The present disclosure is related to the field of oil and gas well completions and workovers, in particular, a system for moving an entire completion or workover rig and workstring without disassembling the rig or laying down the workstring.
It is typical for a number of oil and gas wells to be drilled from a central location, known as a “well pad” in order to reduce the footprint of multiple well locations and make the overall well construction process more efficient. After each well is drilled, it must be “completed” in order for production of oil or gas to begin. After production has commenced, it is common that the wells may need a “workover” to enhance production and/or repair a subsurface problem. A typical completions/workover rig moves tools and equipment in and out of the well by assembling or disassembling a workstring in sections that can be contained in a rack rather than laying each joint down each time. It is much more time efficient to store the workstring vertically in the rack than lay each piece down.
When working on a well pad, each well is in relatively close proximity. In most cases, when a completions/workover rig moves from one well to another on a well pad, the workstring must be completely dismantled and laid down, the rig must be rigged out, moved, and rigged back up, and the workstring picked back up and re-assembled. Laying down and picking up the workstring, as well as the rig out and rig up of the rig are high risk operations that lead to personnel injuries and damaged equipment. Typical completions/workover rigs have a series of guy-lines that attach to the mast and the racking board to provide stability to resist forces in the mast due to wind loading and hoisting loads. The guy-lines are either attached to ground anchors or to outriggers in a specified pattern.
It is, therefore, desirable to provide a system that enables the rig and workstring to be moved from one well to another with the rig standing and the workstring stored vertically.
A system for moving the completions/workover rig and vertically stored workstring without dismantling is provided. The system can comprise of a platform that can be placed in a position relative to the first well to be completed or worked over on a pad prior to the completions/workover rig. The rig can be initially rigged up on top of the platform, and the workstring can be picked up and assembled in order to complete or workover the first well. The platform can include a ramp incorporated on one end that the rig can back up onto in addition to outriggers that are designed to act as guy-line anchors to counteract mast over-turning loads, as well as a stand with a racking system where the workstring can be stored vertically. It is critical to ensure that the loads imparted on the mast do not exceed the design loading of the rig which is known by comparing to the maximum allowable wind loading. The outriggers can move with the entire system; therefore, the mast loading is acceptable.
Typically, when a completions/workover rig pulls the workstring from a well, it is racked in sections and set on the ground on the side of the wellhead that is opposite the main rig. The workover rig walking system can comprise a platform that the workstring can be set on that keeps the workstring elevated so that as the rig can move away from the well, the workstring will not interfere with the wellhead. A lower racking system that can be actuated hydraulically can be deployed prior to moving the platform that stabilizes the workstring to counteract acceleration forces and minimize the loads that would be transferred into the rig. The lower racking system can comprise a series of pipe clamps that can be folded to a stand-by position during conventional workover operations. The pipe clamps can be folded into place as the workstring is being pulled out of the well the last time before a rig move. Once all of the workstring is in place, the lower racking system can be raised hydraulically to a point that will optimize its effectiveness, and then the clamps can be squeezed onto the workstring. Telescoping cross braces can be attached to the lower racking area and to the main beam of the workover rig walking system to provide stabilization and to minimize the forces of acceleration transferred into the mast during walking operation.
The platform can comprise outriggers that act as guy-line anchors to counteract mast over-turning loads when the rig is being operated and when the rig is being moved between wells. The platform can comprise a number of walking assemblies that can lift the complete platform, rig and workstring and then move it in a linear direction. The walking assemblies can be turned in order to move the platform in the desired direction. The walking assemblies can be controlled with a system to ensure that vertical movement is equal to keep the platform level, and to keep the rig and workstring vertical while being lifted. The control system can also be deployed to ensure that horizontal movement is coordinated, and to minimize acceleration loads.
In some embodiments of the system, an isolation system can be utilized between the upper workstring rack and the rigs hoisting mast that can minimize acceleration loads being transferred into the mast from the movement of the workstring.
Broadly stated, in some embodiments, a walking system can be provided for a workover rig or completion rig for use on a wellhead with a workstring assembled from a plurality of tubulars, the workover rig or completion rig disposed on a motor vehicle, the workover rig or completion rig further comprising a mast and an upper racking board, the walking system comprising: a main platform comprising vehicle tracks configured for the motor vehicle to travel along; ramps disposed at a first end of the main platform, the ramps operatively coupled to the vehicle tracks, the ramps configured for the motor vehicle to travel up the ramps onto the vehicle tracks; a set back platform disposed at a second end of the main platform, the set back platform comprising an elevated workstring platform wherein the elevated workstring platform is configured for storing the plurality of tubulars in combination with the upper racking board; a base beam disposed on the main platform between the first end and the second end of the main platform, the base beam comprising one end extending substantially perpendicularly from one side of the main platform, the base beam further comprising an opposing end extending substantially perpendicularly from an opposing side of the main platform; and a plurality of walking assemblies disposed on the main platform and the base beam, the plurality of walking assemblies configured to raise the combination of the walking system and the rig and move said combination in a lateral direction.
Broadly stated, in some embodiments, the elevated workstring platform can further comprise front supporting members and rear supporting members operatively coupled the elevated workstring platform to the main platform and the base beam, the front and rear supporting members configured to support the elevated workstring platform at a height above the wellhead.
Broadly stated, in some embodiments, each of the ends of the base beam can comprise a guy anchor configured for anchoring guy-lines from the mast and from the upper racking board.
Broadly stated, in some embodiments, each of the plurality of walking assemblies can comprise: a mounting flange operatively coupled to the main platform; a lifting cylinder, an upper end of the lifting cylinder operatively coupled to the mounting flange; a walking foot, the walking foot comprising a roller raceway; a roller assembly operatively coupled to a lower end of the lifting cylinder; and a shift cylinder operatively coupling the roller assembly to the walking foot, wherein the roller assembly travels along the roller raceway when the shift cylinder extends and retracts.
Broadly stated, in some embodiments, the walking system can further comprise: at least one racking board isolator disposed on the upper racking board; at least one mast isolator disposed on the mast; and a coupler operatively coupling the at least one racking board isolator to the at least one mast isolator.
Broadly stated, in some embodiments, one or both of the at least one racking board isolator and the at least one mast isolator can comprise one or more of a spring, a damper and a spring-damper combination.
Broadly stated, in some embodiments, the elevated workstring platform can comprise a pipe stabilization system, comprising: a clamp frame; a plurality of workstring clamps configured to receive one or more of the tubulars; and a plurality of clamping cylinders operatively coupling the plurality of workstring clamps to the clamp frame, the plurality of clamping cylinders configured to tighten to clamp the tubulars to the clamp frame, the plurality of clamping cylinders further configured to loosen wherein the tubulars are released from the plurality of workstring clamps.
Broadly stated, in some embodiments, the clamp frame can further comprise a plurality of frame cylinders configured to raise and lower the clamp frame relative to the elevated workstring platform.
Broadly stated, in some embodiments, the walking system can further comprise a plurality of leveling cylinders configured for leveling the main platform and the base beam.
In this description, references to “one embodiment”, “an embodiment”, or “embodiments” mean that the feature or features being referred to are included in at least one embodiment of the technology. Separate references to “one embodiment”, “an embodiment”, or “embodiments” in this description do not necessarily refer to the same embodiment and are also not mutually exclusive unless so stated and/or except as will be readily apparent to those skilled in the art from the description. For example, a feature, structure, act, etc. described in one embodiment may also be included in other embodiments but is not necessarily included. Thus, the present technology can include a variety of combinations and/or integrations of the embodiments described herein.
Referring to
In some embodiments, clamp frame 107, as shown in
In some embodiments, the plurality of walking assemblies 105 can be deployed to linearly move workover rig walking system 100 in a horizontal manner as shown in
Upon successfully raising workover rig walking system 100 by lift cylinders 123, system 10 can then traverse in a horizontal direction by actuation of shift cylinders 121.
In some embodiments, walking assemblies 105 can comprise the capability to be rotated about the axis of lift cylinder 123, as illustrated in
In some embodiments, as depicted in
In some embodiments, roller raceway 126 can be mounted on top of walking foot 120 and can provide a secure surface for the movement of roller assembly 122.
Referring to
In some embodiments, this isolation of upper racking board 203 from mast 202 can minimize acceleration loads from the movement of workstring 210 during operation of workover rig walking system 100. In some embodiments, racking board isolator 207 and mast isolator 205 can comprise fixed stop 208, spring dampers 209 and clevis 216, where spring dampers 209 can act on fixed stop 208 and clevis 216 to keep clevis 216 centralized when no external forces are applied to upper racking board 203. When an external force is applied to upper racking board 203, one spring damper 209 can compress while the opposite spring damper 209 can decompress. In some embodiments, spring dampers 209 can impart a specified force into mast 202 such that mast 202 will not be overloaded and fail. When the external force is removed, spring dampers 209 can equalize and return clevis 216 and upper racking board 203 to its original position.
Transportability of workover rig walking system 100 is of importance when moving from one site to another and can be achieved with the efficient separation of each sub-structure of the system.
Once workover rig walking system 100 is assembled and properly positioned in relation to wellhead 110, workover rig 200 can be positioned in front of system 100, moved onto main platform 101 and deployed as shown in
Referring to
In some embodiments, clamping cylinders 113 and workstring clamps 114 can be rotated out of the way when workover rig 200 is being used in normal operation, as shown in
Although a few embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications can be made to these embodiments without changing or departing from their scope, intent or functionality. The terms and expressions used in the preceding specification have been used herein as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding equivalents of the features shown and described or portions thereof, it being recognized that the invention is defined and limited only by the claims that follow.
This application claims priority from U.S. Patent Application Ser. No. 62/798,718 entitled “Walking System for a Completion or Workover Rig” filed on Jan. 30, 2019, in the names of Harold James Miller et al., which is hereby incorporated by reference, in entirety, for all purposes.
Number | Date | Country | |
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62798718 | Jan 2019 | US |