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Patent Searching and Data


Title:
DEVICE AND METHOD FOR SAND CONTROL WITH ENHANCED SAND BRIDGING
Document Type and Number:
WIPO Patent Application WO/2017/130102
Kind Code:
A1
Abstract:
Embodiments described herein provide well screens and methods that promote sand arching and reduced erosion. One embodiment is a well screen which generally comprises a wire which is spirally wound to form a cylinder with a slot between each role of the wire. The outer surface of the wire comprises one or more indented features shaped to promote sand bridging or reduced erosion. The indented feature may comprise a longitudinal channel.

Inventors:
VAN PETEGEM RONALD (US)
BANERJEE SUDIPTYA (US)
Application Number:
PCT/IB2017/050366
Publication Date:
August 03, 2017
Filing Date:
January 24, 2017
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
PACKERS PLUS ENERGY SERV INC (CA)
International Classes:
E21B43/02; E21B43/08
Foreign References:
US5095990A1992-03-17
US3709293A1973-01-09
Download PDF:
Claims:
WHAT IS CLAIMED IS:

1 . A sand control assembly comprising:

a support; and

a wrapped wire supported by the support and wrapped to create a wire-wrapped screen having a slot of selected size between adjacent wrappings, the wrapped wire comprising a radially outer surface defining an indented feature selected to enhance formation of a sand bridge across the slot.

2. The sand control assembly of Claim 1 , wherein the indented feature comprises a longitudinal channel.

3. The sand control assembly of Claim 2, wherein the longitudinal channel comprises channel sidewalls sloped away from the slot and having a maximum slope angle between 5- 80 degrees.

4. The sand control assembly of any of Claim 2 or Claim 3, wherein the longitudinal channel comprises channel sidewalls having a slope angle approximately equal to an angle of repose of selected particulates in a well.

5. The sand control assembly of any of Claims 1 - 4, wherein the outer surface of the wire is shaped to form a sinusoidal profile.

6. The sand control assembly of any of Claims 1 -4, wherein the outer surface of the wire is shaped to form a serrated profile.

7. The sand control assembly of Claim 2, wherein the longitudinal channel is a square channel.

8. The sand control assembly of any of Claims 1 -7, wherein the indented feature is selected to promote formation of sand arches across the slot.

9. The sand control assembly of any of Claims 1 -8, further comprising a base pipe, wherein the support is coupled to the base pipe.

10. The sand control assembly of Claim 9, wherein the support comprises a rib of the base pipe.

1 1 . The sand control assembly of Claim 9, wherein the support is coupled to the base pipe by a mounting ring.

12. The sand control assembly of any of Claims 9-1 1 , wherein the base pipe is a non- perforated pipe.

13. The sand control assembly of any of Claims 9-1 1 , wherein the base pipe is a perforated base pipe.

14. A slotted liner comprising a tubular body defining at least one slot extending through the tubular body and a set of indented features disposed on an outer surface of the tubular body adjacent to the slot, the indented features selected to enhance sand bridging across the slot.

15. The slotted liner of Claim 14, wherein the indented features comprise channels.

16. The slotted liner of Claim 15, wherein the channels comprise channel sidewalls sloped away from the slot and having a maximum slope angle between 5°-80°.

17. The slotted liner of any of Claims 15-16, wherein the channels comprise channel sidewalls having a slope angle approximately equal to an angle of repose of selected particulates in a well.

18. The slotted liner of any of Claims 14-17, wherein the outer surface of the slotted liner is shaped to form a sinusoidal profile.

19. The slotted liner of any of Claims 14-17, wherein the outer surface of the slotted liner is shaped to form a serrated profile.

20. The slotted liner of any of Claims 14-19, wherein the indented features are selected to promote formation of sand arches across the slot.

Description:
DEVICE AND METHOD FOR SAND CONTROL WITH

ENHANCED SAND BRIDGING

RELATED APPLICATIONS

[0001 ] This application claims the benefit of priority to United States Provisional Application No.

62/286,679, entitled "Device and Method for Sand Control With Enhanced Sand Bridging," filed January 25, 2016, which is hereby fully incorporated by reference herein for all purposes.

TECHNICAL FIELD

[0002] Embodiments described herein relate to well screen devices and methods for removing particulates from hydrocarbons produced from a formation. More particularly, embodiments described herein relate to sand screens shaped to induce the formation of stable sand arches and prevent erosion.

BACKGROUND

[0003] Since its inception, the oil industry has faced the perennial problem of sand production (or

"sanding"). When sanding occurs, particulates can contaminate the production fluid, erode production equipment, block flow passages and result in other deleterious consequences. Consequently, many well operators employ sand control techniques to reduce sanding. Sand control techniques often rely on subsurface sand control devices to prevent formation sand from entering the well. These devices typically include a perforated base pipe and a screen disposed around the circumference of the pipe. The screen serves to screen out solids before fluid enters the production tubing through the base pipe. In some installations, the screen is used in conjunction with a surrounding layer of aggregate (a "gravel pack") to prevent production sand from entering the well. It is noted that in some cases the base pipe is not perforated, in which case the fluid travels between the inner surface or the wire and the outer surface of the base pipe through a flow control device into the base pipe.

[0004] One type of screen commonly used in sand control devices is a wire-wrapped screen. In wire-wrapped devices, a wire is wrapped around the perforated base pipe to form a slot through which fluid can pass to reach the pipe. The wires used to make conventional wire- wrapped screens are either circular or— more typically— keystone, house, or triangular shaped, with a flat outer surface and short radiuses on the edges. FIG. 1 illustrates common wire profiles used in the industry.

[0005] FIG. 2 illustrates a portion of a wire-wrapped screen using a conventional keystone-shaped wire 50. With reference to FIG. 2, the width of slots 52 is usually selected so that that the larger particles screened out can potentially form a sand bridge across the slot. While the particles may temporarily form sand bridges 54 across the slot, these sand bridges are relatively flat, unstable and prone to collapsing.

[0006] Over a period of time, the sand bridge formed on the flat wire wrapped screen can break down resulting in flow of sand along with the production fluids into the slots created by the wire wrapped screen. As a result, one or more particles may get lodged into the slots and then accumulate in the sand control device thereby choking the sand control device. Consequently, traditional wire-wrapped sand screens are prone to plugging or otherwise impeding flow over time. Besides lodging of particles within the slots, other mechanisms or combination of mechanisms including but not limited to plugging of the sand bridge are possible.

[0007] Moreover, many formations, even if they are not producing significant amounts of sand, may produce small particles, including "fines" (particles that are typically smaller than 44 micron in diameter). These small and fine particles can typically pass through the screen. As they do so, the particles may erode the wire. In some cases particles impacting the screen at certain velocities can also cause erosion.

SUMMARY

[0008] Embodiments described herein provide well screens and methods that promote sand arching and reduced erosion. In accordance with one embodiment, a sand control assembly may comprise a support and a wrapped wire supported by the support. The wire is wrapped to create a wire-wrapped screen having a slot of selected size between adjacent wrappings. The wrapped wire can comprise a radially outer surface defining an indented feature selected to enhance the formation of a sand bridge across the slot. More particularly, in some embodiments, the indented feature is adjacent to the slot and selected to promote formation of sand arches across the slot.

[0009] The indented feature may comprise a longitudinal channel with a curved, square, chevron or other profile. According to one embodiment, the longitudinal channel comprises channel sidewalls sloped away from the slot and having a maximum slope angle between 5-80 degrees. In cases, the slope angle may be selected to be approximately equal to an angle of repose of selected particulates in a well.

[0010] Another embodiment may comprise a slotted liner comprising a tubular body defining at least one slot extending through the tubular body and a set of indented features disposed on an outer surface of the tubular body adjacent to the slot, the indented features selected to enhance sand bridging across the slot. The indented features may comprise, for example, channels. The indented features comprise sidewalls sloped away from the slot and having a maximum slope angle, in some embodiments, of between 5°-80 °. In some cases, the channels comprise channel sidewalls having a slope angle selected to promote sand arches over the slot.

[001 1 ] Embodiments described herein can provide advantages over conventional wire-wrapped screens. As one advantage, embodiments of screens can be formed that reduce impingement based erosion by reducing conversion and velocity acceleration towards the slot or opening in the screen.

[0012] As another advantage, embodiments of screens described herein can promote sand control earlier in the life of a well by promoting earlier formation of sand bridges.

[0013] As yet another advantage, embodiments of screens described herein can provide for increased production for the same filtration compared to conventional wire-wrapped screens while also extending the life of the screen.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings accompanying and forming part of this specification are included to depict certain aspects of the invention. A clearer impression of the invention, and of the components and operation of systems provided with the invention, will become more readily apparent by referring to the exemplary, and therefore non-limiting, embodiments illustrated in the drawings, wherein identical reference numerals designate the same components. Note that the features illustrated in the drawings are not necessarily drawn to scale.

[0015] FIGURE 1 illustrates the profiles of conventional wires used to form wire-wrapped screens.

[0016] FIGURE 2 is a diagrammatic representation of a conventional wire-wrapped screen.

[0017] FIGURE 3 is a diagrammatic representation of one embodiment of a well system. [0018] FIGURE 4A, FIGURE 4B and FIGURE 4C are views of one embodiment of a well screen assembly.

[0019] FIGURES 5A, 5B and 5C are diagrammatic representations of one embodiment of a wire that can be used to form a screen with enhanced sand bridging.

[0020] FIGURE 6A illustrates flow through a conventional screen.

[0021 ] FIGURE 6B illustrates flow through a screen with enhanced sand bridging.

[0022] FIGURE 7 is a diagrammatic representation of example embodiments of wire profiles.

[0023] FIGURE 8 is a diagrammatic representation of example hybrid-keystone wire profiles.

[0024] FIGURE 9A, FIGURE 9B, FIGURE 9C and FIGURE 9D are diagrammatic representations of views of one embodiment of a well screen assembly.

[0025] FIGURE 10A is a diagrammatic representation of a slotted liner and FIGURE 10B is a diagrammatic representation of a portion of the slotted liner.

[0026] FIGURE 1 1 A, FIGURE 1 1 B and FIGURE 1 1 C illustrate test data for a constant draw down test of one embodiment of a u-wire screen FIGURE 1 1 D illustrates a profile of one embodiment of a wire with enhanced sand bridging.

[0027] FIGURE 12 illustrates test data for a constant rate test of one embodiment of a u-wire screen.

DETAILED DESCRIPTION

[0028] This disclosure and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known starting materials, processing techniques, components and equipment are omitted so as not to unnecessarily obscure the disclosure in detail. Skilled artisans should understand, however, that the detailed description and the specific examples, while disclosing preferred embodiments, are given by way of illustration only and not by way of limitation. Various substitutions, modifications, additions or rearrangements within the scope of the underlying inventive concept(s) will become apparent to those skilled in the art after reading this disclosure.

[0029] Embodiments described herein relate to sand control devices and methods for removing sand from hydrocarbons produced from a formation. More particularly, embodiments described herein provide a sand screen shaped to induce the formation of stable sand arches. According to one embodiment, a sand control device comprises a wire-wrapped screen disposed about a perforated liner. The wire forms a slot between adjacent roles of the wire. The radially outer surface of the wire has an indented feature(s) shaped to promote the formation of sand bridges and, more particularly, in some embodiments, sand arches. In one embodiment, the indented feature comprises a longitudinal channel shaped to promote the formation of stable sand arches.

[0030] The wire-wrapped screen may be wrapped around an inflow control device (ICD). The wire wrapped screen may be formed by forming loops of wire around a perforated liner in a manner that a slot is formed between the loops to provide a flow channel. The width of the slot is such that it prevents large sized sand particles from entering into the sand control device. An outwardly facing surface of the wire has a depressed profile (as opposed to flat shaped outer radial surface of conventional wires) so that, in some embodiments, the outer surface of the screen formed by wire loops has a sinusoidal or serrated profile. The surface profile is configured to reduce break down of sand bridges that form on the screen.

[0031 ] In accordance with one embodiment, the outer surface of the wire-wrapped screen is shaped to promote earlier formation of sand bridges than conventional wires, providing sand control earlier in the life of the well. Furthermore, the wire may be shaped to control where natural compaction occurs. By providing a shape that promotes more stable bridges and managing where natural compaction happens, embodiments described herein can provide for increased production for the same filtration while also extending the life of the screen. [0032] FIG. 3 illustrates an example well system 60 comprising a production string 62 including a plurality of well screen assemblies 75. The well system 60 is shown as being a horizontal well, having a wellbore that deviates to horizontal. A production string 62 extends from wellhead, through the wellbore 64 and into the subterranean zone of interest. A portion of wellbore 64 may be cased while another portion can be completed open hole. In some instances, the annulus between the production string 62 and the open hole portion of the wellbore 64 may be packed with sand packing 66. In other embodiments, packing is not used.

[0033] The production string 62 operates in producing fluids (e.g., oil, gas, and/or other fluids) from the subterranean zone to the surface and can include packers, production ports and other tools. In particular production string 62 includes one or more well screen assemblies 75 (two shown). The well screen assemblies 75 and packing 66 allow communication of fluids between the subterranean zone and production string 62. The packing 66, if provided, provides a first stage of filtration against passage of particulate and larger fragments of the formation to the production string 62. The well screen assemblies 75 provide a second stage of filtration, and are configured to filter against passage of particulate of a specified size and larger into the production string 62.

[0034] Although shown in the context of a horizontal well system 60, well screen assemblies 75 can be provided in other well configurations, including vertical well systems having vertical or substantially vertical wellbore, multi-lateral well systems having multiple wellbores deviating from a common wellbore and/or other well systems. Also, although described in a production context, well screen assemblies 75 can be used in other contexts, including injection, well treatment and/or other applications.

[0035] Well screen assemblies may have a variety of configurations. FIG. 4A, FIG. 4B and FIG. 4C

(collectively FIG. 4) illustrate an embodiment of a well screen assembly 80, which can be an example of well screen assembly 75. Another embodiment of a well screen assembly 500, which can be another example of well screen assembly 75, is illustrated in FIG. 9A, FIG. 9B, FIG. 9C and FIG. 9D (collectively FIG. 9).

[0036] Referring to FIG. 4, well screen assembly 80 comprises a wire-wrapped screen 90 disposed about a base pipe 82, which may be a perforated base pipe as illustrated in FIG. 4B or an unperforated base pipe. Screen 90 can screen out particulates prior to production fluid flowing into pipe 82 through apertures 84 or otherwise flowing into the base pipe. Screen 90 comprises a wire or wires 100 wound around longitudinal supports 94 that space the wire 100 from base pipe 82. Wraps of the wire 100 cross the longitudinal supports 94 to form a tubular grid. Although shown with a plurality of substantially parallel longitudinal supports 94 oriented along the length of the screen 90, the supports 94 can be differently arranged. For example, in some instances, supports 94 can be substantially helical at a lesser pitch than the wrapping of the outer wire 100. In the example of FIG. 4A, the perimeter of wire-wrapped screen 90 exhibits a substantially circular geometry, but could be other shapes (e.g., polygonal and/or other shapes). As discussed below, wire 100 can be configured to promote stable sand arch formation and reduce erosion.

[0037] Wire wrapped screen 90 may be coupled to base pipe 82 in a variety of manners. According to one embodiment, for example, wire wrapped screen 90 may be coupled to base pipe 82 using a direct wrapping process. With direct wrapping, supports 94 are placed on base pipe 82 and wire 100 is wrapped directly over supports 94. Wire 100 may be bonded (e.g., welded, brazed, and/or otherwise bonded) or otherwise coupled to supports 94 at intersection points. In particular, a bonding method that requires heat (e.g., welding, brazing) can be used to couple wire 100 to supports 94. When wire 100 cools, the diameter of screen 90 will shrink, creating a friction fit between supports 94 and the base pipe 82. In another embodiment, supports 94 may be integral with or bonded to base pipe 82 and wire 100 can be bonded or otherwise coupled to supports 94.

[0038] In another embodiment, wire wrapped screen 90 can be formed as a slip-on screen. The end wraps of wire 100 and the ends of supports 94 can be bonded or otherwise coupled to mounting rings and the mounting rings can be bonded or otherwise coupled to the outer surface of base pipe 82. An example of a slip-on screen is illustrated in FIG. 9, discussed below.

[0039] FIGS. 5A-5C (referred to generally as FIG. 5) are diagrammatic representations of one embodiment of a portion of wire-wrapped screen 90 with FIG. 5C illustrating a cross-section of wire-wrapped screen 90 with accumulated sand.

[0040] FIG. 5A illustrates a profile of wire 100 (i.e., the cross-section orthogonal to the wire's longitudinal axis 101 ). In the embodiment illustrated, wire 100 has a height 122 and a width 120 and comprises an inner side 104, outer side 106 (also referred to as top) and side flanks 108 extending between the inner side and outer side. An inner surface 1 1 1 may form a flat, radiused or otherwise shaped nose that extends between side flanks 108. An outer surface 1 12 extends laterally between corners 107 with opposite side flanks 108. The corners 107 may be sharp corners, rounds, chamfers or have other desired profiles. [0041 ] Wire 100 is wrapped to form a slot 140 between adjacent wrappings (e.g., roles 102a and 102b) of wire 100. The slot width can be selected based, for example, on the particle size distribution of sand in the formation in which wire-wrapped screen 90 will be used and whether the sand is well sorted or poorly sorted. Formation sand sampling techniques and sieve analysis techniques can be used to determine the grain diameter for cumulative percentage weight, such as d 5 , di 0 , d 40 , d 50 , d 90 , d 95 , as is known in the art. The Society of Petroleum Engineers has published a number of methods for selecting a slot width for conventional wire wrapped screens based on grain diameters using, for example, the Sorting Coefficient (S c ) (di 0 /d 4 o) , Uniformity Coefficient (U c ) (d 4 o/d 9 o) or other parameters. Some conventional methods of selecting slot width include, but are not limited to: i) slot width: 1 -2 * d 10 ; ii) slot width: ~ 6.5 * d 50 ; ii) slot width: If U c <2 use d 50 , If U c ~2 use d 40 , If U c > 2 use d 30 ; iii) slot width: If U c <3 use d 10 , If U c > 5 use d 40 , If U c > 10 use d 70 ; iv) slot width: equal to d 5 or di 0 .

[0042] According to conventional slot width sizing techniques, the slot width will typically be .006- .020 inches. Regardless of how the slot size is selected, however, embodiments described herein can be configured to induce more stable bridges than traditional wire-wrapped screens of the same slot size. Moreover, according to embodiments described herein, the slot size can be increased to allow the slot to be wider than in prior wire-wrapped devices for the same size particle control, thereby increasing not only longevity, but also production.

[0043] The outer surface 1 12 of wire 100 is inwardly radiused to define a longitudinal u-shaped channel 1 10 that promotes sand bridges and more particularly sand arches over slot 104. As such, wire 100 may be referred to as a "u-wire" herein. Channel 1 10 has sidewalls 1 14 (e.g., sidewalls 1 14a and 1 14b) that, moving laterally from the center of channel 1 10 to the side flanks 108, extend outward. Put another way, in the configuration illustrated, sidewalls 1 14 slope inward from corners 107 and away from slot 140 toward an apex 1 15 (deepest portion) of channel 1 10. The portions of sidewalls 1 14b and 1 14a adjacent to a portion of slot 140 can cooperate to direct sand away from that portion of slot 140 and into channel 1 10 allowing sand to accumulate into a base for arch formation. [0044] According to one embodiment, sidewalls 1 14a, 1 14b may be formed by a continuous curve, with the radius of the curve selected to control the maximum slope of sidewalls 1 14a, 1 14b and depth of channel 1 10. In the curved sidewall embodiment of FIG. 5A, the sidewalls have a maximum slope angle a proximate to the corners 107 with side flanks 108 (proximate to slot 140). The maximum slope angle a of sidewalls 1 14 can be selected as needed or desired. According to one embodiment, the maximum slope angle of sidewalls 1 14 can be 5° - 80 °, and more preferably 30° - 80°, though higher or lower maximum slope angles may be used in various embodiments. Even more preferably, the maximum slope angle a of sidewalls 1 14 may be 25° - 55°. In some embodiments, a is approximately 35°. In some embodiments, the sidewall shape can be selected so that the maximum slope angle a is approximately the angle of repose of the sand (formation sand, gravel pack aggregate or other particles) that will be screened out by the screen. The shape of channel 1 10, maximum slope angle and other characteristics of an indented wire, including but not limited to, width 120, height 122, side flank taper angle 128, can be optimized based on the size of particles, sphericity of particles, moisture, slot width size, flow velocities and other factors.

[0045] According to one embodiment, the outer surface 1 12 of the wire 100 can be configured so that wire 100 forms a predominately sinusoidal, wave or serrated type profile when the wire is wrapped in a spiral. FIG. 5B illustrates, for example, that the outer surface of wire 100 is shaped to produce a sinusoidal profile 150 when wire 100 is wrapped. A more "v"-shaped channel 1 10 will produce a serrated type profile. The sinusoidal or serrated shape can be selected so that the slope angle (or maximum slope angle) of the sidewalls 1 14 is a desired angle selected to promote sand bridging.

[0046] The concave shape of channel 1 10 allows sand 152 to accumulate in channel 1 10 to form the foundation for a stable arch. Thus, as illustrated in FIG. 5C, the shape of channel 1 10 is selected to induce formation of stable permeable sand arches (e.g., sand arch 154) over slot 140 between adjacent wraps of wire 100. The indented shape of outer surface 1 12 promotes the flow of particles into channel 1 10 where the particles can form the base(s) (e.g., arch bases 156) of sand arch(es) over the slot 140. An arch 154 can be self- supporting and less prone to collapse compared to the sand bridges formed by conventional wire-wrapped screens.

[0047] As pressure increases, the sand particles at the base of the arch (area of maximum force/compaction) will naturally be ground into finer particles. In the prior designs, there was little to prevent these finer particles from entering and plugging the slot. However, in the embodiment of FIG. 5, the finer particles are more likely to be created in the indented area and will be prevented from entering the slot by the sidewalls 1 14.

[0048] The embodiment of FIG. 5 promotes earlier formation of sand bridges than conventional wires, providing sand control earlier in the life of the well. Moreover, by providing a shape that provides more stable arches and managing where natural compaction happens, embodiments described herein can extend the life screens. Thus, embodiments can promote the formation of more stable sand bridges than formed by prior wire-wrapped sand control devices while potentially reducing the creation of fine particles that can enter the slot.

[0049] Referring to FIGS. 6A and 6B, FIG. 6A provides a graphical representation of flow through one embodiment of a screen formed by conventional wire 50 and FIG. 6B provides a graphical representation of flow through one embodiment of screen formed of wire 100. While FIG. 6A and 6B are based on simulations using water, the respective flow pipes 55, 200 illustrate that the flow associated with embodiments of the present invention differs from the flow achieved by the conventional wire 50.

[0050] In conventional wire-wrapped screens having a flat outer surface, flow tends to significantly converge prior to reaching the slot as illustrated by flow pipes 55. This results in a relatively large increase in velocity to the outside of the slot with the flow carrying particles toward the slot. The high velocity fluid asserts hydraulic load on any sand bridge that forms (e.g., sand bridge 54 of FIG. 2), forcing the sand bridge to collapse. Furthermore, the converging flow may also carry small particles that cause erosion through the slot at higher velocities.

[0051 ] As illustrated by flow pipes 200 of FIG. 6B, on the other hand, the flow barely converges, if at all, at the slot. Instead, in the embodiment illustrated in FIG. 6B, a portion of the flow is diverted to channel 1 10. This has several potential effects. First, in order for diverted fluid to reach the slot 140, the fluid may circulate in channel 1 10 increasing the likelihood that any sand carried in the fluid will be deposited in the channel 1 10, thus promoting the aggregation of particles into a stable arch base. Second, the reduced convergence of fluid may result in reduced hydraulic load on any sand bridge that forms when compared to conventional designs. Moreover, it is believed that diverting a portion of the flow into channel 1 10 reduces erosion by reducing the number or velocity of fine particles flowing through the slot.

[0052] In the embodiment of FIGS. 5 and 6B, wire 100 is generally keystone shaped with the side flanks 108 converging from corners 107 to the nose (from the outer ends of side flanks 108 to the inner ends of side flanks 108). The keystone shape is, however, just one example of a wire profile and other embodiments may use wires having different profiles. As illustrated in FIG. 7, for example, a wire may have a house-shaped profile in which the side flanks are parallel for an outermost portion 302 and then converge for a second portion 304. In some cases, such as illustrated in FIG. 8, the outermost portion 402 in which the side flanks are parallel may be relatively short to create a hybrid-keystone profile. FIG. 7 also illustrates other example embodiments of wire profiles in addition to the profiles of FIG. 5 and FIG. 8.

[0053] Moreover, while the indented bridge-promoting feature of FIG. 5 is formed as a concave channel 1 10, the indented bridge-promoting feature may have other shapes. As illustrated in FIG. 7 and FIG. 8, for example, wires may have concave, chevron, square, polygon or otherwise shaped indented features, such as channels. The "chevron" wires, for example, have a sand bridge promoting channel defined by straight sidewalls that diverge laterally outward moving outward from the base of the channel, whereas the "polygon" wires have a bridge promoting channel defined by multi-faceted sidewalls that diverge laterally outwards. The maximum slope angle a of the sidewalls can be selected as needed or desired. According to one embodiment, the maximum slope angle of the sidewalls of "chevron" and "polygon" configurations can be 5° - 80 °, though higher or lower maximum slope angles may be used in various embodiments. Even more preferably, the maximum slope angle a is 5° - 80 °, and even more preferably 25° - 55°. In some embodiments, the sidewall shape can be selected so that the maximum slope angle a is approximately the angle of repose of the sand (formation sand, gravel pack aggregate, manmade proppant or other particles) that will be screened out. FIGS. 7 and 8 also illustrates a square configuration in which the channel sidewalls are straight and a is 90°.

[0054] The embodiments of FIGS. 5, 6B, 7 and 8 are provided by way of example and not limitation.

The skilled artisan will appreciate from the foregoing that a variety of other channel shapes can be used (e.g., a channel with a profile defined by three walls (e.g., angled or curved sidewalls and a channel floor)). The channel may run all or a portion of the length of the wire. Moreover, in some embodiments, the wire may have multiple channels (e.g., two channels separated by a central rib). Furthermore, the bridge promoting features may include a series of short channels, or other indented shaped features (e.g., dimples) selected to promote sand arch formation. The bridge promoting features can be separated from the slot by a wall having a desired slope angle/maximum slope angle, including but not limited to a slope angle that is approximately the angle of repose of selected particulates in the well.

The shape, dimensions and angles of the wire can be optimized based on the spacing between wraps, sphericity of sand (formation produced sand, gravel pack aggregate or other particles), sand size and size distribution, moisture, angle of installation and other factors. [0056] According to one embodiment, a wire may be shaped when the wire is formed, during wrapping or through a post-wrapping process. The wire may be formed from materials suitable for use as a sand screen in a hydrocarbon well. Materials include, but are not limited to, 304, 304L, 316, 316L and 321 , 410 stainless steels, Alloy 400, Alloy 600, Ally C- 276 alloys or other materials.

[0057] Embodiments described herein may be used in a variety of well screen devices including, but not limited to, slip-on wire wrapped screens, tightly fit or direct wire-wrap screens, gravel packs, single or multi-screen prepacks and other devices known in the art. FIG. 4, for example, is a diagrammatic representation of one embodiment of a well screen assembly that can incorporate various embodiments of wire-wrapped screens. FIGS. 9A-9D are diagrammatic representations of another embodiment of a well screen assembly 500. Well screen assembly 500 includes a slip-on wire-wrapped screen 520 disposed about a base pipe 510, which can be a perforated base pipe as illustrated in FIG. 9B or an unperforated base pipe. Screen 520 can screen out particulates prior to production fluid flowing into pipe 510 through apertures 512 or otherwise flowing into the base pipe.

[0058] Slip-on wire wrapped screen 520 comprises an outer wire or wires 525 wound around longitudinal supports 530. Wraps of outer wire 525 cross the longitudinal supports 530 to form a tubular grid. Although shown with a plurality of substantially parallel longitudinal supports 530 oriented along the length of the screen 520, the supports 530 can be arranged differently. For example, in some instances, supports 530 can be substantially helical at a lesser pitch than the wrapping of the outer wire 525. In the example of FIG. 9A, the perimeter of wire-wrapped screen 520 exhibits a substantially circular geometry, but could be other shapes (e.g., polygonal and/or other shapes). Outer wire 525 can be a wire configured to promote bridge formation or reduce erosion as discussed above.

[0059] As noted above screen 520 may be a slip-on wire wrapped screen. To this end, the end wraps of wire 525 or the ends of the longitudinal supports 530 can be bonded or otherwise coupled to mounting rings 352. Wire 525 may also be bonded (e.g., welded, brazed, and/or otherwise bonded) or otherwise coupled to supports 530 at intersection points. Slip-on wire wrapped screen 520 can be assembled and then slipped over base pipe 510 so that the mounting rings 532 can be bonded or otherwise coupled to the outer surface of base pipe 510.

[0060] While embodiments have been discussed primarily with respect to wire-wrapped screens, the teachings herein can apply to other devices. For example, FIG. 10A illustrates one embodiment of a slotted liner 700 containing slots 710 extending through the outer wall of the slotted liner. Indented features 712 can be disposed adjacent to the slots to promote sand arching over the slots. For example, as shown in FIG. 10B, shaped channels can be machined into the outer surface of the slotted liner. The indented features 712 may have a variety shapes, including, but not limited to, concave, chevron, square or polygon. While not illustrated, it can be understood that a slotted liner can be configured so that the indented features 712 form a predominantly wave, sinusoidal or serrated profile over the entire circumference or a portion of the circumference.

[0061 ] FIG. 1 1 A, FIG. 1 1 B and FIG. 1 1 C provide example lab test data for a "constant draw down test" using a screen formed of a standard keystone-shaped flat wire by Packers Plus of Calgary, Alberta Canada (the "conventional screen") and a screen formed of a wire having the u-wire profile 800 illustrated in FIG. 1 1 D (the "u-wire screen"). Both screens were 10 gauge screens— screens having a nominal slot width of .010 inches (254 Micron)— and the test sand had a d 10 of 300 micron.

[0062] With respect to FIG. 1 1 A, the screens were tested using fluid without a sand pack (first test), then tested with the sand pack (second test), and then tested again without the sand pack (third test). In the first test without the sand pack, the u-wire screen yielded a slightly lower permeability of 3297 darcy. However, in the third test performed after testing the screens with a sand pack, the u-wire screen yielded a permeability of 2062 darcy, whereas the screen only yielded a permeability of 1577 darcy. This indicates that the u-wire screen experienced significantly less plugging.

[0063] With reference to the sand pack test, the u-wire screen yielded a permeability through the sand pack of 347 milli-darcy, whereas the conventional screen yielded a permeability through the sand pack of 314 milli-darcy. Furthermore, the u-wire screen yielded a permeability of the system (including through the screen) of 474 milli-darcy whereas the conventional screen yielded a permeability of 425 milli-darcy. This indicates that a wire- wrapped screen formed according to embodiments described herein can result in higher permeability and, therefore, production than a conventional wire-wrapped screen.

[0064] FIG. 1 1 B illustrates that the produced solids were roughly equivalent indicating that the u- wire screen achieved the same filtration as the conventional screens while allowing for higher production rates.

[0065] With respect to FIG. 1 1 C, the graph therein provides sample flow rate data for the u-wire screen (line 802) and the conventional screen (804). In this example, the u-wire screen achieved approximately a 16.7 % better flow rate than the conventional screen for the same draw down.

[0066] FIG. 12 is a chart illustrating test results of a constant rate test run at 240 ml/min for a u-wire and a conventional screen, with line 900 representing the results for the u-wire screen and line 902 representing the results for the conventional screen. This data indicates that the u- wire screen exhibited delayed plug-off compared to the conventional screen.

[0067] Although the invention has been described with respect to specific embodiments thereof, these embodiments are merely illustrative, and not restrictive of the invention. Rather, the description is intended to describe illustrative embodiments, features and functions in order to provide a person of ordinary skill in the art context to understand the invention without limiting the invention to any particularly described embodiment, feature or function. While specific embodiments of, and examples for, the invention are described herein for illustrative purposes only, various equivalent modifications are possible within the spirit and scope of the invention, as those skilled in the relevant art will recognize and appreciate. As indicated, these modifications may be made to the invention in light of the foregoing description of illustrated embodiments of the invention and are to be included within the spirit and scope of the invention. Thus, while the invention has been described herein with reference to particular embodiments thereof, a latitude of modification, various changes and substitutions are intended in the foregoing disclosures, and it will be appreciated that in some instances some features of embodiments of the invention will be employed without a corresponding use of other features without departing from the scope and spirit of the invention as set forth. Therefore, many modifications may be made to adapt a particular situation or material to the essential scope and spirit of the invention.

[0068] Reference throughout this specification to "one embodiment", "an embodiment", or "a specific embodiment" or similar terminology means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment and may not necessarily be present in all embodiments. Thus, respective appearances of the phrases "in one embodiment", "in an embodiment", or "in a specific embodiment" or similar terminology in various places throughout this specification are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, or characteristics of any particular embodiment may be combined in any suitable manner with one or more other embodiments. It is to be understood that other variations and modifications of the embodiments described and illustrated herein are possible in light of the teachings herein and are to be considered as part of the spirit and scope of the invention. [0069] In the description herein, numerous specific details are provided, such as examples of components and/or methods, to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that an embodiment may be able to be practiced without one or more of the specific details, or with other apparatus, systems, assemblies, methods, components, materials, parts, and/or the like. In other instances, well-known structures, components, systems, materials, or operations are not specifically shown or described in detail to avoid obscuring aspects of embodiments of the invention. While the invention may be illustrated by using a particular embodiment, this is not and does not limit the invention to any particular embodiment and a person of ordinary skill in the art will recognize that additional embodiments are readily understandable and are a part of this invention.

[0070] As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, product, article, or apparatus that comprises a list of elements is not necessarily limited only those elements but may include other elements not expressly listed or inherent to such process, product, article, or apparatus.

[0071 ] Furthermore, the term "or" as used herein is generally intended to mean "and/or" unless otherwise indicated. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present). As used herein, a term preceded by "a" or "an" (and "the" when antecedent basis is "a" or "an") includes both singular and plural of such term, unless clearly indicated otherwise (i.e., that the reference "a" or "an" clearly indicates only the singular or only the plural). Also, as used in the description herein, the meaning of "in" includes "in" and "on" unless the context clearly dictates otherwise.