Laser milling and removal tool and methods

Systems and methods for cutting objects within a subterranean well include a laser system having a laser drilling head located at a terminal downhole end of a laser tool body directing a head laser beam in a direction downhole. A laser scanner assembly located within the laser tool body has a scanner head directing a scanner laser beam and can move both axially along a length of the laser tool body and rotate around a central axis of the laser tool body. A laser cutter assembly located within the laser tool body has a cutter head directing a cutter laser beam and can rotate around the central axis of the laser tool body. A cable bundle formed of a plurality of fiber optic cables extends from an uphole end of the laser tool body to each of the laser drilling head, the laser scanner assembly, and the laser cutter assembly.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

The disclosure relates generally to drilling and completion of a subterranean well, and more particularly to tools and methods related to the use of lasers in downhole applications.

2. Description of the Related Art

During conventional drilling of a subterranean well, a mechanical drill bit is used to drill into the formation in sections and the well section can then be cased with steel pipe. The steel pipes of the casing can be cemented into place. The creation of holes or windows in the casing after the casing has been installed in the wellbore can be achieved with mechanical tools such as milling tools which grind through the metal tubular members. Milling the casing can involve cutting a window through the side of the casing or to remove a continuous section of the casing so that the wellbore may be deviated from the original well through the window or section removed.

In addition, there may be times during the drilling, completion, or operation of the subterranean well that items are lost within the wellbore. Such items are commonly called fish or junk. The items can be, for example, junk metal, tools, parts or pieces of drill pipe or drill collars, drilling components, or other components used within the subterranean well. The item that is accidentally dropped or left within the wellbore can fall to the bottom of the wellbore or become jammed within the wellbore, blocking the wellbore or damaging the tubular members. Such fish can currently be mechanically removed with a milling tool, such as a tool that grinds the fish into smaller pieces to be removed from the wellbore. As an example, a fluid flow within the wellbore can remove the milled material from the wellbore.

SUMMARY OF THE DISCLOSURE

Mechanical means to mill objects in a wellbore and create holes and windows in casing can be time consuming and inaccurate. Embodiments of this disclosure provide systems and methods for removing a target material in the wellbore or grinding away a target portion of the casing by cutting the target in small parts. The tool operates in three actions: circular cutting; using side rotational lenses; longitudinal cutting using scanner optics; and laser head drilling to remove stuck material in the well bore. Systems and method of this disclosure utilize a laser that can provide precise and reliable material removal.

In an embodiment of this disclosure, a laser system for cutting objects within a subterranean well having a longitudinal axis includes a laser drilling head located at a terminal downhole end of a laser tool body. The laser drilling head is operable to direct a head laser beam in a direction downhole of the laser tool body. A laser scanner assembly is located within the laser tool body uphole of the laser drilling head. The laser scanner assembly has a scanner head operable to direct a scanner laser beam and to move both axially along a length of the laser tool body and rotate around a central axis of the laser tool body. A laser cutter assembly is located within the laser tool body uphole of the laser drilling head. The laser cutter assembly has a cutter head operable to direct a cutter laser beam and to rotate around the central axis of the laser tool body. A cable bundle is formed of a plurality of fiber optic cables extending from an uphole end of the laser tool body to each of the laser drilling head, the laser scanner assembly, and the laser cutter assembly.

In alternate embodiments, the laser scanner assembly can include an axial support, where the scanner head is moveable along the axial support. The scanner head can be rotatable relative to the axial support in an axial direction. The laser scanner assembly can be operable to direct the scanner laser beam in a zigzag pattern along an internal surface of the subterranean well. The laser cutter assembly can include a support ring and one of the plurality of fiber optic cables can extend from the cable bundle to the support ring.

In other alternate embodiments, the laser cutter assembly can include a cutter lens operable to direct the cutter laser beam from one of the plurality of fiber optic cables. The laser cutter assembly can be operable to direct the cutter laser beam in a circumferential pattern along an internal surface of the subterranean well. The laser cutter assembly can be operable to direct the cutter laser beam in a helical pattern along an internal surface of the subterranean well as the laser tool body is moved longitudinally within the wellbore.

In yet other alternate embodiments, the system can further include an orientation member, the orientation member operable to confirm the orientation of the laser system within the subterranean well. The system can alternately include a logging tool, the logging tool operable to confirm the axial location of the laser tool body within the subterranean well. The system can alternately include a joint located uphole of the laser drilling head, and downhole of both the laser scanner assembly and the laser cutter assembly. The system can further include a packer located radially exterior of the laser tool body, the packer selectively extendable to position the laser tool body within the subterranean well.

In an alternate embodiment of this disclosure, a method for cutting objects within a subterranean well having a longitudinal axis includes lowering a laser system into the subterranean well. The laser system has a laser drilling head located at a terminal downhole end of a laser tool body. A laser scanner assembly is located within the laser tool body uphole of the laser drilling head. A laser cutter assembly is located within the laser tool body uphole of the laser drilling head. A cable bundle is formed of a plurality of fiber optic cables extending from an uphole end of the laser tool body to each of the laser drilling head, the laser scanner assembly, and the laser cutter assembly. The method further includes directing a head laser beam in a direction downhole of the laser tool body with the laser drilling head. A scanner laser beam is directed with a scanner head of the laser scanner assembly, the laser scanner assembly moveable both axially along a length of the laser tool body and rotationally around a central axis of the laser tool body. A cutter laser beam is directed with a cutter head of the laser cutter assembly, the laser cutter assembly rotatable around the central axis of the laser tool body.

In alternate embodiments, the laser scanner assembly can include an axial support, and the method can further include moving the scanner head along the axial support. The scanner head can rotate relative to the axial support in an axial direction. The laser scanner assembly can direct the scanner laser bean in a zigzag pattern along an internal surface of the subterranean well.

In other alternate embodiments, the laser cutter assembly includes a support ring, and the method can further include extending one of the plurality of fiber optic cables from the cable bundle, to the support ring. The laser cutter assembly can include a cutter lens, and the method can further include directing the cutter laser beam from one of the plurality of fiber optic cables with the cutter lens. The laser cutter assembly can direct the cutter laser beam in a circumferential pattern along an internal surface of the subterranean well. Alternately, the laser cutter assembly can direct the cutter laser beam in a helical pattern along an internal surface of the subterranean well as the laser tool body is moved longitudinally within the wellbore.

In yet other alternate embodiments, the laser system can further include an orientation member, and the method can further include confirming the orientation of the laser system within the subterranean well with the orientation member. The laser system can further include a logging tool, and the method can further include confirming the axial location of the laser tool body within the subterranean well with the logging tool. The laser system can further include a joint located uphole of the laser drilling head, and downhole of both the laser scanner assembly and the laser cutter assembly. The laser system can further include a packer located radially exterior of the laser tool body, and the method can further include extending the packer to position the laser tool body within the subterranean well.

DETAILED DESCRIPTION OF THE DISCLOSURE

The disclosure refers to particular features, including process or method steps. Those of skill in the art understand that the disclosure is not limited to or by the description of embodiments given in the specification. The subject matter of this disclosure is not restricted except only in the spirit of the specification and appended Claims.

Those of skill in the art also understand that the terminology used for describing particular embodiments does not limit the scope or breadth of the embodiments of the disclosure. In interpreting the specification and appended Claims, all terms should be interpreted in the broadest possible manner consistent with the context of each term. All technical and scientific terms used in the specification and appended Claims have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs unless defined otherwise.

As used in the Specification and appended Claims, the singular forms “a”, “an”, and “the” include plural references unless the context clearly indicates otherwise.

As used, the words “comprise,” “has,” “includes”, and all other grammatical variations are each intended to have an open, non-limiting meaning that does not exclude additional elements, components or steps. Embodiments of the present disclosure may suitably “comprise”, “consist” or “consist essentially of” the limiting features disclosed, and may be practiced in the absence of a limiting feature not disclosed. For example, it can be recognized by those skilled in the art that certain steps can be combined into a single step.

Where a range of values is provided in the Specification or in the appended Claims, it is understood that the interval encompasses each intervening value between the upper limit and the lower limit as well as the upper limit and the lower limit. The disclosure encompasses and bounds smaller ranges of the interval subject to any specific exclusion provided.

Where reference is made in the specification and appended Claims to a method comprising two or more defined steps, the defined steps can be carried out in any order or simultaneously except where the context excludes that possibility.

Referring toFIG.1, subterranean well10can have wellbore12that extends from an earth's surface14. Subterranean well10can be an offshore well or a land based well and can be a well associated with hydrocarbon development operations, such as, for example, a hydrocarbon production well, an injection well, or a water well. Wellbore12can be drilled from surface14and into and through various subterranean formations. Subterranean well10can have a longitudinal axis, Ax. In the example embodiment ofFIG.1, subterranean well10is shown as extending generally vertically from surface14. In alternate embodiments, subterranean well10can have a wellbore12that is not generally vertical relative to surface14, such as an inclined, deviation, horizontal wellbore.

Casing16can line an inner diameter surface of wellbore12. Casing16can be formed of a series of tubular pipe joints that are secured end to end. Casing16can be a tubular member that has a bore.

There may be times during the development or operation of subterranean well10that a component18is lost within wellbore12. Such components18are commonly called fish or junk. Component18can be, for example, junk metal, tools, parts or pieces of drill pipe or drill collars, drilling components, or other components used within the subterranean well10. Component18that is accidentally dropped or left within wellbore12can fall to the bottom of wellbore12.

There may alternately be times during the development or operation of subterranean well10that there are blockages or obstructions within wellbore12, or damage to tubular members or equipment within wellbore12. The obstructions can be caused, for example, by a component18being stuck or jammed within wellbore12. Looking atFIG.1, component18is shown generically as an item that has been lost within wellbore12, as an item that is blocking or obstructing wellbore12, or as a damaged feature of wellbore12.

In other alternate times, an operator may wish to cut through casing16or another tubular member within wellbore12. As an example, the operator may want to cut a window through the side of casing16or to remove a continuous section of casing16so that the wellbore may be deviated from the original well through the window or section removed.

Laser system22can be used to cut component18or a portion of casing16into pieces of a size that can be removed from wellbore12. Looking atFIGS.2-3, laser system22includes laser tool body24. Laser tool body24is a generally tubular shaped member. Laser tool body24surrounds and contains features of the laser tool body24. Laser tool body24can be secured to a delivery member26(FIG.1), such as a wireline, e-line, drill string, or other tubular member.

Looking atFIG.3, laser drilling head28is located at a terminal downhole end of laser tool body24. Orientation member30is located uphole of laser drilling head28. Logging tool32is also positioned uphole of laser drilling head28. Orientation member30and logging tool32are also located within laser tool body24. Laser drilling head28, orientation member30and logging tool32together form a downhole assembly of laser system22. Joint34is secured to an uphole end of the downhole assembly of laser system22, securing the downhole assembly of laser system22to an uphole assembly of laser system22.

Uphole assembly of laser system22includes laser scanner assembly36and laser cutter assembly38. Each of laser scanner assembly36and laser cutter assembly38are also located within laser tool body24. Each of laser scanner assembly36and laser cutter assembly38are also located within laser tool body24. Laser drilling head28, laser system22, and laser cutter assembly38are secured in line. Cable bundle40extends from within laser tool body24and out an uphole end of laser tool body24. Cable bundle40is formed of a plurality of fiber optic cables that extend from an uphole end of laser tool body24to each of laser drilling head28, laser scanner assembly36, and laser cutter assembly38.

Looking atFIG.4, laser drilling head28can direct head laser beam42beam in a direction downhole of the laser tool body. Head laser beam42can be used to penetrate into component18that is stuck in wellbore12. Laser energy is generated by the generator at the surface by laser generator44(FIG.1) and a primary laser beam is delivered by way of cable bundle40to laser system22. Laser generator44can generate a high powered laser beam that can drill into and through different materials including steel, alloy, cement and rocks. Because laser generator44can generate a laser beam that can cut and drill through steel, alloy, cement or rocks, embodiments of this application can therefore successfully cut into and through such materials as well as other materials having a similar range of stress or strength.

Optics of laser drilling head28can be used to direct the primary laser beam to form head laser beam42and direct head laser beam42towards component18. The primary laser beam used to form head laser beam42can have a power of at least 5 kW and be a continuous laser beams that is delivered by fiber optics.

Orientation member30can confirm the orientation of laser system22within subterranean well10. Orientation member30can, for example, determine the alignment of laser system22relative to a target location. Such alignment determination may include an axial distance of laser system22from a target or a relative distance or radial positioning of laser drilling head28, laser scanner assembly36, or laser cutter assembly38from a target. The target may be, for example, a component18or a location along casing16where an operator desires to remove casing material. The orientation of laser system22can be accomplished by presetting laser system22on the surface or by manipulating laser system22downhole. The orientation of laser system22can be adjusted by an electric motor that can rotate laser system22in the direction desired.

Logging tool32can be used to gather information relating to the position of laser tool body24within subterranean well10. As an example, logging tool32can gather information as laser system22travels within subterranean well10that can be used to determine the axial location of laser tool body24within subterranean well10. Logging tool32can be a sonic, resistivity, gamma ray, density, or other known type of logging instrument.

Joint34is located uphole of laser drilling head28, and downhole of both laser scanner assembly36and laser cutter assembly38. In an example embodiment, joint34is secured between logging tool32and laser scanner assembly36. Joint34can be used when servicing laser system22. As an example, laser system22can be disassembled at joint34to isolate a portion of laser system22to be repaired or replaced.

Laser scanner assembly36is located uphole of both laser drilling head and joint34. Looking atFIG.5, laser scanner assembly36includes scanner head46. Scanner head46can direct scanner laser beam48.

Scanner head46can receive a primary laser beam that is delivered by way of cable bundle40to laser scanner assembly36. Scanner primary laser beam50can extend in a direction that is generally parallel to central axis52(FIG.1) of laser tool body24. Scanner head46can be positioned to change the direction of scanner primary laser beam50so that the scanner laser beam48is directed radially outward.

As scanner head46directs scanner laser beam48. Scanner head46is a reflector that can move in a circular direction. Scanner head46can also move either axially along a length of laser tool body24or rotate around central axis52of laser tool body24. As shown inFIG.5, in an example embodiment, laser scanner assembly36includes axial support54. Scanner head46can move axially along a length of laser tool body24by moving along axial support54.

Axial support54can be an elongated member extending in a downhole direction from a support plate55of laser scanner assembly36. Support plate55can stabilize laser scanner assembly36, prevent vibration of laser scanner assembly36to ensure a quality consistent and stable laser beam. Support plate55can be a ring or disk shaped member centered around central axis52. Support plate55can include optics that release the size, shape, and focus scanner primary laser beam50from scanner fiber optic cables62.

Scanner head46indirectly engages axial support54through brace member56and ring member58. Ring member58circumscribes axial support54and can slide axially along axial support45. Brace member56extends from ring member58to scanner head46. Scanner head46can rotate relative to axial support54in an axial direction. That is, scanner head46can pivot in a manner that causes the scanner laser beam to be directed from an uphole direction to a downhole direction along an axially oriented plane. Both the movement of scanner head46along axial support54and the rotation of scanner head46in the axial direction will allow laser scanner assembly36to make axial cuts into a component18, casing16, or other internal surface of subterranean well10.

Laser scanner assembly36further includes scanner rotation coupling60. Rotation coupling60provides for rotation of scanner head46about central axis52of laser tool body24. Scanner head46can rotate in either or both of a clockwise or counter clockwise direction around central axis52.

InFIG.5, two scanner heads46are shown. In alternate embodiments, there may be one scanner head46or more than two scanner heads46. The number of scanner heads46can be determined by the volume of material to be milled, and the depth to which the material is to be cut.

Cable bundle40contains a plurality of fiber optic cables. Each scanner head46will be delivered a separate scanner primary laser beam50by way of one of the scanner fiber optic cables62from the plurality of fiber optic cables of cable bundle40. Scanner fiber optic cables62can extend to the support plate of laser scanner assembly36. Other of the fiber optic cables will continue past laser scanner assembly36to reach laser drilling head28. Such other fiber optic cables are not shown inFIG.5.

As scanner head46is rotated about central axis52of laser tool body24, scanner head46can also move axially along axial support54, or can rotate in the axial direction, or both. Such rotation and axial movement will allow laser scanner assembly36to make zigzag cuts into a component18, casing16, or other internal surface of subterranean well10.

Looking atFIG.4, laser cutter assembly38is located uphole of laser drilling head28. Looking atFIG.6, laser cutter assembly includes cutter head64. In the embodiment ofFIG.6, there are four cutter heads64. In alternate embodiments there could be one to three cutter heads64, or more than four cutter heads64. The number of cutter heads64can be determined by the volume of material to be milled, and the depth to which the material is to be cut.

Cutter head64directs cutter laser beam66. Cutter head64can receive a primary laser beam that is delivered by way of one of the plurality of fiber optic cables of cable bundle40to laser cutter assembly38. The primary laser beam can provide a beam that can be split between head laser beam42and cutter laser beam66. Alternately, the primary laser beam can sequentially generate head laser beam42and cutter laser beam66.

Each cutter head64will be delivered a separate cutter primary laser beam68. Cutter primary laser beam68can extend in a direction that is generally parallel to central axis52(FIG.1) of laser tool body24. Laser cutter assembly38includes cutter lens74. Cutter lens74s positioned to change the direction of cutter primary laser beam68so that cutter laser beam66is directed radially outward.

Laser cutter assembly38includes support ring72. Support ring72is a ring shaped structural member located at a downhole end of fiber optic cable70within laser tool body24and centered around central axis52. Support ring72can stabilize laser cutter assembly38, prevent vibration of laser cutter assembly38to ensure a quality consistent and stable laser beam.

Cutter fiber optic cable70is one of the plurality of fiber optic cables of cable bundle40. Cutter fiber optic cable70extends to support ring72. Other of the fiber optic cables will continue past laser cutter assembly38to reach laser drilling head28. Such other fiber optic cables are not shown inFIG.6.

Laser cutter assembly38further includes cutter lens ring80. Cutter lens ring80is a ring shaped structural member within laser tool body24and centered around central axis52. Cutter optics82are mounted on cutter lens ring80. Cutter optics82are used to shape and size primary laser beam68. Cutter lens ring80is mounted on rails84. Cutter lens ring80can slide along rails84to size, shape, and focus primary laser beam68. The optics for laser cutter assembly38are designed to operate with a high powered laser beam with minimum power loss, no reflection, and no heating. As an example, fused quartz can be used to form the optics for laser cutter assembly38.

Laser cutter assembly38further includes cutter rotation coupling76. Cutter rotation coupling76provides for rotation of cutter head64about central axis52of laser tool body24. Cutter head64can rotate in either or both of a clockwise or counter clockwise direction around central axis52.

As cutter head64is rotated about central axis52of laser tool body24, cutter head64will direct cutter laser beam66to form cuts in a circumferential pattern along a component18, casing16, or other internal surface of subterranean well10. If laser system22is being moved longitudinally within wellbore12as cutter head64is rotated about central axis52of laser tool body24, cutter head64will direct cutter laser beam66to form cuts in a helical pattern along a component18, casing16, or other internal surface of subterranean well10.

In certain embodiments, as shown inFIG.4, packer78is located radially exterior of laser tool body24. Packer78is selectively extendable to position and stabilize laser tool body24within the subterranean well10. Packer78can be used to stabilize laser tool body24while laser tool body24is stationary or while laser tool body24is moving axially within wellbore12. Packer78can be any type of packer capable of expanding downhole. Multiple packers78can be arranged at regular intervals along the length of the laser tool body24or delivery member26, or along both laser tool body24and delivery member26. The total number of packers78can be determined by the length of wellbore12. In at least one embodiment, packer78is expanded by a means controlled at the surface.

In an example of operation, when cutting of a component18, casing16, or other internal surface of subterranean well10is desired, laser system22can be lowered into subterranean well10on delivery member26, as shown inFIG.1. Depending on the target to be cut and removed from wellbore12, one or more of laser drilling head28, laser scanner assembly36, and laser cutter assembly38can be used to cut the target.

Looking atFIG.4, logging tool32can be used to determine when laser drilling head28of laser system22is approaching component18. Orientation member30can be used to ensure that laser drilling head28of laser system22is properly oriented within wellbore12relative to component18. Laser drilling head28can then direct head laser beam42beam towards component18so that component18is cut, chipped, melted, or vaporized by head laser beam42. Laser drilling head28can continue to direct head laser beam28towards component18until any remaining pieces of component18are sufficiently small to be flushed out of wellbore12by fluid circulation within wellbore12.

In alternate embodiments, one or both of laser scanner assembly36and laser cutter assembly38can be used to cut casing16. Logging tool32can be used to determine when laser scanner assembly36of laser system22is approaching the target region of casing16. Orientation member30can be used to ensure that laser scanner assembly36of laser system22is properly oriented within wellbore12relative to target region along casing16.

Laser scanner assembly36can first be used to direct scanner laser beam48radially outwards. Movement of scanner head46along axial support54or the rotation of scanner head46in the axial direction, or both movement of scanner head46along axial support54and the rotation of scanner head46in the axial direction, will allow laser scanner assembly36to make axial cuts into a component18, casing16, or other internal surface of subterranean well10.

Alternately, scanner head46can be rotated about central axis52of laser tool body24, while scanner head46also moves axially along axial support54, or rotates in the axial direction, or both. Such combined rotation and axial movement will allow laser scanner assembly36to make zigzag cuts into a component18, casing16, or other internal surface of subterranean well10. A schematic representation of an example zigzag pattern86is shown inFIG.7A.FIG.7Bis a schematic representation of such zigzag pattern86cut into casing16. Zigzag pattern86can be cut into casing16as laser scanner assembly36is moved axially within wellbore12so that zigzag pattern86spirals around an inner diameter surface of casing16.

Looking atFIG.4, in alternate embodiments, logging tool32can be used to determine when laser cutter assembly38of laser system22is approaching the target region of casing16. Orientation member30can be used to ensure that laser cutter assembly38of laser system22is properly oriented within wellbore12relative to target region along casing16.

Laser cutter assembly38can be used in conjunction with or separately from laser scanner assembly36. As cutter head64is rotated about central axis52of laser tool body24, cutter head64will direct cutter laser beam66to form cuts in a circumferential pattern along a component18, casing16, or other internal surface of subterranean well10. If laser system22is moved longitudinally within wellbore12as cutter head64is rotated about central axis52of laser tool body24, cutter head64will direct cutter laser beam66to form cuts in a helical pattern along a component18, casing16, or other internal surface of subterranean well10.

A schematic representation of an example helical pattern88is shown inFIG.8A.FIG.8Bis a schematic representation of such helical pattern88cut into casing16. Helical pattern88can be cut into casing16as laser cutter assembly38is moved axially within wellbore12so that helical pattern88spirals around an inner diameter surface of casing16.

Laser cutter assembly38can makes cuts in casing16in the same region that was previous cut by laser scanner assembly. The combination of helical pattern88being cut over zigzag pattern86will result in the target section of casing16being cut into small pieces. Looking atFIG.9Aa schematic representation of example helical pattern88superimposed on zigzag pattern is shown.FIG.9Bis a schematic representation of such helical pattern88superimposed on zigzag pattern and cut into casing16. The resulting pieces are sufficiently small to be flushed out of wellbore12by fluid circulation within wellbore12.

Embodiments of this disclosure therefore provide systems and method for milling, cutting and drilling materials in a subterranean well. Laser energy is generated by a generator at the surface and the beam is delivered by way of fiber optics cable to the tool, the beam is manipulated at the laser tool which combines mechanical and optical parts to reconfigure the beam in any shape and size. The combination of the mechanical and optics parts and able to create different laser beam shapes and patterns, utilizing this properties, the proposed solution to mill, cut and drill the pipe and stuck objects by combing these patterns to breakdown the material is very small pieces and remove them from the wellbore.