The present disclosure relates in general to drilling rigs, and in particular to drilling rigs employing top drives, tubular handling devices, pivoting drilling towers, or combinations thereof.
The present disclosure is best understood from the following detailed description when read with the accompanying figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.
It is to be understood that the following disclosure provides many different embodiments, or examples, for implementing different features of various embodiments. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. Moreover, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed interposing the first and second features, such that the first and second features may not be in direct contact.
Referring to
Referring to
Referring to
Referring to
Referring to
In operation, in an exemplary embodiment with continuing reference to
The electric motors 52a-52c cause the respective pinions operably coupled thereto, including the pinion 56, to rotate and engage teeth of the rack 36a. Likewise, the electric motors 54a-54c cause the respective pinions operably coupled thereto, including the pinion 58, to rotate and engage teeth of the rack 36b. As a result, the carriage 24 and thus the top drive 26 move along the axis 20 and relative to the tower 18 as necessary so that the top drive 26 is at a position along the axis 20 at which the tubular member 72 can be coupled to the top drive 26. Before, during or after the top drive 26 is at that position along the axis 20, the actuators 48a and 48b actuate, extending their respective lengths. As a result, the linking member 42 pivots about an axis 74 (shown in
As a result of the extension of the actuators 48a and 48b and thus the pivoting of each of the linking member 42 and the top drive 26, the top drive 26 moves between the position 28 and the position 30, which positions are shown in
After the tubular member 73 has vertically cleared the rig floor 14, the actuators 48a and 48b are actuated to their respective retracted positions. To be clear, the vertical clearance should be sufficient to provide clearance of the tubular member 73 even if it is lowered slightly as the top drive 26 returns to the position 28; alternatively, it is desired to have a corresponding upward movement of the top drive 26 along the axis 80 as the top drive 26 returns to the position 28 as further discussed below. As a result, the linking member 42 pivots about the axis 74. As viewed in
The electric motors 52a-52c and 54a-54c move the top drive 26 downward along the axis 20 and relative to the tower 80, lowering the tubular members 72 and 73 through an opening 84 formed in the platform 12. The opening 84 defines an axis 86, which is spaced in a parallel relation from the axis 20 by the spacing 82. The axis 86 is generally coaxial with the wellbore 16. Before, during or after the lowering of the tubular members 72 and 73, the top drive 26 operates to couple the tubular member 73 to another tubular member either extending in the wellbore 16 or being vertically positioned between the wellbore 16 and the tubular member 73; this other tubular member may be part of a string of drill pipe or casing. In several exemplary embodiments, during or after the lowering of the tubular members 72 and 73, the top drive 26 is positioned at the position 28 shown in
In an exemplary embodiment, the motors 52c and 54c may be omitted from the apparatus 10. In an exemplary embodiment, the motors 52b, 52c, 54b and 54c may be omitted from the apparatus 10. In an exemplary embodiment, in addition to the motors 52a-52c and 54a-54c, one or more additional electric motors may be coupled to the carriage 24 and employed to move the top drive 26.
Referring to
Electric motors 104 and 106 are coupled to the carriage 98 and thus to the top drive 100. The electric motors 104 and 106 are spaced from each other in a direction that is parallel to the axis 97. In an exemplary embodiment, each of the electric motors 104 and 106 is an AC motor and is controlled by either a single variable-frequency drive (VFD) or multiple VFDs, which is/are synchronized and programmed to work simultaneously with the other motors to provide uniform motion and torque. In an exemplary embodiment, one or more of the electric motors 104 and 106 are controlled by a single VFD. In an exemplary embodiment, one or more the electric motors 104 and 106 are controlled by multiple VFDs. In an exemplary embodiment, each of the electric motors 104 and 106 is an AC motor and provides primary dynamic braking. In an exemplary embodiment, each of the electric motors 104 and 106 includes a gearbox and a brake therein or thereat. In an exemplary embodiment, each of the electric motors 104 and 106 includes an encoder incorporated on the motor shaft to provide more precise VFD control. A telescoping support member 108 extends between the base 90 and the portion 92a of the tower 92.
Referring to
Referring to
In operation, with continuing reference to
In an exemplary embodiment, during operation, the electric motor 106 causes the pinion 126 to rotate and engage the teeth of the rack 112b. Likewise, the electric motor 104 causes the pinion operably coupled thereto (which is identical to the pinion 126) to rotate and engage the teeth of the rack 112a. As a result, the carriage 98 and thus the top drive 100 move up or down, along the axis 97 and relative to the tower 92 as necessary or desired.
In several exemplary embodiments, during operation, before, during or after the top drive 100 is at a necessary or desired position along the axis 97, the actuators 122a and 122b may actuate, extending their respective lengths. As a result, the linking member 114 pivots at the pivot connection 116. As viewed in
In several exemplary embodiments, during operation, after the linking member 114 has pivoted to a pivot position corresponding to the respective extended positions of the actuators 112a and 112b, the actuators 112a and 112b may be actuated to their respective retracted positions. As a result, the linking member 114 pivots in a counterclockwise direction, as viewed in
In operation, in an exemplary embodiment, the apparatus 88 is employed to assemble a string of tubular members, such as drill pipe or casing as part of oil and gas exploration and production operations, in a manner similar to the above-described manner in which the apparatus 10 is employed to assemble a string of tubular members. In several exemplary embodiments, during operation, after the apparatus 88 has been placed in the configuration shown in
Referring to
In operation, in an exemplary embodiment, the base 90 is positioned adjacent a rig substructure 132, which defines an axis 133. As shown in
Before the portion 92b is pivoted from the pivot position shown in
Before, during or after the portion 92b is pivoted from the pivot position shown in
As shown in
In an exemplary embodiment, during operation, the electric motor 106 causes the pinion 126 to rotate and engage the teeth of the rack 112b. Likewise, the electric motor 104 causes the pinion operably coupled thereto (which is identical to the pinion 126) to rotate and engage the teeth of the rack 112a. As a result, the carriage 98 and thus the top drive 100 move up or down, relative to the tower 92, as necessary or desired.
In several exemplary embodiments, during operation, before, during or after the top drive 100 is at a necessary or desired position relative to the tower 92, the actuator 138 may be actuated to its retracted position. As a result, the linking members 140 and 142 pivot about their respective pivot connections at the carriage 98, pivoting in a counterclockwise direction as viewed in
In operation, in an exemplary embodiment, the apparatus 131 is employed to assemble a string of tubular members, such as drill pipe or casing as part of oil and gas exploration and production operations, in a manner similar to the above-described manner in which the apparatus 10 is employed to assemble a string of tubular members. In several exemplary embodiments, during operation, after the apparatus 131 has been placed in the configuration shown in
Referring to
The apparatus 148 further includes a tubular handling device 150. The tubular handling device 150 includes a vertically-extending support member 152. An arm 154 is pivotally coupled to the vertically-extending support member 152. At its pivot coupling to the vertically-extending support member 152, the arm 154 defines an axis 156, which is parallel to the axis 20 and spaced therefrom in the direction 78. A gripper 158 is coupled to the distal end portion of the arm 154. An axis 160 is defined by the arm 154 at its coupling to the gripper 158. The axis 160 is perpendicular to the axis 156, regardless of the pivot position of the arm 154 with respect to the axis 156.
The arm 154 includes segments 154a, 154b and 154c. The segment 154a is pivotally coupled to the vertically-extending support member 152. The segment 154b is pivotally coupled to the segment 154a at a pivot connection 154d. The segment 154c is pivotally coupled to the segment 154b at a pivot connection 154e. The gripper 158 is coupled to the segment 154c at the axis 160. A support pedestal 162 of one or more supports is positioned proximate the platform 12.
The tubular handling device 150 further includes a vertically-extending support member 164, an arm 166, a gripper 168 and a support pedestal 170, which are identical to the vertically-extending member 152, the arm 154, the gripper 158 and the support pedestal 162, respectively. An axis 171 is defined by the arm 166 at its coupling to the gripper 168. The vertically-extending support member 164, the arm 166, the gripper 168 and the support pedestal 170 are arranged to be symmetric, about an axis 172, to the vertically-extending member 152, the arm 154, the gripper 158 and the support pedestal 162, respectively. The axis 172 is perpendicular to each of the axes 20 and 74, extends midway between the racks 36a and 36b, and intersects the axis 86. At its pivot coupling to the vertically-extending support member 164, the arm 166 defines an axis 173, which is parallel to the axis 20 and spaced therefrom in the direction 78. The axis 173 is parallel to the axis 156 and symmetric thereto about the axis 172. The axis 171 is perpendicular to the axis 173, regardless of the pivot position of the arm 166 with respect to the axis 173. The vertically-extending member 152, the arm 154, the gripper 158 and the support pedestal 162 will not be described in further detail.
The apparatus 148 further includes a plurality of tubular members 174 positioned proximate the support pedestal 162, and a plurality of tubular members 176 positioned proximate the support pedestal 170. Each tubular member in the pluralities of tubular members 174 and 176 is coupled to one other tubular member when joining tubulars. The coupled tubular members 72 and 73 are part of the plurality of tubular members 174.
In operation, in an exemplary embodiment with continuing reference to
As shown in
Before, during or after the movement of the gripper 158 in the direction 78, the gripper 158 rotates about the axis 160, relative to the arm 154, so that the gripper 158 extends horizontally, perpendicular to the vertically-extending support member 152. The gripper 158 engages the tubular member 73. In an exemplary embodiment, the gripper 158 engages the tubular member 73 by gripping the tubular member 73. The arm 154 then moves upward along the vertically-extending support member 152 and thus the axis 156, lifting the coupled tubular members 172 and 173 upward. During this lifting, as viewed in
After the coupled tubular members 72 and 73 extend vertically and have been lifted high enough to clear the rig floor 14, the arm 154 pivots about the axis 156, pivoting the coupled tubular members 72 and 73 in a counterclockwise direction as viewed in
In an exemplary embodiment, before, during or after the coupling of the top drive 26 to the tubular member 72 and the subsequent lowering of the tubular members 72 and 73, the arm 166 pivots about the axis 173 in a counterclockwise direction, as viewed in
After the coupled tubular members 180 and 182 extend vertically and have been lifted high enough to clear the rig floor 14, the arm 166 pivots about the axis 173, pivoting the coupled tubular members 180 and 182 in a clockwise direction as viewed in
In view of all of the above and the figures, one of ordinary skill in the art will readily recognize that the present disclosure introduces an apparatus including a base; and a drilling tower pivotally coupled to the base to pivot the drilling tower between first and second pivot positions, the drilling tower including a first portion; and a second portion pivotally coupled to the first portion to pivot the second portion between third and fourth pivot positions when the drilling tower is in the first pivot position. According to one aspect, the second portion pivots from the third pivot position to the fourth pivot position in a second pivot direction; and wherein the drilling tower pivots from the first pivot position to the second pivot position in a second pivot direction opposite the first pivot direction. According to another aspect, the apparatus includes a telescoping member extending between the base and the first portion. According to yet another aspect, the apparatus includes a top drive coupled to the drilling tower and movable along each of the first and second portions of the drilling tower when the second portion is in the fourth pivot position. According to still yet another aspect, the apparatus includes a carriage to which the top drive is coupled, wherein the carriage is movably coupled to the drilling tower; and a linking member that is coupled to each of the carriage and the top drive and that pivots between fifth and sixth pivot positions; wherein the top drive defines a first axis; wherein a first spacing is defined between the first axis and the first portion of the drilling tower when the linking member is in the fifth pivot position; wherein a second spacing is defined between the first axis and the first portion of the drilling tower when the linking member is in the sixth pivot position; and wherein the second spacing is greater than the first spacing. According to still yet another aspect, the apparatus includes a first electric motor coupled to the top drive and movable therewith to move the top drive along each of the first and second portions of the drilling tower when the second portion is in the fourth pivot position. According to still yet another aspect, the drilling tower includes a first rack; and wherein the apparatus further includes a first pinion operably coupled to the first electric motor and engaged with the first rack to move the top drive along each of the first and second portions of the drilling tower when the second portion is in the fourth pivot position. According to still yet another aspect, the drilling tower further includes a second rack spaced from the first rack in a parallel relation; and wherein the apparatus further includes a second electric motor coupled to the top drive and movable therewith to move the top drive along each of the first and second portions of the drilling tower when the second portion is in the fourth pivot position; and a second pinion operably coupled to the second electric motor and engaged with the second rack to move the top drive along each of the first and second portions of the drilling tower when the second portion is in the fourth pivot position. According to still yet another aspect, the apparatus includes a carriage to which each of the top drive and the first and second electric motors is coupled. According to still yet another aspect, the drilling tower extends longitudinally along a first axis; wherein the first and second electric motors are spaced from each other in a direction that is perpendicular to the first axis; and wherein the first and second pinions are spaced from each other in the direction. According to still yet another aspect, the drilling tower extends longitudinally along a first axis; wherein the first and second electric motors are spaced from each other in a first direction that is parallel to the first axis; wherein the first and second pinions are spaced from each other in the first direction and in a second direction that is perpendicular to the first axis; and wherein the apparatus further includes third and fourth pinions engaged with the first and second racks, respectively, wherein the third and fourth pinions are spaced from each other in each of the first and second directions. According to still yet another aspect, the apparatus includes the drilling tower extends longitudinally along a first axis; wherein the apparatus further includes a carriage coupled to the drilling tower; and a linking member pivotally coupled to the carriage to permit the linking member to pivot between fifth and sixth pivot positions about a second axis that is perpendicular to the first axis; and wherein the top drive extends longitudinally in a parallel relation to the drilling tower, and is pivotally coupled to the linking member to permit the top drive to continue to extend longitudinally in a parallel relation to the drilling tower when the linking member pivots between the first and second pivot positions. According to still yet another aspect, the top drive is spaced from the drilling tower by first and second spacings when the linking member is in the fifth and sixth pivot positions, respectively, the first and second spacings extending in a direction that is perpendicular to the first axis; and wherein the second spacing is greater than the first spacing. According to still yet another aspect, the apparatus includes a platform; and a first opening formed in the platform and adapted to be disposed above a wellbore, the first opening defining a third axis that is spaced in a parallel relation from the first axis by the first spacing. According to still yet another aspect, the apparatus includes a second opening formed in the platform and adapted to receive a tubular member, the second opening defining a fourth axis that is spaced in a parallel relation from the first axis by the second spacing. According to still yet another aspect, the apparatus includes at least one actuator coupled to the carriage and the linking member to pivot the linking member between the first and second pivot positions. According to still yet another aspect, the drilling tower extends longitudinally along a first axis when the drilling tower is in the second pivot position; and wherein the apparatus further includes a tubular handling device to position one or more tubular members proximate the drilling tower, the tubular handling device including a first gripper to engage a first tubular member; and a first arm coupled to the first gripper, the first arm defining a second axis that is parallel to the first axis and spaced therefrom in a first direction, the first arm being movable along, and pivotable about, the second axis; and a third axis that is perpendicular to the second axis, the third axis being movable from the second axis in the first direction and movable to the second axis in a second direction opposite the first direction, the first gripper being rotatable, relative to the first arm, about the third axis.
The present disclosure also introduces a method including providing a base; and pivotally coupling a drilling tower to a base, which includes providing a first portion of the drilling tower; pivotally coupling a second portion of the drilling tower to the first portion of the drilling tower; and pivotally coupling the first portion of the drilling tower to the base. According to one aspect, the method includes pivoting the second portion of the drilling tower between first and second pivot positions; and pivoting the drilling tower between third and fourth positions. According to another aspect, the second portion pivots from the first pivot position to the second pivot position in a first pivot direction; and wherein the drilling tower pivots from the third pivot position to the fourth pivot position in a second pivot direction opposite the first pivot direction. According to yet another aspect, the method includes coupling a top drive to the drilling tower; and moving the top drive along each of the first and second portions of the drilling tower when the second portion is in the second pivot position and the drilling tower is in the fourth pivot position. According to still yet another aspect, the method includes pivotally coupling a linking member to each of the first portion and the top drive; and pivoting the linking member between fifth and sixth pivot positions; wherein the top drive defines a first axis; wherein a first spacing is defined between the first axis and the first portion of the drilling tower when the linking member is in the fifth pivot position; wherein a second spacing is defined between the first axis and the first portion of the drilling tower when the linking member is in the sixth pivot position; and wherein the second spacing is greater than the first spacing. According to still yet another aspect, the method includes coupling a first electric motor to the top drive; and employing at least the first electric motor to move at least the top drive and the first electric motor along each of the first and second portions of the drilling tower when the second portion is in the fourth pivot position. According to still yet another aspect, the drilling tower includes a first rack; and wherein the method further includes operably coupling a first pinion to the first electric motor; and engaging the first pinion with the first rack. According to still yet another aspect, the drilling tower further includes a second rack spaced from the first rack in a parallel relation; wherein the method further includes coupling a second electric motor to the top drive; operably coupling a second pinion to the second electric motor; and engaging the second pinion with the second rack; and wherein employing at least the first electric motor to move at least the top drive and the first electric motor along each of the first and second portions of the drilling tower when the second portion is in the fourth pivot position includes employing at least the first and second electric motors to move at least the top drive, the first electric motor, and the second electric motor, along each of the first and second portions of the drilling tower when the second portion is in the fourth pivot position. According to still yet another aspect, the method includes coupling a carriage to the top drive and the first and second electric motors. According to still yet another aspect, the drilling tower extends longitudinally along a first axis; wherein the first and second electric motors are spaced from each other in a direction that is perpendicular to the first axis; and wherein the first and second pinions are spaced from each other in the direction. According to still yet another aspect, the drilling tower extends longitudinally along a first axis; wherein the first and second electric motors are spaced from each other in a first direction that is parallel to the first axis; wherein the first and second pinions are spaced from each other in the first direction and in a second direction that is perpendicular to the first axis; and wherein the method further includes third and fourth pinions engaged with the first and second racks, respectively, wherein the third and fourth pinions are spaced from each other in each of the first and second directions. According to still yet another aspect, the drilling tower extends longitudinally along a first axis; and wherein the method further includes coupling a carriage to the drilling tower; pivotally coupling a linking member to the carriage to permit the linking member to pivot between fifth and sixth pivot positions about a second axis that is perpendicular to the first axis; and pivotally coupling the top drive to the linking member so that the top drive extends longitudinally in a parallel relation to the drilling tower, the top drive being pivotally coupled to the linking member to permit the top drive to continue to extend longitudinally in a parallel relation to the drilling tower when the linking member pivots between the fifth and sixth pivot positions. According to still yet another aspect, the method includes the top drive is spaced from the drilling tower by first and second spacings when the linking member is in the fifth and sixth pivot positions, respectively, the first and second spacings extending in a direction that is perpendicular to the first axis; and wherein the second spacing is greater than the first spacing. According to still yet another aspect, the method includes providing a platform; wherein a first opening is formed in the platform and is adapted to be disposed above a wellbore, the first opening defining a third axis that is spaced in a parallel relation from the first axis by the first spacing. According to still yet another aspect, a second opening is formed in the platform and is adapted to receive a tubular member, the second opening defining a fourth axis that is spaced in a parallel relation from the first axis by the second spacing. According to still yet another aspect, the method includes coupling at least one actuator to the carriage and the linking member to pivot the linking member between the fifth and sixth pivot positions. According to still yet another aspect, the drilling tower extends longitudinally along a first axis when the drilling tower is in the fourth pivot position; and wherein the method further includes employing a tubular handling device to position one or more tubular members proximate the drilling tower, including providing a first gripper; coupling a first arm to the first gripper, the first arm defining a second axis that is parallel to the first axis and spaced therefrom in a first direction, and a third axis that is perpendicular to the second axis; moving the first arm along the second axis; pivoting the first arm about the second axis; moving the third axis from the second axis in the first direction; rotating the first gripper, relative to the first arm, about the third axis; engaging a first tubular member with the first gripper; and moving the third axis, the first gripper and the first tubular member towards the second axis in a second direction opposite the first direction.
The foregoing outlines features of several embodiments so that a person of ordinary skill in the art may better understand the aspects of the present disclosure. Such features may be replaced by any one of numerous equivalent alternatives, only some of which are disclosed herein. One of ordinary skill in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. One of ordinary skill in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions and alterations herein without departing from the spirit and scope of the present disclosure.
The Abstract at the end of this disclosure is provided to comply with 37 C.F.R. §1.72(b) to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
Moreover, it is the express intention of the applicant not to invoke 35 U.S.C. §112, paragraph 6 for any limitations of any of the claims herein, except for those in which the claim expressly uses the word “means” together with an associated function.
This application claims the benefit of and priority to U.S. Provisional Application No. 61/646,686 filed May 14, 2012, entitled “Drilling Rig and Methods,” to Reddy et al., the entire disclosure of which is hereby incorporated herein by reference.
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