SYSTEM FOR FLUID TRANSFER

Abstract

A fluid transfer system for use with a valve tree at a well, the valve tree having a wellhead axis, may comprise a header having a header flow axis and a coupler connected to the valve tree and the header and providing fluid communication between the valve tree and the header, the coupler having a coupler flow axis. The sum of the direction changes for a fluid flowing from the header into the valve tree may be less than 225°. The coupler may include a coupler inlet, which may be at substantially the same elevation as the header flow axis. The coupler may be connected to the header such that the coupler flow axis intersects the header flow axis or such that the coupler axis passes between the header axis and the surface of the earth. An angle between the coupler flow axis and the wellhead axis may be acute.

Description

RELATED APPLICATION

This application is a nonprovisional application which claims priority from U.S. provisional application No. 63/301,891, filed Jan. 21, 2022, which is incorporated by reference herein in its entirety.

FIELD OF THE DISCLOSURE

This disclosure relates generally to the field of equipment used in fracturing operations.

DESCRIPTION OF THE RELATED ART

In oilfield production operations, some wells may be stimulated to increase the production of hydrocarbons, such as oil and gas. Such techniques may include high-pressure, or hydraulic, fracturing of the well formation, known to the art as “fracing” a well formation. Generally, in this process a fluid, is pumped into the formation surrounding the wellbore at high pressure via an assembly of valves, commonly referred to as a frac tree, and related frac fluid pumping equipment.

BRIEF SUMMARY

The following presents a simplified summary of the disclosed subject matter in order to provide a basic understanding of some aspects of the subject matter disclosed herein.

In an embodiment of the present disclosure, a fluid transfer system for use with a valve tree at a well, the valve tree having a wellhead axis, comprises a header having a header flow axis and a coupler connected to the valve tree and the header and providing fluid communication between the valve tree and the header. The coupler may comprise connectors and a coupler conduit that defines a coupler flow axis.

The fluid flow path from the header to the wellhead may include a plurality of direction changes, with none of the direction changes being 90°. The coupler may include a coupler inlet and the coupler inlet may be at substantially the same elevation as the header flow axis or above the header flow axis. The coupler may be connected to the header such that the coupler flow axis intersects the header flow axis. Alternatively, the coupler may be connected to the header such that the coupler axis passes between the header axis and the surface of the earth. In some embodiments, the angle between the coupler flow axis and the wellhead axis may be less than 90°.

The system may include a valve tree multi-path flow connector in fluid communication with the valve tree and a flow control valve having a flow axis. The flow control valve may be directly coupled to the valve tree multi-path flow connector and in fluid communication with the header, and the connection between the coupler and the valve tree may include the valve tree multi-path flow connector.

The header may include a conduit connected to an inlet through a header multi-path flow connector and an isolation valve. The valve tree may include a master valve and the valve tree multi-path flow connector may be disposed vertically above the master valve. The flow axis of the flow control valve may be substantially perpendicular to the flow axis of the master valve.

The header may further comprise an expansion spool. The system may further comprise an elevating skid positioned beneath the header. The system may further comprise an isolation valve, which may be positioned so as to isolate a section of the header.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is best understood from the following detailed description when read with the accompanying figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily reduced for clarity of discussion.

FIGS. 1 and 2 are two perspective views from opposite directions of a fluid transfer system in accordance with an illustrative embodiment of the invention.

FIG. 3 is a side view of some components of the fluid transfer system of FIG. 1.

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, or examples, for implementing different features of various embodiments. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

“Master valve”—A master valve is a valve located on a valve tree that controls all flow from a wellbore.

“Directly coupled” means connected without intermediate structure.

This application incorporates by reference the teachings of U.S. Publication Number application Serial No. 2020-0208747 in its entirety.

FIGS. 1-3 depict one embodiment of fluid transfer system 15. Fluid transfer system 15 includes at least one valve tree 20. While FIGS. 1 and 2 depict three valve trees 20, any number of valve trees 20 may be included in fluid transfer system 15. Fluid transfer system 15 may further include header 100, such as when fluid transfer system 15 includes two or more valve trees 20. In certain embodiments, header 100 may supply fluid to valve tree 20, such as, for example and without limitation, pressurized frac fluid. Fluid transfer system 15 also includes coupler 207 fluidly coupling header 100 to valve tree 20. Although in the embodiment shown in FIGS. 1 and 2, each valve tree 20 includes only one coupler 207 fluidly communicating with header 100, multiple couplers 207 may be used to fluidly communicate between a single valve tree 20 and header 100. Each coupler 207 preferably includes a coupler flow path that is inclined from the horizontal, as discussed in more detail below.

As further depicted in FIGS. 1 and 2, each valve tree 20 is associated with a wellhead 16, wherein each wellhead 16 is connected to a hydrocarbon well. Pads 17 adjacent each wellhead 16 may be well cellar openings surrounding each wellhead 16 that provide access to the well and the portion of the wellhead 16 disposed below the earth's surface. Each valve tree 20 has a substantially vertical wellhead axis 217 and includes master valve 25. Valve tree 20 may optionally include a second master valve 26. Opening master valve 25 and/or second master valve 26 allows fluid flow into or out of the well through valve tree 20 and wellhead 16.

Header 100 may be connected to a fluid source for the provision of fluid such as a pressurized frac fluid to header 100. Inlet 101 may include one or more fittings 102, to which hoses or piping may be connected. Header 100 may also include at least one header multi-path flow connector 103 to which inlet 101 connects.

Header 100 may further include conduit 104 for connecting multi-path flow connector 103 to a second multi-path flow connector 103. In the present illustrative embodiment of fluid transfer system 15, three multi-path flow connectors 103 and two lengths of conduit 104 are shown. As is appreciated by those of ordinary skill in the art, any number of conduits 104 and header multi-path flow connectors 103 may be similarly connected. Although inlet 101 is shown at an end of header 100, if desired inlet 101 may be disposed at a location intermediate, or between, the ends of header 100. Header 100 may include optional isolation valve 109 positioned between header multi-path flow connector 103 and conduit 104 or between sections of conduit 104 so as to isolate flow from adjacent header multi-path flow connectors 103.

Conduit 104 may be formed of one or multiple spools 120. Spools 120 may be connected to isolation valves 109 and to header multi-path flow connector 103 by spool connections, which may be flanged connections, studded connections, threaded connections or quick connect connectors. If desired, one or more expansion spools 122, may form part of conduit 104. Each expansion spool 122 can be adjustably extended in a longitudinal direction. By adjusting the length of expansion spool 122, coupler 207 may be aligned with a respective valve tree 20.

Header multi-path flow connectors 103 may, in certain non-limiting examples, comprise studded or flanged flow tees. For example, a header multi-path flow connector 103 may comprise a studded three-way or four-way flow tee that permits flow through header multi-path flow connectors 103 both along the longitudinal axis 136 of header 100 and also out of conduit 104 into coupler 207. If a four-way flow tee is used, flow may pass into a studded flow tee, or three-way block, which may in turn be used as auxiliary, or supplemental, inlets to, or outlets from, header 100.

In circumstances where only one valve tree 20 is present, header 100 may be omitted. As with embodiments where a plurality of valve trees 20 are present, the one valve tree embodiment includes multi-path flow connector 103 that provides a flow path from inlet 101 to coupler 207.

Header 100 may be supported by at least one elevating skid 115. Elevating skid 115 may allow vertical adjustment of header 100, thereby adjusting the vertical elevation of one end of coupler 207. In certain non-limiting embodiments, each elevating skid 115 may rest on the earth's surface, on a pad, or on metal skids. The support for each elevating skid 115 may include height adjusting leveling supports. While shown in FIGS. 1 and 2 as positioned beneath header multi-path flow connectors 103 elevating skids 115 may be positioned as desired along header 100.

As described above, each valve tree 20 may be connected to a respective coupler 207 for fluid communication with header 100 and inlet 101. In certain embodiments, coupler 207 has a fixed length, meaning that there are no expansion joints or other mechanisms designed to adjust the length or height of coupler 207. In other embodiments, coupler 207 may include an expansion joint or other mechanism configured to adjust the length of coupler 207. Each coupler 207 has a longitudinal coupler axis 224.

Coupler 207 may include a header coupler connector 205, a coupler conduit 200, and a valve tree coupler connector 210. Coupler 207 may be fluidly coupled to header 100 by header coupler connector 205 and joined to valve tree 20 by valve tree coupler connector 210. Coupler conduit 200 defines longitudinal coupler axis 224. Coupler 207 may be configured such that no two consecutive flow directions within coupler 207 are perpendicular to one another. In some embodiments, header coupler connector 205 valve tree coupler connector 210 each cause a change of 45° in the direction of fluid flow.

Coupler 207 may be connected to header 100 such that coupler axis 224 intersects header axis 136 or passes above header axis 136. In other embodiments, coupler conduit 200 may be connected to header 100 such that coupler axis 224 passes between header axis 136 and the surface of the earth. Header coupler connector 205 and valve tree coupler connector 210 may each be an angled coupler that provides a change in the direction of fluid flow.

In certain embodiments, coupler 207 may be joined directly to header 100. In embodiments in which header coupler connector 205, a coupler conduit 200, and a valve tree coupler connector 210 connects to valve tree 20 at a higher elevation, coupler conduit 200 may be inclined such that coupler axis 224 defines an angle α with respect to horizontal (FIG. 3). In some embodiments, α may be between 0° and 90°, or between 10° and 80°. In some embodiments, α may be 45°. While header coupler connector 205 and valve tree coupler connector 210 are illustrated as each producing a direction change of about 45°, alternative angles are possible.

In some embodiments, coupler axis 224 may not be perpendicular to header axis 136. By way of example, space constraints may make it advantageous to fit the various components of fluid transfer system 15 closely together, thereby constraining the positioning of the various components of system 15.

Header coupler connector 205 and valve tree coupler connector 210 may each be connected to the adjacent equipment by means of bolted flanges or the like. In some embodiments, at least one of header coupler connector 205 and valve tree coupler connector 210 may be configured to allow at least some relative rotation. By way of example, header coupler connector 205 may be configured to allow rotation of coupler conduit 200 relative to header 100.

In addition to providing a quick and efficient connecting of each coupler to its respective frac tree, coupler connectors 205, 210 may facilitate the efficient and safe installation and removal of coupler 207. Additionally, use of coupler 207 permits a user of fluid transfer system 15 to quickly disassemble, or “rig down”, the fluid transfer system 15 to access master valves 25, 26 for replacement of one or more master valves 25, 26.

In certain embodiments, coupler conduit 200 may include at least two wing valves 215. In some embodiments, four wing valves 215 may be used, for instance, where two of wing valves 215 are disposed approximately 180 degrees apart from the other two wing valves 215 and may form a row, the row having a wing valve axis 216.

Referring particularly to FIG. 1, coupler 207 may include at least one flow control valve 220. Flow control valve 220 may have a flow axis 223 that is perpendicular to axis 216 defined by wing valves 215 and is substantially parallel to the surface of the earth. Flow axis 223 may also be perpendicular to the vertical axis of valve tree 20. Flow control valve 220 may be used to control the flow of fluid from header 100 to each valve tree 20. Flow control valve 220 may have internal bore dimensions that are greater than or equal to the internal bore dimension of, master valves 25, 26. In some embodiments, flow control valve 220 may be directly coupled to a valve tree multi-path flow connector 260. In certain embodiments, for example if fluid transfer system 15 is used with a single frac tree, coupler 207 may not include flow control valve 220.

Each coupler 207 may include or be in fluid communication with a swab valve 230 on its respective valve tree 20. In other embodiments, swab valve 230 is connected to coupler 207 by a flanged connection, studded connection, threaded connection, clamp, or quick connect connector.

Valve tree multi-path flow connector 260 may be any suitable device, including but not limited to: a multi-path flow connector with three fluid connection ports, a studded 5-way flow cross or a 6-way flow cross with a blind flange may be positioned below swab valve 230. Valve tree multi-path flow connector 260 may be in fluid communication with: swab valve 230; wing valves 215; flow control valve 220; and valve tree 20. In certain embodiments, flow control valve 220 is directly connected to valve tree multi-path flow connector 260 without any intervening piping or components.

During the drilling of a well, wellhead 16 may be installed on each well. Valve tree 20 may be connected to wellhead 16. Master valves 25, 26 are installed, or attached, to wellhead 16. When it is desired to provide fracing fluid to two or more wells, header 100 may be positioned in a spaced relationship from the wellheads 16 and couplers 207 may be used to provide fluid communication between the header and each frac tree.

As indicated above, coupler 207 may be configured such that no two consecutive flow directions within coupler 207 are perpendicular to one another. Each change of direction reduces the fluid pressure and increases wear on equipment. By reducing the number of 90° changes in fluid flow direction, the present system reduces the amount by which the fluid must change direction as it passes from header 100 to wellhead 16, thereby also reducing the fluid pressure loss and wear on equipment.

Coupler 207 may be assembled at the well site; in other embodiments, the components of the coupler 207 are preassembled at another location. Coupler 207 may be transported to the well site and be lifted, such as by a crane or other suitable lifting device and positioned above header 100 and valve tree 20. Coupler 207 may be lowered and connected to header 100 and valve tree 20, using header coupler connector 205 and valve tree coupler connector 210. When header coupler connector 205 and valve tree coupler connector 210 are flanged or studded connectors, header coupler connector 205 and valve tree coupler connector 210 may be affixed with bolts. Alternatively, quick connect connectors may be used for header coupler connector 205 and valve tree coupler connector 210.

If fluid transfer system 15 includes a plurality of valve trees 20, additional portions of header 100 may be assembled, as shown in FIGS. 1 and 2. These additional portions of header 100 are assembled in the manner previously described and are mounted on elevating skids 115 and are each disposed in a spaced relationship from wellheads of each additional valve tree 20. As previously described, these additional sections are fluidly connected, so that header 100 appears as shown in FIGS. 1 and 2. Each additional coupler 207 may be connected between header 100 and a valve trees 20 as shown in FIGS. 1 and 2. Fluid transfer system 15 may be enlarged for use with additional valve trees, as by attaching additional portions of the header 100 and couplers.

While several exemplary embodiments have been provided in the present disclosure, it may be understood that the disclosed embodiments might be embodied in many other specific forms without departing from the spirit or scope of the present disclosure and the appended claims. The present examples are to be considered as illustrative and not restrictive, and the intention is not to be limited to the details given herein. For example, the various elements or components may be combined or integrated in another system or certain features may be omitted, or not implemented.

In addition, the various exemplary embodiments described and illustrated in the various embodiments as discrete or separate may be combined or integrated with other systems, modules, techniques, or methods without departing from the scope of the present disclosure. Other examples of changes, substitutions, and alterations are ascertainable by one skilled in the art and may be made without departing from the spirit and scope disclosed herein.

Claims

1. A fluid transfer system for use with a valve tree at a well, the valve tree having a wellhead axis, the system comprising:

a header having a header flow axis; and

a coupler connected to the valve tree and the header and providing fluid communication between the valve tree and the header, the coupler having a coupler flow axis;

wherein the coupler is configured such that no two consecutive flow directions within the coupler are perpendicular to one another.

2. The system of claim 1 wherein the coupler includes a coupler inlet and wherein the coupler inlet is at substantially the same elevation as the header flow axis

3. The system of claim 1 wherein the coupler includes a coupler inlet and wherein the coupler flow axis passes above the header flow axis.

4. The system of claim 1 wherein the coupler is connected to the header such that the coupler flow axis passes between the header axis and the surface of the earth.

5. The system of claim 1 wherein the coupler includes a coupler conduit defining the coupler flow axis and wherein the coupler flow axis intersects the header flow axis.

6. The system of claim 1 wherein the system includes a multi-path flow connector in fluid communication with the valve tree and a flow control valve having a flow axis, the flow control valve directly coupled to the multi-path flow connector and in fluid communication with the header, and wherein the connection between the coupler and the valve tree includes the multi-path flow connector.

7. The system of claim 6 wherein the header includes a conduit connected to an inlet through a header multi-path flow connector and an isolation valve.

8. The system of claim 7, wherein the conduit includes an expansion spool.

9. The system of claim 6 wherein the valve tree includes a master valve, wherein the valve tree multi-path flow connector is disposed vertically above the master valve, and wherein the flow axis of the flow control valve is substantially perpendicular to the flow axis of the master valve.

10. The system of claim 6, wherein the multi-path flow connector comprises a studded or flanged flow tee.

11. The system of claim 1, wherein the coupler has a fixed length.

12. The system of claim 1, wherein the coupler includes an expansion joint.

13. The system of claim 1, wherein the coupler is connected to the header by a header coupler connection and to the valve tree by a valve tree coupler connector.

14. The system of claim 13, wherein the header coupler connector and the valve tree coupler connector are each adapted to cause a change of 45° in the direction of fluid flow.

15. The system of claim 1 wherein the header further comprises an expansion spool.

16. The system of claim 1, further comprising an elevating skid, the elevating skid positioned beneath the header.

17. The system of claim 1, further comprising an isolation valve, wherein the isolation valve is positioned so as to isolate a section of the header.