Patent Application
20070012449
None.
Not applicable.
Not applicable.
The present invention relates generally to apparatus and methods for cutting a wireline or other umbilical disposed within a well bore. In one aspect, the present invention relates to a wireline cutter and methods of use. In another aspect, the present invention relates to one-trip systems and methods for cutting both a coiled tubing string and a wireline disposed therein when the coiled tubing and/or wireline breaks or becomes stuck within a well bore.
Historically, hydrocarbons such as oil and gas were produced by drilling a substantially vertical well bore from a surface location above the formation to the desired hydrocarbon zone at some depth below the surface. However, modern drilling technology and techniques allow for the drilling of well bores that deviate from vertical. Therefore, deviated well bores may be drilled from a convenient surface location to the desired hydrocarbon zone.
During such drilling or other well bore operations, it may be economically infeasible or otherwise undesirable to use jointed drill pipe. Therefore, apparatus and methods have been developed for performing such operations using coiled tubing, which is a single length of continuous, unjointed tubing spooled onto a reel for storage in sufficient quantities to exceed the length of the well bore. The coiled tubing may include one or more umbilicals disposed therein, such as a wireline to provide power and data communications to and from a drilling assembly, a hose for injecting chemicals into the well bore, or a heating string, for example.
When drilling a vertical well bore or a sidetracked well bore using a coiled tubing drill string, many circumstances can arise where it becomes necessary to cut the coiled tubing and remove it from the well bore. This may occur, for example, when the drilling assembly gets stuck during drilling, and the coiled tubing must be cut away from the drilling assembly to facilitate fishing, jarring, or other operations.
Under such circumstances, the coiled tubing that extends into the well bore, as well as any umbilicals installed therein, must be cut away from the coiled tubing reel at the surface and released into the well bore. Then, various apparatus and methods are available for cutting the coiled tubing drill string from the drilling assembly and retrieving it from the well bore. One such apparatus comprises a coiled tubing cutter, such as the Cutting Overshot device sold by Thru-Tubing Technology, Inc. of Scott, La. In operation, the Cutting Overshot device is attached to a work string and then lowered to receive the coiled tubing within a tubular housing of the device. When the Cutting Overshot device reaches the desired cutting location on the coiled tubing, the work string is raised to apply an upward force on the Cutting Overshot device, thereby shearing a plurality of set screws, and forcing a cutting grapple into the coiled tubing to cut the tubing. Although the Cutting Overshot device is very effective for cutting the coiled tubing drill string, it is not configured to cut a wireline or other umbilical running inside the coiled tubing. Therefore, at least a second trip into the well bore is required to retrieve and/or cut the wireline and other umbilicals.
There are other circumstances in which a wireline might be stuck within a coiled tubing string in a well bore. For example, a wireline may be used as a work string to lower a cutting device into the coiled tubing that is stuck in the well bore. However, if the wireline cutting device fails, and/or the wireline will not release, the wireline may break, thereby leaving both the stuck coiled tubing with the stuck wireline disposed therein in the well. Under this scenario, a first trip would be made to cut the coiled tubing, such as with the Cutting Overshot device described above, and then a second trip would be made to cut the wireline. Thus, a need exists for apparatus and methods to cut both a coiled tubing and a wireline disposed therein in one trip into the well bore.
There are also circumstances wherein a wireline not associated with a coiled tubing string may be stuck in a well bore, such as when conducting a wireline fishing operation to retrieve a drilling assembly or other downhole tool. In this type of operation, after the coiled tubing has been cut and retrieved from the well bore, a wireline work string is lowered into the well bore with a fishing device disposed at the lower end thereof for catching the drilling assembly or other tool that is stuck in the well bore. However, if the fishing device catches the fish, but the wireline cannot pull it loose, the wireline may break. Then another trip would be required to cut the wire and retrieve it.
Conventionally, fishing tools, such as a wire grab or a rope spear, for example, with barbs disposed on the end thereof, have been used to cut and/or retrieve a wireline that is either stuck in the well bore or simply disconnected from the surface. The fishing tool is run into the well bore past the upper end of the wireline, then rotated to wrap the tool around the wireline and grab the wireline with the barbs. The wireline may also be “bird nested” by pushing it down within the well bore before rotating the fishing tool to thereby tangle the wireline and make it easier to grab with the barbs. Once the wireline has been grabbed by the fishing tool, an upward force is exerted on the fishing tool to either retrieve an unstuck wireline or cut a stuck wireline. However, a need exists for apparatus and methods that will efficiently and effectively cut through a wireline within a well bore.
In one aspect, the present disclosure relates to a wireline cutter comprising a primary housing with a first axial bore configured to receive a wireline positioned within a well bore, and a first blade mounted within the primary housing and operable to cut the wireline. The first blade may comprise teeth operable to grip and cut the wireline. In an embodiment, the wireline cutter further comprises a torsional spring, which biases the first blade to a closed position extending radially across the first axial bore. The first blade cuts the wireline in the closed position.
In another embodiment, the wireline cutter further comprises one or more modular housings, wherein each of the one or more modular housings comprises another axial bore configured to receive the wireline, and another blade mounted within the modular housing and operable to cut the wireline. The wireline cutter may further comprise a plurality of set screw sockets disposed in a wall of the primary housing, and a plurality of set screw bores disposed in a wall of each of the one or more modular housings, wherein the set screw sockets are spaced apart circumferentially, and wherein the set screw bores are spaced apart circumferentially to correspond with the spacing of the set screw sockets. The set screw cavities and the set screw bores enable rotational adjustability when connecting the primary housing and a modular housing. In an embodiment, the wireline cutter further comprises a plurality of set screw cavities disposed in the wall of each of the one or more modular housings. The set screw cavities and the set screw bores in each of the modular housings enable rotational adjustability when connecting two modular housings. In another embodiment, the primary housing is further configured to receive an umbilical positioned within the well bore, and the first blade is operable to cut the umbilical.
In another aspect, the present disclosure relates to a method of cutting a wireline in a well bore comprising running a wireline cutter into the well bore, receiving the wireline within the wireline cutter, and cutting the wireline with the wireline cutter. The method may further comprise pushing the wireline against an internal wall of the wireline cutter. In an embodiment, the cutting step comprises actuating at least one blade of the wireline cutter. The actuating step may comprise moving the at least one blade into engagement with the wireline, gripping the wireline with the at least one blade, and exerting a force on the at least one blade sufficient to cut the wireline. In an embodiment, the cutting step comprises actuating a plurality of blades spaced apart axially along the wireline cutter, and the method may further comprise circumferentially aligning the plurality of blades, or circumferentially staggering the plurality of blades at different angles.
In yet another aspect, the present disclosure relates to a one-trip cutting system for use in a well bore comprising a wireline cutter, and a coiled tubing cutter.
In still another aspect, the present disclosure relates to a method for cutting, within a well bore, a coiled tubing with a wireline disposed therein comprising running a system comprising a wireline cutter and a coiled tubing cutter into the well bore, cutting the coiled tubing with the coiled tubing cutter, and cutting the wireline with the wireline cutter, wherein both cutting steps are performed in one trip into the well bore. In an embodiment, the method further comprises extending the coiled tubing into the wireline cutter, pushing a blade of the wireline cutter to an open position using the coiled tubing, removing the coiled tubing from engagement with the blade, exposing the wireline, and moving the blade into a wireline cutting position.
Other aspects and advantages of the invention will be apparent from the following description and the appended claims. The various characteristics described above, as well as other features, will be readily apparent to those skilled in the art upon reading the following detailed description, and by referring to the accompanying drawings.
For a more detailed description of the present invention, reference will now be made to the accompanying drawings, wherein:
Certain terms are used throughout the following description and claims to refer to particular assembly components. This document does not intend to distinguish between components that differ in name but not function. In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . ”
Reference to up or down will be made for purposes of description with “up”, “upper”, or “upstream” meaning toward the earth's surface or toward the entrance of a well bore; and “down”, “lower”, or “downstream” meaning toward the bottom or terminal end of a well bore.
In the drawings, the cross-sectional and elevational side views of the wireline cutter should be viewed from left to right, with the upstream end at the left of the drawing and the downstream end at the right of the drawing.
Various embodiments of methods and apparatus for cutting coiled tubing and a wireline (or other umbilical) disposed therein in one trip into the well bore, and various embodiments of a wireline cutter, will now be described with reference to the accompanying drawings, wherein like reference numerals are used for like features throughout the several views. There are shown in the drawings, and herein will be described in detail, specific embodiments of one-trip coiled tubing and wireline cutter systems, as well as wireline cutters, with the understanding that this disclosure is representative only, and is not intended to limit the invention to those embodiments illustrated and described herein. The embodiments of the apparatus disclosed herein may be utilized in any type of coiled tubing and wireline operation. It is to be fully recognized that the different teachings of the embodiments disclosed herein may be employed separately or in any suitable combination to produce desired results.
The drilling assembly 200, which includes a drilling motor 205 and a drill bit 210, connects to the lower end of the coiled tubing 150 and extends into the deviated well bore 170 being drilled. The drilling motor 205 operates the drill bit 210, which cuts into the deviated well bore wall 175. The drilling motor 205 is powered by drilling fluid pumped from the surface 10 through the coiled tubing 150. The drilling fluid flows out through the drill bit 210, and into the well bore annulus 165 back up to the surface 10.
As drilling progresses, it is not uncommon for the drilling assembly 200 and/or the coiled tubing 150 to become stuck within the deviated well bore 170, as schematically depicted in
As best depicted in
The primary housing 410 includes an axial bore 405 extending therethrough comprising a larger diameter bore 412 that reduces 414 to a smaller diameter bore 416. Similarly, the modular housing 420 includes an axial bore 425 extending therethrough comprising a larger diameter bore 422 that reduces 424 to a smaller diameter bore 426. The axial bores 405, 425 of the housings 410, 420 align to provide an axial throughbore in the wireline cutter 400.
The blades 500 are mounted via hinge pins 440 to the housings 410, 420. A torsional spring 450 wraps around each hinge pin 440, and one leg 452 of the spring 450 extends along the blade 500, while another leg 454 of the spring 450 extends axially along the respective housing 410, 420. The torsional springs 450 bias the blades 500 to the closed position shown in
In the embodiment shown in
In the configuration shown in
Further, because the lower housing 420 is modular, a plurality of modular housings 420 may be connected to one another to provide a longer wireline cutter 400 and additional blades 500 for cutting the wireline 190. Thus, these modular housings 420 may further comprise a plurality of set screw cavities 429 on the pin end 423 thereof corresponding to the set screw bores 428 on the box end 421 of the next modular housing 420 to be connected. Thus, the set screw cavities 429 and the corresponding set screw bores 421 provide rotational adjustability between two connected modular housings 420.
Accordingly, while the wireline cutter 400 depicted in
Referring now to
As best shown in
In operation, when the one-trip cutting system 250 shown in
As the blades 500 close, they push the wireline 190 against the internal walls 417, 427 of the housings 410, 420, and the angled transitions 414, 424 within both housings 410, 420 also help to direct the wireline 190 into position for cutting. When the wireline 190 is trapped by the blades 500 against the internal walls 417, 427, the teeth 515 grip the wireline 190, and the work string 180 is raised up with an adequate force to close the blades 500 even more to cut the wireline 190 with the teeth 515. Therefore, using the one-trip cutting system 250 comprising a coiled tubing cutter 300 and a wireline cutter 400, the coiled tubing 150 and the wireline 190 will be cut in the same general vicinity and fairly simultaneously, all in one trip into the well 160.
As previously described, because the wireline cutter 400 is a modular system, the operator can include as many or as few modular housings 420 as necessary to provide the desired number of blades 500 to cut the wireline 190. Therefore, the operator could elect to have only one blade 500 provided in the primary housing 410, or ten blades 500 provided in the primary housing 410 connected to nine modular housings 420, for example. Also, as previously described, the circumferential alignment of the blades 500 can be staggered by using the system of set screw slots 418 and cavities 429 with the set screw bores 428 that allow two housings 410, 420 to be rotationally adjusted as necessary. Thus, the operator may set the blades 500 at different angles circumferentially so that regardless of the position of the wireline 190 within the housings 410, 420, the wireline 190 will be captured and cut by one or more of the blades 500 that extend along the axial length of the wireline cutter 400. For example, if four blades 500 are provided, they could be positioned 90° apart from one another circumferentially.
In other operations, the wireline 190 may not be stuck, and the wireline cutter 400 may be used simply for retrieval purposes. For example, if the wireline 190 is very thick as compared to the wire size that the blades 500 are designed to cut, the blades 500 will tend to grip the wireline 190 without cutting it so that the wireline 190 may be pulled from the well 160. Whether or not the blades 500 will cut the wireline 190 depends upon the size of the wire and the pulling force applied to the work string 180.
In still other operations, a wireline 190 or other umbilical not associated with a coiled tubing string 150 may be stuck within a well 160. As one of ordinary skill in the art will readily appreciate, the wireline cutter 400 shown in
The foregoing descriptions of specific embodiments of the wireline cutter 400, the one-trip cutting system 250, and the methods for cutting a wireline 190 or other umbilical have been presented for purposes of illustration and description and are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously many other modifications and variations are possible. In particular, the specific type and quantity of components that make up the wireline cutter 400 could be varied. For example, a different number of modular housings 420 with blades 500 disposed therein may be provided, including no modular housings 420. Further, the blades 500 may comprise a different design than the embodiments shown herein. In addition, the wireline cutter 400 may be used to cut other umbilicals besides a wireline 190.
While various embodiments of the wireline cutter 400 and the one-trip cutting system 250 have been shown and described herein, modifications may be made by one skilled in the art without departing from the spirit and the teachings of the invention. The embodiments described are exemplary only, and are not intended to be limiting. Many variations, combinations, and modifications of the device and methods disclosed herein are possible and are within the scope of the invention. Accordingly, the scope of protection is not limited by the description set out above, but is defined by the claims which follow, that scope including all equivalents of the subject matter of the claims.
