Directional drill dogleg adjustment system and method for adjustment of the same

Abstract

Directional drill dogleg adjustment system (300) suitable for use in a directional drill (10) and method for adjustment of the same enabling adjustment of a dogleg setting of the directional drill (10) in-situ. Fig. 2a.

Description

[0001] Directional drill dogleg adjustment system and method for adjustment of the same

[0002] The disclosed embodiments relate to a directional drill dogleg adjustment system and method for adjustment of the same.

[0003] The disclosed embodiments further relate to a directional drill dogleg adjustment system and method for adjustment of the same, enabling adjustment of the deflection angle of a directional drill.

[0004] Background

[0005] Directional drilling systems, particularly as used in the mineral exploration industry, often consist of a rotating inner element and a non-rotating outer element. The rotating inner element connects to the drill string in one end and the drill bit in the other end. During the drilling operation, the inner element transfers the rotation from the drill string to the drill bit. The non-rotating outer element sits outside the rotating inner element and contains at minimum a deflection device and an antirotation device. The deflection device exerts a force on the rotating inner element that causes it to bend or deflect, resulting in the drill bit being angled in relation to the remainder of the directional drill. The anti-rotation device may consist of a gripping system that engages the borehole wall to prevent the outer element from rotating during the drilling operation. Preventing the rotation secures that the deflection device, and thereby the angle of the drill bit, is in a fixed orientation during the drilling operation, which causes the directional drill to deflect the borehole.

[0006] The intensity of the directional drilling, i.e. the radius of the borehole, is controlled by the angle of the drill bit as created by the deflection device. However, it is also affected by the rock formation, drilling parameters and conditions of the drilling equipment, hence the deflection device is often made configurable in some way. An example of this is found in CA2749316C / AU2011213876 -Adjustable eccentric bushing assembly. The configuration adjustment may for instance entail replacing or adjusting parts in the deflection device. The specific configuration of the deflection device at any given time is referred to as the dogleg setting of the directional drill.

[0007] The dogleg setting must be manually adjusted by hand on the drill itself, meaning the directional drill must first be retrieved from the drill hole, which can be up to and longer than 1 km. This extraction of the drill string every time the drill requires a dogleg adjustment is hugely time consuming and costly process. Repeated extraction is further a safety concern due to the physical labour involved, while it also increases the wear and tear on the directional drill itself. These drawbacks of the current operation will often lead to the directional drilling being performed at anon-optimal intensity, e.g. slightly different radius than what the drilling plan calls for. This may on one side lead to prolonged directional drilling and further time loss or other the other side lead to higher wear on drilling equipment and challenging drill hole conditions.

[0008] Ideally adjustments of the dogleg setting would be done with the directional drill remaining in the hole without the need to extract the drill string.

[0009] There is thus a need for a directional drill dogleg adjustment system and method for adjustment of the same solving the issues of the prior art solutions.

[0010] Summary

[0011] Provided herein is a directional drill dogleg adjustment system and method for adjustment of the same.

[0012] Also provided herein is a directional drill dogleg adjustment system and method for adjustment of the same removing the need for retrieving the directional drill from a drill hole to adjust the dogleg setting.

[0013] Provided herein is a directional drill dogleg adjustment system and method for adjustment of the same enabling the use of a dogleg setting control assembly for adjustment of the dogleg setting in-situ.

[0014] Also provided herein is a directional drill dogleg adjustment system and method for adjustment of the same providing a mechanical solution that does not require any external locking system to hold the dogleg setting.

[0015] Provided herein is a directional drill dogleg adjustment system and method for adjustment of the same utilizing long and low angled slots that self-locks the dogleg setting of the directional drill during drilling.

[0016] Also provided herein is a directional drill dogleg adjustment system resulting in at least an axially shorter directional drill, compared to prior art directional drill, but also a directional drill being thinner than prior art directional drills.The invention

[0017] A directional drill dogleg adjustment system according to the present invention is defined by the technical features of claim 1. Preferable features of the directional drill dogleg adjustment system are described in the dependent system claims.

[0018] A method for adjusting a dogleg setting of a directional drill dogleg adjustment system according to the present invention is defined by the technical features of claim 8. Preferable features of the method are described in the dependent method claims.

[0019] The inventive embodiments of the present invention are related to a directional drill dogleg adjustment system (DDDLAS) allowing the dogleg setting of the directional drill to be adjusted while the directional drill is in-situ.

[0020] The present invention is suitable for directional drills having an outer element and an inner element.

[0021] The DDDLAS according to the present invention comprises a dogleg setting control assembly housed in the directional drill, and an inner assembly. In accordance with the DDDLAS according to the present invention, the inner assembly comprising an actuator releasably coupled at an axial distal end thereof. The inner assembly according to the present invention is configured for, from the surface, deployment into and retrieval from the directional drill while the directional drill is in-situ, i.e. downhole.

[0022] The inner assembly according to the present invention is configured, when deployed into the directional drill, to engage and actuate the dogleg setting control assembly to adjust a dogleg setting of the directional drill in-situ.

[0023] In accordance with one embodiment of the present invention, the dogleg setting control assembly comprises a deflection assembly configured to vary an angle between at least two adjacent portions or sections of the directional drill.

[0024] According to one embodiment of the DDDLAS according to the present invention, the dogleg setting control assembly further contains a manipulator assembly configured to receive the inner assembly in-situ, i.e. downhole, and varying the dogleg setting of the directional drill according to the actuator.

[0025] In accordance with an embodiment of the DDDLAS according to the present invention, the deflection assembly comprises a pair of elongated members, each of the pair of elongated membersbeing pivotably coupled at a first axial distal end in the directional drill. The mentioned pair of elongated members are further each operably connected at a second axial distal end with a sliding block and a slot arrangement, wherein the sliding block is constrained within an angled slot extending axially towards a proximal end of the directional drill such that the deflection assembly is configured by adjusting the position of the sliding block within the angled slots.

[0026] According to an embodiment of the DDDLAS according to the present invention, the inner assembly is configured for releasably coupling one of a plurality of actuators, each of the plurality of actuators corresponding to a different and discrete dogleg setting.

[0027] In accordance with one embodiment of the DDDLAS according to the present invention, the inner assembly is configured for releasably coupling to an adjustable actuator enabling the use of the same adjustable actuator for different and discrete dogleg settings.

[0028] In accordance with a further embodiment of the DDDLAS according to the present invention, each of the plurality of actuators is provided with a linear length differing from each of the other of the plurality of actuators configured for engaging with the inner assembly for operating the dogleg setting control assembly to adjust the dogleg setting for a distinct dogleg setting.

[0029] According to a further embodiment of the DDDLAS according to the present invention, the adjustable actuator is adjustable in axial length for engaging with the inner assembly for operating the dogleg setting control assembly to adjust the dogleg setting for a distinct dogleg setting.

[0030] According to a further embodiment of the DDDLAS according to the present invention, the actuator comprises a substantially linear portion such that the distinct dogleg setting corresponds to the substantially linear portion of a respective one of the plurality of actuators.

[0031] A method of adjustinga dogleg setting of a directional drill dogleg adjustment system in a directional drill comprises a step of providing a dogleg setting control assembly within a directional drill, wherein the directional drill has an inner assembly being configured for, from the surface, deployment into and retrieval from the directional drill while the directional drill is in-situ.

[0032] The method according to the present invention further comprises a step of retrieving the inner assembly from the directional drill to the surface.

[0033] Moreover, the method according to the present invention comprises coupling one of a plurality of actuators with the inner assembly of the dogleg setting control assembly, wherein the coupled actuator comprises a linear portion associated with a desired dogleg setting.The method according to the present invention further comprises deploying the inner assembly with the coupled actuator in the directional drill in-situ to engage a manipulator assembly which in turn operates a deflection assembly of the dogleg setting control assembly to set a desired dogleg setting of the directional drill.

[0034] In accordance with one embodiment of the method according to the present invention, it comprises varying an angle a between at least two adjacent portions or sections of the directional drill.

[0035] According to one embodiment of the method according to the present invention, it comprises using an actuator that is exchangeable or adjustable to vary the dogleg setting of the directional drill.

[0036] In accordance with one embodiment of the method according to the present invention, it comprises using a push rod mechanism to apply a setting of the actuator on the deflection assembly.

[0037] According to one embodiment of the method according to the present invention, it comprises using a sliding block and a slot arrangement to control the adjust the deflection assembly.

[0038] In accordance with a further embodiment of the method according to the present invention, the method comprises exchanging the actuator or adjusting the actuator to enable different and discrete dogleg settings.

[0039] The DDDLAS and method according to the present invention seeks to address one or more of the known issues in the prior art. The present invention may address additional issues not expressly mentioned.

[0040] As mentioned above, the present invention is especially suitable for directional drills utilizing an inner assembly that is retrievable from the directional drill.

[0041] By using a DDDLAS and method according to the present invention a highly robust solution is provided.

[0042] Indeed, most of the prior art DDDLAS require the directional drill to be retrieved to the surface to adjust the dogleg setting / deflection angle. This is not a requirement of the present invention.

[0043] An advantage with the DDDLAS according to the present invention is that there is no need for making manual adjustments on the directional drill itself to achieve the desired dogleg setting.

[0044] The DDDLAS according to the present invention can be used for both setting the initial dogleg setting and for adjusting the dogleg setting at any time during a stop in the drilling operation.The DDDLAS according to the present invention is very versatile and may be easily optimized to the specific requirements of various directional drilling systems.

[0045] In addition to the above, the DDDLAS according to the present invention results in that the axial length of the directional drill becomes considerably shorter.

[0046] Another advantage with the DDDLAS according to the present invention, is that the directional drill may be thinner compared to prior art directional drills, which together with being shorter, will result in faster drilling times and easier handling.

[0047] Further preferable features and advantageous details of the present invention will appear from the following example description, claims and attached drawings.

[0048] Example

[0049] The present invention will below be described in further detail with references to the attached drawings, where:

[0050] Fig. la-b are principle drawings of a directional drill according to prior art,

[0051] Fig. 2a-d are principle drawings of a first embodiment of a directional drill dogleg adjustment system according to the present invention,

[0052] Fig. 3 is an exploded view of a directional drill dogleg adjustment assembly according to the present invention,

[0053] Fig. 4 is a principle drawing of a directional drill dogleg adjustment assembly according to an alternative embodiment,

[0054] Fig. 5a-b are principle drawings of one embodiment of a manipulator assembly according to one embodiment of the present invention,

[0055] Fig. 6a-c are principle drawings of an actuator according to one embodiment of the present invention,

[0056] Fig. 7a-c are principle drawings of a directional drill with a directional drill dogleg adjustment system according to the present invention with zero dogleg setting, andFig. 7d-f are principle drawings of a directional drill with a directional drill dogleg adjustment system according to the present invention with dogleg setting being larger than zero.

[0057] Reference is now made to Figures la-b illustrating an example of a prior art directional drill 10 that comprises numerous parts. The parts of the directional drill 10 will be described in order from the drill bit 20 end and upwards; a reamer 30, drive shaft connection assembly 40, a thrust bearing assembly 50, a lower outer tube 60, a deflection assembly 70, an upper outer tube 80, stabilizer assembly 90, rotation preventing device 100, an orientation measurement assembly 150 and a rear unit 200. In the shown embodiment the thrust bearing assembly 50, lower outer tube 60, deflection assembly 70, stabilizer assembly 90, rotation preventing device 100 and orientation measurement assembly 150 all form parts of a non-limiting example of the outer element 11 of the directional drill 10. In general, the outer element 11 contains all the parts that does not rotate during drilling, i.e. are directly / rotationally coupled to the rotation preventing device 100. The outer element 11 of a directional drill 10 may therefore comprise more or less parts than what is the case for the shown non-limiting embodiment. The outer element 11 being arranged to accommodate an inner directional drill drive shaft 110 that is directly or indirectly coupled to the rear unit 200 at one end and the drive shaft connection assembly 40 at the opposite end. The directional drill drive shaft 110 transfers rotational forces from a drill rig onto the drill bit 20, thereby driving the drill bit 20 during the drilling operation. The directional drill drive shaft 110 and any of its connection means positioned internally of the outer element 11, forms a part of the inner element 12 of the directional drill 10.

[0058] In the prior art directional drill 10 of Fig. la-b, the deflection assembly 70 is manually adjusted with the directional drill 10 topside to change the dogleg setting (deflection angle). The deflection assembly 70 is configured to bend the directional drill drive shaft 110 extending therethrough applying an angle to the drill bit 20.

[0059] Reference is now made to Fig. 2a-d showing principle drawings of a directional drill dogleg adjustment system (DDDLAS) 300 according to the present invention suitable for use in a directional drill 10. The DDDLAS 300 according the present invention enables adjustment of the dogleg setting of the directional drill enabling setting and adjustment of the deflection angle of a directional drill 10. The DDDLAS 300 according to the present invention comprises a dogleg setting control assembly (DLSCA) 400 configured to be housed in the direction drill 10. The DDDLAS 300 further comprises an inner assembly 700 configured for, from the surface, deployment into and retrieval from the directional drill 10 by a wireline while the directional drill 10 is in-situ. Other methods of deploymentand retrieval may be suitable. The inner assembly 700 comprising an actuator 800 releasably coupled at an axially distal end thereof.

[0060] In relation to the directional drill 10 of Fig. la-b, the DDDLAS 300 according to the present invention replaces the lower parts of the outer 11 and inner 12 elements of the directional drill 10, i.e. the parts shown in Fig. la-b, between the reamer 30 and rotation preventing device 100.

[0061] Reference is now, in addition to Fig. 2a-d, made to Fig. 3 showing an exploded view of the DLSCA 400 according to one embodiment of the present invention. Reference is also made to Fig.4 showing an alternative embodiment of the DLSCA 400 according to the present invention. The DLSCA 400 according to the present invention comprises a deflection assembly 500 and a manipulator assembly 600 accommodated in and connected to the deflection assembly 500, wherein the deflection assembly 500 and manipulator assembly 600 are configured for accommodating the directional drill drive shaft 110 and connection to the drill bit 20 and rear unit 200 of the directional drill 10. The deflection assembly 500 according to the present invention is configured to vary an angle a between at least two adjacent portions or sections of the directional drill 10. The manipulator assembly 600 is configured to receive the inner assembly 700 in-situ and varying the dogleg setting of the directional drill 10 according to the actuator 800 coupled to the inner assembly 700, further described below.

[0062] In accordance with the shown embodiment, the deflection assembly 500 comprises an elongated tubular body assembly 510 formed by a first (lower) 520 and second (upper) 530 elongated tubular bodies pivotably connected to each other at facing axial distal ends by a pivotable connection interface 540, enabling the first elongated tubular body 520 to be pivotable in relation to the second elongated tubular body 530, pivotable about a pivoting axis of the pivotable connection interface 540, and thus also the reamer 30 and drill bit 20. The pivoting axis is coinciding with a central transversal axis through the directional drill 10 at the pivotable connection interface 540.

[0063] The first elongated tubular body 520 is at first (lower) end 521 configured for connection to a drive shaft connection assembly 550 according to the present invention, further described below, and a second (upper) profiled end 522 configured to be received in the second elongated tubular body 530 and interaction with a first (lower) profiled end 531 thereof. The second elongated tubular body 530 is at the first profiled end 531 configured for accommodating the second profiled end 522 (upper part / end) of the first elongated tubular body 520 and at a second (upper) end 532 configured for connection to a first (lower) end of an elongated tubular manipulator body 610 of the manipulator assembly 600 according to the present invention, further described below.The mentioned profiled ends of the first 520 and second 530 elongated tubular bodies are in the shown embodiment in a preferred S-shaped configuration. However, alternative shapes may be preferable for specific conditions not expressly referenced.

[0064] The mentioned pivoting connection interface 540 is according to one embodiment of the present invention, arranged in connection with the curves of the profiled ends 522 and 531. In the shown embodiment, holes 541 are arranged diametrically opposite in connection with the lower points of the S-shaped profile of the second profiled end 522 of the first elongated tubular body 520. In the first profiled end 531 of the second elongated tubular body 530, through holes 542 are arranged diametrically opposite in connection with the higher points of the S-shaped profile of the second profiled end 522, such that when the first 520 and second 530 tubular bodies are joined via their S-shaped profiled ends, the mentioned through holes 542 coincide with the holes 541, and wherein bolts 543 can be inserted in the through holes 542 and holes 541, connecting the first 520 and second 530 elongated tubular bodies together and forming the mentioned pivoting connection interface 540. The mentioned S-shaped profiled ends 522 and 531, respectively, are formed such that there is clearance / gap, allowing the parts to pivot the desired angle within the shape of the profiles, further described below. Seals or O-rings will be arranged in connection with the mentioned S-profiled axial distal ends to seal the deflection assembly 500. In one embodiment the holes 541 and bolts 543 are threaded and configured for threaded engagement with each other. In one embodiment bolts 543 or similar members may be integrally formed within the first tubular body 520.

[0065] The deflection assembly 500 further comprises a linear piston assembly 560 comprising an elongated tubular piston body 561 configured to be accommodated and movable axially in the second elongated tubular body 530. The linear piston assembly 560 is further configured for sliding interaction with the first elongated tubular body 520 to affect the pivoting angle a thereof, i.e. the dogleg setting. To achieve this sliding interaction, the first elongated tubular body 520 is provided with a pair of elongated members 523, wherein each of the pair of elongated members 523 is pivotably coupled at a first end proximal the second profiled end 522. The elongated members 523 are protruding axially and laterally reversed from the second profiled end 522 thereof, with the axial center axis coinciding with the mentioned threaded holes 541.

[0066] In accordance with the embodiment of Fig. 3, the elongated tubular piston body 561 is further provided with a slot arrangement formed by corresponding axially extending elongated angled slots 562, angled in relation to the horizontal plane of the elongated tubular piston body 561. Thementioned angle is typically smaller than 10 degrees, more preferably smaller than 6 degrees and even more preferable smaller than 3 degrees.

[0067] In the embodiment of Fig. 3, the mentioned elongated members 523 are operably connected at a second end with a sliding block 544 operable in sliding engagement with / constrained within the mentioned angled slots 562. This configuration allows the elongated members 523 to pivot some in relation to the angled slot 562. In this manner, as the linear piston assembly 560 moves axially in the second body 530 towards the first elongated tubular body 520 this applies an increasing pivoting angle on the first elongated tubular body 520, pivoting the first elongated tubular body 520 in relation to the second elongated tubular body 530, the pivoting angle depending on the axial length the linear piston assembly 560 moves, as will be further described below.

[0068] In Fig. 4 is shown an alternative embodiment of the sliding interaction between the linear piston assembly 560 and the pair of elongated members 523 of the first elongated tubular body 520. In this embodiment, the pair of elongated members 523 are provided with internally elongated angled slots 545, corresponding to the elongated angled slots 562 of the embodiment of Fig. 3, and wherein the piston body 561 is provided with a respective slide block 563 fixed at exterior side thereof, the slide block 563 being configured to be accommodated in the mentioned respective internally elongated angled slots 545 and movable in axial direction thereof. In this manner, as the linear piston assembly 560 moves axially in the second elongated tubular body 530 towards the first body elongated tubular 520 this applies an increasing pivoting angle on the first elongated tubular body 520 in relation to the second elongated tubular body 530, the pivoting angle depending on the length the linear piston assembly 560 moves / is moved, similarly as in the embodiment of Fig. 3, as will be further described below.

[0069] In accordance with one embodiment of the deflection assembly 500 according to the present invention, it further comprises a pretension device 570 connected between the first elongated tubular body 520 and the linear piston assembly 560 providing a biasing force returning the linear piston assembly 560 to initial position where the pivoting angle of the first elongated tubular body 520 in relation to the second elongated tubular body 530 is zero, and thus also the dogleg setting / deflection angle a of the directional drill 10 / drill bit 20 is zero. The pretension device 570 according to the present invention comprises at least one spring 571 or an assembly of springs 571. In the shown embodiments, the pretension device 570 comprises four springs 571 distributed in circumferential direction of the first 520 and second 530 elongated tubular bodies and the elongated tubular piston body 561. The first elongated tubular body 520 and the elongated tubular piston body 561 are provided with spring fixation interfaces 572, such as recesses or slots, configured toaccommodate and retain the ends of the springs 571. The skilled person would understand that varying configurations and numbers of the springs 571 and spring fixation interfaces 572 could be used.

[0070] The linear piston assembly 560 is, on the opposite side of where the pretension device 570 connected, i.e. the side of the elongated tubular piston body 561 facing away from the first elongated tubular body 520, provided with a thrust bearing 580, configured for engagement with a linear sliding rotor 660 of the manipulator assembly 600, further described below. The thrust bearing 580 is preferably provided with wear resistant members, such as Polycrystalline bits or similar, at the engagement side with the linear sliding rotor 660.

[0071] Reference is now also made to Fig. 5a-b showing details of an embodiment of the manipulator assembly 600 according to the present invention. The manipulator assembly 600 according to one embodiment of the present invention is configured to be accommodated in the deflection assembly 500. The manipulator assembly 600 comprises an elongated tubular manipulator body 610 configured to be accommodated and fixed in the second elongated tubular body 530. The elongated tubular manipulator body 610 has a first end 611 facing the first elongated tubular body 520 and a second end 612 facing the opposite direction. The interior of the elongated tubular manipulator body 610 is divided in a first interior section 613 extending axially a first distance from the first end 611 and a second interior section 614 extending axially a second distance from the second end 612, the first 613 and second 614 interior sections being separated by a solid section 615, further described below.

[0072] The first interior section 613 has in the shown embodiment, a stepped interior circumference extending axially from the first end 611 with a stepped decreasing interior circumference. The stepped interior circumference is formed by a first interior circumference in a first axial part 613a from the first end 611, followed by a second interior circumference in a second axial part 613b of the first interior section 613, the second interior circumference of the second axial part 613b being smaller than the first interior circumference, and further followed by a third interior circumference in a third axial part 613c, the third interior circumference of the third axial part 613c being smaller than the second interior circumference, further described below. In an alternative embodiment, the first interior section 613 has only one interior circumference.

[0073] The manipulator assembly 600 further comprises a push rod mechanism 620. Moreover, in the shown embodiment, the mentioned second interior section 614 has a uniform interior circumference and provides a stroke volume for the push rod mechanism 620, further describedbelow. The push rod mechanism 620 is in the shown embodiment formed by drive shaft adapter 630 having first 631 and second 632 axial parts provided with respective exterior threads 633 and 634. The second axial distal part 632 is configured for indirectly coupling the rear unit 200 of the directional drill 10 to the directional drill drive shaft 110 via the elongated tubular manipulator body 610, further described below. The first axial part 632 is configured for fixation of the drive shaft adapter 630 to the second axial distal end 532 of the second elongated tubular body 530 of the deflection assembly 500 by means of an elongated tubular rear bearing adapter 650, further described below.

[0074] In accordance with one embodiment of the present invention, as shown in Fig. 3, the second elongated tubular body 530 is provided with interior threads (not shown) and the elongated tubular rear bearing adapter 650 is provided with corresponding exterior threads 651 at a first axial end 652 of an elongated tubular adapter body 653 thereof, for mutual engagement.

[0075] In accordance with one embodiment of the present invention, the elongated tubular rear bearing adapter 650 is provided with interior threads 654 at a second axial end 655 corresponding to the exterior threads 634 of the drive shaft adapter 630 for mutual engagement.

[0076] Referring to Fig. 5a and 5b, the second axial part 632 of the drive shaft adapter 630 has a smaller interior and exterior circumferences than the first axial part 631. The transition from the larger interior and exterior circumferences to the smaller interior and exterior circumferences are preferably formed by a respective inclined and exterior surface.

[0077] The push rod mechanism 620 further comprises push rod plunger 640 having a first axial part 641 with a first exterior circumference adapted to the interior circumference of the first axial part 631 of the drive shaft adapter 630 and a second axial part 642 with a second exterior circumference adapted to the interior circumference of the second axial part 632 of the drive shaft adapter 630. The transition from the larger exterior circumference to the smaller exterior circumference is preferably formed by an inclined surface corresponding to the inclined interior surface of the drive shaft adaptor 630.

[0078] The first axial part 641 is at the end thereof provided with an annular flange 643 adapted the interior circumference of the elongated tubular drive manipulator body 610, and wherein the axial length of the first axial part 641 of the push rod plunger 640 corresponds to the axial length of the first axial part 631 of the drive shaft adapter 630. The axial length of the second axial part 642 is longer than the axial length of the second axial part 632 of the drive shaft adapter 630, such that the push rodplunger 640, when accommodated in the drive shaft adapter 630 protrudes out of the second axial part 632 with a distance in in itial / u nloaded position / state.

[0079] Accordingly, the mentioned second interior section 614 of the manipulator assembly 600 provides a stroke volume / length of stroke for the push rod mechanism 620 / push rod plunger 640, further described below. The push rod mechanism 620 further comprises an interior drive shaft connection 644, such as a spline connection or bushing configured to rotationally and axially fixate the directional drill drive shaft 110 to the elongated tubular drive manipulator body 610 of the manipulator assembly 600.

[0080] The push rod mechanism 620 further comprises a linear sliding rotor 660 configured to be accommodated in the first interior section 613 of the elongated tubular manipulator body 610. The linear sliding rotor 660 is provided with axial recesses 661 at the exterior surface thereof and the elongated tubular manipulator body 610 is provided with corresponding axially extending members 663 at interior surface of the first interior section 613 rotationally locking the linear sliding rotor 660 to the elongated tubular manipulator body 610 while allowing the linear sliding rotor 660 to move axially therein.

[0081] The mentioned linear sliding rotor 660 is further provided with a through hole in the center thereof allowing the directional drill drive shaft 110 to extend therethrough, further described below. Accordingly, the linear sliding rotor 660 rotates with the directional drill drive shaft 110 and elongated tubular manipulator body 610, while being axially movable in relation to the same. The liner sliding rotor 660 is configured for engagement with the linear piston assembly 560. The linear sliding rotor 660 is preferably at the engaging side provided with Polycrystalline bits or similar corresponding to the thrust bearing 580 of the deflection assembly 500.

[0082] In accordance with the shown embodiment of the present invention, the push rod mechanism 620 further comprises multiple push rods 645 arranged axially movable in axially extending through holes 646, extending between the first 613 and second 614 interior sections, and configured for engagement with the mentioned annular flange 643 of the push rod plunger 640 at one end and the linear sliding rotor 660 at the other end.

[0083] Accordingly, when the push rod plunger 640 is moved axially in the second interior section 614, the push rods 645 push on the linear sliding rotor 660 acting as a piston in the deflection assembly 500 by acting on the linear piston assembly 560 and moving the latter axially in the second elongated tubular body 530 affecting the pivoting angle of the first elongated tubular body 520 transforming the axial movement to a dogleg setting / deflection angle a of the drill bit 20, further described below.In accordance with one embodiment of the present invention, the push rod mechanism 620 further comprises a pretension device 647 comprising at least one spring 648 or assembly of springs 648 arranged in the stroke volume in the second interior section 614, between the solid section 615 and the push rod plunger 640 to provide a biasing force on the push rod plunger 640 returning the push rod plunger 640 to an initial position, i.e. where the push rod plunger 640 is situated in the drive shaft adapter 630 and in upper position / unloaded position.

[0084] The mentioned elongated tubular adapter body 653 of the elongated tubular rear bearing adapter 650 is configured to accommodate the upper parts of the drive shaft adapter 630. The elongated tubular rear bearing adapter 650 is further provided with a stator 656 axially and rotationally fixed in the elongated tubular adapter body 653, at rear (upper) part thereof. The elongated tubular rear bearing adapter 650 further comprises a rotor 657 rotationally fixed to the drive shaft adapter 630 and axially fixed in the elongated tubular adapter body 653. The mentioned stator 656 and rotor 657 are provided with a through hole through which the second axial part 632 of the drive shaft adapter 630 extends, and wherein the mentioned threads 634 and 654 are positioned axially outside the stator 656 and rotor 657. Accordingly, the elongated tubular rear bearing adapter 650 axially locks the manipulator assembly 600 in the directional drill 10, while allowing the manipulator assembly 600 to rotate in the directional drill 10.

[0085] The mentioned manipulator assembly 600 is thus configured to be received and accommodated in the deflection assembly 500 such that the linear sliding rotor 660 is in engagement with the thrust bearing 580 at the upper end of the linear piston assembly 560, and wherein the directional drill drive shaft 110, when the manipulator assembly 600 is accommodated in deflection assembly 500, extends from the push rod mechanism 630, through the deflection assembly 500 and is connected to the drill bit 20 via a drive shaft connection assembly 550 connected between the drill bit 20 and the lower end of the directional drill drive shaft 110. The mentioned drive shaft connection assembly 550 is connected to the directional drill drive shaft 110 by means of a front lock pin 551.

[0086] Accordingly, in the present invention, the dogleg setting / deflection angle a of the drill bit 20 provided by the deflection assembly 500 will change depending on the stroke length / axial movement applied to the manipulator assembly 600 by the inner assembly 700 with the actuator 800 in engagement with the second axial part 642 of the push rod plunger 640.

[0087] To be able to adjust the dogleg setting / deflection angle a of the deflection assembly 500, the DDDI.AS 300 makes use of the actuator 800, as shown in Fig. 6a-c, releasably coupled to the inner assembly 700. The actuator 800 comprises an elongated tubular body 810 which at a first (upper)end provided with an inner assembly connection 820 configured for connection to an end of the inner assembly 700. The inner assembly 700 per se is well known for a skilled person and requires no further description herein. The actuator 800 is at a second (lower) end provided with an exchangeable linear portion 830, that in the shown embodiment is formed by a push rod plunger connection. In accordance with one embodiment of the present invention, the push rod plunger connection 830 is exchangeable by means of a quick lock / snap device 840 integrated in the elongated tubular body 810. E.g. the elongated tubular body 810 is provided with an axially extending recess or slot 821 at the second axial end and the quick lock snap device 840 is associated with the mentioned recess or slot 821. The mentioned recess or slot 821 is configured to receive an upper axial profiled end 831 of the push rod plunger connection 830. The upper axial profiled end 831 of the push rod plunger connection 830 is e.g. provided with an exterior circumferential locking recess 832 and the quick lock / snap device 840 comprises at least one arm 841 provided with a locking member 842 configured for engagement with the mentioned locking recess 832 and retaining the push rod plunger connection 830 to the elongated tubular body 810. By arranging the mentioned at least one locking arm 841 movable between a locking position, where the locking member 842 is in engagement with the locking recess 832, and an unlocking position, where the locking member 842 is moved out of engagement with the locking recess 832 and the push rod plunger connection 830 is free to be retrieved from the mentioned recess 832 to be replaced with a push rod plunger connection 830 with different properties corresponding to different and discrete dogleg settings.

[0088] By arranging the mentioned at least one arm to a pretension device 843 it is ensured that the locking member 842 is held in locking position and in engagement with the locking recess 832 with a biasing force ensuring that the push rod plunger connection 830 is secured to the actuator 800.

[0089] The push rod plunger connection 830 is at the other side configured for engagement with the upper (free) end of the second axial part 642 of the push rod plunger 640.

[0090] In accordance with the present invention, the push rod plunger connections 830 will have different properties and designed lengths to alter the stroke length of the manipulator assembly 600 and thus the axial movement of the linear piston assembly 560 and thus also the dogleg setting / deflection angle a of the drill bit 20, further described below. The longer the length of the push rod plunger connection 830 is, the longer the stroke length is and the longer the linear piston assembly 560 moves and the larger change in dogleg setting / deflection angle a is achieved for the drill bit 20 via the pivoting angle of the first elongated tubular body 520 in relation to the second elongated tubular body 530.In accordance with an alternative embodiment of the actuator 800, the actuator is adjustable in axial length, enabling the use of the same adjustable actuator 800 for different and discrete dogleg settings. One enablement is to make the actuator 800 telescopic or otherwise length adjustable. In accordance with one possible embodiment, the actuator 800 comprises a linear actuator (not shown) configured to adjusting the axial position of the linear portion / push rod connection 830 in axial direction of the actuator 800. According to a further embodiment, the linear actuator is remotely controllable, enabling remote controlling of the settings / length of the actuator 800.

[0091] Reference is now further made to Fig. 7a-c showing the directional drill 10 with dogleg setting / deflection angle a = 0 degrees and Fig. 7d-f showing the directional drill 10 with a dogleg setting / deflection angle a that is larger than zero and e.g. 1.1 degrees by using the longest push rod connection 830 as shown in Fig. 6c. However, the push rod connections 830 may be longer than the shown examples in Fig. 6c. How the dogleg setting / deflection angle a of a direction drill 10 with the DDDLAs 300 according to the present invention works will now be described.

[0092] The desired dogleg setting / deflection angle a is decided and the proper push rod plunger connection 830 is arranged to the actuator 800 and the actuator 800 is arranged to the inner assembly 700 topside.

[0093] The inner assembly 700 is next deployed into the directional drill 10 and pumped into connection with the manipulator assembly 600, wherein the inner assembly 700 via the actuator 800 engages the push rod mechanism 630 and axially moves / pushes on the push rod plunger 640. The push rod plunger 640 actuates the push rods 645 that again pushes on the linear sliding rotor 660 which is in engagement with the linear piston assembly 560 and correspondingly moves this axially. As the linear piston assembly 560 moves axially, the sliding block 544, as shown in Fig. 3, moves in the angled slots 562, resulting in that the elongated members 523 apply a pivoting angle on the first elongated tubular body 520 in relation to the second elongated tubular body 530 which applies a dogleg setting / deflection angle a to the drill bit 20. Accordingly, the axial movement is transferred to dogleg setting / deflection angle a on the drill bit 20. The drilling may thus be performed with the desired dogleg setting / deflection angle a.

[0094] When a different dogleg setting / deflection angle a is required, the inner assembly 700 is retrieved to the surface / topside and the push rod plunger connection 830 of the actuator 800 is exchanged with a push rod plunger connection 830 with a different length / properties corresponding to the desired dogleg setting / deflection angle a, before the inner assembly 700 again is deployed into the directional drill 10 and pumped into engagement with the manipulator assembly 600, as describedabove. In the alternative embodiment with an adjustable actuator 800, the axial length of the actuator 800 is adjusted corresponding to the desired dogleg setting / deflection angle a, before the inner assembly 700 again is deployed into the directional drill 10 and pumped into engagement with the manipulator assembly 600. The drilling can then be started again with a different dogleg setting / deflection angle a.

[0095] Accordingly, the longer the axial length of the actuator 800, the longer the linear piston assembly 560 is moved axially towards the drill bit 20, and the larger change in the dogleg setting / deflection angle a for the drill bit 20 is achieved.

[0096] Accordingly, the DDDLAS 300 according to the present invention makes use of small angle movements to achieve the dogleg setting / deflection angle a for the drill bit 20.

[0097] The pretension devices 570 and 647 are retaining the DLSCA 400 in an initial / non-adjusted position by a biasing force that is overcome by the inner assembly 700 with the actuator 800 engaging the manipulator assembly 600 and linear piston assembly 560 of the deflection assembly 500. Accordingly, when the inner assembly 700 is removed from the directional drill 10, the dogleg setting / deflection angle a will return to zero.

[0098] Accordingly, the inner assembly 700 during drilling will apply a desired dogleg setting / deflection angle a to the directional drill 10, that easily can be changed by retrieving the inner assembly 700 from the directional drill 10 and changing the properties of the actuator 800 thereof before continuing the drilling with a different dogleg setting / deflection angle a.

[0099] Accordingly, by the DDDLAS 300 according to the present invention is provided a mechanical solution that does not require any external locking system to hold the dogleg setting / deflection angle a of the deflection assembly 500 / directional drill 10.

[0100] Further, the DDDLAS 300 according to the present invention makes use of long and low angled slots 562, 545 that self-locks the dogleg setting / deflection angle a of the deflection assembly 500 / directional drill 10 during drilling.

[0101] The technical features of the above described embodiments may be combined to form modified embodiments within the scope of the attached claims.

Claims

Claims1. A directional drill dogleg adjustment system (300) suitable for use in a directional drill (10), wherein the directional drill dogleg adjustment system (300) comprisesa dogleg setting control assembly (400) housed in the directional drill (10), andan inner assembly (700) comprising an actuator (800) releasably coupled at an axial distal end thereof, the inner assembly (700) being configured for, from the surface, deployment into and retrieval from the directional drill (10) while the directional drill (10) is in-situ,wherein the inner assembly (700) is configured, when deployed into the directional drill (10), to engage and actuate the dogleg setting control assembly (400) to adjust a dogleg setting of the directional drill (10) in-situ.

2. The directional drill dogleg adjustment system (300) of claim 1, wherein the dogleg setting control assembly (400) comprises a deflection assembly (500) configured to vary an angle (a) between at least two adjacent portions or sections of the directional drill (10) and a manipulator assembly (600) configured to receive the inner assembly (700) in-situ and varying the dogleg setting of the directional drill (10) according to the actuator (800).

3. The directional drill dogleg adjustment system (300) of claim 2, wherein the manipulator assembly (600) comprising a push rod mechanism (620) configured to be axially movable in the dogleg setting control assembly (400) to apply a setting of the actuator (800) on the deflection assembly (500).

4. The directional drill dogleg adjustment system (300) of claim 2, wherein the deflection assembly (500) comprises a pair of elongated members (523), each of the pair of elongated members (523) being pivotably coupled at a first axial distal end in the directional drill (10) and operably connected at a second axial distal end with a sliding block (544, 563) and a slot arrangement wherein the sliding block (544, 563) is constrained within an angled slot (562, 545) extending axially towards a proximal end of the directional drill (10) such that the deflection assembly (500) is configured by adjusting the position of the sliding block (544, 563) within the angled slots (562, 545).

5. The directional drill dogleg adjustment system (300) of any one of claims 1 to 4, wherein the inner assembly (700) is configured for releasably coupling one of a plurality of actuators (800), each of the plurality of actuators (800) corresponding to a different and discrete dogleg setting, or an adjustable actuator (800) enabling the use of the same adjustable actuator (800) for different and discrete dogleg settings.

6. The directional drill dogleg adjustment system (300) of claim 5, wherein each of the plurality of actuators (800) is provided with a linear length differing from each of the other of the plurality of actuators (800) configured for engaging with the inner assembly (700) for operating the dogleg setting control assembly (400) to adjust the dogleg setting for a distinct dogleg setting, or the adjustable actuator (800) is adjustable in axial length for engaging with the inner assembly (700) for operating the dogleg setting control assembly (400) to adjust the dogleg setting for a distinct dogleg setting.

7. The directional drill dogleg adjustment system (300) according to claim 6, wherein the actuator (800) comprises a substantially linear portion (830) such that the distinct dogleg setting corresponds to the substantially linear portion (830) of a respective one of the plurality of actuators (800).

8. A method of adjusting a dogleg setting of a directional drill dogleg adjustment system (300) in a directional drill (10), the method comprising:providing a dogleg setting control assembly (400) within a directional drill (10) having an inner assembly (700) being configured for, from the surface, deployment into and retrieval from the directional drill (10) while the directional drill (10) is in-situ;retrieving the inner assembly (700) from the directional drill (10) to the surface;coupling one of a plurality of actuators (800) with the inner assembly (700) of the dogleg setting control assembly (400), wherein the coupled actuator (800) comprises a linear portion (830) associated with a desired dogleg setting; anddeploying the inner assembly (700) with the coupled actuator (800) in the directional drill (10) in-situ to engage a manipulator assembly (600) which in turn operates a deflection assembly (500) of the dogleg setting control assembly (400) to set a desired dogleg setting of the directional drill (10).

9. The method according to claim 8, comprising varying an angle (a) between at least two adjacent portions or sections of the directional drill (10).

10. The method according to claims 8-9, comprising using an actuator (800) that is exchangeable or adjustable to vary the dogleg setting of the directional drill (10).

11. The method according to claim 10, comprising using a push rod mechanism (620) to apply a setting of the actuator (800) on the deflection assembly (500).

12. The method according to claim 10, comprising using a sliding block (544, 563) and a slot arrangement to control the adjust the deflection assembly (500).

13. The method according to claim 11, comprising exchanging the actuator (800) or adjusting the actuator (800) to enable different and discrete dogleg settings.

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