Abstract: A sliding sleeve is provided to control the flow of fluids through a tubular conduit. The sliding sleeve may include a housing having a longitudinal bore, at least one annulus pressure port, and at least one fluid flow port. An inner sleeve is disposed for axial movement within the longitudinal bore of the housing, and includes at least one fluid flow port for sealably cooperating with the fluid flow port in the housing to control the flow of fluids through the tubing string. A piston is associated with the inner sleeve and the housing. The piston is initially releasably secured to the housing. The sliding sleeve is initially provided with the fluid flow ports in a closed position, and is actuated by applying annulus pressure to the piston through the at least one annulus pressure port in the housing. The annulus pressure releases the piston from the housing and forces the piston and inner sleeve upwardly to establish fluid communication through the fluid flow ports.

Abstract: A subsurface safety valve of minimized length comprises a tubular valve housing with a valve closure member therein movable between an open and a closed position, an axially shiftable flow tube for opening the valve closure member, a plurality of longitudinally disposed springs radially spaced about the housing for biasing the flow tube to a closed position, and a piston and cylinder assembly to move the flow tube to an open position, with a portion of the assembly longitudinally overlapping at least one of the springs. The safety valve includes simple mechanisms to lock out the safety valve, and to establish secondary hydraulic communication with a wireline set secondary valve set within the locked out safety valve.

Abstract: There are disclosed methods and apparatus for perforating and treating zones of a well, as by hydraulic fracturing, stimulating and acidizing, and otherwise performing related activities within a well, wherein a plurality of perforating assemblies containing shaped charges are connected as part of a casing liner which is lowered into a well bore and then anchored therein by a column of cement in the annulus between the liner and bore to locate the assemblies opposite zones in a horizontal section of the well. Work strings are lowered into selected assemblies to cause tools carried thereby to sequentially detonate the shaped charges to perforate the zone opposite thereto and to selectively open or close the perforated zones by shifting a sleeve within a housing of the assembly as well as treating the perforated zones.

Abstract: Well apparatus is disclosed in which a tool is lowered on a pipe string into a well conduit for shifting a sleeve slidably mounted within a tubular housing connected as part of the well conduit. The sleeve has vertically spaced grooves about its inner diameter, and the tool has latches which are selectively moved into and out of engagement with a selected groove in the sleeve in response to the control of the pressure of fluid within the tool. When engaged in a groove, the tool may be raised or lowered with the pipe string to raise or lower the sleeve.