release well tools from the pulling tool at the well surface without having to disassemble the pulling tool or shear any pins.

Abstract: A system for releasably anchoring well tools within a tubing string at a preselected downhole location. The system includes a running tool, locking mandrel, and landing nipple. Control fluid pressure is used to ensure positive engagement of the locking mandrel within the landing nipple prior to releasing the running tool from the locking mandrel. The locking mandrel and running tool are particularly useful for installation of surface controlled subsurface safety valves. However, the system can be used to install a wide variety of flow control devices and/or well tools.

Abstract: A safety valve which prevents undesired fluid flow while conducting hydraulic workover or snubbing operations on a well. The safety valve includes three separate valve portions for blocking fluid flow. A poppet valve can be opened and closed from the well surface. Elastomeric sealing elements form a fluid barrier with the exterior of the work string. The work string itself opens and closes a flapper valve. The poppet valve allows fluid flow to bypass the elastomeric sealing elements.

Abstract: In a locking mandrel for releasably locking a well tool in a well flow conductor of the type disclosed in U.S. Pat. No. 3,208,531 which includes a tubular body mandrel adapted for securing with a running tool and with a well tool, a locking dog retainer sleeve on the body mandrel, expandible and contractible locking dogs carried by the retainer sleeve, and a locking sleeve movable on the body mandrel within the retainer sleeve between a first position at which the locking dogs are expanded and release positions at which the locking dogs are movable inwardly to release positions, the improvement for releasably latching the locking sleeve at the first locking position on the body mandrel which includes an annular latching boss on the body mandrel and an annular latching flange and recess within the locking sleeve.