Patent Application
20190309854
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the presently described embodiments. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present embodiments. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
In order to meet consumer and industrial demand for natural resources, companies often invest significant amounts of time and money in finding and extracting oil, natural gas, and other subterranean resources from the earth. Particularly, once a desired subterranean resource such as oil or natural gas is discovered, drilling and production systems are often employed to access and extract the resource. These systems may be located onshore or offshore depending on the location of a desired resource.
Further, such systems generally include a wellhead assembly through which the resource is accessed or extracted. These wellhead assemblies may include a wide variety of components, such as various casings, valves, fluid conduits, blowout preventers, and the like, that control drilling or production operations. Control systems, such as subsea control pods, can be used to operate hydraulic components and manage flow through the assemblies. When a particular hydraulic function is to be performed (e.g., closing a ram of a blowout preventer), a control valve associated with the hydraulic function can be opened to supply control fluid to the component responsible for carrying out the hydraulic function (e.g., a piston of the blowout preventer). Other valves, such as pressure regulators, can also be used to control flow of fluid within these control systems. Further, such control valves and other valves could also be used to control flow of various fluids in other applications.
Certain aspects of some embodiments disclosed herein are set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of certain forms the invention might take and that these aspects are not intended to limit the scope of the invention. Indeed, the invention may encompass a variety of aspects that may not be set forth below.
Some embodiments of the present disclosure generally relate to valves having articulated seal ring assemblies. In certain embodiments, for example, a valve includes a piston that carries articulated seal ring assemblies for controlling flow through the valve. The articulated seal ring assemblies, which can include shear seal rings and seal ring carriers, are coupled to the piston via joints that allow the shear seal rings to pivot with respect to the piston to facilitate sealing of the shear seal rings against shear seal plates or other surfaces within the valve. In some instances, the articulated seal ring assemblies include separate or integral bearings that facilitate pivoting of the shear seal rings with respect to the piston. And in at least some embodiments, the shear seal rings can pivot independently of one another.
Various refinements of the features noted above may exist in relation to various aspects of the present embodiments. Further features may also be incorporated in these various aspects as well. These refinements and additional features may exist individually or in any combination. For instance, various features discussed below in relation to one or more of the illustrated embodiments may be incorporated into any of the above-described aspects of the present disclosure alone or in any combination. Again, the brief summary presented above is intended only to familiarize the reader with certain aspects and contexts of some embodiments without limitation to the claimed subject matter.
These and other features, aspects, and advantages of certain embodiments will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
Specific embodiments of the present disclosure are described below. In an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
When introducing elements of various embodiments, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Moreover, any use of “top,” “bottom,” “above,” “below,” other directional terms, and variations of these terms is made for convenience, but does not require any particular orientation of the components.
Turning now to the present figures, a well assembly or apparatus 10 is illustrated in
The surface equipment 14 may include a variety of devices and systems, such as pumps, power supplies, cable and hose reels, control units, a diverter, a gimbal, a spider, and the like. Similarly, the riser equipment 16 may also include a variety of components, such as riser joints, flex joints, a telescoping joint, fill valves, and control units, to name but a few examples. The stack equipment 18, in turn, may include a number of components, such as blowout preventers and control systems, that enable control of fluid from the well 12.
In one embodiment generally depicted in
The control pods 26 are connected to the components 28 and 30 by suitable conduits (e.g., control tubing or hoses). This allows the control pods 26 to route hydraulic control fluid to the components 28 and 30 to cause these components to perform their intended functions, such as closing the rams of a blowout preventer or opening a valve. The hydraulic control fluid may be routed to the components 28 and 30 via valves 36. Such valves 36 can include control valves operated by a controller 38 (e.g., a subsea electronics module that controls operation of the control valves based on received command signals). In some instances, one or more of the valves 36 may be provided in the form of a pressure regulator.
More particularly, in at least some embodiments the valves 36 include a pressure regulator and control valves (e.g., solenoid valves) that control flow to hydraulic components 28 and 30, with the pressure regulator and the control valves arranged such that the pressure regulator receives an initial supply pressure from a source of pressurized fluid (e.g., an accumulator bank) and delivers a regulated pressure to the control valves. The initial supply pressure may exceed the pressure rating of the control valves, and the pressure regulator can be used to provide a regulated pressure to the control valves (or other downstream components) that is below their pressure ratings. In at least some embodiments, multiple pressure regulators are used to provide control fluid to downstream components. The multiple pressure regulators could each provide control fluid at the same regulated pressure, or the multiple pressure regulators could be configured such that two or more pressure regulators provide control fluid at different regulated pressures. And while the valves 36 of the presently illustrated embodiment are depicted as components of the stack equipment 18 in
An example of a valve 36 in the form of a pressure regulator 40 is depicted in
During operation, a control medium at a first (supply) pressure, such as a pressure of 3000-5000 psi, may enter the pressure regulator 40 through supply ports 70 and the control medium may be output at a second, regulated pressure, such as a pressure of 200-3000 psi, via at least one regulated-pressure outlet port 72. One such regulated-pressure outlet port 72 is depicted in
The pressure regulator 40 can be spring-loaded, such as by one or more springs (not shown) positioned to bias the piston 52 against fluid pressure (e.g., by pushing the protruding end of the piston 52 in
During operation, fluid pressure within the inner chamber 50 applies a thrust force that causes the piston 52 to move axially within the inner chamber 50 against this biasing force such that the seal rings 56 slide along the seal plates 60 and control flow through the inner chamber 50. The pressure regulator 40 is arranged such that the seal rings 56 do not seal the supply ports 70 when the pressure within the inner chamber 50 is below a lower pressure threshold (e.g., a desired operating pressure for control valves or other downstream components). This allows control fluid to flow into the inner chamber 50 through the supply ports 70 and then out from the inner chamber 50 through the outlet ports 72. The piston 52 moves in response to fluid pressure within the inner chamber 50 and, when the pressure within the inner chamber 50 exceeds the lower pressure threshold, the piston 52 positions two of the seal rings 56 to seal against the seal plates 60 about the supply ports 70 and prevent flow into the inner chamber 50. Other seal rings 56 prevent flow out of the inner chamber 50 through the vent ports 74 until the pressure within the inner chamber 50 exceeds an upper pressure threshold, greater than the lower pressure threshold, and causes the piston 52 to move such that the other seal rings 56 no longer seal against the seal plates 60 about the vent ports 74. This allows excess pressure to escape from the inner chamber 50 through the vent ports 74. Although the seal rings 56 for closing the supply ports 70 can be the same size as those for closing the vent ports 74, in at least some embodiments the seal rings 56 for closing the supply ports 70 are of a different size (e.g., smaller in diameter across their sealing faces) than those for closing the vent ports 74.
The pressure regulator 40 may also include various o-rings or other seals for maintaining pressure within the regulator 40 and preventing leakage. In at least some embodiments, the pressure regulator 40 is a hydraulic pressure regulator and the control medium includes hydraulic fluid. In other embodiments, however, the control medium may be some other material, such as a pressurized gas. And while the presently depicted pressure regulator 40 includes two supply ports 70 and two vent ports 74, with corresponding seal ring assemblies 54 arranged on two opposing sides of the piston 52 to selectively close these supply and vent ports 70 and 74, other embodiments could have some other number of seal ring assemblies 54, supply ports 70, and vent ports 74 in full accordance with the present techniques.
A detail view of two seal ring assemblies 54 carried by the piston 52 is provided in
The sealing surfaces of one or more seal plates 60 (i.e., the surfaces that the seal rings 56 slide along and seal against) may generally be parallel with each other and with the longitudinal axis of travel of the piston 52 and perpendicular to the direction of radial bias applied to the seal rings 56 by the springs 64. In some instances, however, the internal components of the pressure regulator 40 may be misaligned. There may be misalignment between the seal rings 56 and the seal plates 60, or the piston 52 may be rotationally misaligned with respect to the seal plates 60, for example. Manufacturing tolerances or wear can also contribute to misalignment of certain components, such as the piston 52 with respect to the main body 44 or the end cap 46. Further, such misalignment could inhibit proper sealing of the seal rings 56 against the seal plates 60.
In at least some embodiments, however, the pressure regulator 40 (or other valve 36) includes articulated seal ring assemblies 54 with joints 66 that enable the seal rings 56 to pivot to compensate for possible misalignment of internal components. For instance, as depicted in greater detail in
In other embodiments, the joints 66 include integral bearings of seal ring carriers 58. As generally depicted in
In another embodiment generally depicted in
Seals 82 prevent fluid leakage along the exterior of the seal rings 56 while allowing the seal rings 56 to pivot within the sockets 62. Further, the exterior of the seal rings 56 can include one or more recessed portions 90, such as circumferential grooves, to allow a greater range of pivoting motion for the seal rings 56. That is, in contrast to seal rings having straight cylindrical exteriors, the presence of the recessed portions 90 in alignment with the ends of the sockets 62 at the exterior of the piston 52 facilitate pivoting by allowing the recessed portions 90 to receive the outer edges of the sockets 62 (i.e., the edges closest to the seal plates 60) when the seal rings 56 pivot within the sockets 62.
In still another embodiment generally depicted in
From the foregoing description, it will be appreciated that by using the piston 52 to move the seal ring assemblies 54 and allowing the seal ring assemblies 54 to articulate independent of the other seal ring assemblies 54, the seal rings 56 may have increased acceptable angles of misalignment. The increased acceptable misalignment may facilitate proper internal sealing of the pressure regulator 40 (e.g., of the seal rings 56 against seal plates 60) with larger part machine tolerancing, which may allow reductions in individual part costs. In compensating for misalignment, the use of articulating seal ring assemblies 54 in some instances could also help to reduce or avoid certain wear or damage, such as from high contact point loading from binding of internal components during high-velocity dynamic operation.
Finally, the use of articulated seal ring assemblies in a valve may facilitate valve configurations in which some articulated seal ring assemblies are rotationally offset from others such that seal rings of the articulated seal ring assemblies are biased away from a piston in more than two directions. For example, as generally depicted in
The first pair of articulated seal ring assemblies 108 are positioned on the piston 106 opposite one another with their seal rings biased apart toward sealing surfaces within the hollow body 104. The second pair of articulated seal ring assemblies 110 are also positioned on the piston 106 opposite one another but are rotationally offset ninety degrees about the piston 106 with respect to the first pair of articulated seal ring assemblies 108 such that the seal rings of the second pair of articulated seal ring assemblies 110 are biased apart from one another in directions generally transverse to those in which the seal rings of the first pair of articulated seal ring assemblies 108 are biased. In such an arrangement, the articulated seal ring assemblies 108 can each seal against opposing surfaces within the hollow body 104, such as two opposing seal plates, while the articulated seal ring assemblies 110 can each seal against different opposing surfaces within the hollow body 104, such as two additional opposing seal plates. This allows the valve 102 to use offset flow paths, such as one flow path through flow ports in the upper and lower portions of the hollow body 104 in
While the aspects of the present disclosure may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. But it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.
