Wellbore drilling system

Abstract

A wellbore drilling system includes a drilling tower and a drill floor; a drilling tubulars storage rack adapted to store multiple drilling tubulars; a tubular racking device mounted on the drilling tower having first and second tubular racking assemblies; and a well center tools storage structure. The motion arm of the a first tubular racker assembly is provided with a connector, and well center tools and a tubular gripper member are provided with complementary connectors. The well center tools storage structure is arranged such that the well center tools stored therein are within reach of the first tubular racker assembly so as to allow connection of a well center tool to the motion arm while the well center tool is stored in the well center tools storage structure. With the at least one well center tool connected to the motion arm of the lower tubular racker assembly, the well center tool is operable above the drill floor.

Claims

1. A wellbore drilling system comprising: a drilling tower and a drill floor having a well center through which a drill string passes along a firing line; a drilling tubulars storage rack adapted to store multiple drilling tubulars in a vertical orientation; a tubular racking device mounted on the drilling tower having at least a lower first tubular racker assembly and at least a second tubular racker assembly operable at a greater height than the first tubular racker assembly, each of the first and second tubular racker assemblies comprising a base, a motion arm connected to said base, and a tubular gripper member connected or connectable to the motion arm, wherein the tubular racking device has a reach at least allowing to transfer a tubular gripped by said first and second tubular racker assemblies between the drilling tubulars storage rack and a position of the tubular aligned with the firing line above the well center, so as to allow for building and disassembly of a tubulars string, and wherein, with the tubular gripping members connected to the motion arms of the racker assemblies, the tubular racking device is adapted to grip and retain a drilling tubular by the tubular racker assemblies and to place a tubular in and remove a tubular from the drilling tubulars storage rack; one or more well center tools, each of the one or more well center tools being adapted for operation above the well center of the drill floor; and a well center tools storage structure adapted to store therein the one or more well center tools, wherein the motion arm of the lower first tubular racker assembly is provided with a connector, and the one or more well center tools and the tubular gripper member are provided with complementary connectors, wherein said well center tools storage structure is arranged such that said one or more well center tools stored therein are within reach of the first tubular racker assembly so as to allow connection of a well center tool to the motion arm while the well center tool is stored in the well center tools storage structure, and wherein, with the at least one well center tool connected to the motion arm of the lower tubular racker assembly, the well center tool is operable above the drill floor.

2. The wellbore drilling system according to claim 1, wherein said multiple drilling tubulars are multi-jointed tubulars.

3. The wellbore drilling system according to claim 1, wherein the well center tools storage structure is provided at a bottom part of the drilling tubulars storage rack.

4. The wellbore drilling system according to claim 1, wherein the well center tools storage structure comprises multiple levels above one another to store well center tools therein at multiple levels above one another.

5. The wellbore drilling system according to claim 1, wherein one or more of the following well center tools can be stored in the well center tools storage: an iron roughneck for making up and breaking out of threaded tubular joint; a raised back-up system clamp adapted to clamp a drill string top end at an elevated position above the drill floor; a guide sheave for one or more lines to be introduced into the well bore; a thread doper adapted to clean a threaded tubular end and to dope the threaded tubular end; a mud bucket adapted to catch mud upon tripping in order to retrieve mud allowing for re-use of the mud; any type of end effector; a man basket; a bolting tool; a multibolt torque tool; a centralizer tool for guiding risers; a guide for drill pipes; and a winch and hook.

6. The wellbore drilling system according to claim 1, wherein an iron roughneck storage is provided at an elevated position within the construction of the drilling tower.

7. The wellbore drilling system according to claim 1, wherein a first and a second drilling tubulars storage rack is provided on opposite sides of the drilling tower, and wherein a first tubular racking device is arranged to transfer tubulars between the first drilling tubulars storage rack and the firing line, and wherein a second tubular racking device is arranged to transfer tubulars between the second drilling tubulars storage rack and the firing line.

8. The wellbore drilling system according to claim 1, wherein two well center tool storage structures are provided.

9. The wellbore drilling system according to claim 1, wherein two well center tool storage structures are provided, and wherein a first well center tool storage structure is arranged such that said one or more well center tools stored therein are within reach of a first tubular racking device, and a second well center storage tool storage structure is arranged such that said one or more well center tools stored therein are within reach of a second tubular racking device.

10. The wellbore drilling system according to claim 9, wherein a first iron roughneck device is stored in the first well center tool storage structure, and a second iron roughneck device is stored in the second well center tool storage structure.

11. The wellbore drilling system according to claim 10, wherein the second iron roughneck device is set to handle different diameter tubulars than the tubulars handled by the first iron roughneck.

Description

(1) The invention will now be explained in more detail with reference to the appended drawing. In the drawing:

(2) FIG. 1 shows a plan view of a drilling vessel with a system according to the invention,

(3) FIG. 2 shows on a larger scale a part of FIG. 1,

(4) FIG. 3 shows a perspective side view of a part of a drilling vessel with a system according to the invention,

(5) FIG. 4 shows a side view of a part of a drilling vessel with a system according to the invention,

(6) FIG. 5 shows a front view of a part of a drilling vessel with a system according to the invention,

(7) FIG. 6 shows a perspective view of a part of a drilling vessel with a system according to the invention,

(8) FIG. 7 shows a racker assembly of the system of FIG. 6,

(9) FIG. 8 shows the racker assembly of FIG. 7 in side view, partly as wire frame,

(10) FIG. 9 shows the racker assembly of FIG. 7 in top view,

(11) FIG. 10 illustrates the handling of a tubular by means of the racker assemblies with the lower assembly supporting an iron roughneck device,

(12) FIG. 11 shows in plan view a portion of the vessel of FIG. 6,

(13) FIG. 12 shows a top view of a fingerboard disc according to the second aspect of the invention,

(14) FIGS. 13a, b show a fingerboard disc member adapted for drill pipe and a fingerboard disc member adapted for casing respectively, without latch devices thereon,

(15) FIGS. 14a, b show the disc members of FIGS. 13a, b provided with latch devices thereon,

(16) FIG. 15 shows the part of a drilling vessel of FIG. 6, with an alternative drilling tubulars storage rack,

(17) FIG. 16 shows a top view of a fingerboard disc of FIG. 12 including a tool storage.

(18) With reference to the FIGS. 1-5 now an embodiment of an oil and gas offshore drilling vessel equipped with a wellbore drilling system according to the invention will be explained.

(19) The vessel 1 here is a monohull vessel having a hull 2 with a moonpool 3 extending through the hull. A drilling tower, here mast 4 is mounted on the hull, here above the moonpool 3. The mast is associated with hoisting means, in the art called drawworks, in the shown embodiment forming two firing lines 5, 6 along and on the outside of the mast, here fore and aft of the mast 4, that extend through the moonpool 3.

(20) A drill floor 25 is provided, having a well center 27 through which a drill string passes, along the firing line, here firing line 5.

(21) The firing line 5 is designed for performing drilling, and here includes a drill string rotary drive, here a top drive 7 or other rotary drive, adapted for rotary driving a drill string.

(22) The vessel 1 is equipped with two drilling tubulars rotary storage racks 10, 11 adapted to store multiple drilling tubulars 15 in vertical orientation, preferably multi-jointed tubular. As can be seen in FIGS. 1 and 2 the vessel has a longitudinal central axis 300, and the drilling tubulars rotary storage racks 10, 11 are arranged symmetrical with respect to said longitudinal central axis 300, on opposite sides of the drilling mast 4.

(23) Preferably, as visible in FIG. 5, each drilling tubulars rotary storage rack is rotatable mounted on the vessel so as to rotate about a vertical axis. In particular, drilling tubulars rotary storage rack 10 is rotatable about rotation axis 30. A lower bearing 12 is visible at the lower end of the rack, connecting the rack 10 to the hull 2. Also, as is preferred, an upper bearing 32 is present at the top end of the rack, connecting said top end to a support frame 33. Here the support frame connects the top end of the rotary rack to the mast 4.

(24) As is known in the art each drilling tubulars rotary storage rack 10, 11 includes slots for the storage of multiple tubulars in each drilling tubulars rotary storage rack in vertical orientation. As is known in the art the racks 10, 11 here include a central vertical post 10a, 11a, and multiple disc members 15a, 15b, 15c at different heights of the post, at least one disc being a fingerboard disc having tubulars storage slots, each slot having an opening at an outer circumference of the fingerboard disc allowing to introduce and remove a tubular from the storage slot. It is envisaged that in a preferred embodiment the tubulars rest with their lower end on a lowermost disc member 15d. In the example shown in the FIGS. 1-5 it is envisaged that triple stands are stored in the racks 10, 11. The diameter of each rack 10, 11 is about 8 meters.

(25) Also schematically indicated are drive motors 18, 19 for each of the first and second drilling tubulars rotary storage rack 10, 11 that allow to rotate the drilling tubulars storage rack about its vertical axis. In a possible embodiment the drive motors 18, 19 are embodied as part of an indexing drive for the racks, so that each of the rack can be brought in a multitude of predetermined rotary positions.

(26) The vessel 1 also includes a horizontal catwalk machine 80 on the deck and aligned with the relevant firing line and allowing to bring tubulars from a remote position towards the firing line or to a stand-building location, e.g. from hold for horizontal storage of drilling tubulars in the aft portion of the hull and/or the deck storage. A crane 17 is provided to place tubulars on the catwalk machine 80 and remove them there from. As is preferred the catwalk machine 80 is arranged on the central longitudinal axis 300 of the vessel on the deck. The vessel 1 also includes a driller's cabin 85.

(27) In the shown embodiment, four tubular racking devices 40, 40, 40, 40 are provided, at all four corners of the mast 4, two adjacent each firing line 5, 6, and two adjacent each drilling tubulars rotary storage rack 10, 11: tubular racking device 40 is arranged to transfer tubulars between the first drilling tubulars storage rack 10 and firing line 5, tubular racking device 40 is arranged to transfer tubulars between the first drilling tubulars storage rack 10 and firing line 6, tubular racking device 40 is arranged to transfer tubulars between the second drilling tubulars storage rack 11 and firing line 5, tubular racking device 40 is arranged to transfer tubulars between the second drilling tubulars storage rack 11 and firing line 6,

(28) A tubular racking device according to the invention, as in particular tubular racking device 40 as visible in FIG. 4, comprises a lower first tubular racker assembly 41, a second tubular racker assembly 42, operable at a greater height than the first tubular racker assembly, and a third tubular racker assembly 43. Although only explained in relation to tubular racker assemblies 42, 43 each tubular racker assembly comprises comprising a base 42b, 43b, a motion arm 42m, 43m connected to said base 42b, 43b; and a tubular gripper member 42t, 43t connected or connectable to the motion arm 42m, 43m and adapted to grip a tubular.

(29) The base of the first tubular racker assembly 41 is vertically mobile between a lower operative position wherein the corresponding gripper member can place a tubular in and remove a tubular from the drilling tubulars storage rack and a raised position. The base of the third tubular racker assembly 43 is also vertically mobile, at least between a well center servicing position, that is below the lower operative position of the base of the first tubular racker assembly, and said lower operative position of the base of the first tubular racker assembly if said first tubular racker assembly is moved to a raised position. With the base of the third tubular racker assembly 43 in said lower operative position of the base of the first tubular racker assembly 41, and with a tubular gripper member connected to the motion arm, the third tubular racker assembly 43 is operable for tubular transfer between the firing line 5 and the drilling tubulars storage rack 10, in combination with the second tubular racker assembly 42, e.g. in case of failure of the first tubular racker assembly 41.

(30) To provide the vertical mobility, the bases 41b, 43b are guided along a vertical rails 44. Optionally, as visible in the top view of FIGS. 1 and 2, the tubular racking devices includes a vertical column member 45, 45, 45, 45 provided with said one or more rails, said column member 45, 45, 45, 45 supporting said tubular racker assemblies.

(31) Each tubular racking device 40, 40, 40, 40 is adapted to grip and retain a drilling tubular by the tubular racker assemblies, wherein the weight of the tubulars is distributed over the motion arms of the tubular racker assemblies, and wherein the tubular racking device is adapted to place a tubular in and remove a tubular from the drilling tubulars storage rack,

(32) Each tubular racking device 40, 40, 40, 40 has a reach at least allowing to transfer a tubular gripped by said first and second tubular racker assemblies between the drilling tubulars storage rack 10, 11 and a position of the tubular aligned with the firing line 5, 6 above the well center so as to allow for building and disassembly of a tubulars string, e.g. a drill string or a casing string.

(33) The system further comprises one or more well center tools 51, 52, 53, each adapted for operation above the well center 27 of the drill floor 25. Optional well center tools are: an iron roughneck for making up and breaking out of threaded tubular joint, a raised back-up system clamp adapted to clamp a drill string top end at an elevated position above the drill floor, a guide sheave for one or more lines to be introduced into the well bore, a thread doper adapted to clean a threaded tubular end and to dope the threaded tubular end, a mud bucket adapted to catch mud upon tripping in order to retrieve mud allowing for re-use of the mud.

(34) In the shown embodiment, each well center tool 51, 52, 53 is adapted to be gripped by the tubular gripper member 43t connected to the motion arm 43m.

(35) According to a first aspect of the present invention,with the base 43b of the third tubular racker assembly 43 in the well center servicing position and a well center tool 51, 52 or 53 connected to the motion arm 43m thereofthe well center tool 51, 52 or 53 is operable above the drill floor 25, whilst the first and second tubular racker assemblies 41, 42 are operable in combination for tubular transfer between the firing line 5 and the drilling tubulars storage rack 10. Preferably, the well center tools have identical mechanical connectors that are connectable to the motion arm 43m.

(36) According to a possible embodiment of the invention, a well center tools storage structure 55 is provided that is adapted to store therein the one or more well center tools 51, 52, 53, 54a, 54b that are connectable to the motion arm 43m of the third tubular racker assembly 43. As is preferred and visible in FIG. 4, the well center tools storage structure 55 is adapted to store well center tools 51, 52, 53 therein at least at multiple levels above one another. It is also possible to store well center tools 54a, 54b adjacent each other as visible in top view in FIGS. 1 and 2.

(37) Said well center tools storage structure 55 is arranged such that said one or more well center tools 51, 52, 53, 54a, 54b stored therein are within reach of the third tubular racker assembly 43 so as to allow connection of a well center tool to the motion arm 43m while the well center tool is stored in the well center tools storage structure 55.

(38) With reference to FIGS. 6-11 now another embodiment of a well drilling system according to the invention will be described.

(39) In FIG. 6 the mast 4 (shown in FIG. 6 with the top section including the drawworks and topdrive removed), the drill floor 25, and the well center 27 are shown.

(40) Also shown are the storage racks 10, 11 for tubulars, e.g. drill pipes and casing, here multi-jointed tubulars.

(41) At the side of the mast 4 facing the drill floor 25 two tubular racking devices 140 and 140 are mounted, each at a corner of the mast 4. If no mast is present, e.g. with a latticed derrick, a support structure can be provided to arrive at a similar arrangement of the racking devices 140 and 140 relative to the drill floor 25 and well center 27.

(42) As is preferred each racking device 140, 140 has multiple, here three racker assemblies. Here a lower first tubular racker assembly 141, 141, a second tubular racker assembly 142, 142, operable at a greater height than the first tubular racker assembly, and a third tubular racker assembly 143, 143.

(43) Each set of racker assemblies is arranged on a common vertical rails 145, 145 that is fixed to the mast 4, here each at a corner thereof.

(44) In FIG. 6, as can be better seen in the depiction of FIG. 10, a drill pipe multi-joint tubular 15 is held by racker assemblies 142 and 141 in the firing line above the well center 27, thereby allowing to connect the tubular 15 to the drill string supported, e.g., by a non-depicted drill sting slip device in or on the drill floor 25. Each of said assemblies 142 and 141 carries a tubular gripper member 142t and 141t at the end of the motion arm of the assembly.

(45) The lower racker assembly 143 of the other racker device 140 carries an iron roughneck device 150, here with a spinner 151 thereon as well.

(46) As can be seen in FIGS. 7-9 the motion arm 141m is here embodied a telescopic extensible arm, the arm having a first arm segment 141m-1 which is connected to the base 141b via a vertical axis bearing 147 allowing the motion arm 141m to revolve about this vertical axis. As is preferred this vertical axis forms the only axis of revolution of the motion arm. The motion arm has two telescoping additional arm segments 141m-2 and 141m-3, with the outer arm segment being provided with a connector 148 for a tubular gripper 141t and/or a well center tool (e.g. iron roughneck device 150).

(47) Advantageously, the telescopic extensible arm is retractable in a direction opposed to the direction of extension. As the telescopic extensible arm of this embodiment extends beyond the vertical axis bearing 147 in the direction opposed to the direction of extension, a very compact retracted position can be achieved as indicated by dashed line R in FIG. 11. The position of gripper 141t below the motion arm 141m further attributes to the compact retracted position.

(48) As visible in FIG. 8, in the example shown a hydraulic cylinder 152 is present between first and second segments of the arm, and a further cylinder 153 between the second and third segments of the arm. Each cylinder 152, 153 is operable to cause extension and retraction of the arm. For example the racker assembly is provided with a self-contained hydraulic unit 154 including an electric motor driven pump, a tank, and valves.

(49) In FIGS. 6, 9 and 10 it can be recognized that each tubular racking device comprises a vertical guide rail 145 onto which corresponding guide members of the base 141b of each tubular racker assembly engage. In this example the base 141b carrier four sets of each three rollers 149 of which two rollers 149 ride along opposed faces of a flange of the rails 145 and one roller rides along a lateral side of the flange.

(50) The tubular racker device further comprises a vertical toothed rack 160 arranged parallel to this vertical guide rails 145. Here the toothed rack 160 is mounted on the rail 145, here on a front plate of the rail between the two flanges of the rail 145.

(51) The base 141b of the tubular racker assembly 141 is provided with one or more, here two, pinions 161 engaging with this vertical toothed rack 160. The base is provided with one or more motors 162, here two, driving the pinions, so as to allow for a controlled vertical motion of the racker assembly 141.

(52) As is preferred the one or more motors 162 driving the one or more pinions 161 are electric motors. In an embodiment a supercapacitor is included in an electric power circuit feeding said one or more vertical motion motors, which allows the temporary storage of electricity that may be generated by said one or more motors during a downward motion of the assembly. This energy can then be used for the upward motion again.

(53) In view of a reduction of the number of parts it is preferred for all motion arms to be identical, so that limited spare parts are needed. For example a single complete motion arm, or a single complete racker assembly is stored aboard the vessel.

(54) In view of reduction of the number of parts it is preferred for the vertical axis bearing 147 between the base 141b and the motion arm 141m to be arranged in a bearing housing 147a that is releasable attached to the base 141b of the racker assembly. As depicted here the base 141b provides both a left-hand attachment position L, as indicated in FIG. 7, and a right-hand attachment position, as shown in use in FIG. 7, for the bearing housing 147a which allows to use the same base in each of the racking devices 140 and 140. As is preferred the attachment positions are formed by elements on the base having holes therein and the housing 147a having mating holes therein, so that one or more connector pins 156 can be used to secure the housing to the base.

(55) As shown in FIG. 10 the motion arm assembly 143 holds iron roughneck device 150 above the well center for make-up or breaking up of connections between tubulars in the firing line 5. At the same time the other motion arm assembly 143 can be equipped with a second iron roughneck device, which is then already prepared for handling different diameter tubulars.

(56) As explained, should e.g. assembly 141 fail to operate, it task can be taken over by assembly 143 on the same rails 145 as it may be quickly equipped with a tubulars gripper and brought to the level appropriate for tubulars racking. For example the assembly 141 is then raised to make room for the assembly 143.

(57) In FIG. 11 a fingerboard disc member 15a of rack 11 is shown. As can be seen the rack 11 is arranged along a lateral side of the mast 4, with the drill floor 25 with firing line 5 forward of the mast 4 and with a riser handling side rearward of the mast 4.

(58) As can be seen it is, in embodiments, envisaged that one or more racker devices and/or assemblies thereof as described in this application are present at said riser handling side, here assembly 141opposite the drilling side (where assembly 141 is provided)of the mast 4. For example a riser gripper tool may be arranged in storage structure 55 to be mechanically interconnected to the motion arm of assembly 141 in the manner as described herein. Another tool that may be of use at the riser handling side of the mast is e.g. a bolting tool to tighten or release bolts interconnecting riser sections. As is preferred a further vertical rails 145 is present at said riser handling side as well.

(59) The fingerboard disc 15a is embodied according to a second aspect of the invention is shown, which is provided around a central vertical post 11a. The fingerboard disc 15a comprises multiple tubulars storage slots, each slot having an opening at an outer circumference of the fingerboard disc allowing to introduce and remove a tubular from the storage slot.

(60) As will be explained now in more detail with reference to FIGS. 12, 13, and 14, the fingerboard disc 15a is composed of multiple fingerboard disc members, here ten fingerboard disc members 115a-115j.

(61) As in a preferred embodiment of the second aspect of the invention, some disc members 115a-e have slots of a first width, here to accommodate casing pipes, and some disc members 115f-j have slots of a second different width, here to accommodate drill pipes. As can be seen it is envisaged that adjacent disc members may form a further slot at their interfacing sides.

(62) As is preferred disc members provided with different width slots are identical as to their inner connection portion that is adapted to be connected to the central post 11a and as to their sides that adjoin the neighboring disc members, so as to allow for any combination of disc members in the disc 15a, thereby allowing to optimize the storage capacity of the rack 11 in view of the operation performed with the vessel. For example each disc member has sides diverging at a 36 degree angle so that ten disc members make up an entire disc. Of course it will also be possible to divide the disc 15a in a different number of disc members, e.g. eight or twelve disc members.

(63) As is preferred all disc members have an identical connector portion adapted to connect the disc member to the central post 11a. As is preferred each disc member has at its inner end a series of holes 116 through which bolts or pins can be fitted to secure the disc to the central post 11a.

(64) In an embodiment a disc member 115a-f has three deep slots and between two deep slots a slot of reduced depth, e.g. the deep slots accommodating nine drill pipe stands and the reduced depth slot accommodating three drill pipe stands.

(65) In an embodiment a disc member 115g-i has two deep slots to accommodate casing pipe stands, e.g. four per slot.

(66) As shown in FIGS. 14a, b it is envisaged that a disc member 115a-f, 115g-i may be pre-fitted with a latch device having latch members that secure each tubular at a location of the slot, e.g. (as in this example), each latch member having a pivotal latch finger 117 that extends across the slot in a securing position and can be pivoted to a release position, e.g. by an associated actuator, e.g. a pneumatic or hydraulic cylinder.

(67) As explained here, it is envisaged that a disc member 115a-i can be gripped or otherwise engaged by a tubular racker assembly and moved along the height of the tower by means of said assembly, e.g. in the process of exchanging disc members to alter the storage capacity of the rack. For example a retainer can be slided into a slot of the disc, the retainer having a pipe stub that can be gripped by a tubular gripper so the disc is effectively held by the retainer and can be conveyed along the height of the tower.

(68) In FIG. 15 the part of a drilling vessel of FIG. 6 is shown, wherein the drilling tubulars storage rack 11 is at its bottom part provided with a tool storage structure 200. The rack is accordingly used for shorter tubulars than rack 10. Other configurations are also conceivable, e.g. wherein the tool storage structure is provided at a central part of the drilling tubulars storage rack 11, and short (single) tubulars are stored above and below the tool storage structure 200. Preferably at least two tubular racker assemblies of a tubular racking device can reach into the tool storage structure. An advantage of the tool storage structure in the drilling tubulars storage rack 11 is that tubular racking devices of both sides of the mast 4 can reach into the tool storage structure 200.

(69) In FIG. 16 a top view of an alternative fingerboard disc is shown, including tool storage compartments 201, in the shown embodiment two. It is conceivable that the entire segments are tool storage compartments, but it is also conceivable that an upper or bottom part of the segment is also adapted to store tubulars.