1. Field of the Invention
The present invention relates to apparatus for performing earth borehole operations such as drilling and, in particular, to apparatus which can use both coiled tubing and jointed (threaded) pipe.
2. Description of Prior Art
The use of coiled tubing (CT) technology in oil and gas drilling and servicing has become more and more common in the last few years. In CT technology, a continuous pipe wound on a spool is straightened and pushed down a well using a CT injector. CT technology can be used for both drilling and servicing, e.g., workovers.
The advantages offered by the use of CT technology, including economy of time and cost are well known. As compared with jointed-pipe technology wherein typically 30-45 foot straight sections of pipe are threadedly connected one section at a time while drilling the wellbore, CT technology allows the continuous deployment of pipe while drilling the well, significantly reducing the frequency with which such drilling must be suspended to allow additional sections of pipe to be connected. This results in less connection time, and as a result, an efficiency of both cost and time.
However, the adoption of CT technology in drilling has been less widespread than originally anticipated as a result of certain problems inherent in using CT in a drilling application. For example, because CT tends to be less robust than jointed-pipe for surface-level drilling, it is often necessary to drill a surface hole using jointed-pipe, cement casing into the surface hole, and then switch over to CT drilling. Additionally, when difficult formations such as gravel are encountered down-hole, it may be necessary to switch from CT drilling to jointed-pipe drilling until drilling through the formation is complete, and then switch back to CT drilling to continue drilling the well. Similarly, when it is necessary to perform drill stem testing to assess conditions downhole, it may again be necessary to switch from CT drilling to jointed-pipe drilling and then back again. Finally, a switch back to jointed pipe operations is necessary to run casing into the drilled well. In short, in CT drilling operations it is generally necessary for customers and crew to switch back and forth between a CT drilling rig and a jointed-pipe conventional drilling rig, a process which results in significant down-time as one rig is moved out of the way, and the other rig put in place.
Another disadvantage of CT drilling is the time consuming process of assembling a (bottom-hole-assembly (BHA)—the components at the end of the CT for drilling, testing, well servicing, etc.), and connecting the BHA to the end of the CT. Presently, this step is performed manually through the use of rotary tables and make-up/breakout equipment. In some instances, top drives are used but the CT injector and the top drive must be moved out of each others way i.e., they cannot both be in line with the borehole. Not only does this process result in costly downtime, but it can also present safety hazards to the workers as they are required to manipulate heavy components manually.
To address the problems above associated with the use of CT technology and provide for selective and rapid switching from the use of a CT injector to a top drive operation, certain so-called “universal” or “hybrid” rigs have been developed. Typical examples of the universal rigs, i.e., a rig which utilizes a single mast to perform both top drive and CT operations, the top drive and the CT injector being generally at all times operatively connected to the mast, are shown in United States Patent Publication 2004/0206551; and U.S. Pat. Nos. 6,003,598, and 6,609,565. Thus, in U.S. Publication 2004/0206551 there is disclosed a rig adapted to perform earth borehole operations using both CT and/or jointed-pipes, the CT injector and a top drive being mounted on the same mast, the CT injector being selectively moveable between a first position wherein the CT injector is in line with the mast of the rig and hence the earth borehole and a second position wherein the CT injector is out of line with the mast and hence the earth borehole.
In all the systems disclosed in the aforementioned patents, the top drive and the CT injector are two separate units. Accordingly, as disclosed in all of the aforementioned patents, various techniques are disclosed for selectively positioning the CT injector or the top drive over center of the wellbore depending on whether CT operations are being conducted or jointed pipe operations are being conducted.
In one embodiment of the present invention there is provided an apparatus for conducting earth borehole operations comprising a carrier, base or substructure, a mast mounted on the carrier and an integrated top drive/CT injector unit (integrated unit) mounted on the mast for longitudinal movement therealong. In one aspect, the integrated unit comprises two assemblies, a bottom portion or module which comprises the top drive and an upper portion or module which comprises the CT injector. The bottom module comprising the top drive has an opening therethrough or therealong through which CT from the top module comprising the CT injector can pass when it is desired to conduct CT operations.
In another aspect of the present invention, there is provided an integrated unit as described above further comprising a gooseneck or guide which is releasably connected to the CT injector module of the integrated unit and which can be mounted on the mast and movable between a first position wherein CT passing through the gooseneck can be stabbed into the CT injector module such that the CT issuing therefrom is substantially inline with the axis of the wellbore, and a second position wherein the gooseneck can be moved laterally or rotatably with respect to the integrated unit and hence the mast such that the CT held by the gooseneck is out of line with the axis of the wellbore.
Referring first to
Carrier 10 includes a work platform 20 and a sub-platform 22 on which are mounted a pair of pillow blocks 24, only one of which is shown, a reel 26 of CT being journaled in pillow blocks 24. CT 28 played off of reel 26 extends up to and is gripped by a gooseneck/guide 30 for a purpose described more fully hereafter. As is well known, carrier 10 can be of the wheeled variety having a tongue 11 for connection to a tractor or the like whereby carrier 10 can be moved from site to site. In this regard, it will be appreciated that mast 14 can pivot from the vertical position shown in
Movably, e.g., slidably, mounted on mast 14 along tracks 15, 17, is an integrated top drive/CT injector unit 40. The integrated unit 40 comprises a lower, top drive module 42 and an upper, CT module 44. As seen with reference to
Integrated unit 40 is integrated in the sense that the top drive module 42 and the CT injector module 44 are not separate units but are mechanically joined to one another and move in unison longitudinally along the mast 14. To accomplish such movement, one or more cables 48 attached to integrated unit 40 run through the crown sheaves 18 to a draw works 50 mounted on platform 22. In this manner, by operation of draw works 50, integrated unit 40 can be moved longitudinally along mast 14. In the embodiment shown in FIG. 1, it can be seen that the CT 28 is stabbed into CT injector module 44, and extends through top drive portion 44 downwardly through a wellhead 54 into a wellbore (not shown). Thus,
With reference to
Reference is now made to
Once the CT has been removed from the CT module 44 as depicted in
Turning now to
In the depiction shown in
Turning now to
As described above with respect to the embodiments shown in
It will be appreciated that carrier 10 can be self-propelled. Furthermore, the carrier can comprise a stationary structure as, for example, a skid or the like, which can be raised and placed on a trailer or other transport vehicle for movement to another site if desired. It will also be appreciated that the apparatus of the present invention can be mounted on an offshore platform via a skid or other substructure on which the mast and other components are mounted. As noted above, the top drive module 42 is provided with a longitudinal opening 43 extending therethrough for passage of the CT 28. Obviously, the integrated unit could be designed such that top drive module 42 was slotted so that rather than a longitudinal opening being provided in the top drive unit 42, the CT 28 would pass through the slot in the top drive module 42.
Although not shown, it will be understood that the integrated unit 40 could be carried on a suitable cradle or the like attached to the cables 48 for movement of the integrated unit 40 longitudinally along the mast 14.
While it is conceivable that the integrated unit 40 could have a monolithic housing, for purposes of servicing the respective modules, typically the top drive module 42 and the CT module 44 would be separate, connected housings which would permit selective access to one of the modules as desired. It will also be understood that suitable structural members can connect the top drive module 42 with the CT module 44 in such a manner that they move as a one piece unit. The term “integrated” as used with respect to the integrated CT injector/top drive of the present invention is intended to encompass a structure be it monolithic, separate, attached modules or the like which, whatever the form, can be moved longitudinally along the mast as a single unit as opposed to the CT injector and the top drive being independently movable with respect to one another along the mast. Further, although the integrated unit of the present invention has been described with respect to the CT module or portion being above the top drive module or portion, it is within the scope of the present invention that the relative positions of the CT injector and the top drive could be reversed, e.g., with the top drive above the CT injector. While such a configuration presents greater difficulties from an engineering standpoint, it would nonetheless be possible to construct such an integrated unit. One of the advantages of the integrated unit of the present invention is the fact that the CT injector and the top drive could share common components, e.g., hydraulic systems, planetary gear systems, and other pneumatic, hydraulic or mechanical systems which are or could be used either in a CT injector or a top drive.
It can be seen that the present invention provides a unique, universal rig which can selectively handle and run different types of pipe, CT, and other earth borehole equipment thereby eliminating the need for two rigs—one rig to use a top drive in the conventional manner and a separate CT injector unit to perform CT operations.
As described above, the guide 30 can be mounted either on a trolley or carriage which moves along tracks transverse to and affixed to columns 14a and 14b of mast 14 or on a frame attached to mast 14 which allows guide 30 to pivot or rotate as described. In this manner, the guide 30 can be selectively, laterally or rotatably moved relative to the mast, e.g., from a first position where the guide can be attached to the CT injector and the free end 90 of the CT 28 can be stabbed into the CT module 44 when CT operations are employed to a second position where, once the CT is removed from the CT module 44, the CT from the guide will be out of alignment with the CT module 44 so as to permit the top drive module 42 to perform jointed pipe operations.
It will also be apparent that the guide 30 need not be mounted on a trolley/track or rotation system secured to the mast. For example, a separate crane, e.g., jib crane, could be used to hold the guide 30 in a position such is shown in
The foregoing description and examples illustrate selected embodiments of the present invention. In light thereof, variations and modifications will be suggested to one skilled in the art, all of which are in the spirit and purview of this invention.
This application claims the priority of U.S. Provisional Application No. 60/737,611 filed on Nov. 17, 2005, the disclosure of which is incorporated herein by reference for all purposes.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US2006/044500 | 11/16/2006 | WO | 00 | 5/16/2008 |
Number | Date | Country | |
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60737611 | Nov 2005 | US |