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.

Abstract: There is disclosed a subsurface tubing safety valve having a normally closed flapper which is adapted to be moved to open position by a flow tube reciprocable within the body of the valve. The flow tube is urged to flapper opening position by hydraulic fluid from a remote source and is urged to a position permitting the flapper to close by a curved beam type spring.

Abstract: A device for limiting the torque transmitted from a drive shaft to a driven shaft comprising a first body having a cylindrical portion and being adapted for rotation with one shaft and a second body having a cylindrical portion and being adapted for rotating the other shaft. The cylindrical portion of one body is mounted within the cylindrical portion of the other body for relative rotation with respect thereto about an axis which is eccentric to the axis of rotation of the one body. A pin carried by the cylindrical portion of the other body for radial movement with respect thereto has inner and outer ends, with the inner end held engaged with the cylindrical portion of the one body by a C-ring to allow the drive shaft to rotate the driven shaft until the torque transmitted between them overcomes the C-ring to allow the cylindrical portions of the bodies to rotate relatively to one another.

Abstract: There is disclosed a subsurface tubing safety valve of the type having a flapper swingable between an open position to one side of its bore and a closed position over a seat about its bore. A seal ring retained in a groove about the seat has a protruding lip which is initially engaged by the flapper as it is swung toward the seating surface of the seat.

Abstract: A surface controlled, subsurface safety valve in which a force due to control pressure fluid from a first source at the surface for opening the valve is opposed in part by a force due to reference pressure fluid from a second source at the surface, whereby the valve closes in response to a fail condition.

Abstract: A fail safe valve actuator is disclosed that is powered by an electric motor. A valve stem with a helical groove is moved in one direction by a ball nut rotated by the electric motor to move a valve member to its operating position. The valve member is held in operating position by a solenoid. When power fails, a spring moves the valve stem in the other direction to move the valve member to its fail safe position. A torque limiting device protects the electric motor from the high torque created when the valve stem abruptly stops moving when the valve member reaches its operating position. A centrifugal brake absorbs a portion of the energy released when the power fails and the valve stem is moved rapidly to its fail safe position by the spring.

Abstract: There is disclosed apparatus for use in controlling flow through a tubing string suspended and packed off within a well bore and within the annulus between the string and well bore above and below the packer by tools adapted to be lowered into and raised from landed positions within a pocket to one side of a bore through a mandrel connected as part of the tubing string for releasing the packer to be set and opening a bypass therein and for opening and closing a flapper in the bore, as well as the bypass responsive to the supply of control fluid from a remote source to the pocket.

Abstract: There is disclosed a subsurface tubing safety valve of the type having a flapper pivotally mounted in the bore of a tubular body disposable in a tubing string, and a flow tube vertically reciprocable within the bore of the body between an upper position permitting the flapper to close the bore and a lower position engaging and moving the flapper into a recess in the side of the bore to open the bore. The flow tube is yieldably urged to its upper position and moved to its lower position in response to the supply of hydraulic fluid from a remote source to a piston engageable with the flow tube, and the flapper is yieldably urged to its closed position by means of an arm pivotally mounted on the body for extension over the lower surface of the flapper and a spring providing a vertically extending force acting between an end of the arm to one side of its pivotal axis and the body to urge the arm to a position to close the flapper.

Abstract: There is disclosed a well installation having an electrically responsive device a substantial distance beneath the wellhead and apparatus for supplying electrical current to the device from a source of alternating or time varying current outside the wellhead, which apparatus includes an electrical connector comprising a first coil on the outer side and a second coil on the inner side of a non-magnetic portion of a pressure containing wall of the well, whereby the supply of varying current from the source to the first coil forms an inductive coupling between it and the second coil of the connector.

Abstract: There is disclosed apparatus for use in completing oil or gas wells having two or more perforated production zones which includes packers and assemblies for closing off the annular space between the tubing string and the well bore intermediate adjacent zones to isolate one from the other in order to produce from each individually.

Abstract: There is disclosed a pneumatic gate valve actuator adapted to move the gate of the valve between opened and closed position by the introduction of air pressure into or the exhaustion of air pressure from an expandable and contractible pressure chamber formed within a tire casing and between upper and lower plates having their peripheries connected to inner edges of a tire casing. The lower plate is connected to the stem for the gate, the upper plate is connected to the bonnet of the actuator, and a coil spring is compressed between the lower plate and the bonnet, so that the gate may be moved to open position upon the supply of air pressure to the chamber, and moved to closed position upon the exhaust of air pressure from the pressure chamber.

Abstract: There is disclosed a tool which is adapted to be lowered and raised through a well conduit into and out of a centered position within a well bore beneath the lower end of the conduit. The tool has arms which are spring pressed toward outer positions for engaging the well bore, but held in inner positions in which they may move vertically through the well conduit until the tool has been lowered into a bore near the lower end of the well conduit, and then returned to and reheld in such position upon raising of the tool above the bore during retrieval of the tool.

Abstract: There are disclosed two embodiments of a valve for closing a well conduit within a wall bore to flow therethrough automatically in response to the loss of a controlled condition. Each embodiment of the valve has means in which energy may be generated, in response to bleeding off of pressure above the closed valve. So long as the controlled condition is maintained, the return of a pressure balance across the closed valve will permit the release of generated energy to open the valve. The loss of the controlled condition releases further generated energy to close the valve.

Abstract: A multiple well string packer of the type wherein the packer is lowered into a well bore on one of the well strings, and the one string hung off from the wellhead so that the packer may be set at a desired level therein, and wherein the packer, when unset, is retrieved from the well bore on the same string, the other string or strings being lowered into and raised from connection with the packer, when disposed at such level, separately of the one string.

Abstract: There is disclosed a device for latching a well tool within the seal bore of a pocket to one side of a bore through a mandrel connectable in the well string. The mandrel has a recess above the seal bore to receive latching dogs on the lower end of collet fingers carried by the device and an upwardly facing shoulder above the recess which engages the latching dogs to cause them to be flexed inwardly as they are lowered into positions opposite the recess.

Abstract: There are disclosed several embodiments of a fail safe gate valve and actuator having means for yieldably urging the gate from one position to which it is moved under one or more controlled conditions to its other position upon failure of one such condition, means including a handwheel mounted on the actuator for moving the gate to its one position, and means automatically responsive to a control signal for rendering the handwheel inoperative to move the gate to its one position upon reestablishment of said one controlled condition. In certain embodiments, the control signal is automatically responsive to the reestablishment of said one controlled condition; and, in another embodiment, it is automatically responsive to the failure of said one controlled condition. The controlled conditions are disclosed as being one or both of a predetermined fluid pressure condition, and or a predetermined environmental temperature condition.

Abstract: Well apparatus is disclosed in which the bore through a lower tubular body adapted to be packed off and anchored within a well bore is opened and closed by a flapper pivotally mounted on the lower body and spring pressed toward closed position, and a flow tube mounted for reciprocation within the bore of an upper tubular body releasably connected to the lower body extends downwardly through the bore of the upper and lower bodies to a position for engaging and moving the flapper to open position, as the flow tube is lowered by means of control fluid supplied to a pressure responsive operator connected to the flow tube, and permitting the flapper to close as the control fluid is exhausted from the operator.

Abstract: There is disclosed a kickover tool for use in running or pulling well tools respectively into or from a side pocket to one side of a bore through a mandrel connected as part of a well string.

Abstract: There are disclosed two embodiments of a packer for closing off the annular space between a pipe string and a well bore in which the pipe string is disposed, each of which includes an annular packing element adapted to be expanded into sealing engagement with the well bore in response to relative axial movement between inner and outer tubular members, and releasably latched in expanded position by means which includes a circumferentially expandible and retractable body lock ring. In each case, the body lock ring has cam teeth about its outer side which are engaged with cam teeth on the inner circumference of the outer tubular member for circumferential expansion and contraction with respect thereto, and a relatively long length of ratchet teeth on its inner side for ratcheting with respect to a relatively short length of ratchet teeth on the outer circumference of a latching member carried by the inner tubular member in response to movement of the tubular members to retracted positions.