RU2601641C2 - Multi-zone completion with formation hydraulic fracturing - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: group of inventions relates to downhole tool for use in oil and gas wells and, particularly, to completion with openings equipment, which can be used for formation hydraulic fracturing in multi-zone wells. Well shaft completion equipment includes casing string assembly with plurality of casing string links and at least one adapter coupling for connection of casing string links. At least one adapter coupling comprises tubular housing having internal flow path and at least one hydraulic fracturing opening made with possibility to create hydraulic connection between adapter coupling outer surface and inner flow path. Equipment includes piece of flexible tubing string. It is installed in casing string assembly. Flexible tubing string includes internal flow path. Between flexible tubing string and casing string assembly annular space is formed. Drill string bottom assembly is connected to flexible tubing string. Drill string bottom assembly comprises formation hydraulic fracturing opening. It is made with possibility of hydraulic connection creation between flexible tubing string internal flow path and annular space. Equipment includes packer. It is installed in specified place to enable contact with at least one adapter coupling during packer operation. At that, packer is made with possibility of annular space above packer isolation from annular space under packer, so that fluid medium passing downwards along flexible tubing string, can flow out of formation hydraulic fracturing opening, thus creating pressure drop at packer to open hydraulic fracturing opening.

EFFECT: higher reliability of formation hydraulic fracturing in multi-zone wells.

21 cl, 21 dwg

Description

 [01] The present invention is a partial continuation of the application U.S. Patent Application No. 12/971932 entitled ″ MULTI-ZONE FRACTURING COMPLETION ″, John Edward Ravensbergen, registered December 17, 2010, is a partial continuation of the application U.S. Patent Application No. 12/842099 titled ″ BOTTOM HOLE ASSEMBLY WITH PORTED COMPLETION AND METHOD OF FRACTURING THEREWITH ″, John Edward Ravensbergen and Lyle Laun was registered on July 23, 2010, which claims priority for U.S. provisional application. Provisional Patent Application No. 61/228793 titled ″ BOTTOM HOLE ASSEMBLY WITH PORTED COMPLETION AND METHOD OF FRACTURING THEREWITH ″, John Edward Ravensbergen, registered July 27, 2009, each of which is incorporated herein by reference in its entirety.

FIELD OF TECHNOLOGY

[02] The present invention relates generally to a downhole tool for use in oil and gas wells, and more particularly, to window completion equipment that can be used for hydraulic fracturing in multi-zone wells.

BACKGROUND

[03] Completion of oil and gas wells is usually performed after drilling oil and gas wells. Part of the completion method involves lowering the layout of the well casing into the well. The casing arrangement may include several sections of casing that are held together by adapter sleeves. A standard adapter sleeve may be, for example, a relatively short tubular or annular structure with an internal thread at the ends for fastening with an external thread at the ends of the casing sections. The layout of the downhole casing can be installed in the wellbore using various techniques. One such technique involves filling the annulus between the wellbore and the outer diameter of the casing with cement.

[04] After installing the casing in the wellbore, perforation and fracturing can be performed. Generally, perforation involves making holes through a wellbore casing into a formation using well-known devices, such as a perforating gun or an abrasive perforator. The perforated zone can then be hydraulically isolated and hydraulic fractured to increase the size of the source holes in the formation. The proppant is introduced into the enlarged holes to prevent closing of the holes.

[05] More recently, techniques have been developed by which perforation and hydraulic fracturing are performed using a flexible tubing string. One such technique is known as a hydraulic fracturing method through the annular space of a flexible tubing, or abbreviated hydraulic fracturing using coiled tubing, is disclosed in U.S. Patents. Patent No. 6474419, 6394184, 6957701 and 6520255, each of which is fully incorporated by reference into this document. For practical application of the techniques described in the above patents, the work string, which includes the layout of the bottom of the drill string (BHA), generally remains in the wellbore during hydraulic fracturing (hydraulic fracturing) of the formation.

[06] One punching method, known as abrasive punching with a cumulative punch, involves using a sand slurry to cut holes through the casing, cement, and into the wellbore. Then hydraulic fracturing can be carried out through the holes. One of the problems associated with abrasive perforation is that the sand used in perforation can remain in the annular space of the wellbore and can potentially interfere with the hydraulic fracturing process. Therefore, in some cases, sand cleaning of the wellbore may be required, which can be a lengthy process that takes one or several hours in each production zone in the well. Another problem associated with abrasive perforation is that fluid consumption increases for cutting perforations and either circulating excess solids to remove abrasive perforating fluid and sand from the well or before fracturing and during fracturing. In industry, there is a growing need to create more zones in multi-zone wells, and some horizontal wells may have 40 zones or more. Cleaning sand of such a large number of zones can significantly increase operating time, require the use of excessive volumes of fluids, and increase the cost. Using excessive volumes of fluids can also create environmental problems. For example, the method requires more road transport, an increase in the fleet of tanks and heating costs, and in addition, similar requirements arise when extracting fluid from a well.

[07] Techniques for completing a well without perforation are known in the art. One such technique is known by the name of the company as ending in the Packers-plus style. Instead of completion cementing, this technique involves lowering the packers for the uncased zone of the wellbore into the well to install the casing assembly. The casing arrangement includes adapter couplings with windows and sliding couplings. After installing the casing in the well, the windows can open due to the operation of the sliding sleeves. Then through the windows you can perform hydraulic fracturing.

[08] For multi-zone wells, several adapter couplings with windows are used in combination with sliding coupling arrangements. Sliding sleeves are mounted on the inner diameter of the casing and / or adapter sleeves and can be held in place by shear pins. In some designs, the lowest sliding sleeve is capable of being hydraulically opened using a differential pressure across the sleeve assembly. After installing the casing with adapter couplings with windows, hydraulic fracturing is performed in the deepest zone of the well. This process may include hydraulic displacement of the sliding sleeves in the first zone to open the windows and then pumping the fracturing fluid into the formation through the open windows of the first zone. After hydraulic fracturing of the first zone, a ball is dropped into the well. The ball beats the next sliding sleeve located on top of the first fractured zone in the well and at the same time opens the windows for hydraulic fracturing of the second zone. After hydraulic fracturing of the second zone, the second ball, which is slightly larger than the first ball, is reset to open the windows for hydraulic fracturing of the third zone. This process is repeated using increments of the diameter of the balls to open the windows in each zone successively closer to the wellhead until hydraulic fracturing is performed in all zones. However, since the diameter of the well is limited, and the diameters of the balls generally increase in increments of a quarter of an inch (6 mm), this method is limited to hydraulic fracturing in only 11 or 12 zones in the well with acceptable diameters of the balls. In addition, the use of coupler and packer arrangements for installing a downhole casing in this method can be costly. In addition, the arrangement of sliding sleeves and balls can significantly reduce the inner diameter of the casing, which is often unacceptable. After completion of hydraulic fracturing, to stimulate the inflow, it is often necessary to cut balls and ball nests from the casing.

[09] Another method used in open hole wells in the production area (which use packers to secure the casing in the well) is similar to the Packers-plus completion described above, except that instead of dropping balls to open windows sliding clutch subassemblies are made with the possibility of mechanical opening. For example, a switching tool can be used to open and close sliding sleeves for hydraulic fracturing and / or other desired purposes. As in the Packers-plus-style completion option, sliding sleeve arrangements and packers for installing the well casing in this method can be expensive. Additionally, sliding sleeve arrangements may undesirably reduce the inner diameter of the casing. In addition, sliding sleeves are susceptible to failure due to erosion from the high speed of the sand slurry and / or sand, which interfere with the mechanisms.

[10] Another technique for hydraulic fracturing without perforation is disclosed in the U.S. simultaneous review application. Patent Application No. 12/826372 entitled ″ JOINT OR COUPLING DEVICE INCORPORATING MECHANICALLY-INDUCED WEAK POINT AND METHOD OF USE, ″ registered June 29, 2010, Lyle E. Laun, is incorporated by reference in its entirety.

[11] The present invention is directed to overcoming or at least mitigating the effects of one or more of the problems set forth above.

SUMMARY OF THE INVENTION

[12] The following is an summary of the invention to provide an understanding of some of the aspects disclosed herein. This entity is not an exhaustive review, and is not intended to identify key or critical elements or determine the scope of the invention set forth in the attached claims.

[13] One embodiment of the present invention is a borehole completion system that includes a housing operably coupled to a casing. The casing includes at least one window passing through the casing and a sliding sleeve connected to the casing, which can be moved between the open position and the closed position. In the closed position, the slip clutch prevents hydraulic communication through the casing windows. The system includes a layout of the bottom of the drill string, which has a packing element and a latch. The latch is made with the possibility of selectively connecting the layout of the bottom of the drill string with a sliding sleeve. The packing member is configured to seal between the bottom of the drill string and the sliding sleeve.

[14] The wellbore completion system may also include a shearing device configured to selectively hold the sliding sleeve in the initial closed position and to release the sliding sleeve as a result of applying a predetermined force. The system may include an expandable device configured to selectively hold the sliding sleeve in the open position after being released and moved from the closed position. The expandable device may be configured to connect to a recess in the casing. The bottom hole assembly is connected to a flexible tubing, which can be used to install the bottom hole assembly adjacent to the casing provided with windows. The bottom of the drill string may include a casing collar locator. The latch and packer bottom hole assembly may be pressure actuated. The wellbore completion system may include a plurality of windowed shrouds along the casing, each including a sliding sleeve moving between a closed position and an open position.

[15] One embodiment of the present invention is a method of treating a wellbore or treatment to enhance inflow of a near-wellbore zone. The method includes mounting the bottom of the drill string in a section of the casing adjacent to the first sliding sleeve operably connected to the casing. The sliding sleeve is movable between a first position preventing hydraulic communication through a first window in a casing and a second position providing hydraulic communication through a first window in a casing. The method includes connecting the bottom of the drill string assembly to the first sliding sleeve and moving the bottom of the drill string to move the first sliding sleeve from the first or closed position to the second or open position.

[16] The method may include processing a wellbore adjacent to a first casing window. The method may further include disconnecting the bottom of the drill string assembly from the first sliding sleeve and installing the bottom of the drill string adjacent to the second sliding sleeve operably connected to the casing. The second sliding sleeve is movable between a first position preventing hydraulic communication through a second window in the casing, to a second position providing hydraulic communication through a second window. The method may include connecting the bottom of the drill string assembly to the second sliding sleeve and moving the bottom of the drill string to move the second sliding sleeve from the closed position to the open position. The method may include processing the wellbore adjacent to the second window.

[17] The connection of the bottom portion of the drill string to the sliding sleeve may include activating a latch to connect to the sliding sleeve portion. The method may include creating a seal between the layout of the bottom of the drill string and the sliding sleeve. The method may include selectively releasing the sliding sleeve from the first position before moving the bottom assembly of the drill string to move the sliding sleeve. The selectively sliding sleeve may comprise a shear device that can be sheared by increasing the pressure in the casing above the bottom of the drill string, moving the flexible tubing down the casing, or a combination of increasing pressure and moving the flexible tubing. The method may include selectively holding the sliding sleeve in an open position. Installing the bottom of the drill string assembly and connecting the bottom of the drill string to the sliding sleeve may include moving the flexible tubing only upward. The method may include pumping fluid down a flexible tubing to actuate the bottom assembly of the drill string.

[18] An embodiment of the present invention provides wellbore completion equipment. Borehole completion equipment comprises a casing arrangement comprising a plurality of casing units. At least one adapter sleeve is installed to connect the casing links. At least one adapter sleeve comprises a tubular body having an internal flow path and at least one hydraulic fracture window configured to provide hydraulic communication between the outer surface of the adapter sleeve and the internal flow path. A piece of flexible tubing can be installed in the right place in the casing layout. The flexible tubing contains an internal flow path, wherein an annular space is formed between the flexible tubing and the casing arrangement. The layout of the bottom of the drill string is connected to a flexible tubing. The layout of the bottom of the drill string contains a fracturing hole, configured to create a hydraulic communication between the internal flow path of the flexible tubing and the annular space. The packer can be installed in the right place to provide contact with at least one adapter sleeve when the packer expands. The packer is configured to isolate the annular space above the packer from the annular space below the packer, so that the fluid flowing down the flexible tubing can create a differential pressure on the packer to open the fracture window.

[19] Another embodiment of the present invention provides a method for completing a hydrocarbon production wellbore. The method comprises launching a flexible tubing into a casing arrangement of a wellbore. The casing arrangement comprises a plurality of casing units and one or more adapter couplings installed to connect the casing units together. The first adapter sleeve of one or more adapter sleeve includes a first fracturing window. Fluid is pumped through a flexible tubing to apply a differential pressure to open the first casing string fracture window. Hydraulic fracturing of the wellbore is carried out by supplying hydraulic fracturing fluid through the first hydraulic fracturing window.

BRIEF DESCRIPTION OF THE DRAWINGS

[20] In FIG. 1 shows cementing equipment for completion of a section of a wellbore according to an embodiment of the present invention.

[21] In FIG. 2 shows an enlarged adapter sleeve and bottom hole assembly used in completion of a wellbore. FIG. 1 according to an embodiment of the present invention.

[22] In FIG. 3 shows an enlargement of a locking cam used in completing the wellbore of FIG. 1, according to an embodiment of the present invention.

[23] In FIG. 4 is an isometric illustration of an adapter sleeve according to an embodiment of the present invention.

[24] In FIG. 5 shows a cross section of the adapter sleeve of FIG. 4 according to an embodiment of the present invention.

[25] In FIG. 6 shows the valve used in the adapter sleeve of FIG. 4, according to an embodiment of the present invention.

[26] In FIG. 7 illustrates an adapter sleeve used with a flexible tubing string and uncoupling tool with packers for isolating a fracturing zone in a well according to an embodiment of the present invention.

[27] In FIG. 8 shows open-hole completion equipment with open-hole packers according to an embodiment of the present invention.

[28] In FIG. 9 shows an enlarged adapter sleeve and bottom hole assembly according to an embodiment of the present invention.

[29] In FIG. 10 shows a bottom hole assembly used in completion of a borehole according to an embodiment of the present invention.

[30] In FIG. 11 shows with enlargement the upper portion of the adapter sleeve and the bottom hole assembly of the embodiment of FIG. 10.

[31] In FIG. 12 is an enlarged view of the lower portion of the adapter sleeve and the bottom hole assembly of the embodiment of FIG. 10.

[32] In FIG. 13 is an enlarged view of a mandrel section of a bottom hole assembly according to an embodiment of the present invention.

[33] In FIG. 14 shows a cross section of the end of the adapter sleeve of FIG. eleven.

[34] In FIG. 15 is a cross-sectional view of the adapter sleeve with the valve in the closed position according to an embodiment of the present invention.

[35] In FIG. 16 shows an adapter sleeve used with a flexible tubing string and a release tool with packers for isolating a fracturing zone in a well according to an embodiment of the present invention.

[36] In FIG. 17 is a cross-sectional view of a windowed wellbore completion equipment according to an embodiment of the present invention.

[37] In FIG. 18 is a cross-sectional view of a bottom assembly of a drill string secured to a portion of a windowed hole completion equipment. FIG. 17 with an adapter sleeve provided with windowed equipment for completing a wellbore in a closed position.

[38] In FIG. 19 is a cross-sectional view of a bottom assembly of a drill string secured to a portion of a windowed hole completion equipment. FIG. 17 with an adapter sleeve provided with windowed equipment for completing a wellbore in an open position.

[39] In FIG. 20 is a cross-sectional view of a borehole completion equipment according to an embodiment of the present invention.

[40] In FIG. 21 is a cross-sectional view of a borehole completion equipment that includes an abrasive hammer drill according to an embodiment of the present invention.

[41] Although the invention may have various modifications and alternative forms, specific embodiments are shown by way of example in the drawings and are described in detail later in this document. However, it should be understood that the invention is not limited to the particular forms disclosed. On the contrary, the invention covers all modifications, equivalents and alternatives corresponding to the essence and scope of the invention defined in the attached claims.

DETAILED DESCRIPTION

[42] In FIG. 1 shows a portion 100 of a well completion equipment according to an embodiment of the present invention. The wellbore completion portion 100 includes a bottom hole assembly 102 (“BHA”) within the casing 104. Any suitable BHA may be used. In an embodiment, the BHA 102 may have a design for hydraulic fracturing in a multi-zone well. An example of a suitable BHA is disclosed in a U.S. simultaneous review application. Patent Application No. 12/626006, registered November 25, 2009, in the name of John Edward Ravensbergen and under the name, COILED TUBING BOTTOM HOLE ASSEMBLY WITH PACKER AND ANCHOR ASSEMBLY, is incorporated by reference in its entirety.

[43] As more clearly shown in FIG. 2 and 3, casing 104 may include several casing units 106A, 106B and 106C that may be coupled using one or more adapter sleeves, such as adapter sleeves 108 and 110. Casing units 106A, 106B and / or 106C may be shortened pipe links, casing sections of approximately six (6) feet (1.8 m), which may be configured to facilitate proper installation of BHA in the desired area of the wellbore. The adapter sleeve 108 may be any suitable adapter sleeve. Examples of adapter sleeves for connecting casing units are well known in the art. In an embodiment, the adapter sleeve 108 may include two sections with an internal thread for connecting to the threaded insert ends of the casing string 106.

[44] In isometry, the adapter sleeve 110 is shown in FIG. 4 according to an embodiment of the present invention. The adapter sleeve 110 may include one or more fracturing windows 112 and one or more valve outlets 114. Fracturing windows 112 may intersect valve openings 118, which may be longitudinally disposed in centralizers 116. A plug 128 may be installed in valve openings 118 to prevent or reducing abnormal fluid upward passage through valve openings 118. In an embodiment, the inner diameter 113 (shown in FIG. 2) of the adapter sleeve 110 may be approximately equal to or greater than morning diameter of the casing 104. Thus, an annular space between an adapter 110 and the BHA 102 slightly throttled. In other embodiments, the inner diameter of the adapter 110 may be less than the internal diameter of the casing 104. The adapter 110 may be attached to the casing 106 by any suitable device. In an embodiment, the adapter sleeve 110 may include two sections with an internal thread for connecting to the threaded insert ends of the casing units 106B and 106C.

[45] As more clearly shown in FIG. 5, fracking windows 112 may be located passing through centralizers 116, which may provide the fracking window 112 with a relatively close proximity to the formation. In the event that the casing is cemented in the wellbore, this may increase the possibility of obtaining a through or near-through passage through the cement for hydraulic fracture windows 112.

[46] Valves 120 for controlling the flow of fluid through hydraulic fracture windows 112 are mounted in valve openings 118 of centralizers 116. When valves 120 are in the closed position, as shown in FIG. 6, the flow of fluid through fracking windows 112 is prevented or reduced.

[47] Valves 120 may include one or more seals to reduce leakage. Any suitable seal can be used. An example of a suitable seal 122 is shown in FIG. 6. Seal 122 may be configured to extend around fracture window 112 when valve 120 is installed in the desired position in the closed position. The seal 122 may include a ring 122A that fits snugly around the circumference of the valve 120 at one end, and a circular portion 122B that extends only around the portion of the valve 120 at the opposite end. This configuration can create the desired compaction effect, being easy to manufacture.

[48] The shear pin 124 can be used to hold the valve 120 closed during installation and reduces the likelihood of prematurely opening the valve 120. The shear pin 124 may be so designed that when the pin is sheared, part of the pin 124 remains in the wall of the adapter sleeve 110 and extends into the groove 126 of the valve 120. This provides the action of the cut-off part of the pin 124 as a guide, supporting the valve 120 in the desired orientation, so that the seal 122 is installed in the right place relative to the window 112 of the hydra discontinuity. The use of the sheared portion of the pin 124 as a guide is shown in FIG. 2, which shows valve 120 in the open position.

[49] The adapter sleeve 110 may be attached to the casing links in any suitable manner. In an embodiment, the adapter sleeve 110 may include two portions with an internal thread for connecting the threaded ends of the casing string 106 to the thread, as shown in FIG. 2.

[50] As also shown in FIG. 2, the packer 130 may be installed in the casing between the fracture ports 112 and the valve outlet 114. When the packer 130 is actuated, it is sealed on the inside diameter of the adapter sleeve 110 to prevent or reduce the passage of fluid further down the annular space of the wellbore. Thus, when the fluid flows downhole from the surface in the annular space between the well casing 104 and the BHA 102, a differential pressure is formed on the packer between the fracture window 112 and the valve outlet 114. The differential pressure can be used to open the valve 120.

[51] Any suitable technique can be used to position packer 130 in sleeve 110. In one example technique shown in FIG. 3, a cam 132 is used, which may be configured to enter the well 134 between the casing portions 106A and 106B. As shown in FIG. 1, the cam 132 may be part of the BHA 102. The length of the casing string portion 106B may be selected so that the adapter sleeve 110 is positioned at a desired distance from the recess 134, so that a packer 130 may be installed between the fracture window 112 and the valve outlet 114. During installation, the driller can install the BHA 102 by lowering the cam past the recess 134 and then lifting the BHA 102 until the cam 132 enters the recess 134. Additional resistance when pulling the cam 132 from the recess 134 should be detected on the surface It can provide the driller with a determination of the moment when the BHA 102 is correctly installed in the right place in the casing. This can provide the driller with location of the packer 130 relative to the standard adapter sleeve 108, which may be the next lowest adapter sleeve relative to the adapter sleeve 110.

[52] Casing 104 may be installed after drilling a well as part of completion equipment 100. In an embodiment, the casing 104 including one or more of the adapter sleeves 110 may be cemented in the wellbore. In FIG. 1 shows cement 105, which is fed into the space between the outer diameter of the casing 104 and the inner diameter of the wellbore 107. Techniques for cementing a casing string are well known in the art. In another embodiment, the casing 104 and the adapter sleeves 110 may be installed in the wellbore using packers for the uncased zone of the wellbore, where instead of cement, packers 111 are installed in the desired location between the inner diameter of the wellbore 107 and the outer diameter of the casing 104, as shown in FIG. 8. Such packers for completing the open hole zone of the wellbore are well known in the art and one skilled in the art can easily use the adapter sleeves of the present application to complete with packers for the open hole zone of the wellbore.

[53] Adapter sleeves 110 may be installed in the right place in the casing wherever hydraulic fracturing windows are required. For example, it should be noted that although a standard adapter sleeve 108 is shown as part of a casing, the adapter sleeve 108 can be replaced with a second adapter sleeve 110. In an embodiment, the sleeve 110 of the present invention can be installed in the right place in each zone of the multi-zone well.

[54] During cementing, the casing is lowered into the well and the annulus between the casing 104 and the wellbore is filled with cement. Where the valve 120 is mounted in the centralizer, a small recess 136 may be located between the outer diameter of the centralizer 116 and the outer diameter of the valve 120, as shown in FIG. 5. Recess 136 may potentially be filled with cement during cementing. Therefore, before the fluid is supplied through the valve 120, there may be a thin layer of cement in it that needs to be broken. Alternatively, the recess 136 may not be filled with cement. In an embodiment, prior to cementing, it is possible to fill the recess 136 with a grease, an obstruction to cement, or another substance to reduce the likelihood of filling the recess 136 with cement.

[55] The potential advantage of the design of the adapter sleeve of FIG. 4 is that the opening of valve 120 displaces the volume of fluid from valve hole 118 into the annular space between casing 106 and BHA 102 through valve outlet 114. Thus, the entire displaced volume resulting from opening valves 120 is located inside the completion equipment. The above ensures that the space between the wellbore and the outer diameter of the casing string 106 is filled with cement, for example, without necessarily creating a space outside the adapter sleeve for the volume of fluid that is displaced when valve 120 opens.

[56] Another possible advantage of the design of the adapter sleeve of FIG. 4 is an implementation of a substantially small pressure drop or no pressure drop between the fracture window 112 and the adapter outlet 114 of the adapter 110, prior to sealing the inside diameter of the adapter between the fracture window 112 and the valve outlet 114. This means that in multi-zone wells having several adapter couplings 110, the driller can control the opening of a specific fracturing window by installing a sealing mechanism, such as a packer 130, in the desired location without fear opening other hydraulic fracturing windows at other places in the well.

[57] The adapter sleeves of the present invention can be used in any type of well. Examples of well types in which adapter sleeves can be used include horizontal wells, vertical wells, and directional wells.

[58] Completion arrangements described above and shown in FIG. 1-3 are intended for fracturing techniques through an annular space where hydraulic fracturing fluid is injected into the annular space of the wellbore between the well casing 104 and BHA 102. However, the adapter sleeves 110 of the present invention can also be used in other fracturing techniques.

[59] One such fracturing technique is shown in FIG. 7, wherein the tubing string is used with a release tool having packers 140A, 140B for isolating a fracturing zone in a well. As shown in FIG. 7, the packer 140B may be installed in the desired location between the fracture window 112 and the valve outlet 114. This allows the opening of the valve 120 by creating a differential pressure between the fracture window 112 and the valve outlet 114 when in the area of the wellbore between the packers 140A, 140B pressure builds up. Pressure injection may be accomplished by supplying fluid down a flexible tubing with suitable pressure to open valve 120. The fluid for opening valve 120 may be fracturing fluid or other suitable fluid. After valve 120 is opened, fracturing fluid (not shown) can be pumped to the bottom of the well through a flexible tubing, into an annular space through aperture 144, and then into the formation through a fracture window 112. The potential advantage of arranging the uncoupling tool on the flexible tubing of FIG. 7 is that any proppant used during hydraulic fracturing can be isolated between packers 140A and 140B from the rest of the annular space of the wellbore.

[60] The following describes a multi-zone fracturing method using adapter sleeves 110 of the present invention. The method may include lowering the casing 104 and the adapter sleeves 110 into the wellbore after drilling. The casing 104 and adapter sleeves 110 can either be mounted in the wellbore using cementing, or using packers in a packer arrangement for an uncased portion of the wellbore, as discussed above. After installing the casing in the wellbore, BHA 102, fastened to the end of the casing string of the flexible tubing, can be lowered into the well. In an embodiment, the BHA 102 may initially descend to the bottom of the bottom or to a point near the bottom of the bottom of the well. During the descent into the well, the cams 132 (Fig. 3), due to their profile, do not fully come into contact and / or easily slip past the recesses 134. For example, the cams 132 can be configured with a small sliding angle 131 on the side facing the bottom to provide them easier sliding past the recesses 134 with a small axial force when lowering into the well.

[61] After descent to the required depth of BHA 102, the driller can begin to lift the tubing string and BHA 102 to the surface. The cams 132 may have a profile for contacting the recess 134 at a large angle 133 at the top of the cams 132, the result being an increased axial upward force when pulling the cams 132 from the recesses. This increased resistance provides the driller with detection of the desired location in the well to install the packer 130, as discussed above. Giving the cams 132 a profile providing reduced drag when lowering into the well and increased drag when climbing from the well is generally well known in the industry. After installing the packer 130 at the desired location, the packer 130 can be activated to isolate the borehole annulus between the BHA 102 and the desired adapter sleeve 110 between the fracture window 112 and the valve outlet 114.

[62] After the downhole isolation annulus at the desired transition sleeve 110 in the downhole annulus pressure may be pumped from the surface to a pressure sufficient to open the valve 120. A suitable pressure may range, e.g., from about 100 lb / ⁱⁿ² (0.7 MPa) to about 10,000 lb / ⁱⁿ² (70 MPa), from about 500 lb / ⁱⁿ² (3.5 MPa) to about 1000 lbs / ⁱⁿ² (7 MPa), 1500 lb / ⁱⁿ² (10.5 MPa) or more. The adapter sleeve 110 has such a design that all of the hydraulic fracturing windows 112 in the sleeve can open. In an embodiment, the pressure for opening the fracture windows 112 may have a setpoint less than the fracture pressure. The specified can provide a hydraulic fracturing pressure and thus for the hydraulic fracturing itself guarantee the opening of all windows 112 hydraulic fracturing. It is allowed, however, that in some situations not all hydraulic fracturing windows 112 may open. This may occur due to, for example, a malfunction or blocking of hydraulic fracturing windows with cement. After opening the hydraulic fracturing windows 112, fluids can be pumped through the hydraulic fracturing windows 112 into the wellbore. Hydraulic fracturing can be initiated and hydraulic fracturing fluids can be injected into the wellbore to perform hydraulic fracturing. Depending on the fracturing technique employed, injection may include pumping the fracturing fluid down the annular space of the wellbore, as in the embodiment of FIG. 1-3. Alternatively, fracturing fluids can be fed down the tubing string, as in the embodiment of FIG. 7. If required, a proppant, for example a sand suspension, can be used in the method. Proppant can fill the cracks and keep them open after stopping hydraulic fracturing. Hydraulic fracturing is usually stopped when the final proppant volume is reached. Buffer fluid is used to force proppant through the wellbore into the formation.

[63] A pack fluid is fluid injected before proppant is injected into the formation. The specified provides a sufficient width of the opening of cracks before reaching the proppant formation. If window couplings are used, a buffer fluid may be used as the pack fluid for further processing. As a result, fluid consumption is reduced.

[64] In multi-zone wells, the fracturing method described above may be repeated for each zone of the well. Thus, the BHA 102 can be installed in the next adapter sleeve 110, the packer can be driven, the hydraulic fracturing window 112 can be opened and the hydraulic fracturing can take place. The method may be repeated for each zone from the bottom up in the wellbore. After hydraulic fracturing, oil can exit the fracture through the hydraulic fracturing windows 112 of the adapter sleeves 110 and into the well.

[65] In an alternative multi-zone embodiment, fracturing may potentially be conducted from top to bottom or in any order. For example, a release tool such as that shown in FIG. 7 can be used to isolate the zones above and below in the well by techniques well known in the art. Fracturing windows 112 can then be opened by pressurizing through a flexible tubing similar to that described above. Hydraulic fracturing can then take place in the first zone, also in a mode similar to that described above. The release tool can then be moved to the second zone from the surface and the process can be repeated. Since the uncoupling tool can isolate the adapter sleeve from the adapter couplings higher and lower, the uncoupling tool provides hydraulic fracturing of any zone along the wellbore and eliminates the requirement to start hydraulic fracturing in the lowest zone and work upward along the casing.

[66] The design of the adapter sleeve 110 of the present invention can potentially close the valve 120 after it has been opened. This may be preferred in embodiments where some zones in a multi-zone well begin to produce water or other undesirable fluids. If the location of the water receiving zones can be detected, the couplings of such zones can be closed to prevent unnecessary flow of fluid from such zones. This can be accomplished by isolating the valve outlet 114 and then pressurizing to obtain a force closing the valve 120. For example, the uncoupling tool can be used similarly to the embodiment of FIG. 7, except that the packer 140A may be installed between the fracturing window 112 and the valve outlet 114, and the lower packer 140B may be installed on the far side of the valve outlet 114 from the packer 140A. When pressure is generated in the area between the packers, high pressure is created at the valve outlet 114, with the pressure closing the valve 120.

[67] Erosion of the fracturing window 112 from fracturing fluids and other fluids can potentially disrupt the seal of the valve 120, eliminating the effective prevention of fluid passage through the closed fracturing windows 112. However, for a structural solution of the adapter sleeve 110 of the present invention, it is possible to open several hydraulic fracture windows in a single coupling, which can help reduce erosion in comparison with structural solutions with the opening of only one hydraulic fracture window. This happens because several hydraulic fracturing windows can create a relatively large working cross-section of the flow, which effectively reduces the pressure drop of the fluid on the hydraulic fracturing window during hydraulic fracturing. A reduced pressure drop may result in a desired reduction in erosion.

[68] In FIG. 10 shows a portion of a borehole completion equipment 200 according to an embodiment of the present invention. Borehole completion equipment includes casing units 206a, 206b connected to the adapter sleeve assembly 210, hereinafter referred to as the adapter sleeve 210. In FIG. 11 shows an enlarged upper portion of the adapter sleeve 210, and FIG. 12 shows with enlargement the lower portion of the adapter sleeve 210. The adapter sleeve 210 shown in FIG. 11 comprises a mandrel 209, which may comprise a length of the casing link, a valve housing 203, and an exhaust housing 201. A valve, such as a sliding sleeve 220, is installed in the annular space 218 between the mandrel 209 and the valve housing 203. The sliding sleeve 220 is movable in the open position (shown in Fig. 10), providing communication between the inner diameter of the mandrel 209 and the outer frac windows 212B through the inner frac window 212A located in the mandrel 209. An annular space 218A passes angle of the perimeter of the mandrel and communicates with the annular space 218B between the exhaust casing 201 and the mandrel 209, which may be referred to as one annular space 218. The sliding sleeve 220 can be moved to the closed position (shown in Fig. 15), preventing hydraulic communication between the internal fracture window 212A and an external frac window 212B, both of which may be referred to as frac window 212. The sliding sleeve 220 effectively seals the annular space 218 in the upper portion 218A and 218B, thereby allowing the differential pressure to move between the two annular spaces of the sliding sleeve 220 between the open and closed positions. O-ring 215 can be used to connect valve casing 203 to exhaust casing 201. Grooves 218C in the mandrel under the o-ring provide satisfactory hydraulic communication past O-ring 215 between upper portion 218A and lower portion 218B of annular space 218. Alternatively, valve casing and exhaust casing may be one casing. In this embodiment, an o-ring is not required to connect two housings and grooves in the mandrel to provide hydraulic communication.

[69] In FIG. 12 shows that the lower portion of the exhaust casing 201 and the mandrel 209 have an annular space 218B between the two components. A lower nut 228 connects the lower end of the exhaust casing 201 to the mandrel 209 with sealing elements 222 that isolate the lower portion of the annular space 218B. The mandrel 209 includes an outlet 214 in communication with the annular space 218. In one embodiment, a plurality of outlets 214 are located around the mandrel 209. The mandrel may include one or more outlets 214B at locations other than the main outlets 214. B In operation, a buffer device, such as a breakable plug or cement-retaining grease, can fill each of the outlets to prevent cement or other unwanted substances from entering rotating arm space 218. In addition to the breakable stoppers detaining cement grease may be injected into the annular space 218 prior to running the completion equipment in the wellbore to prevent wicking of cement into the annular space 218, when the completion equipment is cemented in the wellbore. The outlet casing 201 may include a filling hole 227 for injecting grease into the annular space 218. Preferably, one of the outlet openings may have a diameter significantly smaller than the remaining outlet openings and not include a breakable plug. After the destructible plugs are destroyed, the outlet openings provide a differential pressure in the annular space 218 to open or close the valve 220, as described in detail above. In the event that cement enters the annular space 218 through the outlet openings 214, the outlet casing may include an auxiliary outlet (s) 214B further toward the wellhead along the mandrel 209, which may provide communication with the annular space 218.

[70] In FIG. 13 shows a facing down portion of the mandrel 209 without an outlet casing 201. Destructible plugs 231 are inserted into the outlet openings 214, 214B. Preferably, the collapsible plug is not inserted into the smallest outlet 214A, the diameter of which may be approximately 1/8 inch (3 mm). The outlet casing 201 is configured to create a predetermined distance between the fracture windows 212 and the outlet (s) 214. The outlets 214 may be located approximately two (2) meters from the fracture windows to create an adequate interval for the installation of a packer element to allow for the application of a differential pressure. Accurate installation of the packing element within half a meter in the wellbore is difficult. In addition, the position of the couplings relative to each other is often inaccurately known, mainly due to measurement errors when installing the completion equipment in the wellbore. The problem of accurately positioning the packing element in the wellbore due to several factors. One factor is the low accuracy of the equipment used to measure the force applied to the flexible tubing when lifting from the well, often the error is 1,000 pounds (454 kgfs) or more. Casing Coupling Location Profile, Position (133) FIG. 1 generally increases the lift force from the well by 2,000 pounds (908 kgf). In addition, the frictional force between the flexible tubing and the casing in a horizontal well is high and not constant when rising from the well. As a result, it may be difficult to establish the cause of the increase in strength when observed on the surface. The increase may be due to the retraction of the casing collar locator into the coupler or due to other forces of interaction between the flexible tubing and the completion equipment and / or proppant. The general approach used to increase the accuracy of determining the position of the packer element is to use short sections of pipe casings, a total of two (2) meters, above and below the adapter sleeve assembly. Thus, there are three or four couplings (depending on the configuration of the adapter) with a known spacing separate from the length of the standard casing string, which is typically thirteen (13) meters long. As a result of using short lengths of tubular casings fastened directly to the adapter coupling arrangement, measuring the absolute depth relative to the surface or relative to the recorded summary table is no longer required. However, this distance between the fracture window and the outlet may vary to accommodate various packing elements or configurations for applying a differential pressure, as should be clear to a person skilled in the art using this invention.

[71] In FIG. 9 shows a portion of a borehole equipment 200 according to an embodiment of the present invention, which includes a BHA inside a casing composed of a plurality of casing units 206 connected together by a plurality of adapter sleeves, such as a adapter adapter 210. An adapter adapter 210 in this an embodiment consists of a mandrel 209, a valve housing 203 and an exhaust housing 201. A valve, such as a sliding sleeve 220, is installed in the annular space 218 between the mandra Strongly 209 and valve housing 203. The sliding sleeve 220 is moved between an open position (shown in FIG. 9) providing communication between the interior diameter of the mandrel 209 and outer windows 212B through the internal fracturing the fracturing window 212A. The sliding sleeve 220 includes a clamping pin 221 configured to connect to a recess 223 (shown in FIG. 15) on the mandrel 209 to selectively hold the sliding sleeve 220 in the open position. Sealing elements 222 can be used to create a seal between the valve housing 203, the mandrel 209 and the sliding sleeve 220. The valve housing 203 may include one or more filling windows 217 allowing injection of grease or other cement blocking substances into the annular space 218 to prevent cement leakage if the completion equipment 200 is cemented in the wellbore.

[72] In FIG. 15 shows a cross section of the upper portion of the adapter sleeve 210 with the sliding sleeve 220 in the closed position. The shear pin 224 selectively holds the sleeve 220 in the closed position. The shear pin 224 can be used to hold the sliding sleeve 220 in the closed position during installation and reduces the likelihood of prematurely opening the sliding sleeve 220 (or valve 120). The shear pin 224 may be configured to shear and release the sliding sleeve 220 as a result of the application of a predetermined pressure drop, as should be clear to a person skilled in the art. The mandrel 209 may include one or more windows 230 that are mounted in the right place facing the wellhead of the side of the sliding sleeve 220 to assist in applying a differential pressure in the annular space 218A above the sliding sleeve 220 while moving the sliding sleeve 220 to an open position. After opening the sliding sleeve and hydraulic fracturing of the wellbore, the sliding sleeve 220 can move back to its closed position as a result of applying a differential pressure, as discussed above. Windows 230 in the mandrel 209 may allow fluid to escape from the annular space 218A when the sliding sleeve 220 passes fracture windows 212 when moved to the closed position. Mandrel 209 may include a recess 229 configured to connect to the clamping finger 221 and selectively hold the sliding sleeve 220 in a closed position until another differential pressure is applied. In the shown embodiment, the sliding sleeve 220 spans the entire perimeter of the mandrel 209. Alternatively, a plurality of sleeves can be used to selectively provide fluid communication with fracture windows 212.

[73] Clutch 210 may include one or more internal fracturing windows 212A, one or more external fracturing windows 212B, and one or more valve outlet openings 214 (shown in FIG. 12). Outer frac windows 212B intersect the annular space 218 and can be mounted in centralizers 216 along and outside the adapter sleeve 210 (as shown in FIG. 14). In an embodiment, the inner diameter of the adapter sleeve 210 may be approximately equal to or greater than the inner diameter of the casing. Thus, the annular space between the adapter sleeve 210 and the BHA is slightly throttled. One potential problem with this method is the reliable use of a packer, which is generally used in casing strings, which potentially have large variations in inner diameter between casing sections. The use of adapter sleeves 210 with windows can reduce this potential problem since adapter sleeves 210 with windows can be made with reduced variations in internal diameter, as well as having an ovality shape less than that of a typical casing string. These improvements provide improved reliability for proper sealing in couplings 210 with a conventional packer. In other embodiments, the inner diameter of the adapter sleeve 210 may be less than the inner diameter of the casing. However, the inner diameter of the adapter sleeve 210 may still correspond to the tolerance limits of the inner diameter of the casing. Clutch 210 may be attached to casing string 106 by any suitable device. In an embodiment, the adapter sleeve 210 may include two portions with an internal thread for connecting the threaded ends of the casing units 206b and 206c to the thread.

[74] As more clearly shown in FIG. 14, the fracture outer windows 212B may be located passing through centralizers 216, which may provide for the installation of the fracture outer windows 212B relatively close to the formation 107. If the casing is cemented in the wellbore, this may increase the chance of through or near-through passage through cement 105 windows 112 hydraulic fracturing. As shown in FIG. 14, one or more of the centralizers 216 may have direct contact with the open hole formation 107 of the wellbore, such as the centralizers 216 on the underside of a horizontal well, as should be apparent to one skilled in the art using the advantages of the present invention. A valve, such as a sliding sleeve 220, may be mounted in the desired location in the annular space with hydraulic communication with both the internal fracture windows 212A and the external fracture windows 212B. An annular space 218 may be located between the mandrel 209 and the outer valve housing 203. When the sliding sleeve 220 is in the closed position, as shown in FIG. 15, the passage of fluid through fracking windows 112 is prevented or reduced.

[75] As shown in FIG. 9, a packer 230 may be installed in the casing between fracture ports 212 and valve outlet openings 214. When the packer 230 is actuated, it is sealed on the inside diameter of the adapter sleeve 210 to prevent or reduce the passage of fluid further down the annular space of the wellbore. Thus, when the fluid flows from the surface down in the annular space between the borehole casing 104 and the BHA, a differential pressure is formed on the packer between hydraulic fracture ports 212 and valve outlet openings 214. A differential pressure can be used to open valve 220. The packer user, as shown as an example in FIG. 9 is illustratively provided with various tools and techniques for creating a differential pressure for opening and / or closing valves, as should be clear to a person skilled in the art. For example, a rotating monitor may potentially descend into the casing and be routed to valve outlets to create the differential pressure required to close the valve.

[76] As discussed above, during cementing, the casing is lowered into the well and cement is pumped to the bottom along the central channel of the casing and exits the end of the casing 104, filling the annular space between the casing 104 and the wellbore. To prevent flow of cement and / or fluids used during cementing, grease or other material may be injected into the annular space 218 of the adapter sleeve 210 before the casing is lowered into the wellbore. Destructible plugs may be inserted into valve outlet openings 214, and grease may be injected into the annular space through injection windows in valve casing 203 and exhaust casing 201. Injection windows may then be blocked.

[77] In FIG. 16 shows one technique used to open a sliding sleeve 220 for fracturing. The tubing string is used with a release tool having packers 140A, 140B to isolate the fracturing zone in the well. In FIG. 16 shows only a portion of a release tool that can be used with the coupling arrangement of the present invention. As shown in FIG. 16, the downhole packer 140B may be installed between fracking windows 212 and valve outlets 214 (shown in FIG. 12). This allows the sliding sleeve 220 to be opened by creating a pressure differential between the fracture windows 212 and the valve outlet openings 214 when pressure is generated in the area in the wellbore between the packers 140A, 140B. Pressure injection can be accomplished by supplying fluid to a flexible tubing and exiting through an opening 144 with a suitable pressure to open valve 220. The fluid used to open sliding sleeve 220 may be a fracturing fluid. A potential advantage of the arrangement of the flexible tubing and uncoupling tool FIG. 16 is that any proppant used during hydraulic fracturing can be isolated between the packers 140A and 140B from the rest of the annular space. In one embodiment, the sliding sleeve 220 may be configured to open at a predetermined differential pressure of the well above a desired fracture pressure. Thus, energy can accumulate in the flexible tubing before opening the sliding sleeve 220, and hydraulic fracturing can pass very quickly after opening the hydraulic fracture windows 212.

[78] A multi-zone fracturing method using the adapter sleeves 210 of the present invention is described below. The method may include lowering the casing 104 and the adapter sleeves 210 into the wellbore after drilling. Casing 104 and adapter sleeves 210 may be secured to the wellbore either by cementing or using packers for the uncased zone of the wellbore, as discussed above. After installing the casing in the borehole, the BHA, fastened to the end of the casing of the flexible tubing or casing from pipe links, can be lowered into the well. In an embodiment, the BHA may initially descend to the bottom of the bottom or close to the bottom of the bottom of the well. During the descent into the well, cams 132 (FIG. 3) are used with the profile not completely connecting and / or easily slipping past the recesses 134. For example, cams 132 can be configured with a small angle of sliding 131 from the side facing the bottom to provide more easy sliding past the recesses 134 with a small axial load when lowering into the well.

[79] After lowering the BHA to the required depth, the driller can begin lifting the string of the flexible tubing and BHA to the surface. The cams 132 may have a profile for connecting to a recess 134 with a steep angle 133 at the top of the cams 132, the result being an increase in the axial lifting force when pulling the cams 132 from the recesses. Moreover, the increase in resistance provides the driller with the detection of the right place in the well to install the packer 230, as discussed above. Creating a profile of cams 132, which provides reduced resistance when descending into the well and increased resistance when climbing from the well, is generally well known in the industry. After installing the packer 230 in the right place, the packer 230 can be activated to seal the borehole annular space between the BHA and the desired adapter sleeve 210 between the fracture windows 212 and the valve outlet 214.

[80] After sealing the borehole annulus to the sleeve 210 in a desired borehole annulus may be pumped from the surface of the pressure to a pressure sufficient to open the valve 220. Suitable pressure may range, e.g., from about 100 lb / ⁱⁿ² (0.7 MPa ) to about 10,000 lb / ⁱⁿ² (70 MPa), from about 500 lb / ⁱⁿ² (3.5 MPa) to about 1000 lbs / ⁱⁿ² (7 MPa), 1500 lb / ⁱⁿ² (10.5 MPa) or more. As discussed above, a suitable pressure may exceed the required fracturing pressure to facilitate rapid fracturing.

[81] After opening the fracturing windows 212, fluids can be pumped through the fracturing windows 212 into the wellbore. Fracturing may be initiated, and fracturing fluids may be injected into the wellbore to fracture. If required, a proppant, such as a sand suspension, can be used in the method. Proppant can fill the cracks and keep them open after stopping hydraulic fracturing. After hydraulic fracturing, the BHA can be used to remove any unwanted proppant / hydraulic fracturing fluid from the wellbore.

[82] In multi-zone wells, the above fracturing method may be repeated for each zone of the well. Thus, the BHA can be installed in the next adapter sleeve 210, the packer can be driven, the hydraulic fracturing windows 212 open and hydraulic fracturing is performed. The method may be repeated for each zone from the bottom up along the wellbore. After hydraulic fracturing, oil can escape from cracks through hydraulic fracturing windows 212 of adapter couplings 210 and into the well. When a BHA is used, as shown in FIG. 1, the first treatment may take place at the bottom of the bottom of the well, and each subsequent treatment may take place with decreasing depth in the well. Hydraulic fracturing for each zone can all be performed during one BHA trip with the minimum time spent between hydraulic fracturing of each zone. The coupling configurations of the present invention, which are installed in the right place in the area above the current treatment, are under pressure from the current treatment of the wellbore. This pressure may periodically be limited by the design casing pressure. However, there is no risk of prematurely opening the valves of this coupling arrangement, since the pressure is balanced on the valves. The valves of the present invention can only be opened by the differential pressure between the fracturing window and the valve outlet. Additionally, the present invention provides for the efficient use of fluid in a hydraulic fracturing process because the displacing fluid for the current fracturing zone can act as a pack fluid for the next treatment zone.

[83] The design of the adapter sleeve 210 of the present invention can potentially close the valve 220 after it has been opened. This may be preferred in embodiments if some zones in the multi-zone well begin to produce water, or some other undesirable fluids. If water supply zones can be detected, couplings associated with such zones can be closed to prevent unnecessary fluid flow from the zones. This can be accomplished by isolating the valve outlet 214 and then pressurizing to close the valve 220. For example, the uncoupling tool can be used similarly to the embodiment of FIG. 16, except that a packer 140A may be installed between fracking windows 212 and valve outlet openings 214, and a lower packer 140B may be installed on the far side of the valve outlet openings 214 from the packer 140A. When pressure builds up in the area between the packers, high pressure is created at the valve outlets 214, which causes the sliding sleeve 220 to close. As discussed above, the sliding sleeve 220 may include a clamping finger 221, which may help to keep the sliding sleeve 220 in the closed position.

[84] In FIG. 17-19 show a portion of wellbore completion equipment 300 according to an embodiment of the present invention. Borehole completion equipment 300 may include BHA 302 installed at a desired location within the casing. The casing may consist of various sections and connectors connected together, for example, shortened pipe links 306, sub 315 and 317 and a casing 310 with windows, as well as conventional casing pipes, as should be clear to a person skilled in the art using the advantages of this invention .

[85] In FIG. 17 shows a shortened pipe link 306 connected to one end of the casing 310 with windows upper sub 315. The other end of the casing 310 with windows is connected to another shortened pipe link 306 lower sub 317. The shortened pipe links 306 can connect to conventional casing pipes, forming sections of the casing the columns. The casing sections are fastened together by a thread 343. The threaded connections and the configurations of the casing sections are shown illustratively since various connecting means and any suitable configurations can be used in essence. For example, the casing 310 with windows can be connected directly to the shortened pipe links 306 without the use of connecting sub 315, 317.

[86] The casing 310 with windows includes at least one fracturing window 312 providing fluid communication between the spaces inside and outside the casing 310. The sliding sleeve 320 may have a sliding connection with the inner surface of the casing 310. In the initial position, as shown in FIG. . 17, the sliding sleeve 320 can be installed in the desired location, while the seals 322 prevent hydraulic communication through the window 312. The cutting device 324 can be used to selectively hold the sliding sleeve 320 in its initial closed position. The shear device 324 may be a shear pin, a collapsing ring, or other device configured to selectively release the sliding sleeve 320 from the housing 310 as a result of the application of a predetermined force that can be applied by hydraulic pressure, as discussed in detail below.

[87] In FIG. 18 shows a BHA 302 connected to a flexible tubing 342, lowered into the casing and installed in the right place in the casing 310 with windows. The casing collar locator can be used to set the BHA 302 to the desired location in the casing. For example, the bottom sub 317 may include a profile 333 configured to come into contact with the casing collar locator profile 332 for positioning the BHA 302 in a specific casing 310 with windows along the casing.

[88] BHA 302 includes a packer 330 that can be activated to seal the annular space between the outer surface of the BHA 302 and the inner diameter of the sliding sleeve 320 of the casing 310 with windows. BHA 302 also includes a latch 350 that can be pressed against the sliding sleeve 320. Applying pressure in the flexible tubing is used to activate the latch 350 and install it on the sliding sleeve 320, as well as to install the packer 330. A potential advantage of the BHA embodiment 302 is that BHA 302 can be mounted in casing 310 without using a bayonet groove that requires downward movement, upward movement, and then downward movement of the flexible tubing 342 for installing the BHA 302. This repeated cyclic up and down movement of the flexible tubing 342 for installing the BHA 302 may cause the flexible tubing 302 to fail too quickly. In comparison, the present embodiment of the BHA 302 and the casing 310 with windows and a sliding sleeve 320 provides less movement of the flexible tubing 342. After opening the sleeve 320, as discussed below, the BHA 302 can be released, moved up in the casing to the next desired area and mounted in the selected casing 310 without any cyclic up and down movement of the flexible tubing 342.

[89] After installing the retainer 350 to fasten the BHA 302 with the sliding sleeve 320 and activating the packer 330, fluid may be pumped into the casing, creating a pressure drop across the packer 330. When the specified pressure drop is reached, the shearing device 324 must be cut off and at the same time release the sliding sleeve 320 from the casing 310. The cutting device 324 may be cut-off at a given pressure drop, as should be clear to a person skilled in the art.

[90] After the sliding sleeve 320 is released by the shear device from the housing 310, an increase in pressure drop across the packer 330 should move the BHA 302, which is bonded to the slip sleeve 320, down the casing. In this way, the sliding sleeve 320 can be moved from the closed position shown in FIG. 18 to the open position shown in FIG. 19. Alternatively, the sliding sleeve 320 can be moved to the open position by applying a downward force to the BHA 302 by the flexible tubing 342 or by applying hydraulic pressure in conjunction with the downward force from the flexible tubing 342.

[91] After moving to the open position, the sliding sleeve 320 can be selectively locked in the open position. For example, the sliding sleeve 320 may include an expandable device 325, such as a snap ring or a locking cam, that expands into a groove 326 in the inner casing 310, selectively locking the sliding sleeve 320 in the open position. In the open position, fluid from the interior of the casing 310 can communicate with the space outside the casing 310, providing fracturing and / or processing of the near-wellbore zone of the formation adjacent to the window 312.

[92] A plurality of windowed shrouds 310 with sliding sleeves 320 may be installed in the desired location along the length of the casing at locations where fracturing is required. After hydraulic fracturing using the first casing 310 with windows and sliding sleeve 320, similar to the above, BHA can move to the second casing 310 with windows containing the second sliding sleeve 320, where hydraulic fracturing is carried out in second place in the well. The method can be repeated until the completion of the required hydraulic fracturing in the well.

[93] The use of BHA 302 in conjunction with a casing 310 with windows and a sliding sleeve 320 may provide a system for selectively treating the near-wellbore zone to enhance inflow and / or treatment of the wellbore, inexpensive in comparison with other systems. For example, the configuration of an embodiment may allow the use of lengths of varying lengths of casing and sliding sleeves to install multiple windows 312 along the casing for the desired more extensive contact with the formation. Additionally, as confirmed, the embodiment can provide a large internal diameter of the stream in comparison with other hydraulic fracturing / treatment systems.

[94] The methods described herein include both a hydraulic fracturing method through an annular space in which hydraulic fracturing fluid is pumped into the borehole annular space and a hydraulic fracturing method using a flexible tubing. A potential problem in some fracturing methods through annulus is that often the annular volume of the borehole is larger than the processing buffer, especially when the steps become smaller and are closer to each other. If additional fluids or time is not required, it may become necessary to pump the slurry for subsequent processing to displace fluids from the processed treatment. As a result, an additional risk of processing may appear since the return to the initial state, the movement of the BHA and the initiation of the next fracture are performed with a suspension already in the well. In addition, in this method, it is possible to start and stop the injection of the suspension, which can complicate the work, increase the risk and reduce the quality of processing.

[95] Embodiments of the present invention by pumping processing fluids through a flexible tubing may have the advantage that the volume of the flexible tubing is usually less than the volume of the processing bundle, and therefore additional time and additional fluid may not be required. In addition, since the cross-sectional area of the flexible tubing is smaller than that of the annular space between the wellbore and the flexible tubing, the fluid velocities are generally higher and the proppant is less prone to precipitation and remains in the flexible tubing the pipe. This may be preferred since residual proppant may interfere with processing. For example, if proppant is introduced into the treatment too early, when a pack of fluid is pumped, the proppant can block the crack, preventing the crack from expanding and causing proppant to fall out. Injection of the processing fluid into the flexible tubing may also result in a decrease in the sand content in the wellbore, which may provide easier movement and improved functioning of the BHA on the flexible tubing.

[96] In FIG. 20 shows well completion equipment 400 designed for fracturing using a flexible tubing according to an embodiment of the present invention. The casing arrangement 404 comprises a plurality of casing units 406A and 406B and at least one adapter sleeve 410 mounted to couple the casing units together in a manner similar to the other embodiments described herein. At least one adapter sleeve 410 comprises at least one fracturing window 412 configured to provide hydraulic communication between the outer surface of the sleeve and the internal casing flow path, and the arrangement of the couplers. For example, the adapter sleeve may be any of the adapter couplers containing a fracturing window described herein. If desired, the adapter sleeve may include a plurality of centralizers, such as those shown in FIG. 4 and 5, where at least one fracturing window passes through centralizers. When using adapter couplings, including hydraulic fracturing windows, in each zone of a multi-zone well, the need to perforate all zones before hydraulic fracturing can be reduced or eliminated. In another embodiment, the couplings may be similar to those shown in FIG. 17-19 of an adapter sleeve 310 with windows and a sliding sleeve 320 described above.

[97] A segment of the flexible tubing 442 is set to the desired location in the casing arrangement 404. Flexible tubing 442 includes an internal flow path for supplying fluid to or from a surface. An annular space 450 is formed between the flexible tubing 442 and the casing arrangement 404. Layout 402 of the bottom of the drill string is connected to a flexible tubing. The bottom hole assembly 402 includes a fracturing hole 444 configured to provide hydraulic communication between the internal flow path of the tubing 442 and the annular space 450. As shown, a plurality of fracturing holes can be used. Fracturing holes can be large enough so that increased costs can be obtained without an unacceptable pressure drop when the processing fluid exits the BHA. Suitable holes have sizes in the range of, for example, from about 0.5 to about 0.75 inches (13-19 mm) wide and from about 2 inches to about 4 inches (51-102 mm) in length. The size of the holes may vary depending, inter alia, on the number of holes.

[98] BHA 402 also includes a packer 430. Any suitable packer may be used. Examples of suitable packers include those used in SURESET ^™ BHA, manufactured by Baker Hughes Incorporated, Houston Texas, or MONGOOSE ^™ BHA, manufactured by NCS Energy Service Inc., SPRING, Texas.

[99] In an embodiment, the second packer is not installed in the annular space above the first packer 430, as in the embodiment where the packer is the uncoupling tool shown in FIG. 7. Dissociative tools can be used for isolation at each stage, when processing fluids are pumped through a flexible tubing, and different stages with perforation before fracturing. Although uncoupling tools have specific advantages, a problem when using the uncoupling tool is the possible complication of circulating the processing fluid past the upper lip seal or the casing of the uncoupling tool to remove excess proppant. In addition, twin packers have large outer diameters and can easily be picked up when working in suspensions. The release tool also requires satisfactory cementing for insulation at each stage. Since the casing over the uncoupling tool does not experience hydraulic fracturing pressure, there is a risk of either a possible destruction of the casing or a possible exit of the processing fluid from the casing in the next group of perforations located above the current treatment site.

[100] The packers used in the embodiment shown in FIG. 20 may have relatively small diameters compared to uncoupling tools with lip seals, and therefore their seizure is less likely. In an embodiment, the outer diameter of the packers may, for example, be less than about 0.25 inch (6 mm) to about 0.75 inch (19 mm) of the inner diameter of the casing. Additionally, since the uncoupling tool is not used in this embodiment, pressure is pumped over the packer in the annular space of the wellbore over the entire hydraulic fracturing time, which may reduce the dependence on cementing to isolate zones.

[101] In FIG. 20, when the BHA 402 descends into the casing assembly 404 on the flexible tubing 442, the packer 430 can be mounted in the desired location near the adapter 410 to provide contact with the adapter 410 when the packer expands to isolate the annular portion 450 above by the packer 430 from the portion 450 of the annular space below the packer 430. With this method, after expanding the packer, fluid passing through the flexible tubing into the annular space 450 through the openings 444 can cause hell pressure on the packer 430, as described above and shown in FIG. 2.

[102] In FIG. 21 shows another embodiment of the present invention similar to that shown in FIG. 20, except that the BHA 402 includes an abrasive perforator 452. Abrasive perforators are generally well known in the art. The layout of the bottom of the drill string is configured to isolate the fluid stream in the internal flow path of BHA 402 between the abrasive drill 452 and the fracture hole 444, which is discussed in more detail below. An abrasive punch acts as a backup option in case of failure of hydraulic fracture windows in the adapter sleeve. If the slip sleeve in the adapter sleeve does not open, or if the formation adjacent to the slip sleeve is so tight that no fractures from fracturing pressure occur, the BHA can move several feet (1 foot = 0.3 m) and the casing can be perforated. Hydraulic fracturing can then be carried out through newly created perforations in the casing.

[103] As also shown in FIG. 20, the present invention also provides a method for completing a hydrocarbon production wellbore. The method comprises launching a flexible tubing 442 into a casing assembly 404. The transition sleeves 410 of the casing assembly 404 comprise a plurality of holes, such as a first fracture window 412 and a valve outlet 414.

[104] As discussed above, the bottom of the drill string assembly 402 bonded to the flexible tubing 442 includes a packer 430. When the flexible tubing is lowered into the well, the packer 430 can be set in place so that when the packer 430 is driven, the packer 430 is in contact with at least one adapter sleeve 410 to isolate the annular portion 450 above the packer 430 from the annular portion 450 below the packer 430. This allows fluid to form flowing down the flexible tubing 442, the differential pressure on the packer 430, which can open the fracture window 412.

[105] If necessary, the couplings may be so designed that mechanical force can be used in combination with fluid pressure to open and / or close fracture windows 412. For example, a flexible tubing may be used to apply pressure to the sleeve, similar to that described above and shown in FIG. 18 and 19.

[106] After opening the fracturing windows 412, the wellbore may be fractured by supplying fracturing fluid through the fracturing windows 412. This method can be repeated many times to perform multi-zone hydraulic fracturing.

[107] In an embodiment where the bottom of the drill string assembly 402 comprises an abrasive perforator 452, the method may further comprise isolating a fluid passage between the abrasive cutting perforator and the fracturing hole. This may be accomplished using any suitable technique. For example, the bottom hole assembly 402 may include a mounting profile, such as a ball socket (not shown), narrowing the diameter of the internal flow path between the abrasive cutting punch 452 and holes 444. A ball, dart, or other device (not shown) for blocking The flow paths of the flexible tubing can be pumped down the flexible tubing so that the device fits into the ball socket between the abrasive cutting punch and the fracture hole, while isolating the abrasion a live punch 452 from holes 444. Such profile systems for mounting and a ball or dart are generally well known in the art.

[108] Blocking the flow path of the flexible tubing allows the abrasive slurry to be pumped down the flexible tubing to exit the abrasive cutting punch. Upon completion of the abrasive cutting punch, the flow in the flexible tubing and BHA 402 can be reversed to raise the ball to the surface and then restore the fluid from the flexible tubing through hole 444. Instead of the profile system for installation and the ball or dart, various other mechanisms can be used to isolate the abrasive cutting punch 452 from the calibrated hole 444, known to the person skilled in the art, taking advantage of this invention tions.

[109] Although various embodiments are shown and described, the invention is not limited to them and, as is understood, includes all modifications and variations known to those skilled in the art.

Claims (21)

1. Equipment for completing a wellbore, comprising:
a casing arrangement comprising a plurality of casing links and at least one adapter sleeve installed to connect the casing links, at least one adapter sleeve comprising a tubular body having an internal flow path and at least one fracturing window made with the possibility of creating a hydraulic communication between the outer surface of the adapter sleeve and the internal flow path;
a portion of the flexible tubing installed in the casing arrangement, the flexible tubing comprising an internal flow path, with an annular space formed between the flexible tubing and the casing arrangement;
the layout of the bottom of the drill string connected to a flexible tubing, and the layout of the bottom of the drill string contains:
hydraulic fracturing hole, configured to create a hydraulic communication between the internal path of the flow of the flexible tubing and the annular space, and
the packer installed in the right place to contact at least one adapter sleeve when the packer expands, wherein the packer is configured to isolate the annular space above the packer from the annular space below the packer, so that a fluid flowing down the flexible tubing pipe can flow out of the hydraulic fracturing hole, creating a pressure drop on the packer to open the hydraulic fracturing window. 2. The completion equipment according to claim 1, in which the layout of the bottom of the drill string further comprises an abrasive perforator, and the layout of the bottom of the drill string is configured to isolate the fluid flow between the abrasive perforator and the fracturing hole in the flexible tubing. 3. The completion equipment according to claim 1, in which the layout of the bottom of the drill string is made without an abrasive perforator. 4. The completion equipment according to claim 1, wherein the packer is not a dual packer. 5. The completion equipment according to claim 1, wherein the second packer is installed outside the annular space above the first packer. 6. The completion equipment according to claim 1, wherein the adapter sleeve further comprises:
at least one valve hole in the coupling crossing the fracturing window;
at least one outlet installed in the right place to create a hydraulic communication between the valve hole and the internal flow path; and
at least one valve installed in the valve hole for opening and closing the fracturing window, the valve being configured to open when a pressure differential is created between the fracturing window and the valve outlet. 7. The completion equipment according to claim 6, wherein the at least one valve is a sliding sleeve moving in the valve hole. 8. The completion equipment according to claim 7, wherein the valve is a longitudinal stem. 9. The completion equipment according to claim 6, further comprising a plurality of centralizers protruding from the tubular body. 10. The completion equipment according to claim 9, in which at least one fracturing window passes through the centralizers. 11. The completion equipment according to claim 1, wherein the adapter sleeve further comprises a sliding sleeve that is slidingly connected to the inner surface of the tubular body, the sliding sleeve being adjustable between the first position and the second position, the sliding sleeve is configured to prevent hydraulic communication through the fracture window in the first position and providing hydraulic communication through the hydraulic fracturing window in the second position. 12. The completion equipment according to claim 11, in which the layout of the bottom of the drill string further comprises a latch configured to fasten the layout of the bottom of the drill string with a sliding sleeve. 13. The method of completing the trunk of a hydrocarbon production well, in which:
the flexible tubing is lowered into the wellbore casing arrangement, the casing arrangement comprising a plurality of casing units and one or more adapter couplings installed to connect the casing units together, wherein the first adapter sleeve of one or more adapter sleeves comprises a first fracturing window;
pumping fluid through a flexible tubing to apply a differential pressure to open the first casing string fracture window;
hydraulic fracturing of the wellbore is performed by supplying a hydraulic fracturing fluid through the first hydraulic fracturing window, wherein
the flexible tubing contains an arrangement of the bottom of the drill string containing a packer and a hydraulic fracturing hole, and in the method, a packer is additionally installed to provide contact with at least one adapter sleeve and is actuated to isolate a portion of the annular space above the packer from the annular portion under the packer so that the fluid flowing down the flexible tubing can create a pressure drop on the packer that can open the hydraulic fracture window yow. 14. The method according to p. 13, in which the first adapter contains many holes, at least one of the many holes on the first adapter is the first fracturing window, and the fracturing window is configured to open and close using a pressure differential between the two holes on first adapter sleeve. 15. The method according to p. 13, in which the second packer is installed outside the annular space above the first packer. 16. The method according to p. 13, in which the layout of the bottom of the drill string further comprises an abrasive perforator, while further isolating the passage of fluid between the abrasive perforator and the fracturing hole. 17. The method according to p. 16, in which the isolation of the fluid passage comprises pumping a ball through a flexible tubing, and the ball rises between the abrasive perforator and the fracturing hole. 18. The method according to p. 13, in which the fluid is additionally pumped through a flexible tubing for applying a differential pressure to open a second fracturing window. 19. The method according to p. 18, in which additionally carry out hydraulic fracturing of the wellbore by supplying a fluid fracturing through the second hydraulic fracturing window. 20. The method according to p. 13, in which mechanical force is used in combination with pressure to open the first fracturing window. 21. The method of completing the trunk of a hydrocarbon production well, in which:
the flexible tubing is lowered into the wellbore casing arrangement, the casing arrangement comprising a plurality of casing units and one or more adapter couplings installed to connect the casing units together, wherein the first adapter sleeve of one or more adapter sleeves comprises a first fracturing window;
pumping fluid through a flexible tubing to apply a differential pressure to open the first casing string fracture window;
hydraulic fracturing of the wellbore is performed by supplying hydraulic fracturing fluid through the first hydraulic fracturing window, and mechanical force is used in combination with pressure to open the first hydraulic fracturing window.

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