Abstract: Aspects of the present disclosure relate to float valve assemblies. The float valve assembly comprises a float sub, a first float valve having an outer housing, and a second float valve having an outer housing. The outer housings of the first and second float valves are coupled together and disposed within the float sub in a stacked configuration.

Abstract: A downhole tool includes a tubular, an inner valve assembly positioned in the tubular, and a body positioned radially between the inner valve assembly and the tubular, the body at least partially made from a bonding agent configured to secure the inner valve assembly in the tubular.

Abstract: A downhole tool includes a generally-cylindrical body at least partially made of a cast material, a valve positioned within the body, a first fin positioned on the body and extending outwards therefrom, and a second fin positioned on the body and extending outwards therefrom. The first and second fins are configured to engage an inside diameter surface of an oilfield tubular and retain a bonding material in an annular region defined radially between the body and the inside diameter surface of the oilfield tubular, and axially between the first and second fins.

Abstract: Disclosed is an intermittent pressure switch for pneumatic valves to control pressure relief valves in oil and gas producing operations by directing the valve to open and close based on pressure parameters (pre)set by the user. This enables oil and gas wells to produce based on formation pressure buildup. The inventive switch consists of a box containing a pressure switch programmable from 0 to 5,000 psi, a 3-port solenoid valve, 24 volt battery system, solar panel, solar control charger, pressure gauge, circuit wiring, and pressure fittings.

Abstract: An adjustable tubular string nose uses axially relatively movable wedge segments to form a variable diameter ring shape using technology described in U.S. Pat. No. 7,128,146 in another context. The nose has a seat around a passage therethrough. After insertion of the nose into a first bore, typically a main bore, the nose is retracted out of the main bore and pressure against a seated bore in the nose expands the nose radially to a degree where re-entry into the main bore is precluded but entry into a lateral bore is still possible. The string advances onto a lateral no-go. This signals surface personnel to pick up and raise pressure to blow the seated ball through the seat to again open the passage in the nose. A seal stack behind the nose in advanced into a lateral seal bore and the treatment can then commence.

Abstract: A floating apparatus for use in a casing string and especially for use in offshore casing operations. The apparatus includes a valve configured such that, when there is a pressure differential across the valve below a predetermined mid-pressure threshold, the valve prevents fluid flow and, when the pressure differential exceeds a predetermined high-pressure threshold, said valve non-resiliently allows fluid flow across the valve.

Abstract: A method of treating production fluid in a wellbore includes deploying a capillary string into the wellbore. The capillary string has a plurality of injection valves. The method further includes pumping treatment fluid through the capillary string and into the wellbore. The injection valves have a cumulative set pressure greater than or equal to a hydrostatic pressure of the treatment fluid.

Abstract: A dual packer for at least partially defining a production zone in a wellbore, the dual packer including a packer body having an up-hole side and a down-hole side. A first through bore and a second through bore each extend through the packer body from the up-hole side to the down-hole side. A first piping extends from the down-hole side of the first through bore and includes a perforated sub adjacent the down-hole side of the packer body. A second piping extends from the down-hole side of the second through bore and is communicably connected to the first piping down-hole of the first perforated sub.

Abstract: Embodiments of the invention relate to an assembly for forming a cased well. The assembly may include an undercut drillable cementing shoe with a casing string connection at a first end. The shoe includes external tubing that forms a second end of the shoe and has a first section defining an enlarged inner diameter relative to a second section of the external tubing. The assembly may also include an earth removal member coupled to the second end of the shoe. The first section of the shoe is disposed between the earth removal member and the second section of the shoe. In another embodiment, the assembly may include a casing string having a first portion with a larger inner diameter than a second portion. The assembly may also include an earth removal member coupled to an end of the casing string. The first portion of the casing string is disposed between the earth removal member and the second portion of the casing string.

Abstract: A bi-directional pipeline tool has a body or location in a pipe. A seal element is mounted on the body, the seal element having oppositely directed seal portions with a first seal portion directed towards a first side of the body and a second seal portion directed towards a second side of the body. A valve is provided in the body, the valve having a first port for communicating with fluid on the first side, a second port for communicating with fluid on the second side, and a third port for providing access to a chamber between the seal element and the body. In use, a pressure differential is developed across the tool between fluid upstream of the tool and fluid downstream of the tool. The valve permitting activation of the downstream seal portion, whichever of the portions is the downstream seal portion, by the upstream fluid pressure.

Abstract: A downhole sealing assembly (10) includes a sleeve (12) comprising a swellable medium (22). The sleeve (12) is mounted on a base pipe (14) and defines a flow path (18) between the sleeve (12) and the base pipe (14).

Abstract: A dual packer for at least partially defining a production zone in a wellbore, the dual packer including a packer body having an up-hole side and a down-hole side. A first through bore and a second through bore each extend through the packer body from the up-hole side to the down-hole side. A first piping extends from the down-hole side of the first through bore and includes a perforated sub adjacent the down-hole side of the packer body. A second piping extends from the down-hole side of the second through bore and is communicably connected to the first piping down-hole of the first perforated sub.

Abstract: The present invention relates to a shoe for wellbore lining tubing and to a method of locating wellbore lining tubing in a wellbore. In particular, but not exclusively, the present invention relates to a shoe for wellbore lining tubing having an improved fluid flow diverter assembly for controlling circulation of fluid in the wellbore.

Abstract: A valve for a well pipe, the valve having the following parts: a valve collar connectable to the well pipe; an index piston coaxially positioned within the valve collar for longitudinal translation within the valve collar between closed, flow-open, and locked-open configurations; a detent in the index piston, wherein the detent restricts fluid flow in a circulation direction through a flow path through the index piston; a spring that biases the index piston toward the closed and locked-open configurations; and a plug of the valve collar that mechanically communicates with the index piston to be in corresponding closed, flow-open, and locked-open configurations.

Abstract: A casing shoe for a casing string that includes an annular body. The annular body includes an annular recess that forms an outer portion and an inner portion, the inner portion forming and extending into an inner bore. The annular recess can accept an end of the casing string such that the casing string extends between the inner and outer portions. The annular body includes a homogenous material. The casing shoe is used in a method of guiding a casing string into a wellbore where the casing shoe is attached to an end of the casing string. Attaching the casing string includes inserting the end of the casing string into the annular recess such that the casing string extends between the inner and outer portions. The casing string is then inserted into the wellbore.

Abstract: A valve for a well pipe, the valve having the following parts: a valve collar connectable to the well pipe; an index piston coaxially positioned within the valve collar for longitudinal translation within the valve collar between closed, flow-open, and locked-open configurations; a detent in the index piston, wherein the detent restricts fluid flow in a circulation direction through a flow path through the index piston; a spring that biases the index piston toward the closed and locked-open configurations; and a plug of the valve collar that mechanically communicates with the index piston to be in corresponding closed, flow-open, and locked-open configurations.

Abstract: A method for cementing a casing in a wellbore, the method having the following steps: attaching a valve to a casing; locking the valve in an open configuration; running the casing and the valve into the wellbore; reverse circulating a cement composition down an annulus defined between the casing and the wellbore; injecting a plurality of plugs into the annulus; unlocking the valve with the plurality of plugs; and closing the valve.

Abstract: A float system for use in cementing a casing in a wellbore. The wellbore is drilled with a drill bit attached to the casing. The drill bit is removed after the wellbore is drilled. The float system is lowered into the casing after the drill bit is removed. The float system includes a packer apparatus with a float apparatus, preferably a float shoe, attached to the end thereof. The packer apparatus is set in the casing to hold the float shoe in position. A bottom cementing plug is placed in the casing and is urged downwardly until it engages the upper end of the packer apparatus. The cement will flow through the packer apparatus and the float apparatus to fill the annulus between the casing and the wellbore.

Abstract: A back pressure valve assembly for use in a well casing string. The valve assembly comprises a housing with a stationary and a floating plate therein. The floating plate is moveable between an open position spaced from the stationary plate and a closed position engaging the stationary plate. Fluid flow downwardly through the valve assembly tends to move the floating plate toward the open position, and fluid flow upwardly through the valve assembly tends to move the floating plate toward the closed position. A finger or key may be used to prevent rotation of the floating plate with respect to the housing.

Abstract: A float apparatus for use in a casing string. The float apparatus includes an outer case having a check valve positioned therein. A body portion which may be comprised of high compressive strength cement affixes the check valve to the outer case. The check valve includes a valve body and a valve element. The valve body defines a valve seat and the valve element is deformable so that it will conform to the shape of the valve seat and seal against flow in the casing.

Abstract: An apparatus and method for cementing a casing string in a wellbore. A self-filling tubular cementing collar connected to the lower end of a casing string is provided with one-way flow valving that allows well fluid to enter and self-fill the casing string as it is lowered into the wellbore and automatically prohibits reverse fluid flow from the collar when washing or cementing during forward circulation through the collar. The one-way valving is carried by an axially movable support that can be shifted by a cementing plug moved by pump pressure to permanently seal the entry flow passage after the casing sting is properly positioned in the wellbore.

Abstract: Methods and apparatus for creating a downhole buoyant casing chamber. The buoyant casing chamber may be created after the casing has been at least partially run into the wellbore. Some embodiments also allow circulation of fluid as the casing is being run after the creation of the buoyant chamber. A method of the invention comprises running a length of casing into the well to a first step, forming a buoyant chamber in the casing, filling the chamber with buoyant fluid, either a gas or a light liquid, and running the casing to a second depth greater than the first depth. The apparatus used comprises a length of casing, a floating device disposed in a lower end of the casing and forming a lower boundary of a buoyant chamber, a packer for sealingly engaging the casing in an upper end of the buoyant chamber, and a volume of buoyant fluid to fill the chamber.

Abstract: A differential float and cementing valve assembly used to position and cement casing in a wellbore. A leaf spring and other components of the assembly are preferably constructed of composite materials and/or plastics that can be drilled up with polycrystalline diamond compact (PDC) bits. The valve components may be contained within a metallic housing.

Abstract: The present invention relates to a float collar apparatus for regulating the passage of fluid through a drilling/production liner or sub-sea casing. Apparatus of the present invention is fabricated using plastic flapper valves and valve-actuating sleeve components in contrast to prior art float collar components which are fabricated almost entirely of hard metals. Particularly, the plastic may be nylon, phenolic, or a phenolic-nylon laminate. The use of plastic components in the float collar apparatus of the present invention provides a substantial reduction in time and resources expended during drilling out of the float collar once cementing operations are completed. Additionally, the float collar apparatus of the present invention is fabricated from a pre-determined combination of plastic components and metal components thereby ensuring that the improved float collar can still endure substantial hydrostatic stresses encountered during casing liner running in and cementing operations.

Abstract: The present invention relates to a float collar apparatus for regulating the passage of fluid through a casing liner or sub-sea casing. Apparatus of the present invention is fabricated using plastic flapper valves and sleeve components in contrast to prior art float collar components which are fabricated almost entirely of hard metals. The use of plastic components in the float collar apparatus of the present invention provides a substantial reduction in time and resources expended during drilling out of the float collar once cementing operations are completed. Additionally, the float collar apparatus of the present invention is fabricated from a pre-determined combination of plastic components and metal components thereby ensuring that the improved float collar can still endure substantial hydrostatic stresses encountered during casing liner running in and cementing operations.

Abstract: A float shoe/collar apparatus and method for multi-purpose use in running a tubular string such as a casing string or liner into a wellbore and for optimizing cementing operations. In one presently preferred embodiment, the apparatus permits auto filling of the tubular string as the string is lowered into the wellbore. Circulation can be effected through down jets for washing the wellbore as necessary. After the tubular string is positioned, the down jets can be blocked off and up jets opened to thereby direct cement upwardly to optimize cement placement. Check valves can also be activated to prevent flow from the wellbore into the tubular string. In one embodiment, the apparatus comprises an inner member and tubular member. The inner member is movable upon release of shear pins to cause longitudinal movement relative to the outer member. The movement of the inner member may close a plurality of downward jets and may also open a plurality of upward jets, if desired.

Abstract: A check enhancer for use in a well comprises an outer housing portion and an inner injector portion disposed in the housing portion. The housing portion includes an outer body defining a fluid cavity therein with a plurality of body ports in communication with the fluid cavity and an adapter which slidably receives a portion of a length of tubing therethrough. A tubing fitting connects the tubing to the adapter. The injector portion includes a check valve and a dispersement nipple attached thereto. The check valve is connected to the tubing in the fluid cavity by another tubing fitting, and the check valve allows fluid flow from the tubing through nipple ports defined in the dispersement nipple. The nipple ports are longitudinally spaced from the body ports so that the fluid cavity remains substantially filled with fluid with the dispersement nipple substantially submerged within the fluid.

Abstract: The present invention generally relates to a plunger-type valve for use in a wellbore. The plunger-type valve is arranged to selectively allow fluid flow to enter and exit the valve in both directions. Subsequently, the plunger-type valve can be deactivated to selectively allow fluid flow in only one direction. The valve includes a body, at least one locking segment, a locking sleeve, at least one biasing member, a valve seat and a plunger.

Abstract: Methods and apparatus for creating a downhole buoyant casing chamber. The buoyant casing chamber may be created after the casing has been at least partially run into the wellbore. Some embodiments also allow circulation of fluid as the casing is being run after the creation of the buoyant chamber. A method of the invention comprises running a length of casing into the well to a first step, forming a buoyant chamber in the casing, filling the chamber with buoyant fluid, either a gas or a light liquid, and running the casing to a second depth greater than the first depth. The apparatus used comprises a length of casing, a floating device disposed in a lower end of the casing and forming a lower boundary of a buoyant chamber, a packer for sealingly engaging the casing in an upper end of the buoyant chamber, and a volume of buoyant fluid to fill the chamber.

Abstract: The present invention provides a downhole cementing apparatus run into a borehole on a tubular. The apparatus is constructed on the pipe in such a way that pressure surge during run-in is reduced by allowing fluid to enter the pipe and utilize the fluid pathway of the cement. In one aspect of the invention, an inner member is provided that filters fluid as it enters the fluid pathway. In another aspect of the invention, various methods are provided within the cementing apparatus to loosen and displace sediment in the borehole prior to cementing.

Abstract: A differential float and cementing valve assembly used to position and cement casing in a well bore. A leaf spring and other components of the assembly are preferably constructed of composite materials and/or plastics that can be drilled up with polycrystalline diamond compact (PDC) bits.

Abstract: A downhole cementing system employing a cement choke within the casing to reduce the downward velocity of cement through the casing and thereby inhibit formation fracturing caused by vibration of the casing. The cement choke includes a tubular body defining a fluid passageway, a seat coupled to the tubular body and defining a seat orifice, a choke element coupled to the seat and restricting flow through the seat orifice, and a check valve coupled to the seat and operable to substantially block fluid flow through the seat orifice.

Abstract: The present invention relates to a wiper plug and internal drop ball mechanism that may be used in conjunction with a downhole surge reduction tool to run, hang, and cement casing liners in a wellbore. The apparatus of the present invention comprises a wiper plug assembly removably attached to the drill string within the casing liner, a drop ball sub attached below the wiper plug assembly which releases a float valve actuator ball having a diameter larger than the drill string, and float equipment having a plurality of flapper valves. The apparatus of the present invention may further comprise a diverter tool connected between the drill string and the casing liner.

Abstract: Methods and apparatus for creating a downhole buoyant casing chamber. The buoyant casing chamber may be created after the casing has been at least partially run into the wellbore. Some embodiments also allow circulation of fluid as the casing is being run after the creation of the buoyant chamber. A method of the invention comprises running a length of casing into the well to a first step, forming a buoyant chamber in the casing, filling the chamber with buoyant fluid, either a gas or a light liquid, and running the casing to a second depth greater than the first depth. The apparatus used comprises a length of casing, a floating device disposed in a lower end of the casing and forming a lower boundary of a buoyant chamber, a packer for sealingly engaging the casing in an upper end of the buoyant chamber, and a volume of buoyant fluid to fill the chamber.

Abstract: An improved float valve according to the present invention includes a packer 10 for positioning within a joint of the casing C while at the surface of the well, the packer including a float valve receptacle therein for at least partially receiving a float valve. The float valve body includes a valve seat 56 and a valve member 54 is positioned for selective engagement and disengagement with the valve seat. A guide nose 58 may be optionally provided for positioning within the casing joint between the valve body and the pin end of the casing joint. The float valve body may be reliably fixed and sealed to the packer body. After the packer setting operation, the casing joint and the packer and the float valve may then be positioned as an assembly within the well.

Abstract: The present invention relates to a wiper plug and internal drop ball mechanism that may be used in conjunction with a downhole surge reduction tool to run, hang, and cement casing liners in a wellbore. The apparatus of the present invention comprises a wiper plug assembly removably attached to the drill string within the casing liner, a drop ball sub attached below the wiper plug assembly which releases a float valve actuator ball having a diameter larger than the drill string, and float equipment having a plurality of flapper valves. The apparatus of the present invention may further comprise a diverter tool connected between the drill string and the casing liner.

Abstract: A downhole cementing system employing a cement choke within the casing to reduce the downward velocity of cement through the casing and thereby inhibit formation fracturing caused by vibration of the casing.

Abstract: A differential float and cementing valve assembly used to position and cement casing in a well bore. A poppet valve mounted in the flapper gate of a check valve provides a regulated back-flow of drilling fluid through the check valve. A leaf spring biases the poppet valve to its closed position. Drilling fluid pressure in the well bore overcomes the spring force to open the poppet valve and permit drilling fluid to back-flow into the casing. The regulated admission of drilling fluid into the casing permits the casing to sink into the well at a controlled rate while automatically maintaining a desired level of drilling fluid in the casing. With the casing at the bottom of the well, a cement slurry is pumped through the casing. A setting ball moving in advance of the cement slurry deactivates the poppet valve and its flapper gate and activates a second check valve in the assembly to prevent cement back-flow.

Abstract: A well screen cover including a channel running along substantially the entire length of the well screen cover. The channel may be formed directly into the cover or separately formed and welded to the cover. The channel is open to the exterior of the well screen cover and is formed to house a cable, such as a fiber optic cable, which is run into a well bore along with the well screen.

Abstract: An improved float shoe/collar apparatus is provided for use during casing run in or floated in. The apparatus has an inner tubular member and outer tubular member, movable upon release of shear pins to cause longitudinal movement relative to each other. The movement of the inner tubular member closes a plurality of downward jets and opens a plurality of upward jets. The apparatus also is equipped with a set of check valves, held open on run in, and activated to close upon cementing to prevent “u-tubing” of fluid back into the casing.

Abstract: A tool string, such as one used for performing fracturing operations or other types of operations, includes a valve, a valve operator, and a sealing assembly that in one arrangement includes packers to define a sealed zone. The tool string is carried on a tubing, through which fluid flow may be pumped to the sealed zone. The valve operator is actuated in response to fluid flow above a predetermined flow rate. When the flow rate at greater than the predetermined flow rate does not exist, the valve operator remains in a first position that corresponds to the valve being open. However, in response to a fluid flow rate at greater than the predetermined flow rate, the valve operator is actuated to a second position to close the valve.

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 downhole cut-off valve used for cementing a casing string, comprising: an outer hollow body, having a top end connected at the lower end of the casing string, an inner hole, an inner surface and a projecting shoulder forming on the inner surface and extending inwardly; an inner hollow body, arranged slidably in said outer hollow body and having an inner hole, a wall with a plurality of through holes and a projection forming on the wall and below the through holes and extending outwardly, the projection being adapted to fit with the projecting shoulder of said outer body to define a preliminary position of said inner body with respect to said outer body; the longitudinal positions of the through holes and the projection being arranged in such a manner that the projecting shoulder of said outer body is located therebetween when said inner body is placed in said outer body and will at least partially cover the through holes in response to the movement of said inner body; a relief member, blocking the upper end

Abstract: A float valve 10 includes a valve body 12 for sealing engagement with a float sub 20 having threads for threaded engagement with an oilfield tubular. A valve element 40 includes a stem 50, 70 and a valve cone 52, 80 secured thereto. The valve cone is configured for sealing engagement with a seat 58 on the valve body. An elastomeric seal 48 may also be provided for sealing engagement with the valve body. The stem 50, 70 and the cone 52, 80 are preferably interconnected by a shrink-fit operation, wherein the cone is heated so that a cylindrical recess within the cone expands, while at least a front end 52, 72 of the stem 50, 70 is cooled so that its diameter is reduced. The shrink-fit operation forms a surprisingly reliable interconnection of a float valve stem with a cone, and substantially increases the life of the downhole float valve.

Abstract: A system for selective production from, and stimulation of, subterranean production zones while improving productivity and enhancing control of the well. Portions of a production tubing string and an internal stimulation/shifter string are assembled and run together as completion segments. Consecutive completion segments, with each segment including packers that surround sleeves and terminate at the upper end in a well control valve, are run into the cased wellbore so that the acid flow ports operated by sleeve valve assemblies are placed proximate the perforations of prospective production zones. The production zones are then stimulated as the stimulation/shifter string is moved progressively outward placing acid at each consecutive zone. The stimulation/shifter string is then removed from the production tubing string, mechanically closing the well control valve assembly by tubing manipulation.

Abstract: The present invention provides an apparatus in the form of a float shoe or collar for use in cementing a casing string within a well bore. The shoe or collar has blades extending therefrom for centering the shoe or collar, as well as the lower end of the casing string, within the well bore. The blades include jetting ports positioned therein for use in jetting the formation. In an alternative embodiment, the jetting ports are located between blades which are generally convoluted and extend circumferentially part-way around the perimeter of the apparatus.

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 float valve 10 includes a valve body 12 for sealing engagement with a float sub 20 having threads for threaded engagement with an oil field tubular. A valve element 40 includes a stem 50, 70 and a valve cone 52, 80 secured thereto. The valve cone is configured for sealing engagement with a seat 58 on the valve body. An elastomeric seal 48 may also be provided for sealing engagement with the valve body. The stem 50, 70 and the cone 52,80 are preferably interconnected by a shrink-fit operation, wherein the cone is heated so that a cylindrical recess within the cone expands, while at least a front end 52, 72 of the stem 50, 70 is cooled so that its diameter is reduced. The shrink-fit operation forms a surprisingly reliable interconnection of a float valve stem with a cone, and substantially increases the life of the downhole float valve.

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: Floating apparatus for well casing including a check valve disposed in a sleeve, wherein the sleeve is receivable within an outer case. In the case of a float collar, the outer case comprises coupled upper and lower casing string sections; while in the case of a float shoe, the outer case is individually coupled to a lower casing string section. The valve includes a valve housing, wherein a first cement body portion attaches the valve housing to the sleeve. When the embodiment of the invention is constructed as a float collar, the sleeve includes an annular flange that is outwardly extended therefrom and is received between ends of coupled upper and lower casing string sections for holding the sleeve and affixed valve within the outer case. A seal is provided between the flange and upper casing string section.