Patent Application
20090223663
1. Field of the Invention
The present invention relates to systems, assemblies and processes for controlling equipment, tools and the like that are positioned in a subterranean well bore, and more particularly, to systems, assemblies and processes for controlling a plurality of equipment, tools and the like that are positioned in a subterranean well bore.
2. Description of Related Art
In the production of fluid from subterranean environs, a well bore is drilled so as to penetrate one or more subterranean zone(s), horizon(s) and/or formation(s). The well is typically completed by positioning casing which can be made up of tubular joints into the well bore and securing the casing therein by any suitable means, such as cement positioned between the casing and the walls of the well bore. Thereafter, the well is usually completed by conveying a perforating gun or other means of penetrating casing adjacent the zone(s), horizon(s) and/or formation(s) of interest and detonating explosive charges so as to perforate both the casing and the zone(s), horizon(s) and/or formation(s). In this manner, fluid communication is established between the zone(s), horizon(s) and/or formation(s) and the interior of the casing to permit the flow of fluid from the zone(s), horizon(s) and/or formation(s) into the well. The well is subsequently equipped with production tubing and convention associated equipment so as to produce fluid from the zone(s), horizon(s) and/or formation(s) of interest to the surface. The casing and/or tubing can also be used to inject fluid into the well to assist in production of fluid therefrom or into the zone(s), horizon(s) and/or formation(s) to assist in extracting fluid therefrom.
Often during the drilling and completion of a well or during production or injection of fluid from or into a well or subterranean environs, it can be desirable to control the operation of multiple tools, equipment, or the like, for example perforating guns, cutters, packers, valves, sleeves, etc., that can be positioned in a well. In the production of fluid from or injection of fluid into subterranean environs, multiple tools and equipment are often positioned and operated in a well bore. For example, a plurality of perforating guns can be deployed within a well bore to provide fluid communication between multiple zones, horizons and/or formations. Upon detonation, these guns file projectiles through casing cemented within the well bore to form perforations and establish fluid communication between the formation and the well bore. Often these perforating guns are detonated in sequence. A plurality of flapper valves can be used in conjunction with multiple perforating guns to isolate the zone, horizon or formation being completed from other zones, horizons and/or formations encountered by the well bore. As another example, packers can be deployed on a tubular and expanded into contact with casing to provide a fluid tight seal in the annulus defined between the tubular and the casing. Flow chokes can be used to produce the well from multiple zones with these chokes set at different openings to balance the pressure existing between multiple subterranean zones, horizons and/or formations so that a plurality of such zones, horizons and/or formations can be produced simultaneously.
Hydraulic systems have been used to control the operation of tools positioned in a well. Such systems have a control system and a down hole valve. The control system includes surface equipment, such as a hydraulic tank, pump, filtration, valves and instrumentation, control lines, clamps for the control lines, and one or more hydraulic controller units. The control lines run from the surface equipment to and through the wellhead and tubing hanger to desired equipment and tools in the well. These control lines are clamped usually along a tubular that is positioned within a well. The control lines can be connected to one or more hydraulic control units within a well for distributing hydraulic fluid to the down hole valves.
Several basic arrangements of hydraulic control lines are used in a well. In a direct hydraulic arrangement, each tool that is to be controlled will have two dedicated hydraulic lines. The “open” line extends from the surface equipment to the tool and is used for transporting hydraulic fluid to the downhole control valve to operate the tool, while the “close” line extends from the tool to the surface equipment and provides a path for returning hydraulic fluid to the surface of the earth. The practical limit to the number of tools that can be controlled using the direct hydraulic arrangement is three, i.e. six separate hydraulic lines, due to the physical restraints in positioning hydraulic lines in a well. The tubing hanger through which the hydraulic lines run also has to accommodate lines for a gauge system, at least one safety valve and often a chemical injection line, which limits the number of hydraulic lines the hanger can accommodate. When it is desirable to control more than three tools in a well, a common close arrangement can be employed in which an open line is run to each tool to be controlled and a common close line is connected to each tool to return hydraulic fluid to the surface. Again, the common close system has a practical limit of controlling five tools, i.e. six separate hydraulic lines.
In another arrangement, a single hydraulic line is dedicated to each tool and is connected to each tool via a separate, dedicated controller for each tool. To open the tool, the hydraulic fluid in the dedicated line is pressurized to a first level. Thereafter, the hydraulic fluid in the dedicated line is pressurized to a higher level so as to close the tool. In a digital hydraulics system, two hydraulic lines are run from the surface equipment to a downhole controller that is connected to each of the tools to be controlled. Each controller is programmed to operate upon receiving a distinct sequence of pressure pulses received through these two hydraulic lines. Each tool has another hydraulic line is connected thereto as a common return for hydraulic fluid to the surface. The controllers employed in the single line and the digital hydraulics arrangements are complex devices incorporating numerous elastomeric seals and springs which are subject to failure. In addition, these controllers use small, inline filters to remove particles from the hydraulic fluid that might otherwise contaminate the controllers. These filters are prone to clogging and collapsing. Further, the complex nature of the pressure sequences requires a computer operated pump and valve manifold which is expensive.
In accordance with the “distribution hub” arrangement, two hydraulic lines are run from the surface to one downhole controller to which each tool to be controlled is connected by its own set of two hydraulic lines. This controller can be ratcheted to any of a number of predetermined locations, each of which connects the control lines of a given tool to the control lines running from the surface to the controller. In this manner, each tool can be operated independently from the surface. By ratcheting the controller to another location, another tool can be operated. This arrangement is expensive due to the large number of components and complex arrangement of seals in the controller and unreliable as it is difficult to get feedback to the surface on the exact position of the controller, especially if the operator has lost track of the pulses previously applied. Thus, a need exists for hydraulic control systems, assemblies and processes for use in controlling multiple tools in a well which is relatively inexpensive, simple in construction and operation and reliable.
To achieve the foregoing and other objects, and in accordance with the purposes of the present invention, as embodied and broadly described herein, one characterization of the present invention is a hydraulic control system for use in a subterranean well is provided. The control system comprises a control line positioned in a subterranean well and extending adjacent at least one tool positioned within the subterranean well. The control line is sized to permit passage of a control device and each of the at least one tool has a reader device connected thereto.
In another characterization of the present invention, a process is provided for conveying at least one control device capable of generating one or more unique signals through a control line positioned in a subterranean well so as to control the operation of at least one tool positioned in the well outside of the control line.
In yet another characterization of the present invention, a process is provided for conveying hydraulic fluid via a first hydraulic line to at least one tool positioned in a subterranean well to control the operation of the tool. At least one control device is conveyed through a control line positioned in the well and outside of the first hydraulic line and the at least one tool. Each of the at least one control device is capable of generating one or more unique signals for controlling flow of hydraulic fluid from the first hydraulic line to the at least one tool.
The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present invention and, together with the description, serve to explain the principles of the invention.
In the drawings:
As utilized throughout this description, the term “signal control line” refers to a continuous or jointed line, conduit, tubular or similar structure for conveying fluid and a control device. The substantially axial bore through the control line is sufficient to permit passage of a control device therethrough but the outside diameter of the control line is sufficiently small so as not to impede placement of other lines, tubulars, tools and equipment within the well. A nonlimiting example of suitable diameters for a signal control line are an outside diameter of from about 0.25 inch to about 0.50 inch and a substantially axial bore diameter of from about 0.15 inch to about 0.40 inch. The diameter of the substantially axial bore through the signal control line used in accordance with the present invention is not sufficient to allow commercial quantities of formation fluids to be produced therethrough. The signal control line can be constructed of any suitable material, for example stainless steel or a stainless steel alloy. A “signal device” refers to a device which is capable of generating one or more unique signals. Nonlimiting examples of a signal device are a radio frequency identification device (RFID), a device carrying a magnetic bar code, a radioactive device, an acoustic device, a surface acoustic wave (SAW) device, a low frequency magnetic transmitter and any other device that is capable of generating one or more unique signals. The signal device can have any suitable peripheral configuration and geometric shape, and is sized to permit conveyance through the signal control line. Some signal devices, for example RFID, can require a peripheral configuration and geometric shape to inhibit tumbling of the RFID during conveyance through the signal control line. A suitable RFID is commercially available from Sokymat SA, Switzerland under the trade name “Glass Tag 8 mm Q5”. A “reader device” refers to a device capable of transmitting signals to and receiving signals from a signal device.
In accordance with one embodiment of the present invention as illustrated in
In operation, a suitable signal device 12 can be conveyed from the well head 10 through line 14, for example in suitable fluid, such as hydraulic oil or water, that can be pumped by equipment located at the surface. The signal device 12 is sized and configured to inhibit the signal device from tumbling in line 14 during conveyance (
Each reader device 20 can be programmed to respond to its own unique signal or the same signal of at least one other reader device. As the signal device 12 is conveyed through line 14, the unique signal transmitted thereby can be received and read by each successive reader device. If the unique signal matches that programmed in the reader device, the reader device transmits a control signal to actuate the associated tool 30. Ultimately, the signal device 12 exits through the end of the control line 14 into the well. Thereafter, one or more additional control devices can be conveyed via control line 14 to actuate one or more tools 30 in any sequence and manner desired. In this manner, an unlimited number of tools can be actuated by conveying one or more control devices via control line 14. When line 14 is open at end 18 to the well bore, it is subject to hydrostatic fluid, and as such, the hydraulic pressure exerted in this line must be sufficient to overcome this pressure so as to convey signal device 12 through line 14.
In accordance with another embodiment of the present invention as illustrated in
A plurality of tools or equipment 130A, 130B and 130N are positioned in a well and can have a piston or sleeve 132A, 132B and 132N, respectively, moveably secured therein. Each tool 130A, 130B and 130N can be connected to hydraulic line 156 by means of lines 134A, 134B and 134N, respectively, each of which has a corresponding valve 136A, 136B and 136N. Reader devices 120A, 120B and 120N are electrically connected to a suitable power source 124A, 124B, and 124N and antennas 122A, 122B and 122N, respectively. Nonlimiting examples of suitable power sources are batteries. These power sources can be preprogrammed to be in a sleep mode except for certain predetermined periods of time so as to conserve power consumption and therefore extend the life of the power source. As illustrated antennas 122A, 122B and 122N are coiled to surround control line 114 such that the orientation of the signal device 112 within control line 114 is immaterial. Each reader device 120A, 120B and 120N can be electrically connected to corresponding motors 126A, 126B and 126N, respectively, which in turn drive shaft or stem 127A, 127B and 127N to open or close valves 136A, 136B and 136N as will be evident to a skilled artisan. An unlimited number of tools 130 can be controlled by this embodiment of the present invention, with the total number of tools that are positioned in a well and capable of being controlled being designated by the letter “N”. Hydraulic fluid, such as hydraulic oil or water, can be used in each of the three hydraulic lines and can be pressurized by any suitable means, such as a pump located at or near the well head, to a pressure sufficient to overcome the hydrostatic pressure of fluid present in the well to move from the well head through fluid and signal device 112 a hydraulic line and into the well.
As typically positioned in a well, valves 136A, 136B and 136 N are in a closed positioned and pistons 132A, 132B and 132N are positioned to one end of the respective tool 130 as noted by the positions x or y in
In operation, a suitable signal device 112 can be conveyed from the well head 110 through line 114, for example in fluid pumped by equipment located at the surface. Each signal device 112 is programmed to generate a unique signal. Similarly, each reader device 120A, 120B and 120N is programmed to look for a unique code signal. As the signal device 112 passes in proximity to a given reader device 120, the unique signal transmitted by signal device 112 can be received by an antenna 122. If a given reader device 120 is programmed to respond to the signal transmitted by the device 112 via the associated antenna 122, the reader device 120 transmits a corresponding control signal to the associated motor 126 which in turn causes valve 136 to open via shaft 127. Reader devices 120 can also transmit signals which in turn are received by and cause signal device 112 to generate the unique signal. As hydraulic fluid in line 154 is thereby permitted to flow through line 134 and valve 136, the pressure of the hydraulic fluid causes piston 132 in tool 130 to move to the desired position and thereby actuate the tool. Movement of the piston 132 in tool 130 causes the hydraulic fluid on the other side of piston 132 to flow back to the well head 110 via hydraulic line 164. To move piston 132 to a different position, pressure on the hydraulic fluid in line 154 or line 164 can be increased to move the piston with the associated mechanism, such as a collet, thereby permitting the piston to sequentially achieve several positions along the tool 130.
Each reader device 120 can be programmed to respond to its own unique signal or the same signal of at least one other reader device. As the signal device 112 is conveyed through line 114, the unique signal transmitted thereby can be received and read by each successive reader device. If the unique signal matches that programmed in the reader device, the reader device transmits a control signal to open the associated motor 126 and valve 136. Ultimately, the signal device 112 exits through the end of the control line 114 into the well. Thereafter, one or more additional motor(s) 126 and valve(s) 136 in any sequence and manner desired. In this manner, an unlimited number of tools 130 can be actuated by conveying one or more control devices via control line 114. As line 114 is open at end 118 to the well bore, it is subject to hydrostatic fluid and as such the hydraulic pressure exerted in this line must be sufficient to overcome this pressure so as to convey signal device 112. Alternatively, line 114 can be connected to line 158 thereby permitting passage of signal device 112 to the surface. Signal device 112 can be configured to receive a signal from a given reader device that the unique signal conveyed by the signal device was received by the reader device. In this instance, the reader devices 120 are transceivers permitting each device to receive a unique signal from the signal device and to transmit another unique signal back to the signal device. Each signal device 112 can also be equipped with suitable gauges to measure well, formation, and/or fluid conditions which can then be recorded in signal device 112. Nonlimiting examples of suitable gauges are temperature and pressure gauges. Information contained in the signal device 112 can be read at the surface, erased from the signal device 112, if desired, and the signal device can be programmed to emit another unique signal for use in the same well or another well.
To close each valve 136, each associated reader device can be preprogrammed to actuate the appropriate motor 126 and shaft 127 after a period of time to close the associated valve 136. Alternatively, a signal device 112 can be conveyed via line 114 to transmit a unique signal to the appropriate reader device 120 via antenna 122 which in turn transmits a corresponding control signal to the associated motor 126 causing shaft 127 to close valve 136.
In accordance with another embodiment of the present invention as illustrated in
In the embodiment of the present invention illustrated in
In the embodiment of the present invention illustrated in
Change-over valves 336 are positioned in hydraulic lines 334 and are connected to and controlled by motors 326 and shafts 327. Reader devices 320A, 320B and 320N are electrically connected to a suitable power source 324A, 324B, and 324N and antennas 322A, 322B and 322N, respectively. Nonlimiting examples of suitable power sources are batteries. These power sources can be preprogrammed to be in a sleep mode except for certain predetermined periods of time so as to conserve power consumption and therefore extend the life of the power source. As illustrated, antennas 322A, 322B and 322N are coiled to surround control line 314 such that the orientation of the signal device 312 within control line 314 is immaterial. Each reader device 320A, 320B and 320N is electrically connected to corresponding motors 326A, 326B and 326N, respectively, which in turn drive shaft or stem 327A, 327B and 327N to open or close valves 336A, 336B and 336N as will be evident to a skilled artisan.
Another reader device 380 is electrically connected to a suitable power source 384 and antenna 382 which is configured to surround hydraulic line 314. Reader device 380 is also electrically connected to motors 396 which drives shaft or stem 397 to open or close valve 390 as will be evident to a skilled artisan.
In operation, a signal device 312 can be conveyed via line 314, through open valve 390 and open end 318 into the well for example in fluid pumped by equipment located at the surface. Each signal device 312 is programmed to generate a unique signal. Similarly, each reader device 320A, 320B and 320N is programmed to look for a unique code signal. As the signal device 312 passes in proximity to a given reader device 320, the unique signal transmitted by signal device 312 can be received by an antenna 322. If a given reader device 320 is programmed to respond to the signal transmitted by the device 312 via the associated antenna 322, the reader device 320 transmits a corresponding control signal to the associated motor 326 which in turn causes valve 336 to open via shaft 327. Reader devices 320 can also transmit signals which in turn are received by and cause signal device 312 to generate the unique signal. Antenna 382 conveys a signal received from signal device 312 to actuate motor 396 and shaft 397 to close valve 390. Thereafter, hydraulic fluid in line 314 is thereby permitted to flow through line 334 and valve 336 thereby causing piston 332 in tool 330 to move to the desired position and thereby actuate the tool. Hydraulic fluid flowing around a given piston 332 is permitted to flow back into the well via hydraulic line 338. Reader device 380 can be programmed to cause valve 390 to open a predetermined time after being closed or the unique signal from signal device 312 can contain instructions to cause the reader device to open valve 390 in a predetermined amount of time.
The following example demonstrates the practice and utility of the present invention, but is not to be construed as limiting the scope thereof.
A well is drilled to total depth (TD) so as to penetrate a subterranean formation of interest and the drilling assembly is removed from the well. A 7 inch outer diameter intermediate casing is positioned in the well to extend substantially from the surface of the earth to a point above the subterranean formation of interest. The intermediate casing is cemented to the well bore by circulating cement. Excess cement is drilled from the intermediate casing and well bore extending below the intermediate casing through the subterranean zone of interest.
A 3.5 inch outer diameter production casing is equipped with 6 sliding sleeves and has 3 hydraulic lines attached to the outside of the production casing. The sliding sleeves are arranged in series and referred to hereafter as sliding sleeves 1-6, with sliding sleeve 1 being proximal and sliding sleeve 6 being distal the intermediate casing. The hydraulic lines are a control line, a hydraulic power open line and a hydraulic power close line. The end of the production casing has a cementing shoe and a check valve assembly. The production casing and associated equipment and lines is lowered into the well until all sleeves which are in the closed position are in the open hole (portion of the well without intermediate casing).
Water-based, cross-linked fluids are pumped down the production casing and placed in annulus between the production casing and the open hole from TD to above sliding sleeve 1. The fluids are displaced with wiper plug that is conveyed through the production casing and latches in place at the bottom thereof so as to prevent flow of well fluids into the production casing. The fluids are allowed to thicken and create zonal isolation barriers.
A radio frequency identification device (RFID) encoded with specific code is pumped down the control line to actuate the shuttle valve in distal sliding sleeve from the intermediate casing (sleeve 6). Actuation is achieved by means of a radio frequency transceiver associated with the sliding sleeve. Approximately 7 gallons of hydraulic fluid are required to pump the RFID through the control line and into the well. Approximately 3,000 psi pressure is applied via hydraulic fluid in the power open line to open sliding sleeve 6. No pressure should be applied to the power close line so that minor fluid returns can occur as the piston in the sliding sleeve moves positions. After some time period, the shuttle valve in sliding sleeve 6 should close, locking the sleeve in the open position. Thereafter, approximately 3,000 barrels of fluid are pumped through the production casing, open sleeve 6 and into the formation adjacent sliding sleeve 6 so as to fracture and stimulate production of fluids from this adjoining formation. Sand can be incorporated into the stimulation fluid if desired.
Another RFID chip encoded with a specific code down is pumped down control line to actuate the shuttle valve in sliding sleeve 6. Approximately 3,000 psi pressure is applied via hydraulic fluid in the power close line to close sliding sleeve 6. No pressure should be applied to the power open line so that minor fluid returns can occur as the piston in the sliding sleeve moves positions. After some time period the shuttle valve in sliding sleeve 6 should close, locking the sleeve in the closed position. Thereafter, the production casing is pressure tested to confirm integrity. A RFID encoded with a specific code is pumped down the control line to actuate the shuttle valve in sliding sleeve 5. Approximately 3,000 psi pressure is applied to the hydraulic fluid in power open line to open sliding sleeve 5. No pressure should be applied to the power close line so that minor fluid returns can occur as the piston in the sliding sleeve moves positions. After some time period the shuttle valve in sliding sleeve 5 should close, locking the sleeve in the open position.
Thereafter, approximately 3,000 barrels of fluid are pumped through the production casing, open sleeve 5 and into the formation adjacent sliding sleeve 5 so as to fracture and stimulate production of fluids from this adjoining formation. Sand can be incorporated into the stimulation fluid if desired.
Another RFID chip encoded with a specific code down is pumped down control line to actuate the shuttle valve in sliding sleeve 5. Approximately 3,000 psi pressure is applied via hydraulic fluid in the power close line to close sliding sleeve 5. No pressure should be applied to the power open line so that minor fluid returns can occur as the piston in the sliding sleeve moves positions. After some time period the shuttle valve in sliding sleeve 5 should close, locking the sleeve in the closed position. Thereafter, the production casing is pressure tested to confirm integrity. This process is repeated for sliding sleeves 4, 3, 2, and 1 respectively.
After the formation adjacent each of sleeves 1-6 has been stimulated, the cross-linked fluids are permitted to break down thereby removing the isolation barriers. Separate RFIDs are pumped down the control line to open and allow the well to be flow tested sequentially open sleeves 1, 2, 3, 4, 5, and 6 in order, while applying pressure to power open line and holding no back pressure on the power close line. The production casing and associated sleeves and lines can then be retrieved from the well, after circulating fluid down the production casing and up annulus. Thereafter, the well completion operations are continued.
Although the antennae of the present invention has been illustrated in
While the foregoing preferred embodiments of the invention have been described and shown, it is understood that the alternatives and modifications, such as those suggested and others, can be made thereto and fall within the scope of the invention.
