This invention relates to the field of pipe handling systems for drilling rigs and in particular to a portable pipe handling system including a pipe handler for tripping in and out of the well string, and for the make up and delivery of pipe stands on a portable pipe handling system which is positionable adjacent a drilling rig mast and substructure for delivery of the pipe stand to a top drive or the rig floor.
Conventionally, drilling tubulars are transported in single lengths. A single length of tubular is for example 31 feet in length. Tubulars can however be used on a top drive-equipped drilling rig in triple lengths, that is, in lengths which are for example 93 feet long. Such combined lengths of tubulars are referred to as pipe stands. For efficiency during drilling, it is desirable to combine the single tubulars into for example triple length pipe stands off the critical path of the operation of the drilling rig so to not interfere with the drilling operation.
Moving pipe stands onto and off from the critical path of the drilling operation for tripping operations is often done with a robotic or at least power-assisted manipulating device, which at least in part replaces, or mechanizes or automates the manual function of members of the drilling rig crew referred to as derrickmen.
An associated part of the tripping operation is placing made up pipe stands into a storage rack mounted on the derrick mast. These racks are sometimes referred to as racking boards. Pipe stands must be manipulated into, and retrieved from the racking board during tripping operations. Numerous pipe racking systems have been developed and are available in the industry. For example, applicant is aware of pipe racking systems which are commercially available from National Oilfield Varco also referred to as NOV, Aker and Weatherford. All of these pipe racking systems are highly integrated, for example, integrated structurally, hydraulically, and/or electrically, into the drilling rig. Most of these are practical only for offshore applications.
Drilling rigs for use on land, referred to as land rigs, have additional mobility requirements, cost constraints and service access challenges. Consequently, in applicant's view, it is desirable to have a racking system for land rigs which is: (a) independently transportable, that is, transportable independently of the land rig; (b) relatively fast and easy to rig up and down; (c) applicable to a wide range of land rigs without significant customization or interface design, to enable manufacturing economies of scale and economy/flexibility of application, for example, temporary use, rental, shared use among rigs, provision as a separately contracted rig accessory; and (d) relatively easily and safely serviceable.
Numerous systems of which applicant is aware have been used for offline building of pipe stands, referred to as stand-building, wherein the stand-building is done either horizontally, or vertically, or for example built vertically in a mousehole. However, in the prior art stand-builders the following limitations or drawbacks are encountered: some stand-builders can only assemble doubles, that is, pipe stands having only two tubulars, some stand-builders require an unconventionally deep mousehole on every well, and also, mousehole-based stand-building systems require manual handling operations within close proximity of the rotating pipe at well center which is a safety concern; and some stand-builders cannot pass the assembled pipe stand directly to the top drive elevators, requiring an additional pipe stand transfer step.
It is an object to provide an improved pipe handling system which lends itself well to assisting land-based oil and gas drilling rigs. For example conventional rigs may not have been originally supplied with pipe handling equipment. Thus such rigs may not be well adapted for tripping and for pipe stand make up, delivery of pipe stands into the pipe racking board, for assisting in the initial make up, break down and re-make up of new pipes which must have their threaded tool joints spun, initially torqued, released then re-torqued, and for delivery of pipe stands to the top drive elevators. Thus a portable pipe handling system would be useful in such cases for example during start up, where the racking board may be filled with pipe stands ready to use and supported vertically in the racking board, where each pipe stand has been made up and delivered by the portable pipe handling system according to one aspect of the present invention, and thereafter, during so-called tripping-in or tripping-out of the pipe string the pipe stands are efficiently tripped in and out of the well. Pipe stands may be efficiently made up and delivered to the top drive or removed from the top drive and broken down or moved in and out from the racking board to and from well center using the present invention lending flexibility, efficiency and safety to the operation of the rig. In this invention, portability advantageously includes a minimal interface between the rig and the portable pipe handling system, where minimizing the interface includes minimizing mechanical, electrical and hydraulic interface, in other words where the pipe handling system is largely independent of the rig.
In summary, the portable pipe handling system according to one aspect of the present invention may be characterized as including for use in conjunction with a drilling rig having a drilling mast aligned with a well center and mounted atop a rig sub-structure, a support structure adapted to support a pipe stand along an inclined pipe stand building axis, wherein the pipe stand building axis is inclined so that a pipe stand translation trajectory which is substantially co-axial with the pipe stand building axis intersects a hand-off window between the drilling mast and the pipe stand building axis.
The system may also include a base coupled to the support structure, and a tubular handler cooperating with the base and the support structure, wherein the tubular handler is adapted to deliver a tubular between the base and the stand building axis. The support structure may include a pipe stand joint thread rotator such as a wrench, tong or spinner, and a pipe stand holder such as an elevator, roller, slip, clamp or guide, on the pipe stand building axis, wherein the pipe stand holder cooperates with the support structure so that the pipe stand is held stationary on the pipe stand building axis or is translated along the pipe stand translation trajectory.
In one embodiment, the support structure includes a pipe handler mast, for example where the mast is on the stand building axis. The base may include a catwalk. The mast may be pivotally coupled to the catwalk so that the inclination of the pipe stand building axis is adjustable.
The tubular handler may include a tubular transport arm having a leading end and an opposite trailing end, wherein the tubular transport arm is translatable along the base and along the pipe stand building axis, for example, along the pipe handler mast. An actuator may be provided which cooperates between the base and the support structure to actuate the translation of the tubular transport arm along at least the base.
Advantageously, during the translation of the tubular transport arm the tubular transport arm is rotated in a substantially vertical plane containing the base and the pipe handler mast between a substantially horizontal position substantially parallel to the base and an inclined position substantially parallel to and adjacent the pipe handler mast.
Further advantageously, an anti-sway structure is mounted to the support structure and adapted for stabilizing the support structure to the drilling mast or rig sub-structure. Preferably the anti-sway structure is adapted to substantially only react lateral side loading on the support structure, lateral relative to the support structure, to the drilling mast or rig sub-structure, that is, substantially without reacting vertical loading into the drilling mast or rig sub-structure.
In a preferred embodiment a robotic pipe handler is mounted to an upper end of the support structure, for example to the upper end of the pipe handler mast, to transfer the pipe stand between at least the pipe stand building axis and substantially the well center. The robotic pipe handler reacts substantially all vertical loading thereon to the support structure.
In one embodiment the base includes a catwalk and the tubular transport arm comprises a leading arm which includes the leading edge, and a trolley which includes the trailing edge. In a preferred embodiment the arm is pivotally coupled to the trolley. The leading arm supports one of the tubulars as the rotation of the tubular transport arm rotates only the leading arm, and trolley remains substantially horizontal on the catwalk, and is drawn along the catwalk during the rotation of the leading arm. Again in the preferred embodiment the leading arm is selectively rigidly coupled to the trolley by selective disabling of the pivotal coupling between the leading arm and the trolley so that, when rigidly coupled, the leading arm is substantially co-linear with the trolley during the rotation of the tubular transport arm so that longer objects such as casing may be delivered between the stand building axis and the base.
Advantageously the tubular transport arm further comprises a skate for pushing a tubular towards the leading edge and onto the leading arm ahead of the trolley. The pivotal coupling may be a hinge. The skate may cross the hinge so as to translate along both the trolley and the leading arm.
In one embodiment the mast is pivotable down onto the catwalk for transport.
Advantageously the robotic pipe handler is adapted for tripping pipe stands. The system may further include or be adapted to cooperate with a top drive retractor cooperating with the top drive in the drilling rig to retract the top drive from well center, and wherein the robotic pipe handler and the top drive when in the retracted position cooperate during the tripping to increase tripping speed.
The present invention is also intended to include methods implementing use of the system described herein. For example, and without intending to limit the methods according to the various aspects of the present invention, one pipe handling method may be characterized as including:
By way of further example, the method according to another aspect of the invention may include providing a base for the support structure, positioning the base adjacent the sub-structure, delivering one or more tubulars between the base and the pipe stand building axis for make-up or break-down of a corresponding pipe stand along the pipe stand building axis, and delivering the pipe stand or the tubulars therefrom to a selected position chosen from: the hand-off window, the well center, or the base.
The method may further include providing a robotic pipe handler mounted on the support structure at an upper end of the pipe stand building axis, and manipulating the robotic arm so as to move a pipe stand between any two of the following positions: the well center, the hand-off window, the racking board, the pipe stand building axis. Where the drilling rig includes a top drive retractor, the method may further include retracting the top drive and tripping a pipe stand using the robotic pipe handler so that the tong and robotic arm functions happen simultaneously as the top drive is travelling empty.
a and 27 onward depict an alternative embodiment wherein a pair of driven “v” rollers are mounted on the stand builder mast above the wrench.
a, 31b, 31c and 31d depict, respectively, a top drive in its extended working position aligned with well center, with the exception of
As seen in the accompanying figures wherein like reference numerals denote corresponding parts in each view, as depicted in
As used herein, catwalk may also be referred to as included within the meaning of the word “base”. Use of the word base herein is intended to refer to a structure upon or to which the pipe handler mast is coupled. Base may but does not necessarily include a catwalk, storage facilities for tubulars, whether horizontally stored or not, and facilities for providing tubulars to and from storage, and to and from the pipe handler mast. Further, use of the phrase pipe handler mast may also be referred to as included within the meaning of the phrase “pipe handler support structure” or “support structure”. Those phrases are intended to refer to a structure which is coupled to the base and which supports a pipe stand building axis as hereinafter described and associated apparatus to make-up or to break-down, or both, a pipe stand of tubulars when the pipe stand is positioned, held, guided, and/or conveyed along the pipe stand building axis. The pipe handler mast is merely intended to be one example of structures which would work for this intended purpose as would be known to one skilled in the art. For example an alternative support structure may include a vertical mast, that is, not on the pipe stand building axis, and outstanding arm arrangement for supporting a pipe stand along the inclined pipe stand building axis. The support structure would support working elements such as apparatus for relative counter-rotation of the threads in a pipe stand joint so as to spin, make-up or break-down a pipe stand, or assist in doing so, which may include, without limitation, wrenches or tongs, or spinners, as would be known to one skilled in the art, and which, without intending to be limiting, are collectively referred to herein as pipe stand joint thread rotators. At least one pipe stand or tubular handler would also be supported on the support structure, which, without intending to be limiting, is intended to include not only the tubular transport arm and robotic arm described below, but also other apparatus for lifting, winching, hoisting, guiding, or otherwise positioning by mechanical or electromechanical or other assisted means the positioning of pipe stands and tubulars, as would be known to one skilled in the art. The handler or handlers would be assisted by pipe stand holders which guide, hold in place on, and may advantageously also selectively elevate or convey the pipe stand or tubulars along the pipe stand building axis. Examples of such pipe stand holders, as the term is intended to be broadly interpreted, include the various elevators and/or rollers, slips and clamps, skates and the like described below which guide, hold and convey tubulars and the pipe stand.
Returning now to the example of the illustrated embodiments, pipe handler mast 12 is positioned adjacent a drilling rig mast 14 and corresponding substructure 16. A tubular transport arm 18 delivers tubulars 20 from catwalk 10 to pipe handler mast 12. A wrench 22 and pipe stand elevators 24, for making up multiple tubular pipe stands within pipe stand handler mast 12, are mounted to mast 12. Mast 12 is positioned and aligned for delivery of the top of the pipe stand 8 to top drive 26 mounted in drilling rig mast 14, and in particular for delivery of the pipe stand to top drive elevators 26a.
Tubulars 20 are delivered in a conventional fashion onto catwalk 10 from conventional pipe racks 28 so as to rest a tubular from the rack into a longitudinally extending centre channel 10a of the catwalk.
Tubular transport trolley 30 is mounted within centre channel 10a of catwalk 10 for translation longitudinally along the catwalk. Tubular transport arm 18 (also labelled in
Although the sequence is also better described below with reference to
Once the triple-tubular pipe stand has been made up, the pipe stand elevators extend the pipe stand upwardly in direction A along trajectory B so as to position the uppermost end of the pipe stand 8, that is, so as to position end 20a of the first tubular 20 within the pick up range of the articulated elevators 26a on top drive 26. Thus in the example illustrated in
In one embodiment, and, again, dependent on the location and size of the effective hand-off window, the inclination angle {acute over (α)}, (alpha), that is, the pipe stand inclination angle alpha measured from the vertical, may, without intending to be limiting, advantageously be in the order of 5 to 25 degrees. The range of angle {acute over (α)}, (alpha) angles which would work for handing off a pipe stand in the hand-off window would for example depend on whether space was required between the rig substructure 16 and the pipe stand building mast 12 for the positioning of the blowout preventers, in which case angle {acute over (α)}, (alpha) may be greater to provide for greater spacing. In instances where mast 12 may be substantially abutted against, or inset into, substructure 16, then angle {acute over (α)}, (alpha) may be less so long as trajectory B guides pipe stand 8 in direction A along trajectory B so as to intersect the upper end of the pipe stand with hand-off window 100 for top drive elevators 26a.
The catwalk 10 and associated equipment will now be discussed in more detail. Preferably pipe racks 28 are positioned on opposite sides of catwalk 10. Pipe racks 28 are inclined so that tubulars 20 stored on top of pipe racks will roll downwardly towards catwalk 10 whereupon they may be indexed from behind stops 28a onto trolley 30 by the upwardly actuated inclination of lateral transfers 36 which elevate a tubular 20, one at a time, over stops 28a so that the singulated tubular rolls down lateral transfer 36 and onto trolley 30 which has been positioned adjacent the inboard or centremost ends of lateral transfers 36. This is done while making up pipe stands. When the opposite is being done; namely, pipe stands are being broken down and their tubulars are being returned to the pipe racks, then arm 18 and trolley 30 are used to return tubulars to the horizontal, adjacent the pipe racks. Kickers 50 are actuated so as to extend upwardly from under the upper surfaces of arm 18 and trolley 30. Kickers 50 engage upwardly through, so as to move laterally across, slots 18a or 30a depending on whether they mounted on arm 18 or trolley 30 respectively. When actuated, kickers 50 will disgorge a tubular from resting on either or both of arm 18 or trolley 30 so as to roll the tubular off the catwalk, over lateral transfers 36 and onto pipe racks 28.
Catwalk 10 includes longitudinally extending bracing 38 mounted on opposite sides of channel 10a and extending the longitudinal length over main skid 40. A hydraulic power unit 42 may be mounted in the outboard end, the end distal from mast 12. Pivot supports 44 are mounted at the opposite inboard end of catwalk 10 for pivotally supporting mast 12 thereon.
Tubular transport arm 18 and tubular transport trolley 30 run along lower tracks 46 within channel 10a on rollers 18c and 30b respectively. Rollers 18d on the inboard end of arm 18 run in tracks 34 as the inboard end 18b of arm 18 is hoisted upwardly along the base section of 12a of pipe handler mast 12. As arm 18a is hoisted upwardly along mast 12, arm 18 pivots on hinges 48 relative to trolley 30 which remains horizontal within channel 10a in catwalk 10 unless the hinge has been pinned or otherwise disabled so that arm 18 and trolley 30 move together. As described elsewhere herein, hinges 48 are disabled when it is desired to deliver an object which is longer than a tubular, such as a length of casing, for example for making up a double length casing for delivery to well center. Thus trolley 30 translates in direction D towards mast 12 as arm 18 is hoisted so as to deliver a tubular 20 into the base section of 12a of mast 12. Base section 12a is advantageously primarily only supported along its sides and is substantially open front and back for delivery of tubulars into and out of base section 12a.
A skate drive motor 52 is mounted at the outboard end, that is, the end opposite to hinges 48, in trolley 30. Skate drive motor 52 drives a gear box 54 containing a planetary drive, gear box 54 driving a skate drive shaft 58 via drive chain 56. The endless skate drive chains 62, which carry skates 32 thereon, are driven by sprockets 60 mounted on drive shaft 58. Endless skate drive chains 62 are driven by sprocket 60 at the outboard end of trolley 30, and pass around inboard idler sprockets 64 at the inboard end of arm 18, skate drive chain 62 passing through hinges 48 so as to be operative while arm 18 is either horizontal or in an inclined position for example nested flush within base section 12a of mast 12.
The balance of the pipe handler mast will now be explained. Upper section 12b of pipe handler mast 12 is mounted onto the upper end of base section 12a. In the embodiment of
The inboard truss work of upper section 12b may be offset laterally relative to supports 12b′ so as to not interfere with pipe stand 8 being extended in direction A from tubular transport arm 18 and through wrench 22 by pipe stand elevators 24.
In a preferred embodiment, a platform 68 is rigidly mounted to the uppermost end of upper section 12b of mast 12, for example by means of bracing 68a. An articulated robotic arm 70 may be mounted on top of platform 68 so as to be adjacent pipe stand 8 extending along trajectory B from mast 12. Robotic arm 70 includes a pipe stand gripper 72 mounted at the distal end of one or more articulated arm segments 74 atop, for example, a rotating base section 76. Robotic arm 70 is adapted to be selectively rotated about a vertical axis of rotation E, hereinafter referred to as slewing. Slewing as used herein means rotation of robotic arm 70 in direction F about axis of rotation E. Advantageously, gripper 72 contains a plurality of pipe gripping mechanisms, which may be linearly spaced apart along the length of the pipe to be gripped, and wherein gripper 72 is pivotally mounted to the distal end of the adjacent articulated arm segment 74 for rotation of gripper 72 about lateral axis rotation G in direction H.
An anti-sway structure such as U-shaped frame member 78 is provided for stabilizing, laterally, mast 12 to the drilling rig mast 14 without substantially vertically reacting loading on mast 12 to mast 14. Mast 12 may for example be stabilized to the front legs 14a of the drilling rig mast 14, although other ways of stabilizing mast 12 to mast 14 or rig substructure 16 would also work. U-shaped frame member 78 may be for example pinned at ends 78a to legs 14a so that the base end 78b may be pinned to the uppermost end of upper section 12b of mast 12 to provide further support to the upper end of pipe handler mast 12. Frame member 78 may be quickly attached and to, detached from, front legs 14a of mast 14 so as to not interfere with the portability of the catwalk and pipe handler mast system.
The use of robotic arm 70 provides for the primary purpose of tripping pipe stands into and out of the well. Thus robotic arm 70 effectively transfers pipe or pipe stands or lengths of casing between the top drive elevators at or near well center and the racking board for tripping. Robotic arm 70 also provides a secondary purpose; namely, delivering the upper end of pipe stand 8 from the stand-building axis of trajectory B to the hand-off window for top drive elevators 26a. In particular, once pipe stand 8 has been extended by the pipe stand elevators 24 from the upper end of mast 12, grippers 72 are engaged with the adjacent tubular walls of the pipe stand and the pipe stand then elevated as necessary to clear the bottom end of the pipe stand from interfering with the upper floor of substructure 16, and once so elevated, pipe stand 8 may be rotated to the vertical and translated along one side or the other of platform 68 to thereafter either rack the pipe stand 8 into the racking board 14b mounted to legs 14a (so as to rack the pipe stand for storage between the racking board fingers), or so as to present the pipe stand to well centre 80, for example, so as to be substantially parallel to and collinear with or adjacent to well centre axis I whereupon the upper end of the pipe stand may be engaged by the top drive elevators 26a. This then provides a second mechanism for handing off to the top drive within mast 14 a pipe stand 8 which has been made up within mast 12.
In the alternative embodiment depicted commencing in
As before, the inboard end 18b of tubular transport arm 18 is elevated up along base section 12a as rollers 18d travel in tracks 34 running the length of base section 12a inset laterally from the outer trusses. A winch 82 which may be mounted for example at the lower end of base section 12a, or other actuators as would be known to one skilled in the art, are used to selectively elevate inboard end 18b to thereby draw arm 18 up from its horizontal position when laid within catwalk 10 to its fully inclined position within base section 12a to thereby carry a tubular 20 from the catwalk to its pipe stand building position under wrench 22. As with upper section 12b, elevators 24 are selectively translated along the length of beam 12c and may employ collars 24a mounted on the ends of arms 24b, where the arms 24b are rotatable relative to either beam 12c or upper section 12b by the use of for example actuators 24c to thereby position collars 24a under the pipe stand tool joints. Collars 24a fit snugly under the tool joint and around the adjacent tubular so that the pipe stand may be elevated in direction A relative to mast 12. A tubular support 84 may be mounted at the upper most end of beam 12c to hold a pipe stand 8 in position once elevated by elevator 24 while elevator 24 is retracted from contact with pipe stand and lowered to engage a tool joint lower on the pipe stand. Tubular support 84 may, similar to elevator 24 employ an open collar which engages under tool joint snugly around the tubular.
What follows now, with reference to
Once skate 32 has translated tubular 20′ upwardly through wrench 22 the upper tool joint of tubular 20′ is engaged by pipe stand elevator 24 allowing skate 32 to retract downwardly along arm 18 as arm 18 is lowered by winches 82 once again into its horizontal position as seen in
The cycle then repeats as arm 18 is lowered to the horizontal and the third pipe stand 20′″ is then loaded onto the catwalk from the pipe stands, advanced by skate 32 to the inboard end of arm 18, and arm 18 elevated from the horizontal to the fully inclined position within base section 12a whereupon skate 32 continues to advance the third tubular 20′″ until its upper end engages into wrench 22 and the spinner and wrench of wrench 22 make up the third tubular 20′″ into the pipe stand so as to complete a triple pipe stand as seen in
It understood that although the sequence has been described in making up the pipe stands, with the sequence reversed, pipe stands may be broken down so as to return single tubulars to the pipe racks or otherwise for storage once taken off the catwalk.
In one embodiment, a top drive retraction system may be provided so that once a pipe stand has been handed off from the top drive elevators to the pipe handling system according to the present invention, during the tripping-out operation the top drive may be returning empty to the rig floor as the pipe stand that has been removed is being either racked or broken down for storage and conversely while tripping-in while the top drive is engaged with the drill string, the pipe handling system according to the present invention may be readying the next pipe stand and positioning it while the top drive is returning empty from the rig floor. The steps for this procedure are set out in tabular form in
The various options the drill rig operator will have while employing the portable pipe handling system according to the present invention are set out diagrammatically in
In the above embodiments single tubulars 20 are advanced up the mast 12 using the skate 32 on the tubular transfer arm 18 and then the single tubular 20 is held in the mast by a tubular support 84 or other support arm, etc, while the tubular transfer arm 18 returns to the catwalk 10 to retrieve the next single tubular. The second tubular is then returned to the mast on the tubular transfer arm and advanced up to the wrench 22 for mating with the first tubular. Depending on the length of the single tubulars it may be necessary to upwardly advance the upper single tubular (or double pipe stand if two tubulars have already been made up) along the stand builder mast axis B further than the skate 32 on the arm 18 can push the tubular(s). Consequently, it may be advantageous to mount one or more clamping “v” rollers 86, as an alternative to the use of the elevators 24, in the stand building mast 12, above the wrench in upper section 12b, so that the clamping “v” rollers, which include selectively driven rollers 86a, may further advance the upper tubular upwardly along the mast upwardly from the wrench. The clamping “v” rollers 86 may be, as illustrated, an opposed pair of driven rollers 86a. A pair of clamping “v” rollers 86 may be mounted spaced apart along the upper mast section 12b above the wrench. In particular as illustrated two sets of clamping “v” rollers are mounted spaced several feet apart along the stand building axis of trajectory B. This provides selective control over all degrees of freedom of the upper tubular held in the mast. The clamping “v” rollers 86 include clamping cylinders 86b so as to engage the rollers 86a against the tubular 20 with sufficient force to both hold and lift the weight of the pipe stand 8 by tractive frictional contact alone. “V” rollers 86 include motors 86c which may be electric, hydraulic, pneumatic, etc as would be known to one skilled in the art. Cylinders 86b move collars 86d along cross-bracing member 13 in mast 12 so as to selectively vary distance “d” between the rollers.
As seen in
This application is a continuation of U.S. patent application Ser. No. 13/573,878 filed 11 Oct. 2012, which claims priority to U.S. Provisional Patent Application Ser. No. 61/545,989 filed Oct. 11, 2011, which is hereby incorporated by reference herein in its entirety. Priority is claimed to this earlier-filed application under 35 U.S.C. § 120.
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20160002988 A1 | Jan 2016 | US |
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Number | Date | Country | |
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Parent | 13573878 | Oct 2012 | US |
Child | 14792311 | US |