CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application is based on and claims priority to U.S. Provisional

Application Serial No. 62/686,634, filed June 18, 2018, which is incorporated herein by reference in its entirety.

BACKGROUND

[0002] Pack efficiency directly affects the productive life of an open hole well.

Voids left by incomplete packs expose screens to plugging and erosion, leading to early completion failure. The OptiPac Alternate Path gravel-packing system for open hole completions employs screens and shunt tubes in an integrated system to provide a complete gravel pack, while preventing premature screenout, erosion, hardware damage, and completion failure.

[0003] In the OptiPac Alternate Path system, shunt tubes are installed along the screens, each with a series of evenly placed nozzles. When a gravel bridge forms, the slurry naturally diverts into the shunts. When the slurry encounters a nozzle facing a void in the open hole, it flows out to fill all empty spaces in the unpacked annulus. This process continues until the interval is fully packed.

[0004] Open hole Alternate Path gravel packs are rapidly increasing in length from typically l000-2000ft to in excesses of 4000ft and up to 8000ft, whereby such new lengths are commonly referred to as extended reach wells. Accordingly, there is a need for complete gravel packing with respect to these greater distances. SUMMARY

[0005] According to one or more embodiments of the present disclosure, a method includes transporting a gravel pack slurry in a shunt tube system that includes at least one transport tube and at least one packing tube, wherein the gravel pack slurry includes a carrier fluid, and proppant or gravel; using the gravel pack slurry to pack gravel into the at least one packing tube of the shunt tube system; and restricting fluid loss through the at least one packing tube.

[0006] However, many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Certain embodiments of the disclosure will hereafter be described with reference to the accompanying drawings, wherein like reference numerals and/or labels denote like elements. It should be understood, however, that the accompanying figures illustrate the various implementations described herein and are not meant to limit the scope of various technologies described herein, and:

[0008] FIG. 1 shows an example of a 2x2 OptiPac System with a manifold according to one or more embodiments of the present disclosure;

[0009] FIG. 2 shows an example of a 2x2 OptiPac System with a manifold according to one or more embodiments of the present disclosure;

[0010] FIG. 3 shows an example of a 2x2 OptiPac System with chemical-induced packing tube shut-off, according to one or more embodiments of the disclosure; [0011] FIG. 4 shows an example of a 2x2 OptiPac System with chemical-induced packing tube shut-off, according to one or more embodiments of the disclosure;

[0012] FIG. 5A shows an example of a 2x2 OptiPac System with guillotine activation for packing tube shut-off, according to one or more embodiments of the present disclosure; and

[0013] FIG. 5B shows an example of guillotine activation for packing tube shut- off, according to one or more embodiments of the present disclosure;

[0014] FIG. 5C shows an example of guillotine activation for packing tube shut- off, according to one or more embodiments of the present disclosure;

[0015] FIG. 6 shows an example of a 2x2 OptiPac System with guillotine activation for packing tube shut-off, according to one or more embodiments of the present disclosure.

PET ATT, ED DESCRIPTION

[0016] In the following description, numerous details are set forth to provide an understanding of some embodiments of the present disclosure. However, it will be understood by those of ordinary skill in the art that the system and/or methodology may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.

[0017] To enable an OptiPac Alternate Path System to accommodate the greater distances required for extended reach applications, it is imperative for the gravel pack slurry to retain sufficient carrier fluid. That is, the slurry must maintain a sufficiently low proppant concentration for flow within the transport tube thus carrying the proppant to the toe. To reach such distances, the OptiPac shunt system will reach pressures up to 9,000 psi which further increases the dehydration potential. As shown in FIG. 1, the location on each OptiPac screen joint 10 where fluid losses take place is in the manifold 12 where the slurry crosses over from the transport tube 14 into the packing tube 16.

[0018] Referring now to FIG. 2 by way of example, when an OptiPac screen joint

10 is gravel packed, the gravel 18 is also packed within the packing tube 16. The packed gravel 18 within the packing tube 16 is key to the resistance of carrier fluid loss from the transport system to the wellbore because the tightly packed gravel 18 provides a signficant flow resistance. As shown in FIG. 2, for example, the associated pressure of the packed gravel 18 may be as high as 9,000 psi up to the first nozzle 26 of the packing tube 16. However, at the high system pressures needed to achieve extended reaches, the losses of carrier fluid may become too significant to enable slurry to reach the toe. One or more embodiments of the present disclosure provide methods to greatly inhibit or shut off losses of carrier fluid through the packing tubes.

[0019] More specifically, one or more embodiments of the present disclosure uses pressure within the transport tube of the OptiPac system during the gravel packing process to activate a leak-off inhibitor within the packing tube. Use of pressure within the transport tube as an“activator” is the same triggering method used to activate inflow control devices (ICDs) within the OptiPac System as described in International Patent Application Publication No. WO2018/170345, which is incorporated by reference herein in its entirety.

[0020] One or more embodiments of the present disclosure generally relate to methods for significantly restricting or completely shutting off leak-off through the packing tube. In a chemical method according to one or more embodiments of the present disclosure, solidification of a polymer carrier fluid is chemically-induced within the packing tube, which prevents the ability of the polymer to flow. For example, Xanthan is a polymer that may be used in gravel packing with polymer carrier fluids. According to one or more embodiments of the present disclosure, the Xanthan polymer crosslinks into a solid gelled mass when it contacts a“multivalent,” i.e., not monovalent, metal. In one or more embodiments of the present disclosure, the“multivalent” metal may include aluminum, magnesium, an aluminum alloy, or a magnesium alloy, for example. One or more embodiments of the present disclosure capitalizes on this crosslinking phenomenon of the polymer.

[0021] In the chemical method according to one or more embodiments of the present disclosure, the pressure buildup within the transport tube is used to inject a solution of a multivalent metal into the ID of the already-packed packing tube. Once injected into the packing tube, the multivalent metal solution reacts with the Xanthan polymer, for example, within the gravel pack pores creating a solid gel. This gel prevents flow thereby shutting off fluid losses through the packing tube.

[0022] Embodiments of the present disclosure are not limited to a crosslinked solid gelled mass or hardened bridge within the packing tube. In other embodiments, fines that plug up the pores within the gravel pack inside the packing tube may be injected to achieve stoppage of flow within the packing tube. In some embodiments, a two-part hardener (similar to JB weld or other epoxy product) may be individually injected into the packing tube, and upon mixing, the two parts may harden to form a bridge that ceases flow within the packing tube.

[0023] Referring generally to FIG. 3, an example of an OptiPac System with chemical-induced packing tube shut-off is illustrated, according to one or more embodiments of the present disclosure. Specifically, FIG. 3 shows a syringe-like cartridge 20 containing an injection solution 22, which may be a cross-link inducing fluid in accordance with one or more embodiments of the present disclosure. As shown, the syringe-like cartridge 20 may be connected into the transport tube 14 ID with a control line 24 and directed into the packing tube 16 above the first nozzle 26 A syringe- activating burst disc 28 is placed in the control line 24 either between the syringe 20 and transport tube 14 or between the syringe 20 and packing tube 16 The burst disc 28 activating pressure shall be set at a pressure greater than that needed to ensure a complete gravel pack for that OptiPac screen joint 10. For example, the burst disc 28 may be set to activate between 500 - 3000 psi in accordance with one or more embodiments of the present disclosure.

[0024] Referring generally to FIG. 4, an example of an OptiPac System with chemical-induced packing tube shut-off is illustrated, according to one or more embodiments of the present disclosure. Specifically, FIG. 4 shows the burst disc of FIG. 3 activated. FIG. 4 further shows that the piston within the syringe 20 has“injected” the cross-link inducing fluid 22 into the packing tube 12 above the first nozzle 26 to initiate the gelling of the Xanthan polymer. According to one or more embodiments of the present disclosure, such gelling of the Xanthan polymer above the first nozzle 26 of the packing tube 12 causes fluid migration within the packing tube 12 to be substantially reduced or to cease altogether.

[0025] Further, in a mechanical method according to one or more embodiments of the present disclosure, a guillotine-like plate is inserted across the ID of the packing tube to drastically reduce the flow area of the packing tube, which restricts the leak-off flow area. In one or more embodiments of the present disclosure, the mechanical method is independent of carrier fluid used for the gravel pack process. In other words, the mechanical method is applicable to polymer-based and visco-elastic surfactant (VES) fluids.

[0026] In the mechanical method according to one or more embodiments of the present disclosure, using the transport tube pressure during the gravel pack process, a guillotine-like plate is activated and inserted into the packing tube flow path. The plate “slices” into the packed gravel to reduce or close-off the packing tube flow area. That is, upon activation, the guillotine-like plate is inserted across an interior of the packing tube, thereby reducing an internal flow area of the packing tube.

[0027] Referring generally to FIG. 5A, an example of an OptiPac System with guillotine activation for packing tube shut-off is illustrated, according to one or more embodiments of the present disclosure. Specifically, FIG. 5A shows a burst disc 28 connected to the guillotine 30, and the guillotine 30 mounted to the packing tube 16 just above the first nozzle 26 (between the first nozzle 26 and the manifold) with a control line 24 ported to the transport tube 14. The packing tube 16 has an open slit in its wall within which the guillotine 30 plate is positioned. According to one or more embodiments of the present disclosure, the guillotine 30 may be activated by applying the transport tube 14 pressure against the piston 32 (FIG. 5B). Upon activation, the guillotine 30 may be inserted into the packed gravel 18 of the packing tube 16 flow path to reduce or close-off the packing tube 16 flow area. In one or more embodiments of the present disclosure, the guillotine 30 may be spring-loaded by coupling the guillotine 30 with a loaded spring 34 (FIG. 5C). The spring-loaded 34 guillotine 30 may be activated by using the transport tube pressure to shear a retaining pin 36 to release the guillotine. Upon activation/release, the spring-loaded 34 guillotine 30 may be inserted into the packed gravel 18 of the packing tube 16 flow path to reduce or close-off the packing tube 16 flow area.

[0028] For example, as shown in FIG. 6, the burst disc 28 shown in FIG. 5A is activated, and the guillotine 30 is shifted across the packing tube opening 38 just above the first nozzle 26. As shown, the guillotine-like plate 30 now restricts the area available for flow thus reducing the leak-off capacity of the packing tube 16.

[0029] Although a few embodiments of the disclosure have been described in detail above, those of ordinary skill in the art will readily appreciate that many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.