TECHNICAL FIELD

[0001] This invention relates broadly to the field of drilling, and more particularly to a drilling arrangement and an associated method of drilling.

BACKGROUND ART

[0002] The following discussion of the background art is intended to facilitate an understanding of the present invention only. The discussion is not an acknowledgement or admission that any of the material referred to is or was part of the common general knowledge as at the priority date of the application .

[0003] As generally known in the art, a drilling rig is an integrated system that drills wells, such as oil or water wells. Drilling rigs can also be used to sample sub-surface mineral deposits, test rock, soil and groundwater physical properties, and can also be used to install sub-surface fabrications, such as underground utilities, instrumentation, tunnels or wells. Drilling rigs can be mobile equipment mounted on trucks, tracks or trailers, or more permanent land or marine-based structures. The term "rig" generally refers to the equipment that is collectively used to penetrate the surface of the Earth's crust.

[0004] Terrestrial or land-based drill rigs capable of drilling to significant depths, such as 10 000 metres or more, typically comprise large pieces of equipment. Major components of such a rig may include mud tanks, mud pumps, a derrick or mast, drawworks or hoisting equipment, a rotary table or top drive, and a drillstring. Larger rigs are capable of drilling through thousands of metres of the Earth's crust, using mud pumps to circulate drilling mud (slurry) through the drill bit and up a casing annulus, for cooling and removing the cuttings while a well is drilled. Drawworks or hoisting equipment and the derrick or mast with top drive are required to lift and handle hundreds of tons of drill pipe forming part of the drillstring. Out of necessity, such components are generally large in order to handle the weight of the drillstring and to impart the necessary torque in order to drill to significant depth .

[0005] In light hereof, Applicant has identified a need in the art for a drilling arrangement capable of drilling to significant depths, which is also road-transportable and relatively mobile . Additionally, autonomous or semi-autonomous operation of such a drilling arrangement is also desirous.

[0006] The current invention was conceived with this goal in mind.

SUMMARY OF THE INVENTION

[0007] The skilled addressee is to appreciate that reference herein to a 'truck' includes broad reference to any suitable motor vehicle designed to transport cargo or carry specialised payloads, including any of various forms of vehicle for carrying goods and materials, usually consisting of a single self-propelled unit but also often composed of a trailer vehicle hauled by a tractor unit, or associated wheeled frame used for transporting heavy objects. [ 0008 ] According to a first aspect of the invention there is provided a drilling arrangement comprising : a truck-mounted rotary table stage for placement over a blowout preventer (BOP ) operatively installed in a pilot hole where a well is to be drilled; a truck-mounted drilling mast comprising a rotary head drive displaceable along said mast to ef fect dri lling, said drilling mast engageable with the rotary table stage ; a truck-mounted drill pipe gripper configured to engage with the rotary table stage and selectively to grip and hold a drill string; a truck-mounted drill pipe loading assembly conf igured automatically to load sections of drill pipe to said drilling mast to form a drill string; and at least one section of torque trans ference pipe which comprises rotary head couplings defined proximate either end thereof , the torque trans ference pipe engageable with the drill string; wherein the drill ing arrangement i s configured to drill a well by : i . the pipe loading assembly interchanging drill pipe sections with the at least one section of torque trans ference pipe within the drill string; ii . the rotary head drive applying dri lling torque only when engaged with the rotary head couplings of the torque trans ference pipe ; and iii . the gripper gripping the drill string to facilitate the interchanging of drill pipe and torque trans ference pipe and the rotary head drive moving between rotary head couplings . [0009] The skilled addressee is to appreciate that the drilling arrangement extends the drill string into the well by interchanging drill pipe sections with the at least one torque transference pipe section so that the rotary head drive applies torque to the drill string only when engaged with the rotary head couplings of the torque transference pipe section. The gripper grips the drill string to allow the pipe loading assembly to interchange between drill pipe sections and the torque transference pipe sections to extend the drill string. In this manner, a single section of torque transference pipe can be used to drill and extend the drill string. The gripper also grips the drill string to allow the rotary head drive to move from a lower rotary head coupling of the torque transference pipe section to an upper rotary head coupling as the well is drilled.

[0010] Additionally, it is to be appreciated that operation of the drilling arrangement is generally reversible in order to remove drill string sections, i.e. drill pipe sections and torque transference pipe sections, from a well. Accordingly, description of such drilling operation herein includes an inverse order, as appropriate.

[0011] In an embodiment, a truck on which a component, i.e. rotary table stage, drilling mast, drill pipe gripper and/or drill pipe loading assembly, is mounted comprises an automated and/or autonomous platform.

[0012] In an embodiment, a truck-mounted component is mounted in a deployable manner where a component is deployable from a stowed position with a reduced footprint for transport purposes, and a deployed position to perform a task as described . [ 0013 ] In an embodiment , the drilling mast is pivotably arranged on the truck so that the mast is deployable between a transport position, in which the mast lies along the truck, and a drilling position, in which the mast is in a substantially upright position to ef fect drilling .

[ 0014 ] Typically, a truck-mounted component includes stabilisers configured to stabilise said component on a surface in which the well is to be drilled .

[ 0015 ] In an embodiment , the drill pipe loading assembly comprises a handling arm for handling a drill pipe section or a torque trans ference pipe section, and a handler mechanism configured automatically to displace , orientate and/or rotate said pipe section for engagement with the drill string .

[ 0016 ] In an embodiment , the drilling arrangement comprises a truck-mounted mud system which is configured to supply drilling mud to the drill string .

[ 0017 ] According to a second aspect of the invention there is provided a drilling methodology comprising the steps of : positioning a truck-mounted rotary table stage over a blowout preventer (BOP ) installed in a pilot hole where a well is to be drilled; engaging a truck-mounted drilling mast comprising a rotary head drive displaceable along said mast to ef fect drilling with the rotary table stage ; engaging a truck-mounted drill pipe gripper configured selectively to grip and hold a drill string with the rotary table stage ; positioning a truck-mounted drill pipe loading assembly configured automatically to load sections of drill pipe to the drilling mast to form a drill string; and drilling a well by i . interchanging, via the pipe loading assembly, within the drill string between drill pipe sections and at least one section of torque trans ference pipe which comprises rotary head couplings defined proximate either end thereof ; ii . applying drilling torque , via the rotary head drive , to the rotary head couplings of the torque trans ference pipe ; and iii . gripping as necessary, via the gripper, the drill string to facilitate the interchanging of drill pipe and torque trans ference pipe sections and when the rotary head drive moves between rotary head couplings along the torque trans ference pipe section .

[ 0018 ] In an embodiment , the methodology includes supplying drilling mud to the drill string via a truck-mounted mud system .

[ 0019 ] According to a further aspect of the invention there is provided a drilling arrangement and a drilling methodology, substantially as herein described and/or illustrated .

BRIEF DESCRIPTION OF THE DRAWINGS

The description will be made with reference to the accompanying drawings in which : Figure 1 is a diagrammatic representation of a surface in which a well is to be drilled, said surface including a blowout preventer (BOP ) installed in a pilot hole ;

Figure 2 is a diagrammatic representation of a truckmounted rotary table stage of a drilling arrangement for placement over the blowout preventer (BOP ) of Figure 1 ;

Figure 3 is diagrammatic representation of a truckmounted drilling mast of the drilling arrangement engaged with the rotary table stage of Figure 2 ;

Figure 4 is a diagrammatic representation of a truckmounted drill pipe gripper of the drilling arrangement engaged with the rotary table stage of Figure 2 ;

Figure 5 is a diagrammatic representation of a truckmounted drill pipe loading assembly for loading drill pipe sections to the drilling mast of Figure 3 , including a mud system;

Figure 6 is a diagrammatic representation of the pipe loading assembly of Figure 5 , including a handling arm and drill pipe section supply;

Figure 7 is a diagrammatic representation of the pipe loading assembly loading a section of torque trans ference pipe into a drill string;

Figure 8 is a diagrammatic representation of a rotary head drive of the drilling arrangement drilling a well by applying torque to the torque trans ference pipe section; Figure 9 is diagrammatic representation of the rotary head drive moving between rotary head couplings of the torque trans ference pipe section; and

Figure 10 is a diagrammatic representation of the gripper gripping the drill string to facilitate the rotary head drive to moving between rotary head couplings of the torque trans ference pipe section .

DETAILED DESCRIPTION OF EMBODIMENTS

[ 0020 ] Further features of the present invention are more fully described in the following description of several nonlimiting embodiments thereof . This description is included solely for the purposes of exempli fying the present invention to the skilled addressee . It should not be understood as a restriction on the broad summary, disclosure or description of the invention as set out above .

[ 0021 ] In the figures , incorporated to illustrate features of the example embodiment or embodiments , like reference numerals are used to identi fy like parts throughout . Additionally, features , mechanisms and aspects well-known and understood in the art will not be described in detail , as such features , mechanisms and aspects will be within the understanding of the skilled addressee .

[ 0022 ] The present invention broadly provides for a drilling arrangement 10 which is capable of drilling to signi ficant depths , e . g . 10 000 metres or more , but which is also road-transportable and mobile . The drilling arrangement 10 exempli fied herein is also capable of autonomous or semi- autonomous operation, as will become apparent to the skilled addressee . Drilling arrangement 10 finds particular application in oil and gas operations , as well as geothermal drilling applications . Of course , other uses are included and within the scope of the present invention .

[ 0023 ] With reference now to the accompanying figures , there is shown one possible embodiment of the drilling arrangement 10 which is useable to drill a well into a surface 6 . In order to provide for a drill ing arrangement 10 which is capable of drilling to depth, but is also road-transportable and relatively mobile in comparison to conventional drilling rigs , drilling arrangement 10 is comprised of a number of components that are truck-mounted, as shown in the figures and described in more detail below . In one embodiment , such truckmounted parts or components are deployable over or proximate a pilot hole 8 where a well is to be drilled, typically including a blowout preventer (BOP ) 14 or associated wellhead components .

[ 0024 ] In the exempli fied embodiment , such truck-mounted components , as described in more detail below, are typically mounted in a deployable manner, where a component is deployable from a stowed pos ition with a reduced footprint for transport purposes , and a deployed position to perform a task as described . A manner of deployment may vary, with typical examples including hydraulic or pneumatic actuators , electromagnetic actuators , and/or the like . Additionally, such truck-mounted components are mounted on truck platforms that typically include stabilisers 34 configured to stabilise said components on the surface 6 in which the well is to be drilled, e . g . hydraulic stabiliser legs , electromagnetic actuated stabilisers , etc . Such deployment and stabilising mechanism and actuators are known in the art and will not be described in detail herein .

[ 0025 ] As shown in Figure 2 , drilling arrangement 10 includes a truck-mounted rotary table stage 12 which is configured for placement over the BOP 14 or associated wellhead components . The rotary table stage 12 may include a stabilising framework for positioning the rotary table stage as required over the BOP 14 , in order to form a stable base for drilling operations .

[ 0026 ] Drilling arrangement 10 also includes a truckmounted drilling mast 16 which comprises a rotary head drive 18 which is displaceable along the mast 16 to ef fect drilling . As shown in Figure 3 , the drilling mast 16 is configured to be engageable with the rotary table stage 12 . Such engagement may take a variety of forms , typically mechanical , electromechanical , hydraulic, or the like , and will be within the understanding of the skilled addressee . The dri lling mast 16 is typically pivotably arranged on the truck which carries it so that the mast 16 is deployable between a transport position, in which the mast 16 lies along the truck, and a drilling position, in which the mast 16 is in a substantially upright position to ef fect drilling . Notably, the drilling mast 16 is typically compact as compared to conventional deepdrilling drill rigs capable of drilling to significant depths .

[ 0027 ] As shown in Figure 4 , drilling arrangement 10 also include a truck-mounted drill pipe gripper 20 which is configured to engage with the rotary table stage 12 and selectively to grip and hold a drill string 22 , as described in more detail below . Drilling arrangement 10 further includes a truck-mounted drill pipe loading assembly 24 , examples of which are shown in figures 5 and 6 , which is configured automatically to load sections of drill pipe to the drilling mast 16 to form a drill string .

[ 0028 ] In the exempli fied embodiment , the drill pipe loading assembly 24 comprises a handling arm 36 for handling a drill pipe section 26 or a torque trans ference pipe section 28 , as well as a handler mechanism 38 which is configured automatically to displace , orientate and/or rotate said pipe sections 26 and 28 for engagement with the drill string 22 . In such an embodiment , the drilling arrangement 10 also comprises a truck-mounted mud system 40 which is configured to supply drilling mud to the drill string 22 . In this case , the mud system 40 is coupled to the handler mechanism 38 which forms the end of the drill string 22 , as shown .

[ 0029 ] As shown in the exempli fied embodiment , the truckmounted components are typically positioned radially about the well , but of course variations hereon are possible and expected . Additionally, one or more truck-mounted components may be located on one or more trucks . For example , the drill pipe loading assembly 24 and the mud system 40 of the exempli fied embodiment are shared between to truck platforms , with a drill pipe section supply 42 and handling arm 36 on one truck, and the mud system 40 and handler mechanism 38 on another truck . Again, this is but one example and variations hereon are possible and expected .

[ 0030 ] Importantly, the drilling arrangement 10 includes at least one section of torque trans ference pipe 28 which comprises rotary head couplings 30 that are typically defined proximate either end 32 thereof , an example of which is shown in Figure 7 . The torque trans ference pipe 28 is engageable with the drill string 22 which typically comprises drill pipe sections, e.g. threadable into the drill string.

[0031] In this manner, the drilling arrangement 10 is configured to drill a well by the pipe loading assembly 24 interchanging drill pipe sections 26 with the at least one section of torque transference pipe 28 within the drill string 22, with the rotary head drive 18 applying drilling torque only when engaged with the rotary head couplings 30 of the torque transference pipe 28, i.e. no torque is directly applied to drill pipe sections 26 of the drill string 22. Importantly, the pipe gripper 20 selectively grips the drill string 22 to facilitate the interchanging of drill pipe 26 and torque transference pipe 28 sections onto the drill string 22, as well as when the rotary head drive 18 needs to move between rotary head couplings 30 on the torque transference pipe section 28.

[0032] Such drilling operation is shown in Figures 8 to 10, where a relatively short and compact drilling mast 16 with rotary head drive 18 can be used to drill to significant depths by the rotary drive head 18 only applying drilling torque to the drill string 22 via the torque transference pipe section (s) 28, specifically the rotary head couplings 30. Such torque transference pipe section (s) 28 are selectively interchanged with conventional drilling pipe sections 26 to extend the drill string 22 into the well, but using the pipe gripper 20, the torque transference pipe section (s) 28 are used to drill the well, but then removed (while the drill string 22 is held in place by the gripper 20) and replaced with conventional drill pipe sections 26. [0033] In such a manner, one or more of the torque transference pipe section (s) 28 can be used for torque transfer from the rotary head drive 18 to drill the well, so that the rotary head drive 18 does not apply direct torque to the drill pipe sections 26. The torque transference pipe section (s) 28 are generally manufactured smaller than conventional 12 metre drill pipe sections and more robust, i.e. stronger. This allows multiple torque transference pipe section (s) 28 to be used to drill, after which they are removed from the well and conventional drill pipe sections are fitted so that the entire borehole assembly is lowered into the well without direct torque transfer applied to the conventional drill pipe sections 26.

[0034] Such an arrangement allows the constituent components of drilling rig 10 to be more compact in size as compared to conventional drilling rigs. In particular, use of shorter sections of torque transference pipe 28, via which drilling torque is applied to the overall drilling string 22, enables the use of a shorter drilling mast 16, whilst drilling arrangement 10 is still capable of drilling to significant depths .

[0035] The skilled addressee is to appreciate that the rotary head couplings 30 on the ends 32 of the torque transference pipe section (s) 28 may take a variety of forms, but are generally configured to allow the rotary head drive 18 to apply significant torque thereto. For example, a slotted keyway or similar mechanical configuration may be used, or the like .

[0036] Figure 10 shows an example of the pipe gripper 20 which is configured selectively to grip and hold the drill string 22 to facilitate the interchanging of drill pipe 26 and torque transference pipe 28 sections onto the drill string 22, as well as when the rotary head drive 18 needs to move between rotary head couplings 30 on the torque transference pipe section 28. For example, when drilling and after a torque transference pipe section 28 has been fitted to the drill string 22, the rotary drive head 18 engages with a lower rotary head coupling 30 and applies torque thereto to drill. As the drill string 22 into the well, the gripper 20 grips the drill string 22 once the rotary drive 18 is proximate the rotary table stage 12.

[0037] As the drill string 22 is gripped and held in place, the rotary head drive 18 can decouple from the lower rotary head coupling 30 and move back up on the mast until it is able to couple with the upper rotary head coupling 30 to continue drilling. Once such a drilling cycle is completed, the drill string 22 can be pulled from the well to allow removal of the torque transference pipe section (s) 28 and replacement with conventional drill pipe sections 26, with the drill string 22 lowered into the well again, after which another such drilling cycle can be repeated until a desired drilling depth is reached .

[0038] Importantly, in an embodiment, drilling arrangement 10 can be automated or made autonomous. For example, a truck on which a component, i.e. rotary table stage 12, drilling mast 16, drill pipe gripper 20 and/or drill pipe loading assembly 24, is mounted, may comprise an automated and/or autonomous platform, e.g. self-driving vehicle. Similarly, all of the respective components of drilling arrangement 10, i.e. rotary table stage 12, drilling mast 16, drill pipe gripper 20 and/or drill pipe loading assembly 24, can be automated or made autonomous , where such components act in a complementary manner in order to perform drilling cycles , as required .

[ 0039 ] Accordingly, drilling arrangement 10 may include a suitable controller and associated control network (not shown) via which operation of the individual components can be arranged in signal communications and synchronised for such automated and/or autonomous operation . Such automation is known in the art and speci fic details thereof will be within the understanding of the skilled addressee .

[ 0040 ] In light of the above , the present invention also includes an associated drilling methodology which broadly comprises the steps of positioning the truck-mounted rotary table stage 12 over the blowout preventer (BOP ) 14 installed in a pilot hole 8 where a well is to be drilled, and engaging the truck-mounted drilling mast 16 comprising the rotary head drive 18 , which is displaceable along the mast 16 to ef fect drilling, with the rotary table stage 12 . The method then includes the step of engaging the truck-mounted drill pipe gripper 20 , which is configured selectively to grip and hold the drill string 22 , with the rotary table stage 12 .

[ 0041 ] Then, the method comprises the step of positioning the truck-mounted drill pipe loading assembly 24 , which is configured automatically to load sections of drill pipe 26 to the drilling mast 16 to form the drill string 22 , and drilling a well by the components performing a drilling cycle , as described above .

[ 0042 ] Speci fically, such a step of drilling or a drilling cycle generally includes interchanging, via the pipe loading assembly 24 , within the drill string 22 between drill pipe sections 26 and at least one section of torque trans ference pipe 28 , which comprises rotary head couplings 30 defined proximate either end 32 thereof , applying drilling torque , via the rotary head drive 18 , to the rotary head couplings 30 of the torque trans ference pipe section 28 , and gripping as necessary, via the gripper 20 , the drill string 22 to facilitate the interchanging of drill pipe and torque trans ference pipe sections 26 and 28 and, when the rotary head drive 18 needs to move between upper and lower rotary head couplings 30 of the torque trans ference pipe section 28 .

[ 0043 ] In one embodiment , the methodology also includes the step of supplying drilling mud to the drill string via the truck-mounted mud system 40 .

[ 0044 ] Applicant believes it particularly advantageous that the present invention provides for drilling arrangement 10 , as well as associated drilling methodology, using speci fic components and drilling techniques using specially configured torque trans ference pipe section ( s ) 28 to allow drilling to signi ficant depths , whilst being road-transportable and relatively mobile in comparison to convention deep-drilling rigs . In particular, conventional tall mast structures are made redundant via the use of the torque trans ference pipe section ( s ) 28 . Additionally, operation of drilling arrangement 10 can be automated and/or autonomous .

[ 0045 ] Optional embodiments of the present invention may also be said to broadly consist in the parts , elements and features referred to or indicated herein, individually or collectively, in any or all combinations of two or more of the parts , elements or features , and wherein speci fic integers are mentioned herein which have known equivalents in the art to which the invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth. In the example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail, as such will be readily understood by the skilled addressee .

[0046] The use of the terms "a", "an", "said", "the", and/or similar referents in the context of describing various embodiments (especially in the context of the claimed subject matter) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms "comprising," "having," "including, " and "containing" are to be construed as open- ended terms (i.e., meaning "including, but not limited to,") unless otherwise noted. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. No language in the specification should be construed as indicating any non-claimed subject matter as essential to the practice of the claimed subject matter .

[0047] Spatially relative terms, such as "inner," "outer," "beneath, " "below, " "lower, " "above, " "upper, " and the like, may be used herein for ease of description to describe one element or feature's relationship to another element (s) or feature (s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the example term "below" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0048] It is to be appreciated that reference to "one example" or "an example" of the invention, or similar exemplary language (e.g., "such as") herein, is not made in an exclusive sense. Various substantially and specifically practical and useful exemplary embodiments of the claimed subject matter are described herein, textually and/or graphically, for carrying out the claimed subject matter.

[0049] Accordingly, one example may exemplify certain aspects of the invention, whilst other aspects are exemplified in a different example. These examples are intended to assist the skilled person in performing the invention and are not intended to limit the overall scope of the invention in any way unless the context clearly indicates otherwise. Variations (e.g. modifications and/or enhancements) of one or more embodiments described herein might become apparent to those of ordinary skill in the art upon reading this application. The inventor (s) expects skilled artisans to employ such variations as appropriate, and the inventor (s) intends for the claimed subject matter to be practiced other than as specifically described herein.

[0050] Any method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.