In the drilling and completion industry, the formation of boreholes for the purpose of production or injection of fluid is common. The boreholes are used for exploration or extraction of natural resources such as hydrocarbons, oil, gas, water, and alternatively for CO2 sequestration.
To increase the production from a borehole, the production zone can be fractured to allow the formation fluids to flow more freely from the formation to the borehole. The fracturing operation includes pumping fracturing fluids including proppants at high pressure towards the formation to form and retain formation fractures. A conventional fracturing system passes pressurized fracturing fluid through a tubular string that extends downhole through the borehole that traverses the zones to be fractured. The string may include valves that are opened to allow for the fracturing fluid to be directed towards a targeted zone. To remotely open the valve from the surface, a ball is dropped into the string and lands on a ball seat associated with a particular valve to block fluid flow through the string downhole of the ball and consequently build up pressure uphole of the ball which forces a sleeve to move in a downhole direction thus opening a frac port in the wall of the string. When multiple zones are involved, the ball seats are of varying sizes with a downhole-most seat being the smallest and an uphole-most seat being the largest, such that balls of increasing diameter are sequentially dropped into the string to sequentially open the valves from the downhole end to an uphole end. Thus, the zones of the borehole are fractured in a “bottom-up” approach by starting with fracturing a downhole-most zone and working upwards towards an uphole-most zone.
Because hydrocarbon production wells are often drilled into unconsolidated formations, sand and fines from those formations will tend to enter the production tubing along with the produced fluids. To prevent this, a fracturing and gravel packing treatment can be performed, commonly referred to as a “frac pack,” within the wellbore prior to production.
A conventional frac pack system includes a screen assembly that is placed in the wellbore near the unconsolidated formation. The screen assembly radially surrounds a wash pipe, and both the screen assembly and wash pipe are connected, at their upper ends, to a service tool. The usual service tool includes a production packer and a cross-over tool, which are connected to a work string that extends downwardly from the surface. The work string is used to position the screen assembly in the wellbore. Packers provide fluid sealing. The frac pack system can be placed into a “squeeze” configuration, wherein no fluids return to the surface. In this configuration, fracturing fluid is passed through the cross-over tool, into the annulus and then into the formation. Alternately, the frac pack system can be placed into a “circulation” position to allow flow through the wash pipe back to the surface. Gravel packing slurry is then flowed in through the cross-over tool to gravel pack the annulus around the screen assembly. The gravel collects around the screen to form the gravel pack. The gravel allows flow of produced fluids there through and into the screen while blocking the flow of particulates produced with the formation fluids. When gravel packing is completed, the service tool is detached from the screen assembly and withdrawn from the wellbore, leaving the gravel packed screen assembly and packer in place.
The art would be receptive to improvements in frac and gravel packing systems and methods.
A frac and gravel packing system including a tubular having a longitudinal axis, a wall defining an interior flowbore, a radial frac port and a radial production port extending through the wall in a first zone of an annular region surrounding the tubular; a screen surrounding the production port, the frac port not covered by the screen; a sleeve system including a sleeve longitudinally shiftable with respect to the longitudinal axis of the tubular, the sleeve configured to cover the frac port in a first position of the sleeve and uncover the frac port in a second position of the sleeve; and, a return path arranged to permit return fluid from a fracturing operation to exit the first zone of the annular region, wherein the return fluid passes through the screen prior to accessing the return path.
A method of fracturing a formation and gravel packing a screen, the method including: actuating a sleeve to reveal a radial frac port in a tubular; revealing a radial production port in the tubular; fracturing a formation in a first zone through the frac port with fracturing fluid; packing a screen surrounding the production port with particulates from the fracturing fluid and the formation; passing return fluids from the fracturing fluid through the screen; and, sending the return fluids through a return path to a location uphole or downhole of the first zone.
The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:
A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.
With reference to
When the system 10 is positioned and secured within the borehole 30, and the formation 32 within the zone 28 is ready to be fractured, the first sleeve 46 is moved longitudinally within the tubular 14 to reveal the frac port 24, as shown in
The first sleeve 46 further includes return path aperture 64 that forms part of a return path 66 of the system 10. The return path 66 also includes a longitudinal pathway 68, and the return path aperture 64 is alignable with a radial access 70 to connect with the longitudinal pathway 68. An O-ring seal 72 may be positioned on each side of the radial access 70. Thus, the longitudinal pathway 68 is made accessible to the flowbore 20 at substantially the same time the frac port 24 is opened. In an embodiment where the first sleeve 46 includes a production aperture in addition to the return path aperture 64, then the frac port 24, the radial access 70, and the production port 26 can all be exposed at substantially the same time during the one operation of moving the first sleeve 46 from the closed position to the open position.
When frac pressure is used to move the first sleeve 46 to the open position shown in
The system 10 includes one embodiment of directing the return fluid 78 to surface in uphole direction 59. The return path 66 may, in one embodiment, pass through the packers, extensions, and concentric screens of the system 10. Since the flowbore 20 is blocked by the plug 54, the return fluid 78 will naturally exit into the longitudinal pathway 68 of the return path 66 via the aligned radial access 70 and return path aperture 64. The longitudinal pathway 68 may be formed through the wall 22 of the tubular 14, and past the second sleeve 52. The pathway 68 may, in one embodiment, be formed by gun drills. In one embodiment, the second sleeve 52 includes a connecting portion 84 of the return path 66, such as an indent, that fluidically connects a downhole portion 86 of the pathway 68 with an uphole portion 88 of the pathway 68 when the second sleeve 52 is in the un-shifted condition shown in
After the completion of the fracturing and gravel packing operations, upon the creation of fractures 76 and a gravel pack 82, and after the return fluid 78 has passed through the return path 66, the frac port 24 can be closed by longitudinally shifting the second sleeve 52 to the closed position, as shown in
Thus,
Turning now to
With respect to
In the embodiment of
In embodiments of the system 400, the tubular 415 (with frac sleeve) and screen 434 would have flow areas to allow for returns. The tool 404 could include a valve to provide the ability to switch from squeeze and circulate during treating. The tool 404 may further have the ability to provide set-down and upstrain indication. Upon reaching the appropriate frac port 424, the tool 404 could be sat down, opening the frac sleeve and, in alternative embodiments, additionally closing a flapper or “turning on” a ball seat at the downhole end 408. However, before turning on such a ball seat to be used during the fracturing operation, a plug such as a ball or dart could be pumped down to open a monitoring or sliding sleeve valve. This would allow fluid and proppant to reach the bottom of the zone during the fracturing operation. The ball seat could be a collet or dog style. Once the seat has been “turned on”, a plug such as a ball/dart could be pumped down and land on the seat, or alternative devices for enabling a blocked downhole end 408 may be utilized. Fracking operations can then be performed, and once complete, the frac sleeve could be closed and the ball seat “turned off” At this point depending on what the ball is made of and how it holds up, the ball may be retrieved and taken to the next zone to repeat the process. For example, once the ball seat has been turned off and sliding sleeve closed, the ball used during fracturing could by pumped down to close an additional sleeve. This sleeve could have been opened (by ball or mechanically) before the fracturing operation to allow fluid and proppant to reach the bottom of the zone before returning to surface. Thus, in one embodiment, the system 400 enables a method where the tool 404 can shift a frac sleeve open, allowing a ball seat to “activate” to accept a ball, while simultaneously exposing the access 469 allowing for returns. A ball can then be dropped and the well fracked. Once fracking is complete, the tool 404 can shift the frac sleeve closed and allow the ball seat to deactivate. The tool 404 can then be picked up to a position to be reversed out and then moved to the next zone to have the process repeat. It should be understood that the system 400 does not necessarily need to use a ball for the system 400 to function, as alternative devices to close the downhole end 408 may be utilized. Tool 404, tubular 415, and tubular 414 each include ports 411, 417, 424 that are alignable, so that as slurry/or frac fluid 74 is pumped through frac port 424, fluid 78 from the slurry 74 enters screen 434 and makes its way to longitudinal pathway 468. The longitudinal pathway 468 could deliver returns through a packer and/or other features of a completion using the system 400. Alternatively, there could be an annular passage between the tubular watt 410 of tool 404 and tubular 415 that could take return fluids 78 back to surface. After a treatment is complete, the tool 404 can be retrieved, closing the tubular 415 by either axial or rotational motion.
The embodiments of a system described herein provides return paths 66, 166, 266, 366, 466 that provide the ability to complete a frac and gravel pack in a time efficient manner. While particular embodiments for the return paths have been shown, portions of the return paths may alternatively be provided by shunt tubes. While the sleeve system 44 has been disclosed as ball-activated, using the plugs, other types of sleeve activation may be incorporated, such as, but not limited to electronically triggered systems, however some embodiments of the systems described herein enable the completion of a frac and gravel pack using a ball drop system, which is an unconventional procedure and provides advantages of time savings and expense. In some of the embodiments of the systems described herein, the features of the systems for fracking, gravel packing, and production, (aside from the plugs) remain within the borehole 30 for operation, thus negating the need for insertion and removal of service tools. Additional mechanical intervention is not required for accessing the return path in each embodiment. There is no need to manipulate a work string using a tool to provide access to a return path, eliminating the need for a service tool assembly to interact with the sleeve, thus removing that interface. In some of the embodiments of the system, the system may be advantageously run in one trip and left in the well for the fracturing operation, the gravel packing operation, and for production. This could lead to substantially less complex multi-zone wells, not just in terms of the completion itself but also running and operating the system. Further, the return paths of the embodiments of the systems 10, 100, 200, 300, 400 may be provided to direct return fluids 78 to surface, in a downhole direction 58 to another zone through the flowbore 20 or to a dead zone 302, and thus the system is configurable depending on the needs of the customer and for the operation.
Set forth below are some embodiments of the foregoing disclosure:
A frac and gravel packing system includes: a tubular having a longitudinal axis, a wall defining an interior flowbore, a radial frac port and a radial production port extending through the wall in a first zone of an annular region surrounding the tubular; a screen surrounding the production port, the frac port not covered by the screen; a sleeve system including a sleeve longitudinally shiftable with respect to the longitudinal axis of the tubular, the sleeve configured to cover the frac port in a first position of the sleeve and uncover the frac port in a second position of the sleeve; and, a return path arranged to permit return fluid from a fracturing operation to exit the first zone of the annular region, wherein the return fluid passes through the screen prior to accessing the return path.
The frac and gravel packing system of any of the preceding embodiments, wherein the return path is configured to direct return fluid in an uphole direction.
The frac and gravel packing system of any of the preceding embodiments, wherein the return path is formed at least partially by a longitudinal pathway through the wall of the tubular.
The frac and gravel packing system of any of the preceding embodiments, wherein the sleeve is a first sleeve, and the sleeve system further includes a second sleeve, the return path formed at least partially by the second sleeve, and longitudinal movement of the second sleeve to re-cover the frac port interrupts the return path in the first zone.
The frac and gravel packing system of any of the preceding embodiments, wherein the sleeve includes an aperture, and the return path includes a radial access to the longitudinal pathway, and the sleeve blocks the radial access in the first position of the sleeve and unblocks the radial access in the second position of the sleeve.
The frac and gravel packing system of any of the preceding embodiments, wherein the return path is configured to direct return fluid in a downhole direction.
The frac and gravel packing system of any of the preceding embodiments, wherein the return fluid is directed through the production port and into the flowbore.
The frac and gravel packing system of any of the preceding embodiments, wherein the return fluid is directed through a space between the screen and the tubular to a location outside of the first zone.
The frac and gravel packing system of any of the preceding embodiments, wherein the sleeve is a first sleeve and additionally covers the production port in the first position of the first sleeve and uncovers the production port in the second position of the first sleeve, the sleeve system further including a second sleeve, and longitudinal movement of the second sleeve re-covers the frac port in a third condition.
The frac and gravel packing system of any of the preceding embodiments, wherein the first sleeve includes an aperture, and alignment of the aperture and the production port in the second position of the first sleeve exposes the production port.
The frac and gravel packing system of any of the preceding embodiments, wherein the sleeve is a first sleeve and is positioned within the tubular, and the sleeve system further includes a second sleeve that blocks the production port in a first position of the second sleeve and exposes the production port in the second position of the second sleeve, the second sleeve disposed interiorly of the tubular.
The frac and gravel packing system of any of the preceding embodiments, wherein the second sleeve further including a piston area configured to receive frac pressure from the frac port to hydraulically move the second sleeve to the second position.
The frac and gravel packing system of any of the preceding embodiments, further comprising a third sleeve, and longitudinal movement of the third sleeve is configured to re-cover the frac port.
The frac and gravel packing system of any of the preceding embodiments, further comprising a tubular tool located concentrically within the tubular, the tool configured to shift the sleeve, the return path disposed radially exterior of the tool.
A method of fracturing a formation and gravel packing a screen, the method including: actuating a sleeve to reveal a radial frac port in a tubular; revealing a radial production port in the tubular; fracturing a formation in a first zone through the frac port with fracturing fluid; packing a screen surrounding the production port with particulates from the fracturing fluid and the formation; passing return fluids from the fracturing fluid through the screen; and, sending the return fluids through a return path to a location uphole or downhole of the first zone.
The method of any of the preceding embodiments, wherein, in a first position, the sleeve blocks the frac port and the production port, and, in a second position of the sleeve, the sleeve substantially simultaneously uncovers the frac port and the production port.
The method of any of the preceding embodiments, wherein sending the return fluids through the return path includes passing the return fluids in an uphole direction through a longitudinal pathway at least partially formed in a wall of the tubular.
The method of any of the preceding embodiments, wherein the sleeve is a first sleeve, and further comprising substantially simultaneously re-covering the frac port and interrupting the return path with a second sleeve.
The method of any of the preceding embodiments, wherein sending the return fluids through the return path includes passing the return fluids in a downhole direction through the flowbore.
The method of any of the preceding embodiments, wherein sending the return fluids through the return path includes directing return fluids in a downhole direction through a space between the screen and the tubular to a location outside of the first zone.
The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Further, it should further be noted that the terms “first,” “second,” and the like herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The modifier “about” used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the particular quantity).
The teachings of the present disclosure may be used in a variety of well operations. These operations may involve using one or more treatment agents to treat a formation, the fluids resident in a formation, a wellbore, and/or equipment in the wellbore, such as production tubing. The treatment agents may be in the form of liquids, gases, solids, semi-solids, and mixtures thereof. Illustrative treatment agents include, but are not limited to, fracturing fluids, acids, steam, water, brine, anti-corrosion agents, cement, permeability modifiers, drilling muds, emulsifiers, demulsifiers, tracers, flow improvers etc. Illustrative well operations include, but are not limited to, hydraulic fracturing, stimulation, tracer injection, cleaning, acidizing, steam injection, water flooding, cementing, etc.
While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited.
This application claims the benefit of an earlier filing date from U.S. Provisional Application Ser. No. 62/402,697 filed Sep. 30, 2016, the entire disclosure of which is incorporated herein by reference.
Number | Date | Country | |
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62402697 | Sep 2016 | US |