Abstract: A new method for introducing wellbore cement into a wellbore shoe joint has been invented, the shoe joint having a hollow tubular body, the shoe joint containing an amount of wellbore fluid, the shoe joint disposed in a wellbore cementing system between a float shoe, guide shoe, or other flow apparatus beneath the shoe joint, and a hollow tubular member above the shoe joint, the hollow tubular member being a lower part of a wellbore tubular string of a plurality of tubular members (e.g., casing) extending from an earth surface down into a wellbore, the method including moving a wellbore wiper plug into the hollow tubular body of the shoe joint, moving the plug within the shoe joint to push wellbore fluid from the shoe joint and, in one aspect, debris in the fluid, the fluid flowing to the float shoe, guide shoe or other flow apparatus, flowing wellbore cement into the hollow tubular body of the shoe joint.

Abstract: A new wellbore cementing system has been developed which includes, in certain embodiments, a plug container with a flow diverter for diverting a portion of flowing fluid away from plugs in the plug container; a plug set system with internal sleeves or dart receivers with shearable parts for shearing to selectively release plugs--all in certain embodiments made of non-metal material and/or plastic; a swivel equalizer with internal valving to isolate a plug set (or any other item) from torque and to relieve pressure below the swivel equalizer; and unique burst tube systems for selectively controlling fluid flow and plug system operation. In one aspect a plug nose is tapered to correspond to a taper of a landing ring so that wedge-locking of the nose and ring effects desired non-rotation of the plug during drilling. In one aspect plug fin bending is facilitated by reducing plug body thickness so that an alternate fluid flow path is provided for cementing.

Abstract: A new fill valve for use in cementing operations in a wellbore extending down into the earth has been invented, the fill valve having a tubular housing having a valve seat, a valve member slidably mounted in said tubular housing, a spring for biasing said valve member towards a closed position, the valve member having a head engageable with the valve seat of the tubular housing to close the valve, selectively releasable apparatus for releasably maintaining the fill valve in an open position, the selectively releasable apparatus including a shear ring breakable in response to pressure thereon, a slider movably disposed in a slider housing mounted in the tubular housing, a lower end of the slider initially projecting down and out from the slider housing and abutting a top end of the valve member and preventing the valve member from moving, a top end of the slider abutting the shear ring, the slider prevented initially from moving by the shear ring, the slider movable in response to pressure of fluid in the well

Abstract: A new wellbore cementing system has been developed which includes, in certain embodiments, a plug container with a flow diverter for diverting a portion of flowing fluid away from plugs in the plug container; a plug set system with internal sleeves or dart receivers with shearable parts for shearing to selectively release plugs--all in certain embodiments made of non-metal material and/or plastic; a swivel equalizer with internal valving to isolate a plug set (or any other item) from torque and to relieve pressure below the swivel equalizer; and unique burst tube systems for selectively controlling fluid flow and plug system operation.

Abstract: A new wellbore cementing system has been developed which includes, in certain embodiments, a plug container with a flow diverter for diverting a portion of flowing fluid away from plugs in the plug container; a plug set system with internal sleeves or dart receivers with shearable parts for shearing to selectively release plugs--all in certain embodiments made of non-metal material and/or plastic; a swivel equalizer with internal valving to isolate a plug set (or any other item) from torque and to relieve pressure below the swivel equalizer; and unique burst tube systems for selectively controlling fluid flow and plug system operation.

Abstract: A fill valve includes a tubular housing which accommodates a valve member which is biased toward a closed position by a light spring. The valve member includes a head and a tubular portion which is provided with two large windows. When the fill valve is open fluid flows freely through the tubular portion of the fill valve and out of the windows.

Abstract: A new cementing system has been developed which includes, in certain embodiments, a plug container with a flow diverter for diverting a portion of flowing fluid away from plugs in the plug container; a plug set system with internal sleeves or dart receivers with shearable parts for shearing to selectively release plugs--all in certain embodiments made of non-metal material and/or plastic; and a swivel equalizer with internal valving to isolate a plug set (or any other item) from torque and to relieve pressure below the swivel equalizer.

Abstract: A casing inflation packer for use in a casing string in a well bore. The apparatus includes a housing connected in the casing string. An inflatable packer portion on the housing sealingly engages the well bore when inflated. An inflation passageway is defined between a housing central opening and the packer. A rupture disc is initially disposed between the central opening and the inflation passageway for preventing communication therebetween. The rupture disc ruptures in response to a first predetermined pressure, thereby placing the central opening in communication with the packer through the inflation passageway. A slidable control valve is disposed in the inflation passageway and is initially shearably held in an open position. Upon application of a second predetermined pressure across the valve, the valve is moved to a closed position, thus preventing overinflation of the packer and also preventing deflation thereof.

Abstract: Expandable casing portions are provided, such as casing slip joints or expansion joints, on opposite sides of a fracture initiation location to accommodate casing and formation movement during fracturing of a well. The fracture initiation location may be provided by forming openings through the well casing and then forming fan-shaped slots in the formation surrounding the casing. These slots may be formed by a hydraulic jet which is directed through the opening and then pivoted generally about the point of the opening. These fan-shaped slots circumscribe an angle about the axis of the casing substantially greater than the angle circumscribed by the opening itself through which the slot was formed. These techniques are particularly applicable to fracturing of horizontal wells, but are also useful on vertical wells.

Abstract: A stage cementer and inflation packer apparatus. The apparatus comprises a mandrel with an external closing sleeve and an operating sleeve interlocked therewith. Below the operating sleeve is an opening sleeve. The opening sleeve is mechanically acutated by a pump-down plug in a plug-operated embodiment or by a differential pressure acting on the opening sleeve in a hydraulically operated embodiment, to actuate the opening sleeve to allow inflation of the packer element. A back check valve prevents the packer from deflating. After the packer is inflated, additional pressure is applied which ruptures a rupture disc to open a port to the well annulus above the set packer element. Cementing may be carried out through this port, and after the cementing operating, a plug engages the operating sleeve to move the operating sleeve in the external closure sleeve, thereby closing the cementing port.

Abstract: A casing packer apparatus includes a mandrel having a mandrel exterior, a longitudinal mandrel bore defined therethrough, and a power port defined in the mandrel communicating the mandrel bore with the mandrel exterior. A packer element is concentrically received about the mandrel. An annular piston is concentrically received about the mandrel and has an annular differential pressure area defined thereon and communicated with the mandrel bore through the power port. The annular piston and packer element are operably associated so that the packer element is set by sliding motion of the piston in response to increased fluid pressure in the mandrel bore. Either a compression set packer element or an inflatable packer element may be utilized.

Abstract: A wedge lock ring apparatus includes an outer housing having a housing bore with a housing groove defined therein. The housing groove has at least one and preferably has upper and lower housing groove tapered sides. An inner sleeve has a cylindrical outer surface with a sleeve groove defined therein, and the sleeve groove has at least one and preferably has upper and lower sleeve groove tapered sides. A wedge lock ring is received in the housing groove and the sleeve groove and has ring tapered edges complementary to the housing groove tapered sides and sleeve groove tapered sides, such that the sleeve and housing are locked against relative rotation by wedged engagement with the lock ring.

Abstract: A casing cementer with torque-limiting rotating positioning tool. The casing cementer comprises a housing with a rotating valve sleeve therein. A positioning tool is used to rotated the valve sleeve between open and closed positions thereof. No reciprication of the positioning tool is required. The valve sleeve has a sealing ring molded thereto for sealing between the housing and the valve sleeve. The valve sleeve preferably has an inside diameter at least as large as an inside diameter of the casing. A stop is provided to limit movement of the valve sleeve when it reaches either the open or closed position. A clutch in the positioning tool provides for torque-limitation and a ratcheting indication to the operator at the surface when the valve sleeve has been opened or closed.

Abstract: A multiple stage inflation packer with secondary opening rupture disc. The inflatable packer comprises a case with a closing sleeve, an opening sleeve and a releasing sleeve therein. An opening plug is dropped into the casing string and is allowed to free fall, or is pumped down, to actuate the opening sleeve to allow inflation of the packer element. A back check valve prevents the packer from deflating. After the packer is inflated, additional pressure is applied which ruptures a rupture disc to open a port to the well annulus above the set packer element. Cementing may be carried out through this port, and after the cementing operation, a closing plug is pumped down the well casing behind the cement to actuate the releasing sleeve and move the closing sleeve to seal off the ports. Another check valve insures that pressure is equalized on both sides of the rupture disc as the packer is run into the well bore.

Abstract: A cementing tool includes a tubular housing having an inner passage defined longitudinally therethrough and having a radially outer surface. The housing also has a cementing port and a longitudinal slot both disposed through a wall thereof. An outer closure sleeve is slidably received about the outer surface of the housing and is movable relative to the housing between an open position wherein the cementing port is uncovered by the closure sleeve and a closed position wherein the cementing port is closed by the closure sleeve. An inner operating sleeve is slidably received in the housing and slidable between first and second positions relative to the housing. A pin extends radially through the slot and fixedly connects the operating sleeve and the closure sleeve together for common longitudinal movement relative to the housing. When cementing is completed, a cementing plug engages the operating sleeve and causes it to move the external closure sleeve downward thus closing the cementing port.

Abstract: A sliding sleeve casing tool installed in a casing string comprising a housing, sliding sleeve, seal members and releasable retaining means to retain the sliding sleeve within the desired locations with the housing.

Abstract: A semi-rigid floating spring type centralizer for use in deviated, highly deviated or horizontal well bores, the centralizer comprising a cylindrical tubular housing having a plurality of floating centralizer springs retained thereon.

Abstract: The improved poppet valve of the present invention comprises a simpler and shorter valve which meets or exceeds prior art performance characteristics while being easier and cheaper to make and to fabricate into a float collar or float shoe. The improved poppet valve of the present invention comprises a tubular one-piece body having flange means on the exterior thereof, and a downward-facing valve seat at the bottom interior thereof, with a valve guide spider thereabove. A dome-shaped poppet valve seats on the aforesaid valve seat, and has coaxially secured thereto a upwardly extending stem bolt which protrudes through and above the valve body guide spider. A spring disposed about the stem bolt biases it upwardly, acting on the top surface of the spider and on a lower surface of a spring retention cap secured to the top of the stem bolt. In such a manner, the poppet valve is biased into engagement with the valve body seat at the lower end of the valve assembly.

Abstract: A seal system for a wellhead isolation tool diffuser utilizing elastomeric cup-shaped seals installed on the exterior of the diffuser, which is inserted into the production tubing at the wellhead. After insertion of the diffuser, the production tubing is pressurized, and the seals are set against the interior of the production tubing by the pressure in the well, effecting a tight seal.

Abstract: An access valve for communicating a wire line pressure sensing probe with a subsurface formation of a well to conduct continuously monitored shut in pressure tests on said subsurface formation. The access valve includes a tubular body having a cylindrical inner surface. A first passage communicates the subsurface formation with the cylindrical inner surface of the tubular body. A sliding valve sleeve has a cylindrical outer surface slidably received in said cylindrical inner surface of said tubular body, and has a valve sleeve port disposed through a side wall thereof communicating said cylindrical outer surface of said sliding valve sleeve with a cylindrical inner surface of said sliding valve sleeve. The sliding valve sleeve is slidable between a closed position wherein the valve sleeve port is in fluid isolation from the first passage, and an open position wherein the valve sleeve port is in fluid communication with the first passage.