Apparatus and method for selective flow control

[0001] This application claims priority from U.S. Provisional Patent Application Ser. No. 61/324,061, filed Apr. 14, 2010, the disclosure of which is incorporated herein by reference in its entirety.

[0002] This disclosure pertains generally to flow control devices such as valve.

[0003] During the drilling and completion of oil and gas wells, the downhole environment can impose substantial operational stresses on downhole equipment. These harsh conditions include vibration and torque from the drill bit, exposure to drilling mud, drilled cuttings, and formation fluids, hydraulic forces of the circulating drilling mud, and scraping of sensitive equipment against the sides of the borehole. Extreme pressures and temperatures may also be present. Such harsh conditions can damage and degrade downhole equipment. Valves used in drilling operations may be susceptible to the harsh downhole conditions because they require the use of seals and moving parts. Valves that interact with the drilling mud flow may be susceptible to the drilling mud, the deleterious debris carried by the drilling mud, and significant pressure drops.

[0004] The present disclosure addresses the need for sealing high differential pressure in a downhole environment, as well as in surface applications.

[0005] In aspects, the present disclosure provides an apparatus for controlling a fluid flow. The apparatus may include a body having a fluid conduit; and a disk member selectively blocking flow across the fluid conduit. The disk member may include a shaft having a longitudinal axis; a ring member disposed on the shaft; sealing member disposed on the shaft; and a pressure applying surface in contact with the sealing member. The pressure applying surface may be non-orthogonal to the longitudinal axis.

[0006] In aspects, the present disclosure also provides an apparatus for controlling a fluid flow. The apparatus may include a body having a fluid conduit formed of a first section and a second section; a rod configured to translate in the body, the rod having a flow passage in communication with the first fluid conduit section; a first and second sleeve members disposed in the body, each sleeve member having a bore in communication with the second fluid conduit section; and a disk member disposed in the rod and between the first and second sleeve members. The disk member may include a shaft having a longitudinal axis and a medial flange; a sealing member disposed on the shaft and on each side of the medial flange; a pressure applying surface in contact with each sealing member, wherein the pressure applying surfaces are non-orthogonal to the longitudinal axis; and a ring member disposed on each end of the shaft, each sealing member being positioned between an associated ring member and pressure applying surface.

[0007] In aspects, the present disclosure may include a method for controlling a fluid flow. The method may include moving a disk member to selectively block flow across a fluid conduit formed in a body. The disk member may include a shaft having a longitudinal axis; a ring member disposed on the shaft; a sealing member disposed on the shaft; and a pressure applying surface in contact with the sealing member, wherein the pressure applying surface is non-orthogonal to the longitudinal axis.

[0008] In aspects, the present disclosure provides devices, systems and method for enhanced control, operation, service life, reliability, and/or performance for flow control devices. The teachings may be applied to a variety of systems both in the oil and gas industry and elsewhere.

[0015] Referring initially to FIGS. 1 and 2, there is shown a valve assembly 10 that may be used to provide bi-directional flow control. The valve assembly 10 may include a body or housing 20 in which a cage 30, a rod 40, and a disk member 50 are disposed. As will be described in greater detail below, the valve assembly 10 may be configured to control fluid flow across flow conduits 22 and 24.

[0016] In one embodiment, the disk member 50 selectively blocks fluid communication between a flow bore 32 in a cage 30 and flow passages 42 formed along the rod 40. In the embodiment shown, the flow bore 32 connects to flow conduit 22 and the flow passages 42 connect to flow conduit 24. In FIG. 1, the valve assembly 10 is shown in the closed position wherein the disk member 50 forms a barrier that blocks fluid communication between the flow bore 32 and the flow passages 42. In FIG. 2, the valve assembly 10 is shown in the open position wherein the disk member 50 has shifted to hydraulically connect the flow bore 32 and the flow passages 42. Exemplary flow paths are designated with numerals 44. It should be noted that the flow paths 44 are bidirectional.

[0017] As shown in FIG. 1, in one embodiment, the disk member 50 may be shifted between the open and the closed position with the rod 40. The rod 40 is positioned in and translates along a bore 26 of the housing. In one arrangement, the rod 40 is formed as a generally cylindrical member that has a transverse bore 46 for receiving the disk member 50. The rod 40 may have an outer surface on which the flow passages 42 are formed. That is, the flow passages 42 may be slots or reduced diameter portions that form gaps between the housing 20 and the rod 40 and cage 30 and the rod 40 through which fluid may pass. In some embodiments, flow passages may be formed as bores within the rod 40. The rod 40 may be supported in the housing 20 by the cage 30. In one embodiment, the cage 30 may be formed as a tubular or mandrel-like member that is received into a chamber 28 of the housing 20. The cage 30 may include a transverse bore 34 for receiving sleeves 36. The cage may be secured within the housing 20 with a retention member 12 and a securing member 14.

[0018] Referring now to FIG. 3, in one embodiment, the disk 30 may be formed as a member that is received into the transverse bore 46 of the rod 40. The disk member 50 may include a shaft 52 on which a medial flange 54 is formed. The shaft 52 has distal ends 56. Each distal end 56 is shaped to receive a first back-up ring 60 that seats against the flange 54 and a disk 62. The ring 60 may be formed as a member that is annular in shape. In one embodiment, the disk 62 may include inner and outer grooves 64, 66. Inner and outer back-up rings 68, 70 may be positioned in the inner and outer grooves 64, 66, respectively. A sealing element 72, such as an o-ring, may be disposed between the back-up ring 60 and the disk 62. Thus, each sealing member is positioned between an associated ring 60 and a pressure applying surface of the disk 62. While the sealing element 72 is shown as circular, it should be understood that the sealing element 72 may deform into a non-circular shape when compressed between the back-up ring 60 and the disk 62. The several components of the disk member 50 may be sized and shaped to minimize the gap between the disk member 50 and an inner surface 47 (FIG. 1) that defines the bore 46.

[0019] Referring now to FIG. 1, in certain embodiments, one or more surfaces of the valve 10 utilize feature and/or may be treated or formed with one or more materials that increase the ability of the valve 10 to confine fluid flow only along the flow paths 44 (FIG. 2). For example, seal assemblies 80 may be strategically disposed with the valve 10 to control fluid flow. An exemplary seal assembly 80 may include a sealing element 82, such as an o-ring or t-ring, that is positioned between two compression or back-up rings 84.

[0020] Additionally, mating surfaces along in the vicinity of the flow paths 44 may be treated or formed to enhance resistance to fluid invasion, increase resistance to wear, etc. For example, one or more of the outer surfaces of the sleeve 36 may include polycrystalline diamond (PCD), monocrystalline diamond, carbide, cemented carbide, tungsten carbide, hard metal, synthetics, plastic material, metal, monocrystalline aluminium oxide or similar materials. Also, one or more of the outer surfaces of the disks 62 may be formed of polycrystalline diamond (PCD), monocrystalline diamond, carbide, cemented carbide, tungsten carbide, hard metal, synthetics, plastic material, metal, monocrystalline aluminium oxide or similar materials. In certain embodiment, such surface treatments are provided on the mating surfaces of the contact 86 (FIG. 1) between the sleeve 36 and the disk 62.

[0021] Additionally, the disk member 50 of the present disclosure may be susceptible to numerous variants. As shown in FIGS. 3-7, various shapes and arrangements may be used for the back-up ring 60 and/or the shaft 52 to in order to compress the sealing member 72 with a pressure-applying surface that is not orthogonal to the longitudinal axis 90 of the shaft 52. As will become apparent, the back-up rings 60 that seat on the flange 54 (i.e., the interior back-up rings) and/or the flange 54 may use one or more contact surfaces that are non-orthogonal to the axis 90 of the shaft 52. Moreover, either the interior back-up rings 60 or the flange 54 may be omitted for a particular arrangement. In embodiments, the rod 40 shifts or reciprocates the disk 50 transverse to the longitudinal axis 90.

[0022] In FIG. 3, the back-up ring 60 may be formed in a non-rectangular shape: e.g., a quadrangular shape. For example, the pressure applying surface 61 may be non-parallel to an opposing surface 63 and the flange 54 uses a rectangular in cross-sectional shape.

[0023] In FIG. 4, the back-up ring 60 uses a somewhat rectangular shape, but the pressure applying surface 61a is arcuate or concave. The surface 61a may have a contour that is complementary to the sealing element 72, or have a different contour. Also, in other embodiments, the surface 61 may be convex and may include an inflection point (e.g., a convex portion and a straight portion).

[0024] In FIG. 5, the back-up ring 60 may be formed in a non-rectangular shape (e.g., a trapezoid). For example, the pressure applying surface 61b may be non-parallel to an opposing surface 63b. Additionally, the shaft 52 does not include a flange. Rather, the shaft 52 may be shaped in a manner similar to two frusto-conical members that form a central apex 53. Thus, the shaft 52 need not be cylindrical in shape and need not include a flange.

[0025] In FIG. 6, the shaft 52 includes a flange 56a having a generally trapezoidal shape. The flange 56a includes non-parallel pressure applying surface 58a. In this embodiment, the shaft 52 does not include back-up rings seated on the flange 56a.

[0026] In FIG. 7, the shaft 52 includes a flange 56a having a generally trapezoidal shape. A back-up 60 that seats on the flange 56a may be formed as a parallelogram. The back-up ring 60 may include a pressure applying surface 61c that is not orthogonal relative to the longitudinal axis 90 of the shaft 52.

[0027] Referring now to FIG. 8, there is isometrically shown the valve 10. As discussed previously, the valve 10 includes a housing 20 that receives the cage 30, the rod, and the disk member 50. In the embodiment shown, the flow bore 32 connects to flow conduit 22 and the flow passages 42 connect to flow conduit 24. The translation of the rod 40 shifts the disk member 50 between in the open and closed position as described earlier. A variety of mechanisms may be used to move the rod 40. In some embodiments, pressurized hydraulic fluid may be applied the rod 40. In other embodiments, an electro-mechanical device coupled to an end 49 of the rod 40 may be used to reciprocate the rod 40 in the housing 20. Illustrative devices include electric motors, hydraulically-actuated motors, solenoid-type devices, etc.

[0028] Referring to FIG. 9, in one non-limiting embodiment, the valve 10 may be used to create or diffuse a differential pressure between a subsurface environment and an environment in a well tool 100 that has been closed off from the subsurface environment. The subsurface environment may be a borehole 102 that is filled with well fluids. The well tool 100 may be a bottomhole drilling assembly, a fluid sampling tool, a coring tool, or any other tool that is configured or perform one or more tasks (e.g., forming the borehole, sampling/testing formation solids or fluids, etc.) in the borehole 102. In some applications, this may be considered an equalizer-type valve. The valve 10 may be used to isolate or connect an annulus 104 of the borehole with a flowline (not shown) of the valve internal to the well tool 100. The well tool 100 may be conveyed via a work string 106, which may include a rigid carrier (e.g., drill string, casing, liner, etc.) or non-rigid carrier (e.g., wireline, slickline, eline, etc.). When the annulus is isolated from the internal flowline, a significant pressure drop is created on the order of thousands of psi's. If the default position of the valve is to connect the annulus with the internal flowline, then the valve is considered normally open. If the default position is isolation, then the valve is considered normally closed. Disk members or assemblies according to embodiments of the present disclosure enhance internal sealing and, therefore, increase the operating capabilities of the valve 10. In certain embodiments, the valve 10 may be bidirectional and multi-switchable. Moreover, in certain embodiments, in closed position the valve may be zero leakage.

[0029] From the above, it should be appreciated that what has been described includes, in part, an apparatus for controlling a fluid flow. The apparatus may include a body in which a fluid conduit is formed and a disk member that selectively blocks flow across the fluid conduit. The disk member may include a shaft having a longitudinal axis, a ring member disposed on the shaft, a sealing member disposed on the shaft, and a pressure applying surface in contact with the sealing member. The pressure applying surface may be non-orthogonal to the longitudinal axis.

[0030] From the above, it should be appreciated that what has been described also includes, in part, a method for controlling a fluid flow. The method may include moving a disk member to selectively block flow across a fluid conduit formed in a body. The disk member may include a shaft having a longitudinal axis, a ring member disposed on the shaft, a sealing member disposed on the shaft, and a pressure applying surface in contact with the sealing member. The pressure applying surface may be non-orthogonal to the longitudinal axis.

[0031] From the above, it should be appreciated that what has been described further includes, in part, an apparatus for controlling a fluid flow. The apparatus may include a body having a fluid conduit formed of a first section and a second section; a rod configured to translate in the body, the rod having a flow passage in communication with the first fluid conduit section; a first and second sleeve members disposed in the body, each sleeve member having a bore in communication with the second fluid conduit section; and a disk member disposed in the rod and between the first and second sleeve members. The disk member may include a shaft having a longitudinal axis and a medial flange; a sealing member disposed on the shaft and on each side of the medial flange; a pressure applying surface in contact with each sealing member, wherein the pressure applying surfaces are non-orthogonal to the longitudinal axis; and a ring member disposed on each end of the shaft, each sealing member being positioned between an associated ring member and pressure applying surface.

[0032] While the foregoing disclosure is directed to the one mode embodiments of the disclosure, various modifications will be apparent to those skilled in the art. It is intended that all variations be embraced by the foregoing disclosure.