APPARATUS AND SYSTEM TO DRILL A BORE USING A LASER

Abstract

A system to extend a lateral bore section using laser light comprises a first umbilical connected to a deflection member having a drive gear, a lateral exit port and at least one deployable seal intermediate a proximal end and the lateral exit port, and a second umbilical having an exterior movable by the drive member through a pathway of the deflection member ending at the lateral exit port to controllably advance a drill head connected to a leading end of the second umbilical. Optical fibers of the second umbilical transmit laser light from a surface end to optical elements in the drill head that condition laser light for heating a targeted portion of a bore wall. The first umbilical positions the deflection member within a primary bore section, and the second umbilical is controllably advanced to extend a lateral bore by the drive gear of the deflection member.

Description

STATEMENT OF RELATED APPLICATIONS

This application claims priority to and depends to International PCT/US2012/055768 filed on 17 Sep. 2012, which claims priority to and depends from Hungarian application no. P1100517 filed on 15 Sep. 2011, and Hungarian application no. P1100665 filed on 1 Dec. 2011.

BACKGROUND

1. Field of Invention

The present invention relates to the drilling of earthen bores to recover fluids residing in subterranean geologic formations. More specifically, the present invention relates to an apparatus and system to extend a bore section into a geologic formation using a laser drilling apparatus.

2. Background of the Related Art

Borehole systems are drilled into the earth's crust to penetrate subsurface geologic formations bearing a formation fluid, such as water, oil or gas, to facilitate the production of the formation fluid to the surface. A bore system may comprise a single bore surrounded by a bore wall or, alternately, a primary bore having one or more intersecting lateral bores surrounded, along with the primary bore, by a common bore wall.

A bore system may be bored in the earth's crust using conventional mechanical drilling rigs at the earth's surface to rotate a drill bit at a leading end of a drill string extending from the rig. Some rigs rotate the entire drill string, which may comprise a plurality of segments or stands of drill pipe threadedly coupled to form an elongate drill string. The drill string can be made up by adding segments as the drill string is extended deeper into the earth's crust or laid down by removing segments as the drill string is withdrawn from the earth's crust. The rotation of the drill string and the drill bit at the leading end of the drill string, while urging the drill bit against an end of a primary bore or lateral bore section to be extended, breaks apart rock engaged by the drill bit.

Alternately, a drill string may comprise a mud motor proximal to the leading end and hydraulically powered by pressurized fluid provided through the center of the drill string to rotate a drill bit coupled to the mud motor to break apart the rock engaged by the drill bit. With a mud motor or a conventional drill string, drill cuttings are removed from the portion of the bore to be extended by circulating working fluid down the drill string and back to the earth's surface through the annulus between the drill string and the wall of the bore.

Still other systems and methods for extending a section of a bore system include the use of a high-pressure jet to mechanically fracture rock within a fluid path adjacent to a liquid jet at the leading end of a drill string. High-pressure “jet” drilling may include the removal of debris resulting from the drilling process by circulating fluid into and from the portion of the borehole system being extended. For best results, the jet path between the liquid jet nozzle and the portion of the bore wall to be jet blasted should be as short as possible to impart a maximum amount of liquid kinetic energy on the targeted portion of the bore wall to be extended.

A method for extending a section of a bore system includes the use of a laser drill head connected to a leading end of a drill string. The drill head is used to introduce laser light into the bore section to heat, melt and/or vaporize at least some components of the geologic formation exposed to a laser path adjacent to the drill head. Unlike a conventional drilling system that forcibly engages a drill bit against the wall of a bore section, a laser drilling process generally requires that the portion of the drill head from which the laser light is emitted remains in close proximity to, but not in actual contact with, the targeted portion of the wall of the bore section to be extended. A laser path between the drill head and a targeted portion of the bore wall to be extended is irradiated using the drill head.

Extending bore sections using laser drill heads generally requires that the portion of the bore section intermediate the drill head and the targeted portion of the wall of the bore section be cleared of laser-obstructing material. Unwanted accumulation of debris on laser emitting portions of the drill head impairs drilling performance by obstructing efficient transmission of emitted laser light to impinge on the targeted portion of the wall of the bore section to be extended. Optimal results can be obtained when the laser emitting drill head can be controllably advanced within the bore section as debris is removed, and when contaminants can be either prevented from being deposited onto or in the way of laser emitting portions of the drill head or removed from laser emitting portions of the drill head to maintain drilling performance.

BRIEF SUMMARY OF THE INVENTION

One embodiment of the present invention provides a system to controllably advance a laser emitting drill head to extend a targeted portion of a wall of a bore section that is lateral to and intersects a primary bore. The system comprises a first umbilical connected to a deflection member having proximal end, a distal end, a gear drive, a lateral exit port and an umbilical pathway adjacent to the drive gear and intersecting the lateral exit port. The first umbilical is used to position the deflection member within a primary bore and comprises either a fluid conduit or an electrically conductive member to deliver pressurized fluid or electrical current, respectively, to a motor in the deflection member to operate the drive gear. The first umbilical is used to position the deflection member within a primary bore adjacent to a desired lateral bore to be created and/or extended using the system of the present invention. The deflection member receives and cooperates with a second umbilical having a fluid conduit and a plurality of optically transmitting fibers and connected at a leading end of the second umbilical to a drill head.

The drill head comprises at least one optical element to receive laser light from a plurality of optically transmitting fibers within the second umbilical and to emit laser light to impinge on a targeted portion of a bore wall. The drill head further comprises a fluid jumper conduit connected to a fluid nozzle to receive pressurized fluid from the fluid conduit of the second umbilical. The drill head may be adapted to inject a stream of the fluid to displace laser-obstructing materials from a laser light path intermediate the optical element and the targeted portion of the bore wall. The drill head may also be adapted to inject a stream of the fluid to protect and cool a laser emitting portion of the drill head, as will be discussed in greater detail below. The second umbilical comprises an exterior portion disposed generally proximal to the drill head that is shaped and sized to be engaged and driven by one or more drive gears driven by the motor of the deflection member. In one embodiment, the exterior portion of the second umbilical comprises a series of corrugations having a generally uniform spacing and a generally uniform radial height for engagement by the one or more drive gears of the deflection member such that, upon operation of the one or more drive gears, the second umbilical is controllably advanced through the umbilical pathway of the deflection member. This cooperative arrangement between the deflection member at the leading end of the first umbilical and the exterior portion of the second umbilical that is proximal to the leading end of the second umbilical enables the laser-emitting drill head at the leading end of the second umbilical to be controllably advanced to extend a targeted portion of the bore wall adjacent to the lateral exit port of the deflection member. In another embodiment, the exterior portion of the second umbilical comprises a spirally-wound thread having a generally uniform pitch and height for engagement with a mating spirally-wound thread within one or more drive gears of the deflection member such that, upon operation of the motor to rotate the one or more drive gears, the second umbilical is controllably moved through the umbilical pathway of the deflection member to controllably advance the drill head connected to the leading end of the second umbilical to extend targeted portion of the bore wall adjacent to the lateral exit port of the deflection member.

It may be desirable to isolate or to substantially isolate portions of the bore system being extended from other portions of the bore system in order to control the environment proximal to the drill head. Embodiments of the system of the present invention include a deflection member that may be adapted to sealably engage a wall of the primary bore and to thereby facilitate the displacement of laser-obstructing materials within the primary bore from a laser light path intermediate the laser emitting portion of the drill head being controllably advanced by the drive gear and a targeted portion of a bore wall to be extended using the drill head. In one embodiment, the system comprises a deflection member having a circumferentially deployable seal intermediate the proximal end and the lateral exit port of the deflection member. The circumferentially deployable seal is connected, through a valve, to a fluid conduit within the first umbilical that provides, upon opening of the valve, pressurized fluid to expand the circumferentially deployable seal radially outwardly from the deflection member to engage and seal against the wall of the primary bore in which the deflection member is positioned using the first umbilical. In one embodiment, the first umbilical may comprise a second fluid conduit to provide displacement fluid into the primary bore at a location distal to the circumferentially deployable seal, that is, at a location opposite the deployable seal from the proximal end of the deflection member, to displace laser-obstructing materials from a laser light path intermediate the drill head connected to the second umbilical and the targeted portion of the bore wall adjacent thereto. Either the first fluid conduit or the second fluid conduit, if any, of the first umbilical provides power fluid to operate the motor that drives the one or more drive gears of the deflection member.

In another embodiment, the system may comprise a deflection member having a proximal circumferentially deployable seal, intermediate the proximal end and the lateral exit port of the deflection member, and a distal circumferentially deployable seal intermediate the lateral exit port and the distal end of the deflection member. The proximal and distal circumferentially deployable seals may be connected, through one or more valves, to a fluid conduit within the first umbilical that provides, upon opening of the one or more valves, pressurized fluid to expand the proximal and distal circumferentially deployable seals radially outwardly from the deflection member to engage and seal against the wall of the primary bore in which the deflection member is positioned using the first umbilical. The first umbilical may also comprise a second fluid conduit to provide displacement fluid into the primary bore at a location intermediate the proximal and distal circumferentially deployable seals of the deflection member to displace laser-obstructing materials from a laser light path intermediate the drill head connected to the second umbilical and the targeted portion of the bore wall adjacent thereto. The deflection member may include features to assist in removal of laser obstructing materials trapped between the deployed proximal and distal circumferentially deployable seals. For example, a distal circumferentially deployable seal bypass conduit within the deflection member may enable laser-obstructing fluid trapped intermediate the proximal and distal circumferentially deployable seals to be displaced to a portion of the primary bore that is distal to the distal circumferentially deployable seal of the deflection member. An equalization bypass conduit within the deflection member may enable fluid within a portion of the primary bore distal to the deflection member to be displaced to the portion of the primary bore proximal to the deflection member to equalize the pressure above and below, or proximal to and distal to, the deflection member. A combination of a distal circumferentially deployable seal bypass conduit and an equalization conduit within a deflection member enables both the displacement of laser-obstructing material trapped intermediate the proximal and distal circumferentially deployable seals to the portion of the primary bore distal to the deflection member and the equalization of pressure between the portion of the primary bore distal to the deflection member and the portion of the primary bore proximal to the deflection member.

Another embodiment of the system comprises a deflection member having a non-circumferential deployable seal surrounding the lateral exit port through which the umbilical pathway extends. The non-circumferential deployable seal comprises a sealing surface that, upon deployment of the seal, engages the wall of the primary bore to surround the targeted portion of the bore wall and isolate it from the primary bore except for the lateral exit port for the umbilical pathway through the deflection member. The sealing surface of the non-circumferential deployable seal surrounds the lateral exit portion of the deflection member and wraps around a portion of the deflection member. Displacing fluid provided to displace laser-obstructing material from the laser light path intermediate the drill head, at the leading end of the second umbilical movable within the umbilical pathway of the deflection member, and the targeted portion of the bore wall is, during operation of the drill head, forced to move from a lateral bore being extended and through the umbilical pathway to prevent laser-obstructing fluid from re-entering the laser light path.

The system and apparatus of the present invention facilitate the unimpeded impingement of laser light on a targeted portion of a bore wall to be extended. The formation materials that make up the bore wall are heated by impingement of laser light emitted from the drill head. Globules of melted formation materials are formed and then swept from the bore wall by continued injection of the laser conductive material, such as clear liquid or gas. Depending on the composition of the formation and fluid residing therein, some components of the formation may vaporize within the bore section, but most solid components will burn, vaporize or melt. Dust, molten formation components, and fragments and bits of formation components, in addition to vaporized remnants of formation fluids, are generated by the use of laser light to extend a bore section. These contaminants can impinge on and adhere to, mar or otherwise tarnish the laser emitting portion of the drill head, resulting in an overall loss of drilling efficiency due to impairment of unobstructed laser light transmission from the drill head to the targeted portion of the bore wall.

In another embodiment, the present invention provides a drill head to extend a bore section into a subsurface geologic formation. The drill head is connectable to and positioned within a bore using an umbilical. The drill head comprises an optical element to receive laser light from optically transmitting fibers within the umbilical and to emit laser light to impinge on a targeted portion of a bore wall to be extended thereby. The drill head is further connectable to a fluid conduit within the umbilical and comprises a fluid nozzle connected to the fluid conduit to inject a fluid stream directed generally adjacent to a laser emitting portion of the drill head to provide a protective barrier against debris impinging upon the laser emitting portion.

In another embodiment, the present invention provides a drill head to extend a bore section into a subsurface geologic formation. The drill head is connectable to and positioned within a bore using an umbilical. The drill head comprises an optical element to receive laser light from optically transmitting fibers within the umbilical and to emit laser light to impinge on a targeted portion of a bore wall to be extended thereby. The drill head is further connectable to a leading end of a fluid conduit within the umbilical and comprises a fluid jumper conduit terminating at a fluid nozzle to receive fluid provided to the nozzle from the fluid conduit and through the fluid jumper conduit if the drill head. The fluid nozzle injects a fluid stream immediately anterior to the laser emitting portion of the drill head. The fluid nozzle may dispose the fluid stream to impinge on the laser emitting portion of the drill head or it may dispose the fluid stream to a position immediately adjacent to the laser emitting portion. In one embodiment, a transparent barrier is positioned on the drill head and within a laser light path extending from the laser emitting portion of the drill head. In this embodiment, the fluid stream injected from the fluid nozzle is disposed immediately anterior to and/or to impinge on the transparent barrier to provide an additional protective barrier against debris impinging upon the transparent barrier. Additionally, the fluid stream injected at the fluid nozzle provides a stream of fluid to remove heat from the transparent barrier on the drill head or from the laser emitting portion of the drill head, and the fluid stream may impinge upon and remove debris from the transparent barrier or the laser emitting portion to prevent the debris from adhering to the transparent barrier or the laser emitting portion.

In another embodiment, the present invention provides a drill head to extend a bore section into a subsurface geologic formation. The drill head is connectable to a leading end of an umbilical and positionable within an earthen bore using the umbilical. The drill head comprises an optical element to receive laser light from optically transmitting fibers within the umbilical and emits laser light from the optical element to impinge on a targeted portion of a bore wall to be extended thereby. The drill head is further connectable to a leading end of a fluid conduit within the umbilical and comprises a fluid jumper conduit terminating at a fluid nozzle to receive fluid provided through the fluid conduit and to inject a fluid stream into the bore section immediately anterior to the laser emitting portion of the drill head. The nozzle comprises an opening through which the injected fluid exits to displace a movable protective member disposed immediately anterior to the laser emitting portion of the drill head from a first position, generally shielding the laser emitting portion of the drill head from debris, to a second position providing a laser light path through which laser light may pass to impinge on a targeted portion of a bore wall. In the first position, the movable protective member obstructs debris from contacting the laser emitting portion of the drill head, and in the second position, the protective member is removed from the obstructing position to permit laser light emitted from the laser emitting portion of the drill head to impinge on a targeted portion of a bore wall adjacent to the drill head. In one embodiment, the protective member comprises a unitary portion that is biased towards the first, obstructing position using a spring element. In another embodiment, the protective member comprises a plurality of cooperating portions, each biased towards a first, obstructing position using a spring element. In another embodiment, the protective member comprises a unitary portion that is spring biased towards the first, obstructing position using an elastomeric member such as, for example, a temperature-resistant rubber or rubberized element. In another embodiment, the protective member may comprise a plurality of protective member portions, each spring biased towards a first, obstructing position by elastomeric members such as, for example, a plurality of rubber or rubberized elements. The unitary protective member may be fastened to a drill head structure, which is a portion of or an extension of the drill head generally adjacent to a leading end of the drill head proximal to the laser emitting portion of the drill head. Where the protective member comprises a plurality of protective member portions, the plurality of protective member portions may be fastened to the drill head structure. The protective member or protective member portions may be formed of a rigid, temperature-resistant material such as metal or ceramic, and may be coupled to the drill head structure through a hinge to facilitate the displacement of the protective member from the first, protecting position anterior to the laser emitting portion of the drill head to a second, removed position to open a laser light path from the laser emitting portion to the targeted portion of a bore wall. Where the protective member is elastomeric, a hinge or other coupling may not be needed if the fluid pressure brought to bear on the protective member by the fluid nozzle disposed adjacent to the protective member is sufficient to displace the protective member from the first position to the second position.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a schematic illustrating an embodiment of a system of the present invention.

FIG. 2 is perspective view of an alternative spool that can be used to store an umbilical of a system of the present invention.

FIG. 3 is a top view of a second alternative spool that can be used to store an umbilical of a system of the present invention.

FIG. 4 is a perspective view of a portion of an embodiment of an apparatus, a drill head connected to an umbilical, which can be used to implement one embodiment of the system of the present invention.

FIG. 5 is a sectional elevation view of an embodiment of a portion of the system of FIG. 1 having a deflection member positioned using a first umbilical and having an umbilical pathway and a drive gear therein to receive and engage, respectively, a second umbilical.

FIG. 6 is a side sectional elevation view of an alternative embodiment of the deflection member of the system of the present invention.

FIG. 7 is a frontal elevation view of the alternative embodiment of the deflection member of FIG. 6.

FIG. 8 is a top sectional view of the alternative embodiment of the deflection member of FIGS. 6 and 7.

FIG. 9 is a section view of an embodiment of a drill head of the present invention having a fluid conduit connected to a plurality of fluid nozzles to inject a plurality of fluid streams to protect a plurality of laser emitting portions of the drill head from contact by debris generated by the laser drilling process.

FIG. 10 is a section view of an embodiment of a drill head of the present invention having a fluid conduit connected to a plurality of fluid nozzles to inject a plurality of fluid streams to protect a transparent member disposed on the drill head and within the laser light path intermediate a laser emitting portion of the drill head and a targeted portion of a bore wall.

FIG. 11 is a section view of an embodiment of a drill head of the present invention having a plurality of laser emitting portions protected from debris within the bore in which the drill head is positioned by a plurality of pivoting protective members in a closed position and movable to an open position by the introduction of fluid pressure adjacent to the laser emitting portions.

FIG. 12 is an enlarged view of one of the laser emitting portions of the embodiment of the drill head of FIG. 11 protected from debris by a pivotable protective member in a closed position.

FIG. 13 is the enlarged view of FIG. 12 after fluid is introduced through a nozzle adjacent to the laser emitting portion of the drill head to pivot the protective member from the closed position of FIGS. 11 and 12 to an open position to facilitate the impingement of laser light from the laser emitting portion of the drill head to a targeted portion of a bore wall.

FIG. 14 is an alternative embodiment of the drill head of FIGS. 11-13 comprising a protective member comprising a plurality of cooperating protective member portions in a closed position to obstruct the emission of laser light from the laser emitting portion of a drill head and to protect the laser emitting portion from debris in the bore.

FIG. 15 is the alternative embodiment of FIG. 14 after fluid pressure is introduced through a nozzle adjacent the laser emitting portion of the drill head to deform the protective member portions from the closed configuration to an open configuration.

DETAILED DESCRIPTION

One embodiment of the present invention provides an apparatus and system to extend an earthen bore section comprising a first elongate umbilical to position a deflection member within a primary bore and a second elongate umbilical connected at a leading end to a drill head. The second umbilical and the drill head cooperate with the deflection member to position and controllably advance the drill head to extend a lateral bore intersecting the primary bore. The first umbilical includes a fluid conduit to pressurize, expand and deploy one or more deployable seals on the deflection member to engage and seal against the wall of the bore. The second umbilical also includes a fluid conduit to provide fluid to the drill head. In one aspect, the fluid provided to the drill head through the second umbilical displaces laser-obstructing materials from a laser light path intermediate a laser emitting portion of the drill head and a targeted portion of a bore wall to be extended using the drill head. The second umbilical further comprises a plurality of optically transmitting fibers to transmit laser light from a laser light generator at the earth's surface to an optical element within the drill head. The laser light is emitted from the optical element to impinge on the targeted portion of the bore wall.

In one embodiment, the first umbilical and the second umbilical are each stored on and fed into an earthen bore system from a reel, a spool or other storage device. A storage device on which an umbilical may be wound or coiled facilitates transportation of the umbilical to and from the surface location of the entry to the bore system to be extended thereby. The storage device may be rotated in a first direction to feed an umbilical stored thereon into a bore system and to position the deflection member coupled to the leading end of the first umbilical, or to position the drill head coupled to the leading end of the second umbilical, within the earthen. The storage device may be rotated in a reversed direction to retrieve the umbilical from the bore system and back onto the storage device.

A storage device may be connected to a rotatable fluid coupling that is coupled to a surface end of the fluid conduit of the umbilical to facilitate the flow of fluid from a fluid source at the earth's surface to a surface end of the fluid conduit of the umbilical. The fluid, which may be liquid or pressurized gas, is delivered through a fluid conduit within an umbilical to, for the first umbilical, the deflection member connected to the leading end of the first umbilical or, for the second umbilical, to the drill head connected to the leading end of the second umbilical. In embodiments of an umbilical having a second fluid conduit in addition to a first fluid conduit, an umbilical storage device may be connected to a second rotatable fluid coupling that receives a second fluid from a storage device on the surface connected to a surface end of the second fluid conduit.

Similarly, the storage device may be connected to a rotatable optical transmission coupling connected to a surface end of the optical fibers of the second umbilical to facilitate the transmission of laser light from a laser generator on the earth's surface to a surface end of the optically transmitting fibers of the second umbilical. The laser light is transmitted through the optical fibers of the second umbilical to optical elements in the drill head connected to the leading end of the second umbilical. The rotatable couplings may be connected to and used with the umbilical storage device to accommodate rotary movement of the umbilical storage device relative to the earth's surface while providing a continuous supply of fluid, laser light and even a second fluid without unwanted twisting or binding of the umbilical. Alternately, the laser generator may be disposed within the center of the spool about which the umbilical is wound or coiled.

The first umbilical comprises a leading end, to which the deflection member is connected, for being introduced into the bore system. The first umbilical storage device rotates to feed out the first umbilical into the bore system in an amount sufficient to position the drill head at the leading end of the first umbilical at a desired lateral bore section site. The deflection member is provided with one or more seals to facilitate the displacement, using a laser conductive fluid, of laser obstructing materials from the laser light path. The deflection member comprises a guide member to engage and deflect the drill head and the second umbilical connected thereto to a targeted portion of the bore wall. A deployable seal, which may be a circumferentially deployable seal, is disposed on the deflection member. Upon deployment of the deployable seal, such as be fluid pressure provided through the fluid conduit of the first umbilical, the seal expands to engage the bore wall to generally isolate a portion of the bore wall to be extended from a portion of the bore system that contains laser obstructing materials.

The second umbilical comprises a leading end, to which the drill head is connected, for being introduced into the bore system. The second umbilical storage device feeds out the second umbilical into the bore system in an amount sufficient to position the drill head at the leading end of the second umbilical proximal a portion of a bore wall to be extended using the drill head. The drill head comprises one or more fluid injection ports to introduce fluid supplied through the fluid conduit of the second umbilical to displace laser obstructing materials from a laser path intermediate the drill head and a targeted portion of the bore wall. Laser obstructing materials may include, but are not limited to, working fluid, drilling fluid, formation fluids and other fluids and debris, including debris generated by the laser drilling process. The laser light path, as that term is used herein, is the path through which the laser light emitted from the laser emitting portion of the drill head will beam to impinge on the targeted portion of the wall of the bore section to be extended using the drill head.

The drill head of the second umbilical may further comprise one or more optical elements at the laser emitting portion of the drill head to focus and/or condition the laser light transmitted via the optically transmitting fibers of the second umbilical from the surface. The optical elements may focus and/or condition the laser light for optimal heating of the targeted portion of the bore wall. The optical elements may comprise lenses housed at the laser emitting portion of the drill head and optically coupled to a leading end of optical fibers extending from the second umbilical and terminating at or within the drill head. The optical elements may be housed, for example, at an end of the drill head generally opposite a connected end of the drill head, and the optical elements may be protected using a movable protective member or by a stationary and transparent protective member such as, for example, glass or polycarbonate, through which emitted laser light may pass to impinge upon the targeted portion of the bore wall opposite the laser path from the laser emitting portion of the drill head.

In one embodiment, the deflection member connected to the leading end of the first umbilical comprises at least one deployable circumferential seal that is an inflatable member, and deployment of the seal may be implemented by remotely opening a valve fluidically coupled between the deployable seal and the leading end of the fluid conduit of the first umbilical used to position the deflection member within the bore. In one embodiment, the deployed seal may be retracted from the deployed configuration by closing the valve and by then remotely opening a second valve coupled to release the fluid from the deployed seal into the bore section. In another embodiment, the valve opened to introduce fluid from the fluid conduit to deploy the seal and the second valve coupled to release fluid from the deployed seal to the bore may be replaced with a single remotely-controllable three-way valve having a first selectable position, to establish communication between the fluid conduit of the umbilical and the deployable seal to inflate the seal, and a second selectable position to establish communication between the inflated seal and the bore section to deflate the seal.

The above-described system of the present invention comprises a drill head which may be used to extend a bore section of a bore system. Melted formation components and heated debris may be moved from the portion of the bore wall being extended to a portion of the bore having working fluid or drilling fluid so that it may be circulated to the surface and thereby removed from the bore system. Alternately, the debris may be swept, using fluid injected from the drill head and at the portion of the bore wall being extended, to a debris removal passage of the drill head where, using differential pressure, the debris is moved to a to the surface or to a portion of the bore containing working fluid or drilling fluid.

In one embodiment, a portion of the second umbilical proximal to the drill head connected at the leading end comprises an exterior portion with a lining to facilitate engagement and controllable advance of the second umbilical. The second umbilical may comprise a fluid conduit and a plurality of optical fibers and, in some embodiments, a debris removal channel. The exterior portion of the second umbilical is shaped and sized to be engaged and controllable advanced using a drive gear adjacent to an umbilical pathway of the deflection member through which the second umbilical passes. The operation of the drive gear in the deflection member cooperates with the exterior portion of the second umbilical to controllably advance and thereby position the drill head connected at the leading end of the second umbilical for extending a lateral bore.

FIG. 1 is a schematic illustrating an aspect of the system 10 of the present invention. A borehole 90 is drilled into the earth's crust 11 so that a portion 17 of the borehole 90 penetrates a geologic formation 19 bearing a fluid medium such as, for example, hydrocarbons. The system 10 comprises a first coiled tubing unit 130 at the surface 15 having a source of fluid 112 such as, for example, water or pressurized gas, that is fluidically coupled through a fluid leader 113 to a fluid conduit (not shown) within a first umbilical 134. The system 10 further comprises a second coiled tubing unit 30 at the surface 15 having a source of fluid 12 such as, for example, water or pressurized gas, that is fluidically coupled through a fluid leader 13 to a fluid conduit (not shown) within a second umbilical 34. The system 10 further comprises a portable electric generator 14 electrically coupled through a power supply leader 18 to power a laser light generator 16 that is, in turn, optically coupled through a laser leader 26 to a plurality of optical fibers 47 (not shown in FIG. 1) within the second umbilical 34. The system 10 of FIG. 1 comprises a wellhead 25 sealing the surface end 91 of the bore 90 through which the first umbilical 134 and the second umbilical 34 are received into the bore 90, a working fluid tank 20 coupled through a working fluid leader 22 to the wellhead 25 to enable the introduction and removal of working fluid 21 into and from an annulus 24 between the first umbilical 134 and the second umbilical 34, on the one hand, and the wall 94 of the bore 90, on the other hand. The system further comprises a first spool 130 on which an extended length of the first umbilical 134 may be stored, a second spool 30 on which an extended length of the second umbilical 34 may be stored, and a coiled tubing unit guide support 27 to support an umbilical guide 38 having a plurality of rolling elements 37 therein to reduce friction of movement of the first umbilical 134 and the second umbilical 34 into and from the wellhead 25 and the bore 90.

The first coiled tubing unit 130 and the second coiled tubing unit 30 of the system 10 each comprise a rotatable axles 132 and 32, respectively, enabling the spooling out and the spooling in of the first umbilical 134 and the second umbilical 34, respectively, using motors (not shown) and related gears (not shown). In FIG. 1, the first coiled tubing unit 130 has been reeled out to introduce a sufficient length of the first umbilical 134 through the wellhead 25 to position the deflection member 50 connected to a leading end 36 of the first umbilical 134 adjacent to a desired lateral bore location (not shown), and a deployable seal 54 has been deployed to engage the wall 94 of the bore 90 adjacent thereto. Also, the second coiled tubing unit 30 has been reeled out to introduce a sufficient length of the second umbilical 34 through the wellhead 25 to position the drill head (not shown) adjacent to a targeted portion of the wall 94 to be extended.

FIG. 2 is a perspective view of a second umbilical storage spool 32A that can be used to store the second umbilical 34 of a system of the present invention by coiling the second umbilical 34 against the interior wall 33 of the spool 32A. After a portion of the interior wall 33 is covered with outer coils 42 of the second umbilical 34, additional, smaller coils can be disposed within the initial, outer coils 42 for additional storage capacity. FIG. 3 is a top view of a another alternative umbilical storage spool 32B that can be used to store the second umbilical 34 of a system of the present invention by wrapping coils 44 around an exterior wall 41 of a center post 38 of the spool 34B. After a portion of the exterior wall 41 is covered with coils 44 of the umbilical 34, additional, larger coils can be disposed about the initial, inner coil 40 for additional storage capacity. It will be understood that these storage spools can also be used in conjunction with the first umbilical 134 of the system 10, and that the selection of the second umbilical 34 for use in the illustrations of FIGS. 2 and 3 is not exclusive.

FIG. 4 is a perspective view of a drill head 51 that can be connected to a leading end 34A of the second umbilical 34 and used to implement an aspect of the system 10 (not shown in FIG. 4) of the present invention. The drill head 51 comprises a plurality of optical elements 45 optically coupled to a plurality of elongate optical fibers 47 that optically conduct laser light (not shown) provided from the laser light source 16 (not shown—see FIG. 1) through the laser leader 26 (not shown—see FIG. 1) to a surface end (not shown—see FIG. 1) of the optical fibers 47. The optical elements 45 in the drill head 51 of FIG. 4 are disposed in a generally concentric pattern within a leading end 56 of the drill head 51. The optical elements 45 may be disposed in a number of various patterns or positions within the drill head 51.

The drill head of FIG. 4 further comprises at least one fluid injection port 46 disposed within the leading end 56 of the drill head 51 and positioned to inject a fluid provided through a fluid conduit 49 of the second umbilical 34 into a section of a bore (not shown in FIG. 4—see FIG. 1) adjacent a bore wall (not shown) to be extended using laser light (not shown) emitted from the optical elements 45 of the drill head 51. In the drill head 51 of FIG. 4, the fluid injection port 46 is disposed generally interior to a concentric pattern of optical elements 45. The fluid injection port 46 or, in other embodiments of the drill head 51, a plurality of fluid injection ports 46, may alternately be strategically disposed in a variety of positions within the drill head 51 to direct a stream of injected fluid into the bore section at a selected angle relative to an axis 62 of the drill head 51. The drill head 51 of FIG. 4 optionally comprises an optional debris removal passage 66 disposed to receive molten formation components and debris from a laser-heated portion of a bore wall (not shown) and to convey the debris (not shown) to the surface via the debris removal passage 66.

The second umbilical 34 illustrated in FIG. 4 and connected at its leading end 34A to the drill head 51 further comprises an exterior portion 67 having a series of corrugations 67A thereon that are sized and shaped to be engaged by a drive motor (not shown) within the deflection member 50 (not shown—see FIG. 5-8) with which the second umbilical 34 cooperates to controllably advance the drill head 51 within a bore (not shown) to be extended using the drill head 51. An interval of the exterior portion 67 is removed to reveal the optically transmitting fibers 47, the fluid conduit 49 and the optional debris removal passage 66 within the exterior portion 67 of the second umbilical 34. It should be noted that the exterior portion 67 terminates proximal to the leading end 34A of the second umbilical 34 and may extend several meters (see, for example, FIG. 5) along the second umbilical 34 from the drill head Si to facilitate controllable advance and positioning of the drill head 51 within a bore (not shown) to be extended, as will be described in more detail in the paragraphs that follow.

FIG. 5 is an enlarged section view the deflection member 50 cooperating with the second umbilical 34 and the drill head 51 connected thereto of one embodiment of the apparatus and system of the present invention positioned using a first umbilical 134 within a primary bore 90 to make and/or extend an intersecting lateral bore 88 within a geologic formation 19. The deflection member 50 of FIG. 5 comprises an exterior surface 59, a proximal circumferentially deployable seal 54 and a distal circumferentially deployable seal 154 to engage and seal against the wall 94 of the primary bore 90. The deflection member 50 further comprises a proximal end 89 and a distal end 93, and a lateral exit port 95 therebetween. The deflection member further comprises a guide member 76 therein to engage and deflect the drill head 51 to the lateral exit port 95 and a pair of drive gears 77 to engage the corrugations 67A along the exterior portion 67 of the second umbilical 34 to thereby controllably advance the movement of the drill head 51 connected to the second umbilical 34. The space between the drive gears 77, the space along the guide member 76 and the lateral exit port 95 are portions of an umbilical pathway 99 of the deflection member 50 that cooperates with the second umbilical 34, specifically with the exterior portion 67 of the second umbilical 34, to locate and to extend the lateral bore section 88.

FIG. 6 is a side sectional elevation view of a portion of an alternative embodiment of the deflection member 50 of the system 10 (not shown) of the present invention positioned in a primary bore 90 using a first umbilical 134 (not shown) to cooperate with a second umbilical 34 (not shown) to extend a lateral bore section 88. The deflection member 50 may be generally centrally located relative to the surrounding bore wall 94. The deflection member 50 of FIG. 6 comprises an alternative non-circumferential deployable seal member 110 disposed to surround a lateral exit port 95 in the deflection member 50. The seal member 110 engages the bore wall 94 of the primary bore 90 to isolate the lateral bore section 88 and the lateral exit port 95.

FIG. 7 is a frontal elevation view of the alternative embodiment of the deflection member 50 of FIG. 6 illustrating the view of the deflection member 50 and the non-circumferentially deployable seal member 110 from the right side of FIG. 6. FIG. 7 illustrates lateral exit port 95 surrounded by the deployed non-circumferential seal member 110.

FIG. 8 is a top sectional view of the alternative embodiment of the deflection member 50 of FIGS. 6 and 7. The deployed non-circumferential seal member 110 is illustrated in FIG. 8 as wrapping around a portion of the deflection member 50 as it engages the bore wall 94 (not shown—see FIG. 6) of the primary bore 90 as it surrounds the lateral bore section 88 (not shown—see element 88 in FIG. 6.

FIG. 9 is a section view of an embodiment of a drill head 51 that can be connected to a leading end of the second umbilical 34 (not shown—see FIG. 5) to be positioned and controllably advanced within a lateral bore 88 by operation of the drive gears 77 (not shown—see FIG. 5) of the deflection member 50 (not shown—see FIG. 5). The drill head 51 of FIG. 9 comprises an exterior surface 59 and a drill head fluid jumper conduit 71 therein connected to the fluid conduit of the second umbilical 34 (not shown in FIG. 6—see element 49 of FIG. 4) to supply fluid to a fluid lateral 64 upon opening of a seal valve 63 to deliver fluid to a circumferentially deployable seal 54 to deploy the seal to engage and seal against the wall 94 of the bore section 88 when in the sealing mode illustrated in FIG. 9. The drill head 51 of FIG. 9 further comprises a deflation stem 60 having a seal deflation valve 61 to relieve pressure within the circumferentially deployable seal 54 to restore the deployable seal 54 to a retracted mode (not shown in FIG. 9) to disengage the wall 94 of the bore section 88. The drill head 50 further comprises a debris removal passage 66 to remove debris 81 from melted formation 19 components generated by the laser drilling process. The drill head fluid conduit 71 also supplies fluid to fluid jumper conduits 49 to deliver fluid to fluid nozzles 46 that are positioned on the drill head 51 to inject a fluid streams 75 anterior to and adjacent to laser emitting portions 45A of the drill head 51 adjacent to optical elements 45 at the leading end 56 of the drill head 51. The fluid streams 75 are directed to protect the laser emitting portions 45A from being fouled and contaminated by debris 81 being generated by the laser drilling process when laser light 52 is provided to the optical elements 45 through optical fibers 47.

FIG. 10 is a section view of an alternative embodiment of a drill head 51 of FIG. 9 comprising a transparent member 72 such as, for example, a glass or polycarbonate plate, disposed intermediate the laser emitting portion 45A of the optical elements 45 and the protective fluid stream 75. The transparent member 72 provides additional protection to the laser emitting portions 45A of the optical elements 45. The fluid streams 75 injected from the nozzles 46 provide a protective barrier for the transparent member 72 and the fluid streams 75 may impinge upon and thereby provide for debris removal for any debris that may adhere to the transparent member 72. As a result, drilling efficiency is maintained by maintaining the intensity of the laser light 52 that impinges on the wall 94 of the bore 88.

FIG. 11 is a section view of an alternative embodiment of a drill head 51 that can be used in the system of FIG. 1 having generally rigid protective barriers 73 disposed to protect the laser emitting portions 45A of the optical elements 45 of the drill head 51 when the protective barrier 73 is in the closed position illustrated in FIG. 11. The protective barriers 73 are disposed anterior to an opening or nozzle 87 (not shown in FIG. 11—see FIGS. 12-15) in a drill head structure 53 of the drill head 51 to which the protective barriers 73 may be coupled.

FIG. 12 is an enlarged view of one of the optical elements 45 of FIG. 11 having a protective barrier 73 of FIG. 11 and revealing a hinge 74 disposed intermediate the rigid protective barrier 73 and a drill head structure 85 of the drill head 51 to facilitate pivoting of the protective barrier 73 between the closed position, illustrated in FIG. 11 to protect a laser emitting portion 45A, and an open position illustrated in FIG. 13. The protective barrier 73 may be biased to the closed position using a spring element 86 and it may be coupled to the drill head structure 85 using a fastener 84. The protective barrier 73 is disposed anterior to an opening or nozzle 87 in the closed position illustrated in FIG. 12.

FIG. 13 is the protective barrier 73, the optical element 45 and the plurality of optical fibers 47 of FIG. 12 after pressurized fluid is provided through the fluid jumper conduit 49 to the opening 87 in the drill head structure 85. The fluid pressure resulting from the fluid spray 75 introduced through the opening 87 displaces the protective barrier 73 against the spring element 86 from the closed position of FIG. 12 to the open position of FIG. 13 to open a laser light pathway 52 to the laser emitting portion 45A of the optical element 45.

FIG. 14 is an alternative embodiment of the apparatus of the present invention comprising an optical element 45, a laser emitting surface 45A and a plurality of cooperating protective barrier portions 82 and 83 coupled to the drill head structure 85 using fasteners 84. The cooperating protective barrier portions 82 and 83 may comprise elastomeric elements such as, for example, temperature-resistant rubber and rubberized materials, that are biased to a relaxed, closed position shown in FIG. 14. The cooperating protective barrier portions 82 and 83 are positioned to engage one against the other to together provide a protective barrier to prevent debris from fouling or otherwise impairing emissivity of the laser emitting portion 45A. The cooperating protective barrier portions 82 and 83 cooperating protective member portions 82 and 83 are disposed adjacent to an opening 87 in the drill head structure 85.

FIG. 15 are the protective barriers 82 and 83, the optical element 45 and the plurality of optical fiber 47 of FIG. 14 after pressurized fluid is provided to the opening 87 in the drill head structure 85 to which the protective barrier portions 82 and 83 are fastened using fasteners 84. The fluid pressure resulting from the fluid spray 75 introduced through the opening 87 displaces the protective barriers portions 82 and 83 from the closed position of FIG. 14 to the open position of FIG. 15 to open a laser light pathway 52 to the laser emitting portion 45A of the optical element 45.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, a “set” may comprise a single member or a plurality of members. For example, a set of coolant injection ports or a set of gas injection ports may comprise a single coolant injection port or a single gas injection port or it may comprise a plurality of coolant injection ports or gas injection ports.

As used herein, the term “fluid” refers to either liquid or gas. It will be understood that, in embodiments of the system and/or apparatus of the present invention providing a stream of injected fluid to cool, clean and/or protect a laser emitting portion of a drill head or a protective barrier positioned adjacent to a laser emitting portion of a drill head, it is advantageous for the injected fluid to be transparent or opaque such as, for example, water, nitrogen gas, carbon dioxide gas, an inert gas, and the like. It is preferred that the fluid not be corrosive or otherwise damaging to the drill head or to the formation face exposed in the drilling process. A fluid nozzle may be a nozzle that shapes the injected stream of fluid into a broad, flattened barrier for optimal protection and coverage.

As used herein, the term “working fluid” refers to a fluid introduced into the bore system for the purpose of lubricating the bore system to facilitate the smooth insertion, positioning and removal of the apparatus comprising the drill head, for the purpose of hydrostatically opposing or balancing formation pressure to minimize the potential for well control problems due to an unwanted and unexpected influx of formation fluids into the bore.

As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components and/or groups, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The terms “preferably,” “preferred,” “prefer,” “optionally,” “may,” and similar terms are used to indicate that an item, condition or step being referred to is an optional (not required) feature of the invention.

The corresponding structures, materials, acts, and equivalents of all means or steps plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present invention has been presented for purposes of illustration and description, but it is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.

Claims

1. A system comprising:

a first umbilical having an elongate fluid conduit having a leading end and a surface end;

a fluid source coupled to a surface end of the fluid conduit of the first umbilical;

a deflection member connected to a leading end of the first umbilical and having a drive gear, a proximal end, a distal end, a laterally directed exit port intermediate the proximal and distal ends, and at least one deployable seal having at least a portion disposed intermediate the proximal end and the laterally directed exit port;

a second umbilical having a plurality of elongate optically transmitting fibers and an exterior portion having sized and shaped to be engaged and moved by the drive gear of the deflection member in a direction generally coincident with a portion of an axis of the second umbilical adjacent to the drive gear;

a laser light power generator optically coupled to a surface end of the plurality of optically transmitting fibers; and

a drill head connected to a leading end of the second umbilical and having an optical element to condition laser light received through the optically transmitting fibers of the second umbilical;

wherein the deflection member is positionable within a primary bore using the first umbilical; and

wherein the second umbilical is receivable through an umbilical pathway adjacent the drive gear and through the lateral exit port of the deflection member, and movable through the pathway by operation of the drive gear to engage and advance the exterior portion of the second umbilical to advance the drill head to extend a lateral bore formed laterally adjacent to the lateral exit port.

2. The system of claim 1 wherein the at least one deployable seal is energized to a deployed condition using fluid pressure provided through the fluid conduit.

3. The system of claim 1 wherein the gear drive is operable using fluid pressure provided through the fluid conduit to move the second umbilical along the umbilical pathway of the deflection member.

4. The system of claim 1 wherein the second umbilical exterior portion comprises a series of radially-protruding corrugations sized and shaped to engage the drive gear of the deflection member;

wherein the corrugations along the exterior portion of the second umbilical radially protrude in a plane generally perpendicular to the adjacent portion of an axis of the second umbilical.

5. The system of claim 1 wherein the second umbilical exterior portion comprises a spiraling thread sized and shaped to engage the drive gear of the deflection member;

wherein the pitch and depth of the spiraling thread matches the pitch and depth of a mating thread on the drive gear.

6. The system of claim 1 further comprising:

a seal bypass conduit of the deflection member having an inlet distal to the lateral exit port and an outlet proximal to the at least one deployable seal.

7. The system of claim 1 wherein the leading end of the fluid conduit discharges fluid provided into the surface end of the fluid conduit to a portion of the primary bore distal to the at least one deployable seal to displace fluid through the seal bypass conduit to a portion of the primary bore proximal to the at least one deployable seal to facilitate removal of laser-obstructing materials from a laser light path intermediate the laser emitting portion of the drill head and a targeted portion of a bore wall.

8. The system of claim 1, wherein the at least one deployable seal comprises:

a proximal deployable seal intermediate the proximal end and the lateral exit port of the deflection member;

a distal deployable seal on the deflection member intermediate the distal end and the lateral exit port of the deflection member;

a distal deployable seal bypass conduit of the deflection member having an inlet intermediate the lateral exit port and the distal deployable seal and an outlet distal to the distal deployable seal; and

a deflection member bypass conduit of the deflection member having a first end distal to the distal deployable seal and a second end proximal to the proximal deployable seal to equalize pressure between the portion of the primary bore intermediate the deflection member and the surface and the portion of the primary bore opposite the deflection member thereto.

9. The system of claim 8, wherein fluid displaced from the surface through the fluid conduit and from the leading end of the fluid conduit after deployment of the proximal and distal deployable seals displaces at least some material captured by deployment of the proximal and distal deployable seals in an interval intermediate the proximal and distal deployable seals through the distal deployable seal bypass to the portion of the primary bore distal to the deflection member.

10. The system of claim 8, further comprising:

a check valve disposed within the distal deployable seal bypass conduit to prevent flow from the outlet of the distal deployable seal bypass to the inlet of the distal deployable seal bypass.

11. The system of claim 1, further comprising:

an elongate control conduit of the first umbilical;

a seal deployment valve positionable in response to an activation signal provided through the control conduit between a closed position and an open position to provide fluid to the proximal deployable seal.

12. The system of claim 1, wherein the fluid provided into the surface end of the fluid conduit is one of a pressurized gas and a non-laser-obstructing liquid.

13. The system of claim 12 wherein the fluid is a pressurized gas comprising at least one of an inert gas, carbon dioxide and nitrogen.

14. The system of claim 12 wherein the fluid is a non-laser-obstructing fluid comprising at least one of ionized water, deionized water, potassium chloride, inhibited glycol and water solutions, and a dielectric fluid.

15. A drill head, comprising:

an optical element connectable to an optically transmitting fiber to emit laser light to impinge on a targeted portion of a wall of an earthen bore section; and

a fluid nozzle positioned adjacent the optical element and directed to emit a stream of fluid anterior to and proximal to a laser emitting portion of the optical element to provide a protective fluid barrier.

16. The drill head of claim 15, further comprising:

a second optical element connectable to a second optically transmitting fiber to emit laser light to impinge on the targeted portion of the wall of the bore section; and

a second fluid nozzle positioned adjacent the second optical element and directed to emit a second stream of fluid anterior to and proximal to a second laser emitting portion of the second optical element to provide a protective fluid barrier.

17. The drill head of claim 15, further comprising:

a trailing end of the drill head opposite the laser emitting portion and connectable to an optically transmitting fiber of an umbilical to provide laser light from a laser light generator at the earth's surface to the optical element and to a fluid conduit to provide a fluid from a source at the earth's surface to the fluid nozzle.

18. The drill head of claim 15, wherein the fluid nozzle is directed to impinge the fluid stream emitted therefrom onto an outer surface of the laser emitting portion of the optical element.

19. The drill head of claim 15, further comprising:

a transparent barrier disposed anterior to the laser emitting portion of the optical element of the drill head to protect the optical element from contamination by elements present within an earthen bore section.

20. The drill head of claim 19, wherein the transparent barrier comprises at least one of glass and a polycarbonate material.

21. The drill head of claim 19, further comprising:

a fluid jumper conduit within the drill head and having a first portion connectable to a leading end of a fluid conduit to provide a stream of fluid flow through the fluid nozzle and onto the transparent barrier to remove heat generated by laser light emitted through the transparent barrier.

22. The drill head of claim 21, further comprising:

an outlet from the fluid jumper conduit connected to the fluid nozzle;

wherein the fluid nozzle provides a fluid barrier to protect the transparent barrier.