In the drilling and completion industry, the formation of boreholes for the purpose of production or injection of fluid is common. Hydrocarbons such as oil and gas can be recovered from the subterranean formation using the boreholes. In producing hydrocarbons or the like from loosely or unconsolidated and/or fractured formations, it is not uncommon to produce large volumes of particulate material along with the formation fluids. As is well known in the art, these particulates routinely cause a variety of problems and must be controlled in order for production to be economical. One technique used for controlling the production of particulates (e.g., sand) from a well is one that is commonly known as “gravel-packing.”
In a typical gravel-packed completion, a screen is lowered into the wellbore on a work string and is positioned adjacent to the subterranean formation to be completed, e.g., a production formation. Particulate material, collectively referred to as “gravel,” and a carrier fluid is then pumped as a slurry down the work string where it exits through a “cross-over” into the well annulus formed between the screen and the well casing or open hole, as the case may be. The liquid in the slurry normally flows into the formation and/or through the screen itself, which, in turn, is sized to prevent flow of gravel therethrough. This results in the gravel being deposited or “screened out” in the well annulus where it collects to form a gravel pack around the screen. The gravel, in turn, is sized so that it forms a permeable mass that allows the flow of the produced fluids therethrough and into the screen while blocking the flow of the particulates produced with the production fluids.
One major problem that occurs in gravel-packing single zones, particularly where they are long or inclined, arises from the difficulty in distributing the gravel over the entire completion interval, i.e., completely packing the entire length of the well annulus around the screen. This poor distribution of gravel (i.e., incomplete packing of the interval) is often caused by the carrier fluid in the gravel slurry being lost into the more permeable portions of the formation, which, in turn, causes the gravel to form “sand bridges” in the annulus before all the gravel has been placed. Such bridges block further flow of slurry through the annulus, which prevents the placement of sufficient gravel below the bridge in top-to-bottom packing operations or above the bridge in bottom-to-top packing operations.
To address this specific problem, “alternate path” well strings have been developed which provide for distribution of gravel throughout the entire completion interval, even if sand bridges form before all the gravel has been placed. In these well screens, the alternate paths are formed by perforated shunts or bypass conduits and extend along the length of the screen and are in fluid communication with the gravel slurry as the slurry enters the well annulus around the screen. Such conduits may be placed on the outside of the screen with another shroud over the alternate paths to prevent them from being damaged during insertion or removal. If a sand bridge forms in the annulus, the slurry is still free to flow through the conduits and out into the annulus through the perforations in the conduits to complete the filling of the annulus above and/or below the sand bridge.
The art would be receptive to alternative and improved alternate path constructions and methods for a gravel packing operation.
A gravel pack system includes a first tubular having a longitudinal axis and a first wall permitting radial fluidic movement, a second tubular surrounding the first tubular, the second tubular having a second wall permitting radial fluidic movement, and an open channel forming an alternate flow path and configured to flow slurry along the flow path relative to the longitudinal axis of the first tubular during a gravel pack operation, at least one side of the channel formed by a portion of at least one of the first and second walls. Fluidic communication between the channel and the first tubular in a radial direction is at least substantially blocked during the gravel pack operation.
A method of operating downhole includes performing a gravel pack operation utilizing a channel as an alternate flow path for slurry; blocking movement of slurry fluid within the channel in an inwardly radial direction by an impermeable portion of the channel; at least partially degrading the impermeable portion of the channel to provide fluidic communication with a first tubular in an inwardly radial direction; and, producing production fluids through the channel and first tubular in the inwardly radial direction.
A gravel pack system includes an apertured outer shroud configured to surround a screen, the apertured outer shroud including a plurality of apertures, the apertured outer shroud further including at least one indent extending radially inwardly, the at least one indent forming a channel for an alternate flow path.
The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:
A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.
With reference now to
The channel 24 in the gravel pack system of
During the gravel pack operation, in order for slurry 16 to travel along the alternate flow path 32 without radially losing fluid from the slurry 16 through the tubular 18, the channel 24 may further include a fluidically impermeable layer 42 disposed between the tubular 18 and the alternate flow path 32. The layer 42 may, in one embodiment, be temporarily fluidically impermeable and include a degradable material 36 that may be substantially or entirely degradable so that production fluids may be allowed to pass from the channel 24 and radially into the tubular 18 and base pipe 14 during production. A degradable polymer material that is sufficiently resistant to erosion provides a suitable channel surface, though other degradable materials 36 could be used. In one embodiment, the degradable material 36 may cover the tubular 18 along substantially an entire length of the channel 24. For example, a polyvinyl alcohol degradable polymer may be formed in a film to cover substantially an entire area defined between the rods 30 of the channel 24. In another embodiment, the layer 42 may be fluid impermeable and non-degradable, and the degradable material 36 may be isolated as inserts 44 within the fluidically impermeable layer 42, such as when a non-degradable material is used as the fluidically impermeable layer, and optional sand control inserts 44 are initially plugged with degradable material 36 and provided at desired intervals along the channel 24 to cover the tubular 18. The degradable material 36 for the inserts may include, but is not limited to, a degradable polymer, or alternatively may include controlled electrolytic metallic (CEM) nanostructured material. Other degradable materials 36 suitable for maintaining fluid impermeability during a gravel packing operation and subsequent degradation before or during a production operation may also be employed. In yet another embodiment, the layer 42 may be fluid impermeable and non-degradable yet not be provided with degradable inserts. In still another embodiment, the layer 42 may be integral with the tubular 18 such as by providing a fluid impermeable section of the tubular 18 along the channel 24. In still yet another embodiment, the layer 42 may be fluid impermeable and non-degradable, but access to fluid permeable portions of the tubular 18 may be had through the openings 38 between the rods 30 upon degradation of the sections 34.
Also during the gravel pack operation, in order for slurry 16 to travel along the alternate flow path 32 without losing fluid from the slurry 16 through the outer tubular 20, the outer tubular 20 includes a fluid impermeable section 46 along substantially an entire length and width of the channel 24. Although not shown, the fluid impermeable section 46 may be interrupted by one or more emitters disposed along the length of the channel 24 to allow for the slurry 16 carried through the channel 24 to be selectively deposited within the annulus 48 between the gravel pack system 10 and the wall of the 12. The fluid impermeable section 46 may be obtained by simply not providing apertures within that section 46 of the outer tubular 20. Alternatively, the fluid impermeable section 46 may include apertures 22 which are filled or covered with degradable material 36. For example, the apertures 22 may be filled with a degradable material 36 such as the degradable inserts 44, or the area of the impermeable section 46 may be made fluid impermeable by applying a degradable impermeable layer 42 on the section 46 to form one side of the channel 24 for the alternate flow path 32. In such an embodiment, the fluid impermeable section 46 is fluid permeable during a production phase, thus increasing an overall production surface area for the system 10.
With additional reference to
With reference now to
The channels 224 of the gravel pack system 210 of
The embodiments of a gravel pack system 10, 210, 310 disclosed herein eliminate separate slurry delivery tubes completely as compared to conventional gravel pack systems having slurry tubes for alternate flow paths. By eliminating slurry delivery tubes and utilizing inner and/or outer tubulars of the gravel pack systems 10, 210, 310 as a wall or walls of the channels, an increase in cross-sectional area of the flow path 32 may be obtained, and cost benefits may be realized by eliminating the slurry tubes. Further, embodiments of the gravel pack system 10, 210, 310 reclaim production flow area otherwise occupied by the tubes. In lieu of slurry delivery tubes, in some embodiments, a channel is formed between an impermeable longitudinal section of the shroud and a corresponding longitudinal section of the tubular 18. To facilitate gravel packing operations in the channel during gravel pack operations, the screen section along the channel length and width is covered, coated or otherwise treated to prevent fluid flow through the screen. In some embodiments, this layer or other treatment will degrade after gravel packing, such as during production, to provide additional production flow area through the channel area, and at least periodic sections of the rods 30 may also be degradable to permit circumferential flow in the annulus between the shroud and the screen during production. Channel inserts 128 may alternatively be provided. A single conventional tube may still be desired to provide one or more suitable exit ports for each screen section. However, shroud openings along the channel alone may suffice. In other embodiments, channels are formed into the outer shroud during manufacture and used to assemble cartridge assemblies. Formed channels can be lined with a impermeable material for flow assurance during gravel packing operation and may further be dissolvable/degradable to increase production area during production. Also, helical flow channels can be formed during manufacture of the outer shroud of the cartridge assemblies.
Shroud design may need to be reinforced to support flow rate burst pressures; however, channel number and sizing can be adjusted to reduce this pressure considerably. In embodiments utilizing degradable material, when the material is reliably degradable, virtually the entire screen OD could be used for slurry delivery, reducing the burst pressures considerably. The embodiments of a gravel pack system 10, 210, 310 thus save cost and manufacturing requirements of slurry transport tubes while increasing production flow area through the tubular 18.
A gravel pack system includes a first tubular having a longitudinal axis and a first wall permitting radial fluidic movement, a second tubular surrounding the first tubular, the second tubular having a second wall permitting radial fluidic movement, and an open channel forming an alternate flow path and configured to flow slurry along the flow path relative to the longitudinal axis of the first tubular during a gravel pack operation, at least one side of the channel formed by a portion of at least one of the first and second walls. Fluidic communication between the channel and the first tubular in a radial direction is at least substantially blocked during the gravel pack operation.
The gravel pack system of embodiment 1, wherein the channel is formed between the first tubular and the second tubular.
The gravel pack system of embodiment 2, wherein the channel includes two circumferentially spaced rods extending longitudinally between the first and second tubulars.
The gravel pack system of embodiment 3, further comprising a degradable material disposed between the rods.
The gravel pack system of embodiment 3, wherein a portion of at least one of the rods includes a degradable material.
The gravel pack system of embodiment 2, wherein the channel includes a degradable polymer channel insert disposed between the first and second tubulars, the insert including first and second longitudinally extending walls and an intermediate section connecting the first and second longitudinally extending walls.
The gravel pack system of embodiment 2, wherein the second tubular includes a fluid impermeable section extending along substantially an entire length and width of the channel.
The gravel pack system of embodiment 1, wherein the channel is disposed on an outer surface of the second tubular.
The gravel pack system of embodiment 1, wherein the channel is an indent formed along a surface of the second tubular.
The gravel pack system of embodiment 9, wherein the indent extends helically about the longitudinal axis.
The gravel pack system of embodiment 10, wherein the second tubular is formed from a non-planar strip having edges offset from a main portion, and the strip is spiral welded along a helical line to join the edges and form the indent.
The gravel pack system of embodiment 9, wherein the indent extends substantially parallel to the longitudinal axis.
The gravel pack system of embodiment 9, wherein a cross-section of the indent extends radially inward towards the first tubular.
The gravel pack system of embodiment 9, further comprising a degradable material disposed within the indent.
The gravel pack system of embodiment 1, wherein at least a section of the channel is formed of a degradable material, and fluidic communication between the channel and the first tubular is at least substantially blocked in a radial direction in a non-degraded condition of the degradable material, and fluidic communication between the channel and the first tubular in a radial direction is permitted in a degraded condition of the degradable material.
The gravel pack system of embodiment 15, wherein the degradable material includes a polymeric material.
The gravel pack system of embodiment 15, wherein the degradable material includes a controlled electrolytic metallic nanostructured material.
A completion system including the gravel pack system of embodiment 1, the completion system further comprising a third tubular disposed within the first tubular, wherein the first tubular is a screen, the second tubular is a shroud, and the third tubular is a base pipe.
A method of operating downhole, the method comprising: performing a gravel pack operation utilizing the gravel pack system of embodiment 1 and delivering slurry through the channel.
A method of operating downhole, the method comprising: performing a gravel pack operation utilizing a channel as an alternate flow path for slurry; blocking movement of slurry fluid within the channel in an inwardly radial direction by an impermeable portion of the channel; at least partially degrading the impermeable portion of the channel to provide fluidic communication with a first tubular in an inwardly radial direction; and, producing production fluids through the channel and first tubular in the inwardly radial direction.
The method of embodiment 20, wherein at least partially degrading the impermeable portion of the channel includes at least partially degrading a degradable material disposed on the screen.
The method of embodiment 20, wherein at least partially degrading the impermeable portion of the channel includes at least partially degrading a degradable material disposed on a shroud surrounding the screen.
The method of embodiment 20, wherein at least partially degrading the impermeable portion of the channel includes at least partially degrading a degradable material of the channel during a production operation.
A gravel pack system includes an apertured outer shroud configured to surround a screen, the apertured outer shroud including a plurality of apertures, the apertured outer shroud further including at least one indent extending radially inwardly, the at least one indent forming a channel for an alternate flow path.
The gravel pack system of embodiment 24 wherein the at least one indent extends along a spiral weld of the outer shroud.
The gravel pack system of embodiment 24 further comprising the screen and an inner shroud, wherein the indent is formed on the outer shroud during a swaging process of the outer shroud, screen, and inner shroud to form a cartridge assembly.
The gravel pack system of embodiment 24, further comprising a degradable material disposed within the at least one indent.
The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Further, it should further be noted that the terms “first,” “second,” and the like herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The modifier “about” used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the particular quantity).
The teachings of the present disclosure may be used in a variety of well operations. These operations may involve using one or more treatment agents to treat a formation, the fluids resident in a formation, a wellbore, and/or equipment in the wellbore, such as production tubing. The treatment agents may be in the form of liquids, gases, solids, semi-solids, and mixtures thereof. Illustrative treatment agents include, but are not limited to, fracturing fluids, acids, steam, water, brine, anti-corrosion agents, cement, permeability modifiers, drilling muds, emulsifiers, demulsifiers, tracers, flow improvers etc. Illustrative well operations include, but are not limited to, hydraulic fracturing, stimulation, tracer injection, cleaning, acidizing, steam injection, water flooding, cementing, etc.
While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited.