CN-122029371-A - Capturing escaping fluid on a safety valve

Abstract

A seal is configured to reduce a leak rate on a safety valve. These configurations may direct the escape material through a tortuous flow path that may significantly dissipate the amount of flow exiting the device. Such tortuous flow paths may include features, such as undulations or loops, that may affect the flow in a manner that achieves these outlet parameters of the flow.

Inventors

• R. Krishvasan

Assignees

• 德莱赛有限责任公司

Dates

Publication Date

20260512

Application Date

20241011

Priority Date

20231013

Claims (20)

1. 1. A safety valve, the safety valve comprising: A preload unit configured to generate a load; a closure member under the influence of said load; A seat proximate the closure member, wherein the closure member and the seat are configured to contact one another to form a seal in a closed position, and A leakage capture unit disposed outside of the seal and including a flow path to receive a flow of material exiting the seal.
2. 2. The safety valve of claim 1, wherein a leak capture surrounds the seal.
3. 3. The safety valve of claim 1, wherein the leak capture device is part of the seal.
4. 4. The safety valve of claim 1, wherein the flow path has a tortuous geometry.
5. 5. The safety valve of claim 1, wherein the flow path comprises a series of undulations.
6. 6. The safety valve of claim 1, wherein the flow path is configured to create a vortex-like flow.
7. 7. The safety valve of claim 1, wherein the flow path is configured with a region for containing material flowing in a vortex.
8. 8. The safety valve of claim 1, wherein the flow path comprises a fluid logic structure.
9. 9. The safety valve of claim 1, wherein the flow path comprises a fluid diode.
10. 10. The safety valve of claim 1, wherein the flow path comprises a series of fluid diodes.
11. 11. A valve, the valve comprising: A seat; A closure member movable relative to the seat, the closure member having a position in contact with the seat, the position forming a contact interface, and A leakage capture unit surrounding the contact interface, the leakage capture unit comprising a flow path terminating at a first opening and a second opening on either end respectively, Wherein the flow path is configured to block flow such that less flow enters at the first opening than exits at the second opening.
12. 12. The valve of claim 11, wherein the flow path causes the flow to form a vortex.
13. 13. The valve of claim 11, wherein the flow path redirects and mixes a portion of the flow with the flow in the flow path.
14. 14. The valve of claim 11, wherein the flow path follows a non-linear direction radially away from the contact interface.
15. 15. The valve of claim 11, wherein the flow path is perpendicular to an axis of the closure member.
16. 16. The valve of claim 11, wherein the leakage capture unit comprises a fluid diode disposed along the flow path.
17. 17. The valve of claim 11, wherein the leakage capture unit comprises a loop having an inlet and an outlet, the inlet and the outlet each coupled with a passageway such that a portion of flow from the passageway enters through the inlet and exits through the outlet in a direction opposite to flow in the passageway.
18. 18. A method, the method comprising: Receiving a flow into a passageway adjacent to a contact interface found between a closure member and a seat in a valve, and The flow in the passageway is directed in a manner that prevents the flow such that the flow entering the passageway is less than the flow exiting the passageway.
19. 19. The method of claim 18, the method further comprising: a seal is provided around the contact interface, the seal including the passageway.
20. 20. The method of claim 18, the method further comprising: a seal is provided around the contact interface, the seal including the passageway extending radially away from the contact interface.

Description

Capturing escaping fluid on a safety valve Cross Reference to Related Applications The present application claims the benefit of U.S. patent serial No. 18/913,140, filed on 10/11/2024, entitled "CAPTURING ESCAPING FLUID ON A SAFETY VALVE (capturing of escaping fluid on a safety valve)", which claims the benefit of priority of U.S. patent serial No. 63/590,021, filed on 10/13/2023, entitled "CAPTURING ESCAPING FLUID ON A SAFETY VALVE (capturing of escaping fluid on a safety valve)". The contents of these applications are incorporated by reference herein in their entirety. Background Flow controls play an important role in many industrial facilities. For example, power plants and industrial process facilities use different types of flow controls to manage the flow of material (typically fluid) throughout a vast network of pipes, tanks, generators, and other equipment. Safety relief valves are "fail-safe" devices that protect against rapid increases in pressure on lines in these networks. These devices, also known as "safety" valves or "pressure relief" valves, are necessary to avoid "over-pressure" conditions that may damage parts of the equipment or facility. The safety valve may use different mechanisms to generate a closing or "biasing" force to maintain its closing member in contact with its seat. The seal created in this "valve seat area" prevents material flow unless a system pressure spike occurs that overcomes the "set point" to open the valve. A pilot operated relief valve (POSRV) often uses system fluid under control of a fluid control module to trigger operation between its closed position and its open position. In other arrangements, coil springs and the like may generate the biasing load. However, it has been found that even in response to system pressure below the set point of the device, material may leak through the seal at the valve seat area. Also, the density or other properties of the material may cause or exacerbate leakage. For example, compressible fluid may leak more than incompressible fluid because compressible fluid has a lower density than incompressible fluid. Disclosure of Invention The subject matter of the present disclosure relates to improvements to flow controls. Of particular interest are embodiments that can prevent or trap material leaking from the valve seat area of the device. These embodiments may direct leakage into flow paths configured to mitigate flow and thus reduce the rate of leakage from the valve seat area, or even eliminate leakage entirely. These configurations may include tortuous or serpentine geometries, for example, labyrinth-type designs that create recirculation zones throughout their length. Other arrangements may reverse or redirect the leakage flow to prevent material from escaping from the seal or valve seat area. These configurations may employ geometries, such as fluid diodes, that may bias flow in only one direction, or may reverse the direction of flow when used herein to prevent fluid from escaping from the device. Drawings The present description makes reference to the accompanying drawings: FIG. 1 depicts an exemplary embodiment of a leak capture unit for use in a safety valve; FIG. 2 depicts an example of the structure of the leakage capture unit of FIG. 1; FIG. 3 depicts an example of the structure of the leakage capture unit of FIG. 1; FIG. 4 depicts a plot of data corresponding to an example computational fluid dynamics analysis of a metal-to-metal seal; FIG. 5 depicts a plot of data corresponding to an example computational fluid dynamics analysis of a metal-to-metal seal; FIG. 6 depicts a plot of data corresponding to an example computational fluid dynamics analysis of the leakage capture unit of FIG. 2; FIG. 7 depicts a plot of data corresponding to an example computational fluid dynamics analysis of the leakage capture unit of FIG. 3, and Fig. 8 depicts a perspective view of an exemplary structure of the safety valve of fig. 1. The drawings and any description herein represent examples in which the present invention may be disclosed or explained. These examples include the best mode and also enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The drawings are not to scale unless the discussion otherwise indicates otherwise. Elements in an example may appear in one or more of several views or in a combination of several views. The same reference numbers may be used in the drawings to refer to the same or corresponding elements. The methods are merely exemplary and may be modified by, for example, reordering, adding, deleting, and/or altering individual steps or stages. The singular forms "a," "an," and "the" are intended to include the plural forms of any such names and any such items, components, elements or functions, unless the specification explicitly states or otherwise states such exclusions. Likewise, any reference to "one emb