1. Field of Invention
The present invention pertains to a method and apparatus for stabbing tubular goods suspended within the derrick of a rig or other structure.
2. Description of Related Art
After a well has been drilled to a desired depth, pipe called casing is frequently installed in the well and cemented in place. Such casing is usually inserted into a well in a number of separate sections of substantially equal length called “joints.” The joints are typically screwed together or otherwise joined end-to-end at the rig floor of a drilling rig in order to form a substantially continuous “string” of pipe that reaches downward into the ground. As the bottom or distal end of the pipe string extends further into a well, additional sections of pipe are added to the upper end of the pipe string on the drilling rig.
The process of installing a string of pipe in a well is typically commenced by lowering a first section of pipe into a wellbore at the rig floor, and suspending said section of pipe in place using a set of “lower slips.” In this position, the uppermost end of said first section of pipe is generally situated a few feet above the rig floor. Thereafter, a second section of pipe is lifted within a drilling rig derrick and suspended vertically within said derrick; the second section of pipe is then positioned in linear alignment above the first section of pipe which was previously run into the well. The lower end of said second section is then connected to the upper end of said first section. Once joined, the two sections of pipe are lowered further into the well and hung in place within the well using lower slips. This process is repeated until the desired length of pipe is run into the well.
It is generally the custom of the oil and gas industry to insert sections of pipe into a wellbore so that male or “pin” end threaded connections face downward, while female or “box” end connections face upward. Thus, when individual joints of pipe are added to a string of pipe in a well in the manner described above, the pin end of the second/upper joint of pipe (which is suspended within a derrick) is typically “stabbed” into the box end of the lower joint (which is suspended in the well bore). The upper joint is then rotated so that the mating threads of the two joints join together. However, this connection process can be reversed if needed.
On conventional drilling rigs (i.e., those rigs not equipped with top drive systems), a joint of casing is typically hoisted into the derrick from a v-door or pipe rack using an auxiliary lifting system. Such joint is linearly aligned with the pipe suspended within the well below, stabbed into the upward-facing box end connector of such lower pipe, and rotated using power tongs to make up the threaded connection. Thereafter the traveling block of the rig is lowered to a point near the upper end of such upper pipe joint, so that elevators attached to said traveling block can grip said upper pipe joint. Although many functions in this process can be automated, personnel must frequently be stationed in an elevated position within the derrick (such as on a board or the like), and must reach out toward the center of the derrick to perform certain tasks such as aligning the elevators with the upper end of the pipe joint, or manipulating the hanging pipe and/or elevators.
On rigs equipped with top drive systems, running tools (RT) have become increasingly popular in recent years in connection with the installation of casing into wells. Such RT's can be used to pick up and stab joints of casing, eliminating the necessity for personnel to be located at an elevated location on a rig, such as on a casing stabbing board in the derrick.
In most cases, a RT is connected immediately below a rig's top drive unit prior to commencement of casing operations. A single-joint elevator, supported by a RT, is typically used to lift individual joints of casing from a V-door or pipe rack to a vertical suspended position within a derrick. After being lifted into this position, said joint of casing is stabbed into an upward-facing joint of pipe already installed in a well and suspended from lower “spider” slips at the rig floor. At that point, the top drive and attached RT are lowered until the RT “stabs into” the bore of the new joint of pipe being added. The slips of the RT are set on the joint of casing, and the top drive is actuated to apply the required torque (through the RT) to make up the casing connection. At times, during the lowering of the pipe string into the well, the pipe string can be rotated and/or reciprocated from the top of the string using the top drive to facilitate installation in the well.
Numerous devices have been developed to assist in the alignment and interconnection of joints of elongated pipe and other tubular goods used in the drilling and completion of oil and gas wells. Many of these devices employ means for gripping a joint of pipe while it is suspended within a derrick. Force is then applied to the suspended pipe joint until it is oriented in linear alignment with pipe which has already been inserted in such wellbore. Such devices are typically cumbersome and heavy, and must be attached to a rig derrick or other support structure that was not specifically designed for supporting such equipment.
Thus, there is a need for a method and apparatus for stabbing tubular goods that are suspended at high elevations including, without limitation, in the derrick of a drilling rig. The method and apparatus for stabbing tubular goods should reduce problems associated with current methods of stabbing pipe within a drilling rig derrick. The method and apparatus should be automated, reliable, effective, versatile, and should reduce or eliminate the need for stationing personnel at unsafe locations.
In the preferred embodiment, the present invention comprises a substantially planar plate member having a central bore or aperture. When attached to a set of slip-type elevators, said central bore or aperture is positioned in alignment with the bore of said elevators. At least one cylinder is connected to said plate member; in the preferred embodiment, two cylinders are employed and positioned generally lateral to said elevators. Said cylinders, which can be hydraulically or pneumatically actuated, can be extended or retracted in a substantially axial direction. Further, such cylinders can be simultaneously or independently actuated to adjust the positioning of pipe connected to said cylinders.
In the preferred embodiment, said cylinders can be hydraulic or pneumatic cylinders. When utilized in connection with conventional slip-type elevators or RT's, the apparatus of the present invention can be used to pull a joint of pipe upward into mating relationship with a nose of a fill-up tool, stabbing connection or the like. At that point, said slip-type elevators can be lowered over the pipe in order to grip said pipe. Similarly, when an RT is being used, said RT can be lowered until it is able to grip the pipe (either internally or externally, depending on the particular RT being used).
Advantages of the present invention include, but are not limited to, the following:
The foregoing summary, as well as any detailed description of the preferred embodiments, is better understood when read in conjunction with the drawings and figures contained herein. For the purpose of illustrating the invention, the drawings and figures show certain preferred embodiments. It is understood, however, that the invention is not limited to the specific methods and devices disclosed in such drawings or figures.
Referring to
Cylinder assembly 30 generally comprises piston 32 which is movably disposed within outer barrel 31. Attachment member 33 having eyelet 34 is disposed at the distal end of piston 32. Similarly, cylinder assembly 20 generally comprises piston 22 which is movably disposed within outer barrel 21. Attachment member 23 having eyelet 24 is disposed at the distal end of piston 22. Cylinder assemblies 20 and 30 can be hydraulically or pneumatically actuated, such that pistons 22 and 32 can be axially extended or retracted relative to barrels 21 and 31, respectively. Further, cylinder assemblies 20 and 30 can beneficially be simultaneously or independently actuated.
In the preferred embodiment, bore 11 extending through substantially planar plate member 10 includes at least one notch or cut-out section 12. When installed on conventional slip-type elevators (as described in detail below), said at least one cut-out section 12 permits slips to open and close without interference from plate member 10. Further, threaded bolts or other fasteners can be installed within apertures 13 to connect said plate member 10 to a set of elevators.
Still referring to
Cylinder assembly 30 generally comprises outer barrel 31 and piston 32. Attachment member 33 having eyelet 34 is disposed at the distal end of piston 32. Similarly, cylinder assembly 20 generally comprises outer barrel 21 and piston 22. Attachment member 23 having eyelet 24 is disposed at the distal end of piston 22. In the embodiment depicted in
Still referring to
Piston 32 of cylinder assembly 30 extends from outer barrel 31, while piston 22 of cylinder assembly 20 extends from outer barrel 21. As depicted in
Extension link members 40 are attached to eyelets 24 and 34 at their upper ends. The lower ends of said extension link members are connected to single joint elevator 50 which is gripping pipe section 300. As depicted in
Referring back to
Thereafter, a (second) section of pipe 300 is gripped by single joint elevator 50 and lifted within drilling rig derrick 210, typically by raising top drive unit 220. Said single joint elevator 50 is connected to cylinder assemblies 20 and 30 via extension link members 40. In this position, pipe section 300 is suspended vertically within derrick 210 in axial alignment with pipe section 310 that was previously installed in said well.
Referring to
As depicted in
As discussed herein and as depicted in the drawings, stabbing apparatus 100 comprises substantially planar plate member 10. However, it is to be observed that in some circumstances, said substantially planar plate member 10 may not easily or efficiently mate with components of equipment embodying certain designs (such as, for example, casing running tools). In such instances, it may be possible to utilize the other elements of stabbing tool 100, but not said substantially planar plate member, without departing from the scope of the present invention.
Referring to
Stabbing apparatus 100 of the present invention can replace bulky, expensive, cumbersome and dangerous existing stabbing devices including, without limitation, those used in connection with casing installation operations and RT's. Further, stabbing apparatus 100 can be used with virtually all elevator designs, and can conveniently retrofit to virtually any and all existing casing and tubing slip-type elevators. Importantly, stabbing apparatus 100 reduces or eliminates the need for stationing personnel at elevated or unsafe positions including, without limitation, within a drilling rig derrick. Moreover, stabbing apparatus 100 and the method described herein allows a driller/operator to lower pipe to a make-up position without requiring pipe to be stabbed from a driller's console or other difficult remote location.
The above-described invention has a number of particular features that should preferably be employed in combination, although each is useful separately without departure from the scope of the invention. While the preferred embodiment of the present invention is shown and described herein, it will be understood that the invention may be embodied otherwise than herein specifically illustrated or described, and that certain changes in form and arrangement of parts and the specific manner of practicing the invention may be made within the underlying idea or principles of the invention.
Number | Date | Country | |
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61392097 | Oct 2010 | US | |
61421419 | Dec 2010 | US |