A TOP DRIVE WELL DRILLING INSTALLATION

20180298693 ยท 2018-10-18

Assignee

Inventors

Cpc classification

International classification

Abstract

The present invention relates to a top drive well drilling installation comprising a trolley guided along one or more vertical rails along the drilling tower, which trolley is provided with a support frame supporting the top drive unit and a rotating head-clamp. The rotating headclamp comprises an open-centered rotary body defining a pipe passage; a thrust bearing supporting the rotary body; and multiple mobile pipe retainers supported by the rotary body providing an operative and a non-operative position allowing passage of a pipe and engagement below a shoulder of a pipe of the drill string so as to suspend said drill string therefrom. At least the tubular stem is vertically movable relative to the rotating headclamp between an upper remote position allowing the engagement of a pipe of the drill string by the rotating headclamp and a lower connection position allowing the attachment of the tubular stem with the pipe.

Claims

1. A top drive well drilling installation comprising: a drilling tower; a top drive unit including a tubular stem which is to be connected to an upper end of a drill string for rotation therewith about an axis of the drill string, and a motor adapted to rotate the tubular stem and thereby the connected drill string; one or more vertical rails supported by the drilling tower; a trolley guided along said one or more vertical rails, which trolley is provided with a support frame supporting the top drive unit, at least so as to absorb reaction torque from the motor of the top drive unit; a hoisting device for moving the trolley up and down; and a rotating headclamp comprising: an open-centered rotary body defining a pipe passage in line with a drill string axis to allow passage of a pipe of the drill string; a thrust bearing supporting the rotary body, allowing rotation thereof; and multiple mobile pipe retainers supported by the rotary body so as to provide an operative and a non-operative position of the rotating headclamp, the pipe retainers being adapted toin the non-operative positionallow passage of a pipe of the drill string through the pipe passage andin the operative positionengage below a shoulder of the pipe of the drill string extending through the pipe passage so as to suspend said drill string therefrom; wherein the support frame is adapted to support the rotating headclamp and absorb the load of the suspended drill string, and wherein at least the tubular stem is vertically movable relative to the rotating headclamp between an upper remote position allowing the engagement of a pipe of the drill string by the rotating headclamp and a lower connection position allowing the attachment of the tubular stem with the pipe of the drill string while the pipe and/or the drill string is supported by the rotating headclamp.

2. The top drive well drilling installation according to claim 1, wherein the mobile pipe retainers have a clamping jaw to engage on a pipe.

3. The top drive well drilling installation according to claim 1, wherein two sets of multiple mobile pipe retainers are provided, each set adapted to retain a different type of pipe, and wherein it is possible to have one set in the non-operative position and the other in the operative position.

4. The top drive well drilling installation according to claim 1, wherein the mobile pipe retainer is embodied as a lever comprising an arm and a fulcrum, which fulcrum is fixed to the rotary body and wherein one end of the arm is adapted toin the operative positionengage on the pipe, and in the non-operative position has cleared the area in line with the pipe passage to allow the passage of a pipe of the drill string, and wherein the other end of the arm is operable by an actuator to move the opposite end of the arm between the operative and the non-operative position.

5. The top drive well drilling installation according to claim 1, wherein the rotary body is embodied as a cylinder with a flanged top end supporting the mobile pipe retainers and wherein the thrust bearing supports the flanged top end of the rotary body.

6. The top drive well drilling installation according to claim 1 wherein the rotating headclamp comprises a housing supporting the rotating headclamp, which housing is supported by the support frame.

7. The top drive well drilling installation according to claim 1, wherein in the remote position of the tubular stem the rotating headclamp is removable from the support frame.

8. The top drive well drilling installation according to claim 1, wherein the support frame furthermore supports a centralizer below the rotating headclamp to centralize the drill string.

9. The top drive well drilling installation according to claim 1, wherein the rotating headclamp is translatably supported in the support frame between an operative position in line with the drill string axis and a parking position remote from the drill string axis.

10. The top drive well drilling installation according to claim 1, wherein the support frame supports a wrench device for making and breaking connections between the tubular stem and the drill string.

11. The top drive well drilling installation according to claim 1, wherein the hoisting device comprises a cable and a winch, a crown block, and a travelling block suspended from the crown block by said cable, wherein support frame is suspended from the crown block so as to move up and down upon operation of the winch.

12. The top drive well drilling installation according to claim 1, wherein the support frame is provided with a mud hose connector.

13. A method for performing a well drilling operation, comprising the step of using the installation according to claim 1.

14. The method according to claim 13, for the assembly of a drill string, comprising the steps of: providing the tubular stem in the upper remote position; providing the mobile pipe retainers of the rotating headclamp in the non-operative position; providing a pipe of a drill string, having a shoulder, upwards through the pipe passage of the rotating headclamp; moving the pipe retainers to the operative position to engage below the shoulder of the pipe extending through the pipe passage, so as to suspend said pipe and/or drill string therefrom; and moving the tubular stem relative to the rotating headclamp to the lower connection position and attaching the tubular stem with the pipe while the pipe and/or drill string is supported by the rotating headclamp.

15. The method according to claim 13, wherein a substitute rotating headclamp is provided, comprising the steps of: providing the tubular stem in the upper remote position; removing the rotating headclamp from the support frame; and providing the substitute rotating headclamp in the support frame.

16. The method according to claim 13, wherein the top drive unit is detachable from the support frame, comprising the following steps: well drilling by the top drive unit; detaching the drill string from the tubular stem while remaining supported by the rotating headclamp; detaching the top drive unit from the support frame; and tripping the drill string.

Description

[0076] The invention is further explained in relation to the drawings, in which:

[0077] FIG. 1 shows an embodiment of a top drive well drilling installation in a perspective view;

[0078] FIG. 2 shows an exemplary trolley of a top drive well drilling installation in a perspective view;

[0079] FIG. 3 shows the trolley of FIG. 2 in a side view;

[0080] FIG. 4 shows an schematic trolley of a top drive well drilling installation with a portion of a drill string in a side view;

[0081] FIGS. 5a and 5b show an exemplary embodiment of a rotating headclamp in side view;

[0082] FIG. 6a shows an embodiment of a rotating headclamp in top view;

[0083] FIG. 6b shows the rotating headclamp of FIG. 6a in a perspective top view;

[0084] FIG. 6c shows the rotating headclamp of FIG. 6a in a side view;

[0085] FIGS. 7a and 7b show respectively a front view and a side view of an embodiment of a trolley;

[0086] FIGS. 8a-8f show an embodiment of a pipe positioning motion arm supported by the trolley in various positions allowing the passage of a pipe of the drill string through the pipe passage of the rotating headclamp;

[0087] FIG. 9 shows in a perspective view a trolley and top drive unit of an alternative embodiment of a top drive well drilling installation,

[0088] FIG. 10 shows in a side view the trolley and top drive unit of the installation of FIG. 9,

[0089] FIGS. 11a-11c shown an alternative embodiment of a pipe positioning device supported by the trolley in various positions allowing the passage of a pipe of the drill string through the pipe passage of the rotating headclamp.

[0090] In FIG. 1 a top drive well drilling installation 1 according to the present invention is shown in a perspective view. A drilling tower 10 as is known from the previous applications of the same applicant and as commercially available is shown. The drilling tower 10 supports two vertical rails 11a, 11b. A trolley 12 is guided along said vertical rails 11a, 11b, here via guide wheel sets 13. This is shown in more detail in FIGS. 2-4.

[0091] The top drive well drilling installation 1 is furthermore provided with a top drive unit 30 including a tubular stem 31 to be connected to the upper end 51 of a drill string 50, visible in FIGS. 4 and 5 for rotation therewith about an axis A of the drill string, and including a motor 32 adapted to rotate the tubular stem 31 and thereby the connected drill string.

[0092] The trolley 12 is provided with a support frame 45 supporting the top drive unit, at least so as to absorb reaction torque from the motor of the top drive unit. In the shown embodiment, the top drive unit 30 is movably supported in the support frame 45 in a direction D, via actuators 33, between an upper remote position allowing the engagement of a pipe by a rotating headclamp 40 (explained below) and a lower connection position allowing the attachment of the tubular stem 31 with the pipe while the pipe and/or the drill string is supported by the rotating headclamp 40. In FIG. 4, schematically trolleys 33a are visible, provided on top drive unit 30, which may engage on rails provided in the support frame 45 to move the top drive unit 30 in direction D.

[0093] According to a preferred embodiment of the invention, the top drive unit 30 is movable upwards to such an extent that it is remote from the rotating headclamp 40, wherein in this remote position of the top drive unit 30 the rotating headclamp 40 is removable from the support frame 45.

[0094] The top drive well drilling installation 1 is furthermore provided with a hoisting device 20 for moving the trolley 12 up and down. The hoisting device comprises a winch, not visible, and a cable 21 extending from the winch, via one or more pulleys 23 at the top of the drilling tower 10 to a crown block 24 and a travelling block 25. The crown block comprises multiple sheaves, mounted on a common axle. The travelling block 25 is suspended from the crown block 24 by said cable 21. In the embodiment shown in FIG. 1, the support frame 45 is suspended from the travelling block 25 via connectors at the ends of the travelling block so as to move up and down upon operation of the winch. In the embodiment of FIGS. 2 and 3, the travelling block 25 is integrated into the support frame 45. Hence, the support frame 45 is suspended from the crown block 24 so as to move up and down upon operation of the winch.

[0095] The support frame 45 additionally supports a rotating headclamp 40, shown in detail in FIGS. 5a and 5b. The rotating headclamp 40 comprises: [0096] an open-centered rotary body 41 defining a pipe passage 41a in line with a drill string axis A to allow passage of a pipe of the drill string; [0097] a thrust bearing 43 supporting the rotary body 41, allowing rotation thereof; [0098] multiple mobile pipe retainers 42 supported by the rotary body 41 so as to provide an operative and a non-operative position of the rotating headclamp.

[0099] In the shown embodiment, the rotating headclamp comprises a housing 49 supporting the thrust bearing 43, which housing is supported by the support frame 45. Alternatively, the support frame 45 supports the rotating headclamp 40 directly, e.g. via the thrust bearing 43. Either way, the support frame 45 absorbs the load of the suspended drill string.

[0100] Possibly, the support frame 45 is adapted to support more than one rotating headclamp, i.e. a substitute rotating headclamp.

[0101] Possibly, a rotating headclamp 40 is translatably supported in the support frame 45 between an operative position in line with the drill string axis A and a parking position. Thus, the drill string axis can be cleared of the rotating headclamp if so desired. In addition, it is possible to have a support frame 45 comprising two rotating headclamp which can be positioned in line with the drill string axis A as desired.

[0102] Here, the rotary body is embodied as a cylinder 41b with a flanged top end 41a supporting the mobile pipe retainers 42. The thrust bearing 43 supports the flanged top end 41a of the rotary body.

[0103] Furthermore, in the shown embodiment, an additional bearing 44 is provided at the bottom end of the rotary body 41. A bearing connection 49a, which is a static frame part optionally integrated with housing 49, connects the thrust bearing 43 at the upper side of the open-centred rotary body with bearing 44 at the bottom end thereof.

[0104] In the shown embodiment, the support frame furthermore supports a centralizer 52 below the rotating headclamp to centralize the drill string. Such centralizers are known in the art.

[0105] Furthermore, the support frame supports a wrench device 56, for making and breaking connections between the tubular stem 31 and the drill string 50.

[0106] Pipe retainers 42 are movable between a non-operative position and an operative position. In the non-operative position (not shown) the pipe retainers 42 allow passage of a pipe of the drill string through the pipe passage 41a. In the operative position as shown in FIG. 5a, the pipe retainers 42 engage below a shoulder 51a at the upper end 51 of a pipe of the drill string 50 extending through the pipe passage 41a so as to suspend said drill string therefrom.

[0107] In FIG. 5b, an operative position is shown in which the pipe retainers engage below a shoulder 151a at the upper end 151 of a of a tool 150, here a casing tool 150, e.g. including an internal and/or external gripper assembly for gripping casing or a casing running tool. This tool is advantageously driven by the top drive. In the shown embodiment, the tool is connected to the tubular stem 31, which is also referred to as rotary stem or quill. At the bottom end, casing tool 150 comprises a casing engaging part 152 to engage on casing 155.

[0108] In the shown embodiment, the mobile pipe retainers 42 have a clamping jaw 42a to engage on a pipe or tool, which is preferably an exchangeable clamping jaw to be able to match the diameter and/ or shape to the type of pipe or tool.

[0109] In FIG. 6 a possible embodiment of a rotating headclamp is shown in top view, a perspective top view and a side view respectively. This rotating headclamp is provided with two sets each three mobile pipe retainers 42 and 42 respectively. Each set is adapted to retain a different type of pipe. This is advantageous as it is possible to have one set in the non-operative position and the other in the operative position.

[0110] The mobile pipe retainers 42, 42 of FIGS. 5a and 5b and FIG. 6 are embodied as a lever comprising an arm and a fulcrum, which fulcrum 42c is fixed to the rotary body, here flange 41a. One end 42a of the arm is adapted toin the operative positionengage on the pipe. Here, this end 42a of the arm is provided with clamping jaws 42d. In the non-operative position has cleared the area in line with the pipe passage to allow the passage of a pipe of the drill string. The other end 42b of the arm is operable by an actuator 46 to move the opposite end of the arm between the operative and the non-operative position. Here, the actuator 46 is embodied as a hydraulically operable finger engaging on the arm end 42b.

[0111] In FIGS. 7a and 7b respectively a front view and a side view of an embodiment of a trolley 212 with frame 245 is shown. Same parts are given same reference numerals to which 200 has been added. In embodiments, it is required to transfer mud via a mud hose 280 to the top drive unit 230. To this end, a mud connector 282 is provided on the top drive unit 230. Top drive unit 230 comprises a tubular stem 231. In the shown embodiment, also a wrench device 254 is visible.

[0112] According to a preferred aspect of the invention, mud hose 280 is connected to support frame 245 via a mud hose connector 281. Similarly, other supply lines for electronics, control signals and hydraulics may also be connected to support frame 245 alone, e.g. via a drag chain or the like. The electronics, control signals, hydraulics and/ or mud are subsequently transferred to the top drive unit 230 via a mud hose connection 238. Here, a mud hose connection 283 is shown, transferring mud from the mud hose 280 supported by the mud hose connector 281 on the support frame 245 to the conventional mud connector 282 on the top drive unit 230. Hence, the weight of the mud hose (etc.) is no longer supported by the top drive unit, but by the support frame 245.

[0113] This mud hose connection 283 can be disconnected from the top drive unit 230 upon removal of the top drive unit 230, while mud hose 280 remains connected to support frame 245. This is advantageous e.g. during maintenance of the top drive unit, or when an alternative top drive unit is to be installed, or when the trolley and elevator are used for purposes not requiring a top drive unit.

[0114] In FIGS. 8a-f an embodiment of a pipe positioning motion arm 60 supported by the trolley, in particular by support frame 45, is shown in in various positions. Such a pipe positioning motion arm 60 is provided to allow a pipe of the drill string to pass in a vertical orientation through the pipe passage of the rotating headclamp, and to position the shoulder of the pipe to allow engagement of the pipe of the drill string below a shoulder by the mobile pipe retainers in the operative position thereof.

[0115] It is likewise conceivable that such a pipe positioning motion arm is supported by the drilling tower, i.e as a motion arm assembly 2 as disclosed in WO2014/182160 and as visible in FIG. 1.

[0116] In FIG. 8a, an embodiment of a the pipe positioning motion arm 60 is shown per se. The pipe positioning motion arm 60 comprises an inner boom 61, pivotally attached about a horizontal first pivot axis 62 to the support frame 45, which inner boom is pivotable in a first rotation direction R1 from an upwardly angled parking position, as visible in FIG. 8a, to a substantially vertical downwardly angled position, as visible in FIG. 8e.

[0117] An outer boom 63 has one end which is pivotally attached to the inner boom 61 about a horizontal second pivot axis 64, parallel to and spaced from the first pivot axis 62. The outer boom 63 is pivotable in a second rotation direction, R2, opposite to the first rotation direction R1, between a parking position in which the outer boom and inner boom are essentially parallel, as visible in FIG. 8a, and a position in which the inner boom 61 and outer boom 63 extend essentially in line with each other, as visible in FIG. 8d. It is noted that essentially in line is to be interpreted as including an angle of >90. Further, a pipe gripper 65 is provided which is adapted to grip a pipe, which pipe gripper 65 is pivotally attached to an opposed end of the outer boom 63 opposite the end attached to the inner boom 61 about a horizontal pipe gripper pivot axis 66, parallel to the first pivot axis 62 and the second pivot axis 64, in in a pipe gripper rotation direction R3 corresponding to the first rotation direction R1.

[0118] A first pivot drive, here a hydraulic cylinder 71, is mounted between said support frame 45 and said inner boom 61 and adapted to pivot the inner boom 61. A second pivot drive, here embodied as parallel hydraulic cylinders 72, is mounted between said support frame 45 and said outer boom 63, and adapted to pivot the outer boom 63. A pipe gripper drive, here embodied as two parallel hydraulic cylinders 73, is mounted between said outer boom 63 and said pipe gripper 65 and adapted to pivot the pipe gripper. The first pivot drive 71, second pivot drive 72 and pipe gripper drive 73 are adapted to operate simultaneously.

[0119] Here, inner boom 61 is provided with an end stopper 68 against which the outer boom 63 is adapted to rest in the parking position, as visible in FIG. 8a.

[0120] In FIG. 8b, the pipe positioning motion arm 60 has been actuated, allowing the gripper 65 to engage on a lift sub 81, in particular below a shoulder 81b of the lift sub, attached to a pipe 80 of a drill string, in a non-vertical orientation, in particular a horizontal orientation, e.g. from a catwalk device.

[0121] Lift sub 81 is a pipe portion specially designed to be added to the drill string for lifting purposes. The lift sub is embodied with at least one shoulder. Here, the lift sub is embodied as a two-shouldered lift sub, comprising an upper shoulder 81 adapted to be engaged by the pipe retainers of a rotating headclamp, and a lower shoulder 81b adapted to be engaged by the gripper 65 of the pipe positioning motion arm 60. Not visible is that the two-shouldered lift sub further comprises a pin which is engaged in a box 80a of drill pipe 80.

[0122] An advantage of the shown pipe positioning motion arm 60 is that the vertical positioning of the lift sub 80, as visible in FIG. 8d, is carried out by a single drive, here the second pivot drive embodied as parallel hydraulic cylinders 72.

[0123] In FIGS. 9 and 10 a trolley and top drive unit of an alternative embodiment of a top drive well drilling installation according to the invention is shown. It is envisaged that the depicted installation is part of an offshore drilling vessel for performing offshore drilling and/or other wellbore related activities, e.g. well intervention. It will be appreciated that, when desired, the invention is also applicable to land based drilling installations.

[0124] The top drive well drilling installation comprises a drilling tower, not shown, which is e.g. embodied as a mast with a closed contoured steel structure with at least one firing line 5 outside of the mast itself. For example the mast is arranged adjacent a moonpool of a drilling vessel, or over a larger moonpool with two firing lines along opposed outer faces of the mast as is known in the art.

[0125] In an alternative design the drilling tower is embodied as a derrick with the firing line within the structure of derrick, e.g. the derrick having a lattice structure placed over the moonpool.

[0126] The mast, not shown per se, is provided at the side of the drill floor and is provided with two parallel vertical trolley rails 111a, 111b. A trolley 112 is guided along said trolley rails 111a, 111b.

[0127] A top drive unit 130 is attached to the trolley 112.

[0128] The top drive unit 130 comprises in this example four electric top drive motors 132a, 132b, 132c, 132d which commonly drive, via gearbox or transmission housing 135, a rotary stem or quill 131. As known in the art the quill 131 is connectable, e.g. via a threaded connection, e.g. via a saver sub, to the top end of a drilling tubular aligned with the firing line. Thereby the top drive unit 130 is able to impart rotary motion and drive torque to a drilling tubulars string.

[0129] A main hoisting device 120 is provided that is adapted to move the trolley with the top drive unit up and down along the vertical trolley rails 111a, 111b. For example the trolley and hoisting device have sufficient strength and capacity to handle a load of 1000 tons or more in the firing line.

[0130] The trolley 112 is provided with a rigid support frame 145 supporting the top drive unit 130, at least so as to absorb reaction torque from the motor of the top drive unit.

[0131] The rigid frame structure 45 with upper and lower trolley beams 145a, 145b that each have at each end thereof rollers engaging the respective trolley rail 111a, 111b on the mast. These beams 145a, 145b here have about a V-shape in top view. These beams 145a, 145b support here a single vertical rear frame member 145c, that embodies sort of a spine of the trolley 112 and that spans the height between the beams 111a, 111b.

[0132] This rear frame member 145c is provided with one or more, here a pair of parallel, vertical guide rails 160a, b. The top drive unit 130 is provided with a chassis 130a with rollers 130b or other guide members that cooperate with said guide rails 160a, b.

[0133] This rear frame member 145c may be embodied as a box girder.

[0134] From the top end of said rear frame member 145c a forward cantilevered frame member 145d extends, away from the mast. At its forward end this frame member 145d carries a transverse horizontal top frame member 145e, generally in a transverse imaginary plane that encompasses the firing line (not shown).

[0135] The top frame member 145e is provided with connectors, here holes, for connecting thereto a series of cable sheaves 121 in a side by side arrangement. The hoisting device 120, as a crown block, is also provided with cable sheaves so that the trolley 112 is suspended by one or more winch driven cables in a multiple fall arrangement.

[0136] The support frame 145 further comprises left and right frame members 145x, 145y which are suspended from the transverse horizontal top frame member in a transverse plane that encompasses the firing line. As depicted these left and right members 145x, 145y are directly and pivotally connected to the frame member 145e, here pivotal about an axis perpendicular to said transverse plane. As is preferred each left and right member 145x, 145y has an upper eye, as here through two spaced apart tabs, with a pin being secured through said eye and through a hole in the frame member 145e.

[0137] A rotatable head clamp assembly carrier 161 is connected, as is preferred releasably, with hooks 161b to lower ends of said left and right members 145x, 145y. The carrier 161 supports, here is integrated with, a rotatable head clamp assembly 162 of which an example is depicted in FIGS. 5, 6a-c. For example the rotatable head clamp assembly 162 is designed to handle a firing line load of at least 1000 tons.

[0138] As discussed the vertical guide rails 160a, 160b guide the top drive unit 130 as the rollers 130a, 130b of the chassis 130a ride along said rails 160a, b.

[0139] In this embodiment, as preferred, the same guide rails 160a,b also guide the carrier 161, here a guidance portion 161a thereof. Also, as preferred, the same guide rails 160a, b guide a wrench and/or clamping device 190, which will be discussed later.

[0140] In addition to guiding said components, the one or more guide rails 160a, b here, as is preferred, also serve the purpose of absorbing any reaction torque that is caused by operation of the installation on the respective component and transmit said torque to the frame 145.

[0141] Between the top drive unit 130 and the trolley frame 145 there are one or more vertical displacement actuators 140 so that the top drive unit 130 is vertically mobile relative to the frame by said one or more vertical displacement actuators, here adapted to perform controlled lowering and raising of the top drive unit during make up or breaking of the threaded connection between the quill or rotary stem on the one hand and the tool joint or box member of the tubular suspended from the rotatable head clamp assembly on the other hand.

[0142] The trolley is provided with an auxiliary hoisting device 180 that is adapted to vertically move at least the top drive unit 130, here also the device 190, relative to the frame. It is depicted that the device 180 includes a chain hoist device, with a hook that can be coupled to either the top drive chassis 130a or the device 190 as shown in FIG. 10.

[0143] Reference numeral 190 indicates a wrench and/or clamp device that allows to retain the tool joint or box member held by the assembly 162 when make-up or break-up of a threaded connection is performed.

[0144] In FIGS. 11a-11c an alternative embodiment of a pipe positioning device 260 is shown in various positions allowing the passage of a pipe of the drill string through the pipe passage of the rotating headclamp, shown in relation to the embodiment of FIGS. 9 and 10.

[0145] The pipe positioning device 260 is supported by the hooks 161b of the carrier 161, which are connected to lower ends of said left and right members 145x, 145y. The carrier 161 supports, here is integrated with, a rotatable head clamp assembly 162.

[0146] The pipe positioning device 260 is provided to allow a pipe 270 of the drill string to pass in a vertical orientation through the pipe passage of the rotating headclamp, and to position the shoulder of the pipe to allow engagement of the pipe of the drill string below a shoulder by the mobile pipe retainers in the operative position thereof.

[0147] Here, a lift sub 271 is attached to pipe 270 of the drill string. Lift sub 271 is a pipe portion specially designed to be added to the drill string for lifting purposes. The lift sub is embodied with at least one shoulder. Here, the lift sub is embodied as a two-shouldered lift sub, comprising an upper shoulder 271a adapted to be engaged by the pipe retainers of a rotating headclamp, and a lower shoulder 271b adapted to be engaged by a gripper of the pipe positioning device.

[0148] In FIG. 11a, it is visible that the pipe positioning device 260 of the shown embodiment comprises a pipe gripper 262 mounted pivotably about horizontal pivot axis 263 to support arms 261a, 261b. These support arms 261a, 261b are supported from transverse horizontal top frame member 145e via cylinders 262a, 262b respectively, allowing a vertical motion of the pipe gripper 252 relative to the carrier 161 of the rotating headclamp 162.

[0149] In FIG. 11a, the gripper 262 has engaged lift sub 271, in particular below shoulder 271b of the lift sub, in a non-vertical orientation, in particular a horizontal orientation, e.g. from a catwalk device.

[0150] In FIG. 11b, gripper 262 has rotated about pivot axis 263 to bring the pipe 270 with lift sub 271 to the vertical orientation, such that the pipe with lift sub is positioned in line with and below the rotating headclamp 162.

[0151] In FIG. 11c, cylinders 262a and 262b have been actuated to establish a vertical movement of the gripper 262 with the pipe and lift sub. As such, the pipe with lift sub is stabbed into the rotating headclamp, allowing with the pipe retainers in the non-operative position passage of the lift sub 271 through the pipe passage. By subsequently positioning the pipe retainers in the operative position the retainers engage below the shoulder 271a of the lift sub 271 of the pipe of the drill string extending through the pipe passage so as to suspend said drill string therefrom.