Completion method with telescoping perforation and fracturing tool

[0001] Not Applicable

[0002] Not Applicable

[0003] 1. Field of the Invention

[0004] The present invention is in the field of apparatus and methods used in fracturing an underground formation in an oil or gas well, and producing hydrocarbons from the well or injecting fluids into the well.

[0005] 2. Background Art

[0006] In the drilling and completion of oil and gas wells, it is common to position a liner in the well bore, to perforate the liner at a desired depth, to fracture the formation at that depth, and to provide for the sand free production of hydrocarbons from the well or the injection of fluids into the well. These operations are typically performed in several steps, requiring multiple trips into and out of the well bore with the work string. Since rig time is expensive, it would be helpful to be able to perform all of these operations with a single tool, and on a single trip into the well bore.

[0007] The present invention provides a tool and method for perforating a well bore liner, fracturing a formation, and producing or injecting fluids, all in a single trip. The apparatus includes a tubular tool body having a plurality of radially outwardly telescoping tubular elements, with a mechanical means for selectively controlling the hydrostatic fracturing of the formation through one or more of the telescoping elements and for selectively controlling the sand-free injection or production of fluids through one or more of the telescoping elements. The mechanical control device can be either one or more shifting sleeves, or one or more check valves.

[0008] One embodiment of the apparatus has a built-in sand control medium in one or more of the telescoping elements, to allow for injection or production, and a check valve in one or more of the telescoping elements, to allow for one way flow to hydrostatically fracture the formation without allowing sand intrusion after fracturing.

[0009] Another embodiment of the apparatus has a sleeve which shifts between a fracturing position and an injection/production position, to convert the tool between these two types of operation. The sleeve can shift longitudinally or it can rotate.

[0010] The sleeve can be a solid walled sleeve which shifts to selectively open and close the different telescoping elements, with some telescoping elements having a built-in sand control medium (which may be referred to in this case as “sand control elements”) and other telescoping elements having no built-in sand control medium (which may be referred to in this case as “fracturing elements”).

[0011] Or, the sleeve itself can be a sand control medium, such as a screen, which shifts to selectively convert the telescoping elements between the fracturing mode and the injection/production mode. In this embodiment, none of the telescoping elements would have a built-in sand control medium.

[0012] Or, the sleeve can have ports which are shifted to selectively open and close the different telescoping elements, with some telescoping elements having a built-in sand control medium (which may be referred to in this case as “sand control elements”) and other telescoping elements having no built-in sand control medium (which may be referred to in this case as “fracturing elements”). In this embodiment, the sleeve shifts to selectively place the ports over either the “sand control elements” or the “fracturing elements”.

[0013] Or, the sleeve can have ports, some of which contain a sand control medium (which may be referred to in this case as “sand control ports”) and some of which do not (which may be referred to in this case as “fracturing ports”). In this embodiment, none of the telescoping elements would have a built-in sand control medium, and the sleeve shifts to selectively place either the “sand control ports” or the “fracturing ports” over the telescoping elements.

[0014] The novel features of this invention, as well as the invention itself, will be best understood from the attached drawings, taken along with the following description, in which similar reference characters refer to similar parts, and in which:

[0022] As shown in FIG. 1, in one embodiment, the tool 10 of the present invention has a plurality of telescoping elements 12, 14. All of these telescoping elements 12, 14 are shown retracted radially into the body of the tool 10, in the run-in position. A first group of these elements 12 have no sand control medium therein, while a second group of these elements 14 have a sand control medium incorporated therein. The sand control medium prevents intrusion of sand or other particulate matter from the formation into the tool body. FIG. 2 shows the telescoping elements 12, 14 extended radially outwardly from the body of the tool 10 to contact the underground formation, such as by the application of hydraulic pressure from the fluid flowing through the tool 10. If any of the elements 12, 14 fail to fully extend upon application of this hydraulic pressure, they can be mechanically extended by the passage of a tapered plug (not shown) through the body of the tool 10, as is known in the art. After extension of the telescoping elements 12, 14 to contact the formation, a proppant laden fluid is pumped through the tool 10, as is known in the art, to apply sufficient pressure to fracture the formation and to maintain the formation cracks open for the injection or production of fluids. This proppant laden fluid will pass through the fracturing elements 12, but it will not damage the sand control elements 14. After fracturing, a shifting sleeve 16 is shifted longitudinally, in a sliding fashion, as shown in FIG. 3, to cover the fracturing elements 12, while leaving the sand control elements 14 uncovered. Shifting of the sleeve 16 can be by means of any kind of shifting tool (not shown) known in the art. It can be seen that in this case, the fracturing elements 12 are arrayed in two fracturing zones 18, both above and below the desired production/injection zone where the sand control elements 14 are arrayed. When the upper and lower fracturing zones 18 are fractured, the formation cracks will propagate throughout the depth of the injection/production zone therebetween.

[0023] FIGS. 4 through 6 show a similar type of tool 10 to that shown in FIGS. 1 through 3, except that the fracturing zone 18 is only below the injection/production zone 20. This type of arrangement might be used where it is not desired to fracture a water bearing formation immediately above the injection/production zone 20.

[0024] FIGS. 7 through 9 show another embodiment of the tool 10 which has no shifting sleeve. This embodiment, however, has a different type of mechanical control device for controlling the fracturing and production/injection through the telescoping elements 12, 14. That is, while as before, each of the sand control elements 14 incorporates a built-in sand control medium, each of the fracturing elements 12 incorporates a check valve 22 therein. So, in this embodiment, once the tool 10 is at the desired depth, and the telescoping elements 12, 14 have been extended, the fracturing fluid passes through the check valves in the fracturing elements 12 into the formation. Thereafter, the hydrocarbon fluids can be produced from the formation through the sand control elements 14, or fluid can be injected into the formation through the sand control elements 14.

[0025] It can be seen that in FIGS. 7 through 9, the fracturing elements 12 alternate both above and below the sand control elements 14, instead of being grouped above or below as shown in two different types of arrangement in FIGS. 1 through 6. It should be understood, however, that any of these three types of arrangement could be achieved with either the shifting sleeve type of tool or the check valve type of tool.

[0026] Other embodiments of the apparatus 10 can also be used to achieve any of the three types of arrangement of the telescoping elements 12, 14 shown in FIGS. 1 through 9. First, a longitudinally sliding type of shifting sleeve 16 is shown in FIGS. 10 and 11. In this embodiment, the shifting sleeve 16 is a solid walled sleeve as before, but it can be positioned and adapted to shift in front of, as in FIG. 10, or away from, as in FIG. 11, a single row of fracturing elements 12, as well as the multiple row coverage shown in FIG. 3. It can be seen that the fracturing elements 12 have an open central bore for the passage of proppant laden fracturing fluid. The sand control elements 14 can have any type of built-in sand control medium therein, with examples of metallic beads and screen material being shown in the Figures. Whether or not the shifting sleeve 16 covers the sand control elements 14 when it uncovers the fracturing elements 12 is immaterial to the efficacy of the tool 10.

[0027] A second type of shifting sleeve 16 is shown in FIGS. 12 and 13. This longitudinally sliding shifting sleeve 16 is constructed principally of a sand control medium such as a screen. FIG. 12 shows the sleeve 16 positioned in front of the telescoping elements 12, for injection or production of fluid. FIG. 13 shows the sleeve 16 positioned away from the telescoping elements 12, for pumping of proppant laden fluid into the formation. In this embodiment, none of the telescoping elements has a built-in sand control medium.

[0028] A third type of shifting sleeve 16 is shown in FIGS. 14 and 15. This shifting sleeve 16 is a longitudinally shifting solid walled sleeve having a plurality of ports 24. The sleeve 16 shifts longitudinally to position the ports 24 either in front of or away from the fracturing elements 12. FIG. 14 shows the ports 24 of the sleeve 16 positioned away from the fracturing elements 12, for injection or production of fluid through the sand control elements 14. FIG. 15 shows the ports 24 of the sleeve 16 positioned in front of the fracturing elements 12, for pumping of proppant laden fluid into the formation. In this embodiment, the fracturing elements 12 have an open central bore for the passage of proppant laden fracturing fluid. The sand control elements 14 can have any type of built-in sand control medium therein. Here again, whether or not the shifting sleeve 16 covers the sand control elements 14 when it uncovers the fracturing elements 12 is immaterial to the efficacy of the tool 10.

[0029] A fourth type of shifting sleeve 16 is shown in FIGS. 16 and 17. This shifting sleeve 16 is a rotationally shifting solid walled sleeve having a plurality of ports 24, 26. A first plurality of the ports 26 (the sand control ports) have a sand control medium incorporated therein, while a second plurality of ports 24 (the fracturing ports) have no sand control medium therein. The sleeve 16 shifts rotationally to position either the fracturing ports 24 or the sand control ports 26 in front of the telescoping elements 12. FIG. 16 shows the fracturing ports 24 of the sleeve 16 positioned in front of the elements 12, for pumping of proppant laden fluid into the formation. FIG. 17 shows the sand control ports 26 of the sleeve 16 positioned in front of the telescoping elements 12, for injection or production of fluid through the elements 12. In this embodiment, all of the telescoping elements 12 have an open central bore; none of the telescoping elements has a built-in sand control medium.

[0030] It should be understood that a rotationally shifting type of sleeve, as shown in FIGS. 16 and 17, could be used with only open ports, as shown in FIGS. 14 and 15, with both fracturing elements 12 and sand control elements 14, without departing from the present invention. It should be further understood that a longitudinally shifting type of sleeve, as shown in FIGS. 14 and 15, could be used with both open ports and sand control ports, as shown in FIGS. 16 and 17, with only open telescoping elements 12, without departing from the present invention.

[0031] While the particular invention as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages hereinbefore stated, it is to be understood that this disclosure is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended other than as described in the appended claims.