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: The present invention relates to a gel hydration tank and method for hydrating gels for use in oil well treatment operations according to which a mixture of water and gel is introduced into the interior of the tank and flows through the tank before being discharged from the tank, whereby specific devices are used to deflect and/or re-direct fluid flow so as to increase the distance traveled for a given fluid volume element, which consequently increases the plug flow efficiency of the tank.

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: The current invention provides a process and apparatus for determining the density of a flowing fluid without requiring knowledge of the fluid's Theological properties. The process of the current invention is capable of providing continuous “real time” analysis of fluid density. The apparatus of the current invention comprises at least two pressure assessment zones fitted with fluid pressure sensing points. Pressure sensing devices connected to the pressure sensing points provide the data necessary to enable the calculation of fluid density.

Abstract: A method and apparatus for generating foam cement and placing foam cement in an annulus between a casing and a wellbore. The method includes the steps of displacing cement downwardly in the casing and injecting a gas, preferably nitrogen, into the cement at a predetermined location downhole in the casing. The nitrogen may be injected through a ported sub. The ported sub may be connected in a tubing string that is lowered in the casing. The ported sub has a plurality of ports, which may have nozzles connected therein, that communicate a central opening through the ported sub with an annulus between the ported sub and the casing. The rate at which nitrogen is injected into the cement preferably increases from a leading edge of the cement to a trailing edge of the cement so that a consistent foam cement quality is achieved.

Abstract: A running tool for wiper plugs used in cementing well casings into a wellbore. The running tool and setting balls or darts used to launch the plugs are retrievable following deployment of the plugs. Flapper valve assemblies on the wiper plugs are activated after the plugs are displaced from the running tool to eliminate the requirement to maintain a setting ball or dart in engagement with the wiper plug as the assembly is pumped down the well casing. Because of being retrievable, the mandrel, setting sleeves and setting ball or dart may be constructed of any desirable high-strength material without regard to the need to drill up the material following completion of the cementing job. The use of high-strength steel permits large flow passages to be employed in the cementing plugs by eliminating the need for large volumes of drillable metals in the plugs. The running tool protects the flapper valve seal surfaces from circulating fluids prior to deployment of the plugs from the tool.

Abstract: A device and a method for testing a viscosified fluid containing particulate indicate when the particulate is in suspension within the fluid and when it is not. The device and method stir the fluid and particulate mixture for a time during which the viscosity of the fluid changes such that during a first period of the stirring time substantially all the particulate remains suspended in the fluid and during a second period of the stirring time substantially all the particulate settles out of suspension in the fluid. A signal is generated during the first and second periods such that the signal has a characteristic that changes from the first period to the second period to indicate the change in particle carrying ability of the fluid. Other characteristics, including crosslinking time, can also be determined. A test chamber includes interacting projections extending from the inner surface of a cup receiving the fluid and from an axial support extending into the fluid in the cup.

Abstract: A system and method for transferring pipe according to which a pipe joint is positioned in a pipe lift in a first position and moved to a second position before being transferred from the pipe lift to a pipe shuttle and moved to a third position.

Abstract: A flow assurance system includes an inner pipe disposed within an outer pipe to assure flow through the outer pipe. During installation and relative axial movement with the outer pipe, the inner pipe is nearly neutrally buoyant or fully neutrally buoyant in the fluids of the outer pipe and may extend partially or completely through the outer pipe. The inner pipe may be anchored at one end within the outer pipe. The inner pipe is preferably composite coiled tubing that is installed using a propulsion system. The system may allow fluids to flow through the inner pipe and commingle with the fluids in the outer pipe or may flow fluids through the inner pipe to the exterior of the outer pipe. Hot fluids may pass through the inner pipe to maintain the temperature of the fluids flowing through the outer pipe and chemicals may flow through the inner pipe to condition the fluids in the outer pipe. Tools may be attached to the end of the inner pipe for conducting flow assurance operations within the outer pipe.

Abstract: An embodiment of a downhole tool for use with a workstring in a wellbore includes a first section, a second section, and a coupling mechanism adapted such that in a first configuration the coupling mechanism couples the first section to the second section. In a second configuration, the coupling mechanism does not couple the first section to the second section. Also disclosed is a method for creating a plug in a wellbore, the method comprising: injecting a slurry into the workstring to form a plug in the wellbore, positioning a flow preventing mechanism into the workstring to prevent fluid flow from exiting the workstring, inducing a coupling mechanism to uncouple a portion of the workstring such that the portion remains with the slurry to create the plug in the wellbore, and removing the first section from the wellbore.

Abstract: A well tool assembly interconnection method is provided. In a described embodiment, a continuous tubing string has connectors positioned corresponding to desired locations for tool assemblies in a well. The tubing string is wrapped on a reel and transported to a well. As the tubing string is deployed from the reel into the well, the tool assemblies are interconnected between the connectors.

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: Apparatus and method for controlling an unswept volume in a piston system. The method includes rotating a shaft around a rotation point to drive a piston within a cylindrical volume in a periodic manner, modifying the stroke length of the piston, and moving the center of the shaft relative to the cylindrical volume such that a change in an unswept volume or compression ratio is controlled.

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: A coiled tubing injector apparatus for use in inserting coiled tubing into a well, temporarily suspending the coiled tubing, and removing the coiled tubing from the well is described. The apparatus includes a base with a pair of spaced-apart carriages extending upwardly therefrom. The base is part of a frame positioned above a wellhead. The carriages each have a gripper chain drive system rotatably mounted thereon and movable therewith. An actuation and linkage system allows the carriages to move toward and away from one another in a lateral or transverse direction with respect to the superstructure and the base. Thus, the gripper chain systems comprises gripper chains that can be engaged or disengaged from the coiled tubing extending through the apparatus. A wetting fluid basin is positioned below the gripper chains, and support guides engage the coiled tubing below the gripper chains to prevent buckling of the coiled tubing.

Abstract: A tubing guide for directing coiled tubing through an injector apparatus and into a well. The tubing guide comprises a frame, which is also referred to as a tubing carrier, extending from a base. The shape of the tubing guide changes depending upon the natural radius of curvature of the tubing. The tubing carrier will conform to provide a path for the coiled tubing that more nearly approximates the residual radius of curvature of the coiled tubing. The carrier has a plurality of segments pivotably connected to one another. The segments can pivot and thus the carrier itself can move from a fully retracted position to a fully rotated position. In the fully rotated position, the carrier can approximate a radius larger than that in the fully closed position. The segments are allowed to pivot or rotate as the tubing is passing therethrough so that the shape of the carrier is continually adjusting so as to provide a more natural path for the coiled tubing.

Abstract: An improved downhole tool apparatus for limiting the extrusion of a packer element. The apparatus includes a packer mandrel having a packer element assembly disposed in a wellbore. Packer retaining shoes are disposed about the packer mandrel at the ends of the packer element assembly. The packer retaining shoes have an inner retainer and an outer retainer. The inner retainer has a plurality of segments having gaps therebetween that expand in width when the retaining shoe is moved from an initial position in which it is disposed about the packer mandrel to an expanded position wherein it engages the wellbore to limit the extrusion of the packer element assembly. The outer retainer is likewise made up of a plurality of segments having gaps therebetween that will expand. The inner retainer segments cover the gaps that exist between the outer retainer segments and the outer retainer segments cover the gaps that exist between the inner retainer segments so that extrusion is limited.

Abstract: This invention relates to a dual jacking system and method for inserting and extracting tubulars, or the like into and out of a well, such as an oil or gas well, at a relatively high rate of speed.

Abstract: A wellhead isolation tool comprises a threaded drive rod coaxially aligned with a tubular mandrel having a smooth outer surface. A motor displaces the threaded drive rod vertically without rotating the drive rod to move the tubular mandrel through a wellhead into a tubular element in a well. The lower end of the tubular mandrel will sealingly engage the tubular element in the well so that treating fluids or other substances such as, but not limited to, chemicals and erosive flows, can be displaced therethrough at high pressures into the well to fracture or otherwise treat the well without damaging the wellhead.

Abstract: A plug valve and fluid control method according to which a cylindrical plug is provided in a bore of a body member and has a through passage formed therein. The plug is adapted to be rotated about its axis to move the passage between an open position in which it is in alignment with passages in the body member to permit fluid flow through the body member, and a closed position in which it is out of alignment with the passages to prevent the fluid flow.