BACKGROUND
1. Field of the Disclosure
This disclosure relates generally to apparatus and methods for completing a wellbore for the production of hydrocarbons from subsurface formations, including fracturing, gravel packing and flooding selected zones and for communicating information in real-time about various downhole operations.
2. Background of the Art
Wellbores are drilled in subsurface formations for the production of hydrocarbons (oil and gas). Modern wells can extend to great well depths, often more than 6000 meters (about 20,000 ft.). Hydrocarbons are trapped in various traps in the subsurface formations at different depths. Such sections of the formation are referred to as reservoirs or hydrocarbon-bearing formations or zones. Some formations have high mobility, a measure of the ease of the hydrocarbons flow from the reservoir into a well drilled through the reservoir under natural downhole pressures. Other formations possess low mobility and the hydrocarbons trapped therein are unable to move with ease from the reservoir into the well. Stimulation methods are typically employed to improve the mobility of the hydrocarbons through the reservoirs. One such method, referred to as fracturing (also referred to as “fracing” or “fracking”), is often utilized to create cracks in the reservoir to enable the fluid from the formation (formation fluid) to flow from the reservoir into the wellbore. To sand control, frac-pacing and gravel packing multiple zones, an assembly containing an outer string with an inner string therein is run in or deployed in the wellbore. The outer string is conveyed in the wellbore with a tubing attached to its upper end and it includes various devices corresponding to each zone to be fractured for supplying a fluid with proppant to each such zone. The inner string (also referred to as the “service string”) includes devices or tools attached to a tubing (which tubing can extend over 1,000 meters (about 3,000 feet) to perform a number of operations during treatment or service operations, including, but not limited to, setting an upper packer with a packer setting tool, setting a tool at selected locations of the outer string, setting packers, opening and closing valves, flowing fracture fluid from the inner string into the production zones via a frac port, and performing reverse flow and return flow operations. In such systems, It is desirable to obtain real-time information about the various operations performed in a wellbore using the inner string and outer string, including determining location of a device or element downhole, setting a device, fluid flow, temperature and pressure profiles, quality of the performed operations, etc. from various location along the inner string, including locations below the frac port. However, commercially utilized inner strings that include a packer setting tool and frac port are not available with a control line or communication link that runs from the surface to a location below the frac.
The disclosure herein provides systems and methods for use in wellbore operations that include a two-way communication system for providing real-time information between a surface location and downhole devices and operations, including information from locations below the frac port.
SUMMARY
In one aspect, an apparatus for use in a wellbore for performing a treatment operation is disclosed that in one non-limiting embodiment may include an inner string that further includes a first tubular having a first communication link, and a service tool including a cross-over tool having a fluid flow passage therein for supplying a treatment fluid under pressure from an inside of the service tool to an outside of the service tool, and wherein the service tool includes a second communication link operatively coupled to the first communication link and wherein the second communication link runs across or through a through passage in the cross-over tool that is protected from direct flow of the fluid under pressure from the inside of the service tool to the outside of the service tool.
In another aspect, a method of performing a treatment operation in a wellbore is disclosed that in one non-limiting embodiment may include: providing an outer string; providing an inner string for placement inside the outer string, wherein the inner string includes a cross-over tool for supplying fluid under pressure from the inner string to the outer string; and running a communication link across or through the crossover tool that is protected from direct flow of the fluid from the inner string to the outer string through the cross-over tool.
Examples of the more important features of a well treatment system and methods that have been summarized rather broadly in order that the detailed description thereof that follows may be better understood, and in order that the contributions to the art may be appreciated. There are, of course, additional features that will be described hereinafter and which will form the subject of the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
For a detailed understanding of the apparatus and methods disclosed herein, reference should be made to the accompanying drawings and the detailed description thereof, wherein like elements are generally given same numerals and wherein:
FIG. 1 shows an exemplary cased hole multi-zone wellbore system configured for a well treatment operation such as frac-packing. The wellbore system is shown to include a wellbore that has been lined with a casing
FIG. 2 shows certain details of an exemplary embodiment of the packer setting tool shown in FIG. 1 with the routing of the control line there through, according to one non-limiting embodiment of the disclosure;
FIG. 2A shows an exploded view of a section of FIG. 2;
FIG. 3 shows certain details of an exemplary cross-over tool shown in FIG. 1 with the routing of the control line there through, according to one non-limiting embodiment of the disclosure;
FIG. 4 shows a section of an exemplary cross-over tool shown FIG. 3 through which the control line shown in FIG. 3 may be routed; and
FIG. 5 shows placement of certain sensors in the system of FIG. 1 for determining certain parameters of interest in real time relating to downhole operations.
DETAILED DESCRIPTION OF THE DRAWINGS
FIG. 1 is a line diagram of a section of an exemplary multi-zone wellbore system 100 that is shown to include a wellbore 101 formed in formation 102 for performing a treatment operation therein, such as fracturing the formation (also referred to herein as fracing or fracking), frac-packing, gravel packing, etc. and for determining, in real time or near real time, parameters of interest relating to such operations from sensors deployed in the system 100 and taking actions in response to such determined parameters of interest. The wellbore 101 is lined with a casing 104, such as a string of jointed metal pipe sections, known in the art. The space or annulus 103 between the casing 104 and the wellbore 101 is filled with cement 106. The system 100 is described herein in reference to a cased-hole; however, the concepts, apparatus and methods as described herein or with obvious modifications may equally be utilized for open holes. The particular embodiment of FIG. 1 is shown for selectively treating one or more zones in any selected sequence or order. However, wellbore 101 may be configured to perform other treatment or service operations, including, but not limited to, gravel packing and flooding a selected zone to move fluid in the zone toward a production well (not shown). The formation 102 is shown to include multiple zones Z1-Zn (also referred to as production zones) which may be fractured or treated for the production of hydrocarbons therefrom. Each such zone is shown to include perforations that extend from the casing 104, through cement 106 and to a certain depth in the formation 102. In FIG. 1, Zone Z1 is shown to include perforations 108a, Zone Z2 to include perforations 108b, and Zone includes Zn to include perforations 108n. The perforations provide fluid passages for fracturing corresponding zones. The perforations also provide fluid passages for formation fluid 150 to flow from the formation 102 to the casing 104. The wellbore 101 includes a sump packer 109 proximate to the bottom 101a of the wellbore 101. [open hole mentioned in paragraph 0009 below]
After casing, cementing, sump packer deployment, perforating and cleanup operations, the wellbore 101 is ready for treatment operations. Although system 100 is described in reference to fracturing and gravel packing production zones, the concepts, apparatus and methods as described herein or with obvious modifications may also be utilized for other well treatment operations, including, but not limited to, fracturing and gravel packing. Furthermore, the concepts, apparatus and methods disclosed herein may equally be utilized for open hole applications. The formation fluid 105 is at the formation pressure (P1) and the wellbore 101 is filled with a fluid 152, such as completion fluid, which fluid provides hydrostatic pressure (P2) inside the wellbore 101. The hydrostatic pressure P2 is greater than the formation pressure P1 along the depth of the wellbore 101, which prevents flow of the fluid 105 from the formation 102 into the casing 104 and prevents blow-outs.
Still referring to FIG. 1, to fracture (treat) one or more zones Z1-Zn, a system assembly 110 is deployed in the wellbore 101, which includes an outer string 120 and an inner string 160 placed inside the outer string 120. The outer string 120 includes a pipe 122 and a number of devices associated with each of the zones Z1-Zn for performing treatment operations. In one non-limiting embodiment, the outer string 120 includes a lower packer 124a, an upper packer 124m and intermediate packers, such as packer 124b. The lower packer 124a isolates the sump packer 109 from hydraulic pressure exerted in the outer string 120 during fracturing and sand packing of the production zones Z1-Zn. In one aspect, packers 124a-124m may be hydraulically set or deployed packers. In another aspect, packers 124a-124m may be mechanically set or deployed. Still referring to FIG. 1, the outer string 120 further includes a screen adjacent to each zone Z1-Zn. For example, screen S1 is shown placed adjacent to zone Z1, screen S2 adjacent zone Z2 and screen Sn adjacent to zone Zn. The lower packer 124a and intermediate packer 124b are deployed to isolate zone Z1 from the remaining zones. Other zones are similarly isolated for treatment operations. Each packer has an associated packer setting or activation device, such as packer setting device 125a for packer 124a, packer setting device 125b for packer 124b and packer setting device 125m for packer 124m. In the case of a hydraulically-activated packer, any suitable device known in the art, including a piston device, may be utilized as the hydraulic activation device, and in case of a mechanically-activated packer, the device may include a mechanical member that is moved to set the packer.
In one aspect, each screen has one or more associated flow control devices, such as sliding sleeve valves 132a and 132b shown on screen S1. Other screens have similar devices. The outer string 120 also includes, for each zone, a flow control device, referred to as the slurry outlet or a gravel exit, such as a sliding sleeve valve or another valve, uphole or above its corresponding screen to provide fluid communication between the inside 120a of the outer string 120 and its corresponding zone. FIG. 1 shows an exemplary slurry outlet 140a for zone Z1 between screen S1 and the intermediate packer 124b.
Still referring to FIG. 1, the inner string 160 includes an upper section 160a that includes a tubular 161 made by joining pipe sections (such as drill pipe) and a lower section 150 (referred to as the service tool) connected to the upper section 160a. The service tool 150 includes a pipe or tubular 158, which may be a flush joint tubular, known in the art. The service tool 150 also may include an interface sub 154 attached to the bottom end 161a of the tubular 161 to provide a connection for a communication link 182 in the tubular 161 to a communication link or line 184 in the service tool 150, as described in more detail in reference to FIGS. 2-5. The phrase “communication link” or “communication line” means a link for communicating signals, data and/or power from one location to another. The communication link may be any suitable link, including, but not limited to, electric lines, fiber optic lines and other links, such as acoustic links or a combination of such links.
Still referring to FIG. 1, the service tool 150 includes a packer setting tool 156 for setting the upper packer 124m. In a multi-zone well system, the tubular 158 may extend to over 3,000 feet. The service tool 150 further includes an opening shifting tool 162 and a closing shifting tool 164 along the lower end 160a of the inner string 160. The inner string 160 further may include a reversing valve 166 that facilitates the removal of treatment fluid from the wellbore after treating each zone, and an up-strain locating tool 168 for locating one or more locations uphole of a set-down location, such as a locations 194b for zone Z1 when the inner string 160 is pulled uphole, and a set down tool or set down locating tool 170. In one aspect, the set down tool 170 may be configured to locate each zone and then set down the inner string 160 at each such location for performing a treatment operation. The service tool 150 further includes a cross-over tool 174 (also referred to herein as the “frac port”) for providing a fluid path 175 between the inner string 160 and the outer string 120. In one aspect, the frac port 174 also includes flow passages 176 therethrough, which passages may be gun-drilled through the frac port 174 to provide fluid communication between space 172a below the frac port 174 and space 172b above the frac port 174. The size of passages 176, however, are sufficient to provide fluid flow and thus pressure communication between spaces 172a and 172b.
To perform a treatment operation in a particular zone, for example zone Z1, lower packer 124a and upper packer 124m are set or deployed. Setting the upper packer 124m and lower packer 124a anchors the outer string 120 inside the casing 104. The production zone Z1 is then isolated from all the other zones. To isolate zone Z1 from the remaining zones Z2-Zn, the inner string 160 is manipulated to cause the opening tool 164 to open a monitoring valve 133a in screen S1. The inner string 160 is then manipulated (moved up and/or down) inside the outer string 120 so that up-strain locating tool 168 locates a profile 194b. The set down tool 170 is then manipulated to cause it to set down in the set down profile 194a. When the set down tool 170 is set down at location 194a, the frac port 174 is adjacent to the slurry outlet 140a. The packer 124b is then set to isolate zone Z1. Once the packer 124b has been set, frac sleeve 140a is opened to supply slurry or another fluid to zone Z1 to perform a fracturing or a treatment operation. Once zone Z1 has been treated, the treatment fluid in the wellbore is removed by closing the reversing valve 166 to provide a fluid path from the surface in the space (or annulus) between the outer string 120 and the inner string 160 so that a fluid supplied from the surface into such annulus will cause the treatment fluid to move to the surface, which process is referred to as reverse circulation or reversing. After reverse circulation, the inner string 160 may then be moved to set down device 170 at another zone for treatment operations.
Still referring to FIG. 1, as described earlier, the inner string 160 includes a control line, also referred as the “communication link” for providing communication between a location in the service tool and the surface. The phrase “control line” or “communication link” means a link for communicating signals, data and/or power from one location to another. In one non-limiting embodiment, a communication link 182, which may be a conductor, runs through the tubular 161, referred to as the wired pipe in the art. Interface sub 154 connects the communication link 182 to a communication link 184 associated with the service tool 150 that runs to a control circuit 185 below the cross-over tool 174. In one non-limiting embodiment, the communication link 184 passes through the packer setting tool 156, as described in more detail in reference to FIG. 2. The communication link 184 then runs along the tubing 158 and then through the cross-over tool 174, as described in more detail in reference to FIGS. 3 and 4. The communication link 184 then may pass other devices, such as the set down locating tool 170, the up-strain locating tool 168, reversing valve 166 and then along the tubing 158 below such devices. The control circuit 185 may be placed at any suitable location in the communication link 184 to receive signals from various sensors placed in the casing 104, outer string 120 and the inner string 160, as described in more detail in reference to FIG. 5. An exemplary packer setting tool 200 and a manner for running the communication link 184 through such a packer is described below in reference to FIG. 2.
FIG. 2 shows an exemplary embodiment of a packer setting tool 200 configured to set a packer 280. FIG. 2A shows an exploded view of a section of FIG. 2. Referring now to FIGS. 2 and 2A, in one aspect, the packer setting tool 200 may be utilized as the packer setting tool 156 for setting the upper packer 125m shown in system 100 of FIG. 1. The packer setting tool 200 includes an upper connection 201 that connects the packer setting tool 200 to the interface sub 154 (FIG. 1) and a lower connection 202 that connects the packer setting tool 200 to a connection pipe 214 downhole of the packer setting tool 200. The packer setting tool 200 includes a flow through pipe 210 that provides a fluid passage 212 between the inner string (160, FIG. 1) and the surface. The packer setting tool 200 includes a connection device 260 that may include a number of spaced connection members, such as fingers 262a, 262b, etc., each such finger having a connection end, such as dogs 264a, 264b, which connect to or engage with a packer member 281. Spacing between adjacent fingers may be utilized to run the communication link 184, FIG. 1 as described later. The packer setting tool 200 further includes a device 270 that enables the packer setting tool 200 to disengage from the packer 280 after the packer has been set. The packer setting tool 200 further includes a piston 230 outside the flow through pipe 210 and a shroud 222 over the piston 230. The packer setting tool 200 also includes a movable outer sleeve 220 coupled to the piston 230. Packer 280 further includes a movable packer setting member 284, which member when moved causes the packer setting elements 282 to extend and engage with the casing (104, FIG. 1). To set the packer 280 against the casing, fluid under pressure is supplied to the piston 230, which moves the piston 230 downhole (to the right in FIG. 2). The piston 230 moves the outer sleeve 220 to the right, which moves the packer setting member 284 to the right to set the packer elements 282 against the casing (104, FIG. 1). In one aspect, the communication link 184 may be routed or placed under the shroud 222 and over the piston and over a part of the outer sleeve 220, as shown by label 290a The communication link 184 is then run through a bore 221 in the outer sleeve 220 as shown by label 290b and then between fingers 262a, 262b as shown by label 290c and then outside 214a of the connection pipe 214 and below the packer 280, as shown by label 290c. The communication link 184 then continues to run along the outside of the tubing 158, as shown by label 290d. The communication link 184 may be secured to the tubing 158 by any suitable mechanism, including but not limited to, clamps. Routing the communication link 184 through the outer sleeve 220 and the connection device 260 of the packer setting tool 200 and then between the ID of the packer 280 and the inner string as described herein enables the communication link 184 to pass from a location above the packer setting tool 200 to a location below the packer setting tool 200 without being exposed to high velocity frac slurry.
FIG. 3 shows certain details of an exemplary cross-over tool 300 with the routing of the communication link 184 therethrough, according to one non-limiting embodiment of the disclosure. The cross-over tool 300 has an upper connection 301 that connects the cross-over tool to the pipe 158 and a lower connection 302 that connects the cross-over tool to a section 303 of the service tool 150 below the cross-over tool 300. The cross-over tool 300 includes a cross-over assembly 310 for supplying a treatment fluid 352 to a production zone, as described in reference to FIG. 1. The treatment fluid 352 may be any suitable fluid for performing a treatment operation, including, but not limited to, a mixture of water or gel and a proppant, such as sand or manufactured proppants. In one non-limiting embodiment, the cross-over assembly 310 includes a housing 320 that includes a number of through holes 322a, 322b, etc., along the length of the body 320. The body 320 further includes a number of radially spaced fluid inlets 324a, 324b, etc. (hidden in FIG. 3 but depicted in FIG. 4), etc. around the body 320. The body 320 further includes inserts 330a, 330b, etc. over the fluid inlets 324a, 324b, respectively, as shown in more detail in reference to FIG. 4. Each such insert includes a number of ports or fluid passages, such as ports 340a in insert 330a, ports 340b in insert 330b, etc. for supplying the treatment fluid 152 to the production zones, such as zones Z1-Zn shown on FIG. 1. Although the cross-over tool is shown to contain a number of elements, in aspects, it may only contain a frac port or another configuration know in the art.
FIG. 4 shows a section 400 of the cross-over assembly 310 shown in FIG. 3. The section 400 includes the housing 320 with through holes 322a, 322b, 322c and 322d drilled through the housing 320. The section 400 includes a number of fluid inlets 324a, 324b, etc., wherein inlet 324a is configured to be covered by insert 330a, inlet 324b by 333b, etc., and wherein insert 330a includes ports 340a and insert 330b includes ports 340b, etc.
Referring to FIGS. 3 and 4, in one aspect, the communication link 184 may be run through one or more holes, such as through holes 322a, 332b, etc. of the cross-over assembly 310. FIG. 3 shows communication link 184 running or passing through hole 322a from above the cross-over tool to below the cross-over tool. During a fracing operation, the treatment fluid 158, which can be extremely abrasive due to the high velocity and presence of proppant and other chemicals, such as acids, passes through the ports 340a, 340b, etc. under high pressure and can damage control lines, such as communication link 184. Routing the communication link 184 through passages 322a, 322b, prevents the communication link from coming in direct contact with the flow of the treatment fluid 352 through the cross-over tool 300.
FIG. 5 shows placement of exemplary sensors in system 100 for determining various parameters of interest during a treatment operation. The parameters of interest may include, but, are not limited to, weight or load on a device in the inner string 160, tension on a device in the inner string 160, a location in the inner string or the outer string, location temperature at one or more locations and/or a temperature profile, pressures at one or more locations and/or a pressure profile, micro-seismic signals produced by the flow of a treatment fluid into the formation and/or cracking of the formation during a fracing operation, one or more flow rates of the fluid, and opening or closing of a device, such a sleeve valve. In one non-limiting embodiment, the system 100 may include on the inner string one or more weight and tension sensors 510, one or more pressure and temperature sensors P/T to determine the pressures and temperatures in the wellbore, one or more flow sensors 520 for determining the flow of a fluid, such as the flow of the treatment fluid 152 at one or more locations in the wellbore, and micro-seismic sensors 530, such acoustic sensors, for determining sound wave during a fracing operation to determine the effectiveness of the fracing operation. In another aspect, tags 544a, 544b, etc., such as magnetic tags, may be placed spaced apart on or proximate to a moving member, such as a sleeve of a sliding sleeve valve 140a for determining the movement of the sleeve and to ensure that the valve 140a has been correctly opened or closed. Tags, such as tags 544a, 544b also may be utilized to locate devices in the outer string 120 and/or to position a device, such as the set down tool 170, in the inner string 160 at a selected location inside the outer string 120. One or more tag detection sensors, such as sensors 545, may be placed in the inner string to detect the presence of the tags in the outer string 120. The tags may be of any suitable type, including, but not limited to, radiation tags, acoustic tags, electrical or resistive tags, and any other tags known in the art. Tags may also be utilized to locate other positions on the outer string 120 for any other purpose, including, but not limited to, use by the opening tool 162, closing tool 164, reverse valve 166 and the like. In another aspect, one or more suitable sensors, such as sensor 550 may be placed on the outside of the outer string 120 and a transmitter 552 may be placed on the inside of outer string 120. The sensor may include a battery for power and transmits signals to a receiver 554 in the inner string 160. Power to the control circuit 185 may be provided via a conductor in the communication link 184 by batteries 186 in the control circuit 185.
Still referring to FIG. 5, the sensors 520, 530, 544a, 544b, 550, etc. in the system 100 provide signals corresponding to their selected parameters of interest to the control circuit 185. In one aspect, the control circuit 185 may preprocess the received signals, such as pre-amplifying and digitizing the received signals, and transmit the digitized signals via the control line to a surface controller 590 (such as a computer or computer-based system) for further processing and for providing real-time information to the operator for taking actions as necessary. In another aspect, the control circuit 185 may include a processor, such as a microprocessor 586, a memory device 587, such as a solid state memory and programmed instruction 588 accessible to the processor 586 for executing instructions contained in the programs 588. The processor 586 may also be configured to receive signals from the surface controller 590, process the signals from the downhole sensors and transmit information as directed by the surface controller. Although the embodiment of FIG. 5 is described in reference to a wire-type links (which for example may include electric conductor(s) or a fiber optic link(s)) run in or along the inner string 160, other links, including acoustic links, may also be utilized for the purposes of this disclosure. For example, an acoustic link may include a transceiver 580 that receives signals from the control circuit 185 and transmits such signals via the inner string 160 to the surface. For long distances, repeaters 582a, 582b, 582c, etc., may be placed in the inner string 160 to receive, amplify, condition and retransmit the signals to the next repeater or the surface as the case may be. Thus, in one aspect, the disclosure provides real-time two-way communication between a surface location and one or more locations in a wellbore via the inner string 160.
The foregoing disclosure is directed to the certain exemplary embodiments and methods. Various modifications will be apparent to those skilled in the art. It is intended that all such modifications within the scope of the appended claims be embraced by the foregoing disclosure. The words “comprising” and “comprises” as used in the claims are to be interpreted to mean “including but not limited to”. Also, the abstract is not to be used to limit the scope of the claims.
Patent Application
20150167425
