WO2010024818A1

WO2010024818A1 - Bypass of damaged lines in subterranean wells

Info

Publication number: WO2010024818A1
Application number: PCT/US2008/074744
Authority: WO
Inventors: Mitchell C. Smithson; Brett W. Bouldin
Original assignee: Welldynamics, Inc.
Priority date: 2008-08-29
Filing date: 2008-08-29
Publication date: 2010-03-04

Abstract

Bypassing damaged lines in a well. A subterranean well system includes a circuit extending in the well to a well tool. A set of multiple redundant lines is provided at a location along the circuit. Each of the set of lines is capable of providing conductivity between portions of the circuit. A method of providing conductivity across a damaged portion of a circuit in a subterranean well includes the steps of : damaging at least one line of a set of redundant lines extending along a tubular string; and isolating the damaged at least one line from an undamaged portion of the circuit.

Description

BYPASS OF DAMAGED LINES IN SUBTERRANEAN WELLS

TECHNICAL FIELD The present disclosure relates generally to equipment utilized and operations performed in conjunction with a subterranean well and, in an embodiment described herein, more particularly provides for bypassing damaged lines in a well.

BACKGROUND

Various types of lines are sometimes installed in subterranean wells. For example, the lines could be electrical, optical, hydraulic, or other types of lines, and could be for monitoring of well conditions, injecting or withdrawing fluid, or for command or control of various types of well tools. The well tools could be flow control devices (such as valves, chokes, etc.), various types of sensors, packers, plugs, etc., and if optical fiber is used as a line, the line itself could comprise a temperature sensing well tool (e.g., in distributed temperature sensing, etc.) or a pressure sensing well tool (e.g., in interferometric pressure sensing, etc.). Unfortunately, a wellbore is a hostile environment for lines, and it is not uncommon for lines to become damaged at various points in the life of a well. For example, a line can become damaged prior to, during or after installation of the line in the well, and a line can become damaged during certain operations in the well, such as, when a window opening is cut through a sidewall of a casing or liner string in the process of drilling a branch wellbore from a parent wellbore. In the past, typical attempts to prevent such line damage during branch wellbore drilling have tried to cut the window at a position away from the line. These attempts require either orienting the line and window at known positions relative to the wellbore (e.g., with the line oriented vertically downward and the window oriented vertically upward relative to the wellbore, thereby requiring precise rotational orienting of a window joint in the wellbore), or orienting the window and line at known positions relative to the window joint (e.g., with the line and window oriented relative to an orienting device of the window joint, or by detecting the line's azimuthal position after installation of the casing string) .

Each of these prior methods has certain disadvantages. For example, precise rotational orienting of a window joint relative to a wellbore requires use of instruments such as gyroscopes or MWD tools (use of which are time-consuming and expensive), and precise rotation of the window joint from perhaps thousands of meters away. Use of an orienting device of the window joint requires that the window joint be specially constructed (instead of the window joint being simply a joint of standard casing or liner) and, unless the window joint is rotationally oriented relative to the wellbore as discussed above, does not necessarily allow the window to be formed in an optimal direction relative to the parent wellbore.

Therefore, it may be seen that improvements are needed in the art of utilizing lines which may be damaged in wellbores.

SUMMARY

In carrying out the principles of the present disclosure, systems and methods are provided which solve at least one problem in the art. One example is described below in which a set of redundant lines extend across a location where at least one of the lines may be damaged. Another example is described below in which a damaged line is isolated from the remainder of a circuit, thereby allowing the other redundant line(s) to provide conductivity between portions of the circuit.

In one aspect, a subterranean well system is provided. The system includes a circuit extending in the well to a well tool. A set of multiple redundant lines is provided at a location along the circuit. Each of the set of lines is capable of providing conductivity between different portions of the circuit.

In another aspect, a method of providing conductivity across a damaged portion of a circuit in a subterranean well is provided. The method includes the steps of: damaging at least one line of a set of redundant lines extending along a tubular string; and isolating the damaged at least one line from an undamaged portion of the circuit.

These and other features, advantages, benefits and objects will become apparent to one of ordinary skill in the art upon careful consideration of the detailed description - A -

of representative embodiments of the disclosure hereinbelow and the accompanying drawings, in which similar elements are indicated in the various figures using the same reference numbers .

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a well system and method embodying principles of the present disclosure;

FIG. 2 is schematic cross-sectional view of a portion of a tubular string in the system of FIG. 1;

FIG. 3 is a schematic view of an electrical or optical bypass arrangement which may be used in the system;

FIG. 4 is a schematic view of a hydraulic bypass arrangement which may be used in the system; FIGS. 5A & B are schematic views of a magnetically actuated valve which may be used in the hydraulic bypass arrangement;

FIG. 6 is a schematic view of a magnetically actuated switch which may be used in the electrical bypass arrangement;

FIGS. 7A & B are schematic views of the system and method, wherein the magnetically actuated valves and/or switches are selectively actuated;

FIG. 8 is a schematic view of the system and method, wherein a tubular string inserted through a window has a line which is connected to a bypass arrangement associated with the window;

FIG. 9 is a schematic view of a mechanically actuated bypass arrangement; FIGS. 1OA & B are enlarged scale schematic views of a portion of the mechanically actuated bypass arrangement, prior to and after severing of a line thereof;

FIG. 11 is a schematic cross-sectional view of the mechanically actuated bypass arrangement;

FIG. 12 is a schematic view of another configuration of the mechanically actuated bypass arrangement;

FIG. 13 is a schematic view of another electrical bypass arrangement; FIG. 14 is a schematic view of a combined electrical and hydraulic bypass arrangement; and

FIG. 15 is a schematic view of another combined electrical and hydraulic bypass arrangement.

DETAILED DESCRIPTION

It is to be understood that the various embodiments of the present disclosure described herein may be utilized in various orientations, such as inclined, inverted, horizontal, vertical, etc., and in various configurations, without departing from the principles of the present disclosure. The embodiments are described merely as examples of useful applications of the principles of the disclosure, which is not limited to any specific details of these embodiments . In the following description of the representative embodiments of the disclosure, directional terms, such as "above", "below", "upper", "lower", etc., are used for convenience in referring to the accompanying drawings. In general, "above", "upper", "upward" and similar terms refer to a direction toward the earth's surface along a wellbore, and "below", "lower", "downward" and similar terms refer to a direction away from the earth's surface along the wellbore.

Representatively illustrated in FIG. 1 is a well system 10 and associated method which embody principles of the present disclosure. In the well system 10, a parent wellbore 12 has been drilled, and a tubular string 14 (such as a casing or liner string) has been sealed and secured in the wellbore with cement 16. It is now desired to drill a lateral or branch wellbore 18 extending outwardly from the parent wellbore 12.

However, a circuit 20 comprising various lines extends longitudinally along the tubular string 14, and the act of drilling the branch wellbore 18 can possibly damage a line 22a of the circuit which extends across a window joint 24 of the tubular string 14. Thus, when a mill, drill or other cutting tool 26 cuts through a sidewall of the tubular string 14 to form a window opening 28 for drilling the branch wellbore 18, the line 22a can be severed (as depicted in FIG. 1), or otherwise damaged.

The circuit 20 extends between a remote location (such as a control system 30 at the earth's surface or a subsea location) and one or more well tools 32. A portion 20a of the circuit 20 extends on one side of the window joint 24, and another portion 20b of the circuit extends on an opposite side of the window joint. Unless the principles of this disclosure are used, the damage to the line 22a could possibly prevent conductivity between the portions 20a,b of the circuit 20 and thereby prevent proper operation, monitoring, control, etc. of the well tool 32 from the remote location. Note that the circuit 20 can comprise any number and type of lines. These lines can include any combination of electrical, optical and/or hydraulic or other types of lines. In addition, the well tool 32 may be any type or combination of well tools, such as flow control devices, sensors, etc. The circuit 20 may be connected to any number of well tools, and any number of circuits may be used to operate, monitor, control, etc., the well tool(s).

As depicted in FIG. 1, the parent wellbore 12 and tubular string 14 are generally horizontal, the branch wellbore 18 is drilled in an upward direction from the parent wellbore, and the portions 20a,b of the circuit 20 are exposed to (or in) the cement 16 between the tubular string and the wellbore 12. However, it should be clearly understood that these and other details of the well system 10 are merely used to illustrate one example of a useful application of the principles of this disclosure.

In other examples, the wellbores 12, 18 could be otherwise oriented, the circuit portions 20a, b could be internal to or within a sidewall of the tubular string 14, the tubular string may not be cemented in the wellbore 12, the line 22a could be damaged by an operation other than drilling of a branch wellbore, etc. Thus, it will be appreciated that the well system 10 and its associated method as described herein are not to be taken as limiting the principles of this disclosure in any manner.

In one unique feature of the well system 10 as depicted in FIG. 1, the line 22a is only one of a set 22 of redundant lines which extend longitudinally along the window joint 24. Another line 22b of the set 22 is illustrated in FIG. 1. Note that, although the line 22a has been damaged by the cutting tool 26, the other line 22b still provides conductivity between the portions 20a,b of the circuit 20.

Any number and combination of lines may be used in the set 22 of redundant lines. In the further examples described below, at least three redundant lines 22a-c are used, and the lines are preferably equally circumferentially spaced (e.g., spaced apart by 120 degrees) about the window joint 24. However, other numbers, spacings, positioning, orientations, etc. of the lines may be used in keeping with the principles of this disclosure.

Note that the damage to the line 22a as depicted in FIG. 1 is bypassed by the line 22b, but the damage can nevertheless detrimentally affect operation of the circuit 20. For example, if the line 22a is an electrical line the damage may result in detrimental shorting and/or grounding of the circuit 20, and if the line is a hydraulic line the damage may result in loss of fluid and/or pressure control in the circuit.

For at least these reasons and/or others, the well system 10 preferably includes provisions for isolating the damaged line 22a from the portions 20a, b of the circuit 20 which remain undamaged. Several examples of how such isolation may be accomplished are described below.

Note that, in the system 10, a particular orientation of the lines 22a, b and the window opening 28 relative to each other, or relative to the wellbore 12, is not required. For example, the window joint 24 can be in any azimuthal orientation relative to the parent wellbore 12, the branch wellbore 18 can be drilled in any direction outward from the parent wellbore, and the lines 22a, b can be azimuthally oriented in any direction relative to the window joint. These variations in orientation and direction may cause different ones of the lines 22a, b to be damaged when the branch wellbore 18 is drilled, but as long as at least one of the set 22 of lines remains undamaged (and thereby capable of bypassing the damaged lines), conductivity can still be provided between the portions 20a,b of the circuit 20. Thus, in another unique feature of the well system 10, the window joint 24 is not necessarily a specially constructed portion of the tubular string 14 (i.e., with orienting device(s) and precise relative positions for the window opening 28 and circuit 20, etc.).

Instead, the window joint 24 can be simply a joint of the same tubular material used in the tubular string 24 above and below the window joint, thereby significantly reducing the cost and logistical problems of providing the window joint. Of course, the window joint 24 could be specially constructed (e.g., including orienting devices, etc.), if desired.

Referring additionally now to FIG. 2, a cross-sectional view of the window joint 24 and set 22 of lines is representatively illustrated, taken along line 2-2 of FIG. 1. In this view, a preferred arrangement of the lines 22a-c relative to the window joint 24 may be clearly seen.

Specifically, the lines 22a-c are equally circumferentially spaced apart about the window joint 24, with the spacing being preferably approximately 120 degrees. If two lines were to be used in the set 22 the spacing could be 180 degrees, if four lines were to be used in the set the spacing could be 90 degrees, etc. In this manner, not all of the lines 22a-c will be damaged when the opening 28 is cut through the sidewall of the tubular string 14. Instead, at least one undamaged line will remain to bypass any damaged line(s) and thereby provide conductivity between the undamaged portions 20a,b of the circuit 20.

Although the lines 22a-c are depicted in FIG. 2 as being external to the window joint 24, the lines could instead be internal to the window joint or within the sidewall of the window joint. In addition, it should be understood that the principles of the invention are not limited to use of the circuit 20 and lines 22a-c therein with a window joint 24 or any particular operation in a well. Lines can become damaged in operations other than drilling of a branch wellbore (such as, installation of a tubular string, setting of a packer or hanger, acidizing, fracturing or gravel packing, etc.), and the principles of this disclosure may be used in conjunction with any of those other operations.

Referring additionally now to FIG. 3, a schematic view of the circuit 20 apart from the remainder of the system 10 is representatively illustrated. In this schematic view, the manner in which the damaged line 22a may be isolated from the undamaged portions of the circuit 20 can be seen.

As depicted in FIG. 3, a control module 34a is interconnected between the circuit portion 20a and the lines 22a-c, and another control module 34b is interconnected between the lines and the circuit portion 20b. The control module 34a includes switches 36a-c for selectively controlling conductivity between the circuit portion 20a and respective ones of the line 22a-c, and the control module 34b includes switches 36d-f for selectively controlling conductivity between the circuit portion 20b and respective ones of the lines 22a-c.

The switches 36a-f may be any type of selective conductivity control devices. For example, if the circuit 20 comprises an electrical circuit, then the switches 36a-f may be make-or-break switches, transistors, etc. If the circuit 20 comprises an optical circuit, then the switches 36a-f may be optical switches, etc. As depicted in FIG. 3, switches 36a and 36d are open, thereby isolating the damaged line 22a from the portions 20a, b of the circuit 20. The switches 36b,c,e,f are closed, thereby providing for conductivity between the portions 20a, b of the circuit 20 via the lines 22b, c. If, however, the line 22b were to become damaged, then switches 36b, e could be opened to isolate that line, and if the line 22c were to become damaged, then switches 36c, f could be opened to isolate that line.

Although in FIG. 3 both of lines 22b, c are used to bypass the damaged line 22a, only one such bypass line may be needed to provide conductivity between the circuit portions 20a,b. Nevertheless, the use of multiple bypass lines may be desirable in some circumstances.

Various examples of configurations and operation of the control modules 34a, b are described below. These examples provide variously for automatic isolation of the damaged line(s) upon such damage, and/or for isolation of the damaged line(s) prior to such damage.

Referring additionally now to FIG. 4, a schematic view of the circuit 20 is representatively illustrated apart from the remainder of the system 10. This view is similar in many respects to the view of FIG. 3, but differs in that the circuit 20 comprises a hydraulic circuit.

Instead of the switches 36a-f, the control modules 34a, b in the example of FIG. 4 include valves 38a-f. The valves 38a-f are illustrated as pilot-operated shuttle valves, but any type or combination of valves may be used, as desired.

The damaged line 22a is isolated from the undamaged portions 20a, b of the circuit 20 by the valves 38a, d. This prevents loss of fluid and pressure control due to the damaged line 22a. The valves 38b,c,e,f remain open, allowing the undamaged lines 22b, c to provide conductivity between the circuit portions 20a,b.

Referring additionally now to FIGS. 5A & B, a magnetically-operated valve 38 is representatively illustrated. The valve 38 may be used for any of the valves 38a-f described above. In particular, the valve 38 may be used in an example of the well system 10 which is configured to provide for isolating a line prior to the line becoming damaged, as described more fully below.

The valve 38 as depicted in FIG. 5A includes a body 40 and an operator member 42. For example, the valve body 40 could comprise a ball valve, and the operator member 42 could be a lever for rotating a ball of the valve to selectively open and close the valve. In this example, the valve 38 could be similar in many respects to a conventional ball valve.

However, as depicted in FIG. 5B, a permanent magnet 44 is attached to the operator member 42. When another magnet 46 having oppositely oriented polarity is positioned sufficiently close to the magnet 44, a resulting repulsive magnetic force Fr can rotate the member 42 in one direction, and when another magnet 48 having complementarily oriented polarity is positioned sufficiently close to the magnet 44, a resulting attractive magnetic force Fa can rotate the member in an opposite direction. Thus, the valve 38 can be selectively opened and closed by positioning selected ones of the magnets 46, 48 in close proximity to the magnet 44.

Although the valve 38 is described above as being similar in many respects to a ball valve, it should be understood that other types of valves (e.g., shuttle valves, needle valves, magnetostrictive valves, etc.) may be used if desired.

Referring additionally now to FIG. 6, a magnetically- operated switch 36 is representatively illustrated. The switch 36 may be used for any of the switches 36a-f described above. In particular, the switch 36 may be used in an example of the well system 10 which is configured to provide for isolating a line prior to the line becoming damaged, as described more fully below. As depicted in FIG. 6, the switch 36 includes the permanent magnet 44 and a conventional reed switch 50. The magnet 44 normally causes the reed switch 50 to close, but when the magnet 46 having opposing polarity is positioned in sufficiently close proximity, the magnetic field exerted on the reed switch is significantly diminished, and the switch opens. Thus, the switch 36 can be selectively opened and closed by selectively positioning or not positioning the magnet 46 in sufficiently close proximity.

The examples of FIGS. 5A & B and 6 utilize the magnetically-operated switch 36 and valve 38 on an exterior of the window joint 24, with the magnets 46, 48 on an interior of the window joint. In these examples, the window joint 24 is preferably made of a non-magnetically permeable material, such as aluminum or a composite material. However, if the components are otherwise positioned, then use of such non-magnetically permeable material in the window joint 24 may not be preferred. Referring additionally now to FIGS. 7A & B, an example of use of the magnetically-operated switch 36 and/or valve 38 in the well system 10 to isolate the line 22a prior to the line being damaged is schematically illustrated. In FIG. 7A, the window joint 24 and circuit 20 are illustrated apart from the remainder of the system 10, just prior to drilling the branch wellbore 18 through the sidewall of the window joint.

As depicted in FIG. 7A, the control modules 34a, b each include multiple magnetically-operated switches 36 and/or valves 38 for isolating a damaged one or more of the set 22 of lines. As a whipstock or deflector 52 is displaced through the window joint 24, appropriate ones of the switches 36 and/or valves 38 are selectively closed, with the selection depending upon the azimuthal orientation of the deflector relative to the window joint.

In the example of FIG. 7A, an inclined upper deflection face 54 of the deflector 52 is facing upward, in order to deflect the cutting tool 26 upwardly to form the window opening 28 and drill the branch wellbore 18. Thus, the line 22a will be damaged by the cutting tool 26. However, prior to the line 22a becoming damaged, the appropriate ones of the switches 36 and/or valves 38 are closed when the deflector 52 is positioned in the window joint 24, thereby isolating the line 22a prior to it being damaged.

To accomplish this result, the magnets 46 and/or 48 are carried on the deflector 52. In FIG. 7B, an end view of the magnets 46,48 shows the azimuthal orientation of these magnets relative to the deflector 52. Note that the magnet 46 is aligned with the deflection face 54 of the deflector

52, so that the switches 36 and/or valves 38 associated with the line 22a to be damaged by cutting through the sidewall of the window joint 24 will be appropriately opened (in the case of a switch) or closed (in the case of a valve) to isolate the line.

The other magnets 48 on the deflector 52 will cause appropriate ones of the switches 36 to be closed, and/or appropriate ones of the valves 38 to be opened, so that the undamaged line 22b will provide conductivity between the portions 20a, b of the circuit 20. Of course, if the switches 36 are normally closed and/or the valves 38 are normally open (e.g., by spring biasing, etc.), then the magnets 48 may not be used.

Although only one set of the magnets 46, 48 is depicted in FIG. 7A proximate the switches 36 and/or valves 38 in the control module 34b, another set of magnets could be positioned proximate the switches and/or valves in the other control module 34a, if desired.

It will be readily appreciated that one advantage of the well system 10 as depicted in FIG. 7A is that the deflector 52 can be in any azimuthal orientation relative to the window joint 24 and/or the wellbore 12, in order to drill the branch wellbore 18 in any azimuthal direction. Whatever the azimuthal orientation of the deflector 52 may be, appropriate ones of the switches 36 and/or valves 38 will be operated to isolate any one of the set 22 of lines which will be damaged by cutting through the sidewall of the window joint 24.

For example, if the deflector 52 is installed in the window joint 24 so that the deflection face 54 faces downward (thereby potentially causing damage to the line 22b as the window opening 28 is formed through the sidewall of the window joint 24), the magnets 46, 48 will cause appropriate ones of the switches 36 to be operated, and/or appropriate ones of the valves 38 to be operated, so that the line 22b to be damaged is isolated, and so that the undamaged line 22a will provide conductivity between the portions 20a, b of the circuit 20. Another significant advantage of the well system 10 of FIG. 7A is that such isolation and conductivity is accomplished prior to damage of any of the set 22 of lines. In this manner, difficulties due to loss of fluid, loss of pressure control or damage to sensitive electronic components is avoided. In addition, well tools 32 connected to the circuit 20 can be monitored, operated and controlled prior to, during and after damage to any of the set 22 of lines .

Referring additionally now to FIG. 8, the well system 10 is schematically illustrated after the window opening 28 has been cut through the sidewall of the window joint 24, the branch wellbore 18 (not shown in FIG. 8) has been drilled, and a tubular string 56 (such as a liner or production tubing string) has been installed through the window opening and into the branch wellbore. A hanger 58 secures and seals an upper end of the tubular string 56 within the tubular string 14.

A line 60 extends along the tubular string 56 for monitoring, controlling, etc. of one or more well tools (not shown) in the branch wellbore 18. This line 60 is advantageously connected to the circuit 20 upon installation of the tubular string 56, for example, by use of appropriate wet connect connectors of the type known to those skilled in the art. It is a particular advantage of the well system 10 as depicted in FIG. 8 that such connection can be accomplished, even though the line 22a has been damaged due to cutting through the sidewall of the window joint 24. Referring additionally now to FIG. 9, another example of the well system 10 is representatively illustrated in which valves 38a-f of the control modules 34a, b are mechanically-operated. Only valves 38a,b,d,e are visible in FIG. 9, but it will be appreciated that all of the valves 38a-f, or any number of valves, may be provided in the control modules 34a, b as desired. For clarity of illustration and description, the window joint 24, control modules 34a, b and set 22 of lines are depicted apart from the remainder of the system 10 in FIG. 9.

The valves 38a-f are initially maintained open by means of strength members 62a, b (such as cables, etc.) extending between operator members 42a,b,d,e of the respective valves 38a,b,d,e. However, bias members 64a,b,d,e (such as springs, etc.) function to bias the respective operator members 42a,b,d,e toward closed positions (i.e., to close the respective valves 38a,b,d,e).

Thus, all of the valves 38a,b,d,e remain open to thereby provide conductivity between the circuit portions 20a, b via the respective lines 22a, b unless one or more of the strength members 62a, b is severed. If, for example, the strength member 62a is severed (indicating that the line 22a is damaged, e.g., due to cutting of the opening 28 through the sidewall of the window joint 24), then the bias members 64a, d will cause the valves 38a, d to close, thereby isolating the line 22a from the circuit portions 20a, b. Similarly, if the strength member 62b is severed (indicating that the line 22b is damaged), then the bias members 64b, e will cause the valves 38b, e to close, thereby isolating the line 22b from the circuit portions 20a, b.

Enlarged schematic views of the line 22a, strength member 62a, valves 38a, d and bias members 64a, d are depicted in FIGS. 10 A&B apart from the remainder of the well system 10. The valves 38a, d are open in FIG. 1OA prior to severing of the strength member 62a and damaging of the line 22a, and the valves 38a, d are closed in FIG. 1OB after severing of the strength member 62a and damaging of the line 22a.

Thus, it will be appreciated that this configuration of the well system 10 and control modules 34a, b provides for simple, reliable and inexpensive isolation of the line 22a (or any of the set 22 of lines) in the event of damage to the line.

In FIG. 11, a manner of enhancing the reliability of the system 10 is representatively illustrated. Specifically, the associated lines 22a-c and strength members 62a-c are contained together in respective conduits 66a-c which extend longitudinally along the window joint 24.

These conduits 66a-c ensure that the associated lines 22a-c and strength members 62a-c are maintained closely adjacent each other, so that one of the lines will not become damaged without its associated strength member also being severed. In the example of FIG. 11, cutting through the window joint 24 at any azimuthal orientation within a relatively wide arc a will result in both severing of the strength member 62a and damage to the line 22a.

Referring additionally now to FIG. 12, another mechanically means of operating the valves 38a-f is representatively illustrated. In this example, the strength member 62a is looped about the operator members 42a, d (or sheaves, etc. associated with the operator members), and multiple lines 22a,d,e,f are positioned between the opposite sides of the strength member.

In this manner, damage to the lines 22a,d,e,f from either side (such as a cut 68 as depicted in FIG. 12) will be indicated reliably by severing of the strength member 62a, thereby allowing the bias members 64a, d to displace the operator members 42a, d to their closed positions and isolating the lines from the remaining undamaged portions of the circuit 20. Note that it is not necessary for the looped strength member 62a to straddle multiple lines 22a,d,e,f, since the strength member could straddle any number of lines, including one.

Referring additionally now to FIG. 13, another example of the well system 10 is representatively illustrated, in which multiple locations for damage to lines in the circuit 20 are contemplated. For example, such a situation could exist if multiple window openings 28 are to be cut through a tubular string 14 in order to drill multiple branch wellbores 18.

In FIG. 13, two locations for such damage are provided for by using three control modules 34a-c. The set 22 of lines 22a-c extends between the control modules 34a, b as described above, and another set 68 of lines 68a-c extends between the control modules 34b, c.

As depicted in FIG. 13, lines 22a, b have been damaged, but line 22c provides conductivity between the control modules 34a, b. In addition, line 68c has been damaged, but lines 68a, b provide conductivity between the control modules 34b, c. Thus, even though lines have been damaged at two separate locations along the circuit 20, conductivity is still provided between the circuit portions 20a,b.

The switches 36a-i in the control modules 34a-c are in the form of transistors (depicted in FIG. 13 as field-effect transistors). Operation of the switches 36a-i is controlled by associated programmed processors 70a-c (such as programmable microprocessors) connected to the switches. The processors 70a-c monitor appropriate conditions relating to the respective lines 22a-c and 68a-c and automatically isolate any damaged line(s) as such damage occurs. Diodes 72a-i provide for isolation at an opposite end of a damaged line. For example, the processor 70a, upon detecting a loss of conductivity through the line 22a or a short of that line to ground, may operate the switch 36a to isolate the line from the control module 34a and circuit portion 20a. The diode 72d prevents current from flowing from the control module 34b through the damaged line 22a.

Referring additionally now to FIG. 14, another example of the well system 10 is schematically illustrated. In this example, each of the sets 22, 68 of lines comprises both electrical and hydraulic lines. Accordingly, the circuit 20 is representatively an electrical circuit, and another circuit 80 is representatively a hydraulic circuit.

The processors 70a-c, in addition to controlling operation of the switches 36a-i as described above, also control operation of valves 38a-i. In this example, the valves 38a-i are solenoid-operated shuttle valves.

The processors 70a-c monitor appropriate conditions relating to the respective lines 22d-f and 68d-f, and automatically isolate any damaged line(s) as such damage occurs. Check valves 74a-i provide for isolation at an opposite end of a damaged hydraulic line. For example, the processor 70a, upon detecting an abnormal pressure or flow through the line 22d, may operate the valve 38a to isolate the line from the control module 34a and circuit portion 80a. The check valve 74d prevents fluid from flowing from the control module 34b through the damaged line 22d.

The processors 70a-c also provide for isolation of damaged electrical lines 22a-c and 68a-c between the control modules 34a-c at the two locations as described above. Thus, both electrical and hydraulic conductivity, and isolation of damaged electrical and hydraulic lines, are provided for in the example of FIG. 14. Referring additionally now to FIG. 15, another example of the well system 10 is schematically illustrated. In this example, the locations for possible damage to the circuits 20, 80 are more widely separated, and multiple well tools 32a, b are operated by pressure and fluid flow transmitted by the circuit 80, and by electric signals transmitted by the circuit 20.

The well tools 32a, b include respective actuators 76a, b and control valves 78a, b. The control valves 78a, b are representatively electrically-operated shuttle valves which respond to signals transmitted by the circuit 20 to alternately isolate the respective actuators 76a, b from the circuit 80, connect the actuators to the circuit 80 in a manner to displace respective pistons 82a, b in one direction, and connect the actuators to the circuit 80 in a manner to displace the pistons in an opposite direction. The control valves 78a, b are preferably independently operable, so that one of the actuators 76a, b may be operated in one manner, while another of the actuators may be operated in another manner, as desired. Another difference between the well system 10 as illustrated in FIGS. 14 & 15 is that the well system of FIG. 15 provides for two-way fluid flow in the hydraulic circuit 80. That is, portions 80a-c of the circuit 80 are parts of a hydraulic supply side of the circuit (as indicated by arrows 84), and portions 80d-f are parts of a hydraulic return side of the circuit (as indicated by arrows 86). The set 22 of lines includes electrical lines 22a-c, hydraulic supply lines 22d-f and hydraulic return lines 22g- i. Similarly, the set 68 of lines includes electrical lines 68a-c, hydraulic supply lines 68d-f and hydraulic return lines 68g-i. The set 22 of lines 22a-i extend between the control modules 34a, b at a first location where damage to the circuits 20, 80 is expected (for example, due to forming a window opening 28 through a sidewall of a tubular string 14), and the set 68 of lines 68a-i extend between the control modules 34c, d at a second location where damage to the circuits 20, 80 is expected (for example, due to forming another window opening through the sidewall of the tubular string) .

As depicted in FIG. 15, damaged lines 22a,b,d,e,g,h and 68f,c,i are isolated by respective pairs of valves

38a, b, f , i, j ,k and check valves 74a, b, f ,i, j ,k, and respective pairs of switches 36a, b,f and diodes 72a,b,f. However, lines 22f,c,i and lines 68a,b,d,e,g,h provide hydraulic and electrical conductivity between the pairs of control modules 34a, b and 34c, d and thereby provide for conductivity between the respective hydraulic circuit portions 80a-f and electrical circuit portions 20a-c.

In this manner, the multiple well tools 32a, b can be operated on either side of the pairs of control modules 34a, b and 34c, d. Of course, any number of well tools 32 can be operated in conjunction with any number of pairs of control modules 34 straddling any number of locations where damage to one or more circuits is expected.

It may now be fully appreciated that the above description of the various examples of the well system 10 and associated method provides many advancements to the art of providing circuits in subterranean wells. For example, the well system 10 allows for damage to occur to lines in the circuits, without such damage preventing operation of the circuits or associated well tools. When used in conjunction with drilling of branch wellbores, the well system 10 allows a window joint to be made of readily available and relatively inexpensive casing or liner material, and without provision for special orienting devices or procedures to prevent damage to circuits extending along the window joint. In particular, a subterranean well system 10 is described above which includes a circuit 20 extending in the well to a well tool 32, and a first set 22 of multiple redundant lines 22a-c at a first location along the circuit 20. Each of the first set 22 of lines 22a-c is capable of providing conductivity between first and second portions 20a, b of the circuit 20.

The first set 22 of lines 22a-c may extend longitudinally along a tubular string 14. An opening 28 may be formed through a sidewall of the tubular string 14 at the first location, and at least one of the first set 22 of lines 22a-c may be damaged due to formation of the opening 28.

A first control module 34a may be interconnected between the first set 22 of lines 22a-c and the first circuit portion 20a, and may be operative to isolate a damaged one of the first set 22 of lines 22a-c from the first circuit portion 20a.

The first set 22 of lines 22a-c may comprise hydraulic lines. The first control module 34a may comprise valves 38a-c for isolating each of the first set 22 of lines 22a-c from the first circuit portion 20a. The first set 22 of lines 22a-c may comprise electrical lines. The first control module 34a may comprise switches 36a-c for isolating each of the first set 22 of lines 22a-c from the first circuit portion 20a. The first set 22 of lines 22a-c may comprise optical lines. The first control module 34a may comprise optical switches 36a-c for isolating each of the first set 22 of lines 22a-c from the first circuit portion 20a-c.

A second control module 34b may be interconnected between the first set 22 of lines 22a-c and the second circuit portion 20b, and may be operative to isolate the damaged one of the first set 22 of lines 22a-c from the second circuit portion 20b.

A second set 68 of multiple redundant lines 68a-c may be provided at a second location along the circuit 20. Each of the second set 68 of lines 68a-c may be capable of providing conductivity between second and third control modules 34b, c with the third control module being connected to the second circuit portion 20b, and the second control module being connected between the first and second sets 22, 68 of lines.

A first control module 34a may be interconnected between the first set 22 of lines and the first circuit portion 20a and may be operative to isolate a damaged one of the first set 22 of lines from the first circuit portion 20a. A second control module 34b may be interconnected between the first set 22 of lines and the second circuit portion 20b and may be operative to isolate the damaged one of the first set 22 of lines from the second circuit portion 20b. A third control module 34c may be interconnected between the second circuit portion 20b and a second set 68 of lines and may be operative to isolate a damaged one of the second set 68 of lines from the second circuit portion 20b. A fourth control module 34d may be interconnected between the second set 68 of lines and a third circuit portion 20c and may be operative to isolate the damaged one of the second set 68 of lines from the third circuit portion 20c.

The above description also provides a method of providing conductivity across a damaged portion of a circuit 20 in a subterranean well. The method includes the steps of: damaging at least one line of a set 22 of redundant lines 22a-c extending along a tubular string 14; and isolating the damaged at least one line from an undamaged portion 20a, b of the circuit 20.

The method may further include the step of cutting an opening 28 through a sidewall of the tubular string 14. The damaging of the line may occur as a result of the cutting step. The circuit 20 may extend from a remote location, across the opening 28 and to a well tool 32.

The isolating step may further include operating at least one electrical switch 36 to thereby prevent electrical current flow between the damaged at least one line and at least a portion 20a, b of the circuit 20.

The isolating step may further include operating at least one optical switch 36 to thereby prevent transmission of light between the damaged at least one line and at least a portion 20a, b of the circuit 20.

The isolating step may further include operating at least one valve 38 to thereby prevent fluid flow between the damaged at least one line and at least a portion 20a,b of the circuit 20. The isolating step may be performed in response to the damaging step. The isolating step may be performed prior to the damaging step.

The method may include interconnecting a control module 34a between the first set 22 of lines 22a-c and a portion

20a of the circuit 20. The control module 34a may include a processor 70a programmed to detect the damaging of the at least one of the lines 22a-c and in response to cause the isolating of the damaged at least one of the lines 22a-c from the portion 20a of the circuit 20.

The processor 70a may cause operation of at least one of an electrical switch 36, an optical switch 36 and a valve 38 to thereby isolate the damaged at least one of the lines 22a-c from the portion 20a of the circuit 20. Of course, a person skilled in the art would, upon a careful consideration of the above description of representative embodiments of the disclosure, readily appreciate that many modifications, additions, substitutions, deletions, and other changes may be made to the specific embodiments, and such changes are contemplated by the principles of the present disclosure. Accordingly, the foregoing detailed description is to be clearly understood as being given by way of illustration and example only, the spirit and scope of the present invention being limited solely by the appended claims and their equivalents.

Claims

WHAT IS CLAIMED IS:

1. A subterranean well system, comprising: a circuit extending in the well to a well tool; and a first set of multiple redundant lines at a first location along the circuit, each of the first set of lines being capable of providing conductivity between first and second portions of the circuit.

2. The well system of claim 1, wherein the first set of lines extend longitudinally along a tubular string.

3. The well system of claim 2, wherein an opening is formed through a sidewall of the tubular string at the first location, and at least one of the first set of lines is damaged due to formation of the opening.

4. The well system of claim 1, wherein a first control module interconnected between the first set of lines and the first circuit portion is operative to isolate a damaged one of the first set of lines from the first circuit portion.

5. The well system of claim 4, wherein the first set of lines comprise hydraulic lines, and wherein the first control module comprises valves for isolating each of the first set of lines from the first circuit portion.

6. The well system of claim 4, wherein the first set of lines comprise electrical lines, and wherein the first control module comprises switches for isolating each of the first set of lines from the first circuit portion.

7. The well system of claim 4, wherein the first set of lines comprise optical lines, and wherein the first control module comprises optical switches for isolating each of the first set of lines from the first circuit portion.

8. The well system of claim 4, wherein a second control module interconnected between the first set of lines and the second circuit portion is operative to isolate the damaged one of the first set of lines from the second circuit portion.

9. The well system of claim 1, further comprising a second set of multiple redundant lines at a second location along the circuit, each of the second set of lines being capable of providing conductivity between second and third control modules, with the third control module being connected to the second circuit portion, and the second control module being connected between the first and second sets of lines.

10. The well system of claim 1, wherein a first control module interconnected between the first set of lines and the first circuit portion is operative to isolate a damaged one of the first set of lines from the first circuit portion, a second control module interconnected between the first set of lines and the second circuit portion is operative to isolate the damaged one of the first set of lines from the second circuit portion, a third control module interconnected between the second circuit portion and a second set of lines is operative to isolate a damaged one of the second set of lines from the second circuit portion, and a fourth control module interconnected between the second set of lines and a third circuit portion is operative to isolate the damaged one of the second set of lines from the third circuit portion.

- SO ¬

IL A method of providing conductivity across a damaged portion of a circuit in a subterranean well, the method comprising the steps of: damaging at least one line of a set of redundant lines extending along a tubular string; and isolating the damaged at least one line from an undamaged portion of the circuit.

12. The method of claim 11, further comprising the step of cutting an opening through a sidewall of the tubular string, wherein the damaging step occurs as a result of the cutting step.

13. The method of claim 12, wherein the circuit extends from a remote location, across the opening and to a well tool.

14. The method of claim 11, wherein the isolating step further comprises operating at least one electrical switch to thereby prevent electrical current flow between the damaged at least one line and at least a portion of the circuit.

15. The method of claim 11, wherein the isolating step further comprises operating at least one optical switch to thereby prevent transmission of light between the damaged at least one line and at least a portion of the circuit.

16. The method of claim 11, wherein the isolating step further comprises operating at least one valve to thereby prevent fluid flow between the damaged at least one line and at least a portion of the circuit.

17. The method of claim 11, further comprising the step of interconnecting a control module between the set of lines and a portion of the circuit, the control module including a processor programmed to detect the damaging of the at least one of the lines and in response to cause the isolating of the damaged at least one of the lines from the portion of the circuit.

18. The method of claim 17, wherein the processor causes operation of at least one of an electrical switch, an optical switch and a valve to thereby isolate the damaged at least one of the lines from the portion of the circuit.

19. The method of claim 11, wherein the isolating step is performed in response to the damaging step.

20. The method of claim 11, wherein the isolating step is performed prior to the damaging step.