Abstract: A well safety valve for use in a fluid well conduit through which fluid is produced by pumping. A body is adapted to be inserted into the conduit and includes a passageway for well fluid. A valve in the passageway opens and closes in response to the fluid level or hydrostatic pressure in the conduit. When pumping is discontinued, the fluid level in the conduit increases to a predetermined high level to close the valve. When pumping begins, the fluid level falls and when it reaches a predetermined low level the valve is opened. The valve includes an equalizing device.

Abstract: An annulus subsurface safety valve for installation between inner and outer concentric members and controlling a fluid passageway therein in which the safety valve is locked to the outer member when the fluid passageway is closed. The outer member is provided with a threaded section and the safety valve housing includes a plurality of segments carried for inward and outward movement in which the segments include threads on the outside for coacting with the threaded section. A lock is provided upon the valve closure of the safety valve and positioned to be out of engagement with the segments when the valve is in the open position but is in engagement with and locks the segments outwardly in engagement with the threaded section when the valve is in the closed position. Springs urge the segments outwardly whereby the valve may be ratcheted downwardly into the threaded section and can be released from the threaded section by opening the passageway or can be released by rotation.

Abstract: A tubular housing having an inner tubular member forms an inner passageway inside of the inner member and an outer passageway between the inner member and the housing. The housing has valve openings leading from the outer passageway to the exterior of the housing and a tubular valve closure member telescopically moves on the interior of the housing. First means move the valve closure member in an upper direction for closing the openings and at least one actuating piston is telescopically movable within and has its longitudinal axis in the wall of the housing and engages the valve closure member. The piston is in communication with a hydraulic passageway adapted to extend to the well surface for actuating the closure member in a direction to open the valve openings. The closure member is positioned whereby upward flow through the outer passageway acts on the closure member to close the valve opening.