CONTROL SCREEN ASSEMBLY
Technical Field of the Invention
[0001] The present invention relates generally to control screens for
subterranean fluid production and, more particularly (although not necessarily
exclusively), to a control screen assembly having a rigid member that includes an
opening providing fluid communication between a filter medium and an internal flow
path of a base pipe.
Background
[0002] Hydrocarbons can be produced through a wellbore traversing a
subterranean formation. In some cases, the formation may be unconsolidated or
loosely consolidated. Particulate materials, such as sand, from these types of
formations may be produced together with the hydrocarbons. Production of particulate
materials presents numerous problems. Examples of problems include particulate
materials being produced at the surface, causing abrasive wear to components within a
production assembly, partially or fully clogging a production interval, and causing
damage to production assemblies by collapsing onto part or all of the production
assemblies.
[0003] Gravel packing the well adjacent to the production interval can assist in
stabilizing the formation surrounding the production interval and In filtering particulate
materials before the particulate materials enter the production pipe. Gravel packing
can include lowering a sand control screen into the wellbore on a work string to a
position proximate a selected production interval. A fluid slurry, including a liquid
carrier and a material such as gravel, is pumped down the work string and into the well
annulus formed between the sand control screen and a perforated well casing or open
hole production zone. The gravel is deposited in the well annulus to form a gravel
pack. The gravel pack is highly permeable to hydrocarbon fluids, but can block
particulate material carried in the hydrocarbon fluids. The gravel pack and sand control
screen can also stabilize the formation surrounding the production interval to prevent
fonnation collapses.
[0004] Complete gravel packing at a selected production interval can be difficult
to achieve due to the formation of sand bridges and other complications experienced
when pumping the fluid slurry down the work string. Expandable sand control screens
can be used in place of gravel packs that may be less problematic to locate in the
wellbore and may provide similar filtering and formation stability as gravel packs.
[0005] One expandable sand control screen is a control screen assembly that
includes a swellable material, such as a high-swelling rubber, and a filter device on the
exterior of the swellable material. The swellable material can be located proximate the
production interval and, when activated by a fluid, expand to displace the filter device to
the wellbore. The assembly includes openings through which hydrocarbon fluids are
directed by the filter device into a base pipe. A telescoping piston can be located in the
opening and can support the filter device as the swellable material expands. This type
of expandable sand control screen can be effective in filtering and providing formation
stability.
[0006] In some applications, however, the swellable material may swell into the
openings or otherwise swell to block, partially or completely, fluid communication
between the interior and exterior of a base pipe. Blocking fluid communication may
result in the swellable material partially or completely plugging the opening to the base
pipe. A rework of the control screen assembly may be required to alleviate the
plugging. Reworks cost substantial time and money because they require suspension
of hydrocarbon production for a measurable amount of time and require duplication of
work in locating the control screen assembly in the wellbore.
[0007] Therefore, screen assemblies that can provide radial support to
formations and reduce or eliminate plugging are desirable. Screen assemblies that
eliminate or reduce reworks are desirable.
Summary
[0008] Certain embodiments of the present invention are directed to screen
assemblies that can filter particulate materials in hydrocarbon fluids from a
hydrocarbon-bearing subterranean formation and reduce or eliminate plugging.
Reducing or eliminating plugging can reduce or eliminate a need for reworks. The
screen assemblies may include a swellable material without requiring an opening to be
created in the swellable material. Certain screen assemblies can provide stability to a
wellbore traversing a subterranean formation.
[0009] In one aspect, a screen assembly that can be disposed In a bore is
provided. The screen assembly includes a base pipe, a rigid member, a swellable
material, and a filter medium. The base pipe includes a sidewall portion with an
opening. The rigid member is disposed exterior to a first portion of the base pipe. The
rigid member includes an opening in fluid communication with the opening of the base
pipe. The swellable material is disposed exterior to a second portion of the base pipe.
The filter medium is at least partially disposed exterior to the swellable material and is
in fluid communication with the opening of the rigid member. In response to contact
with an activating fluid, the swellable material can expand and displace at least part of
the filter medium toward a surface of the bore.
[0010] In at least one embodiment, the screen assembly includes a piston
disposed in the opening of the rigid member and coupled to the base pipe. The piston
includes a telescoping portion coupled to the filter medium. The telescoping portion
can radially extend from the opening of the rigid member when the swellable material
expands. The filter medium can filter fluids and direct the fluids to an internal flow path
of the base pipe through the piston.
[0011] In at least one embodiment, the screen assembly includes a material
between the filter medium and the rigid member. The material includes at least one of
a non-swelling media or a low-swelling media. The material can provide a temporary
seal between the filter medium and the rigid member. In some embodiments, the
material includes rubber.
[0012] In at least one embodiment, the activating fluid to which the swellable
material is responsive includes at least one of a hydrocarbon fluid, water, or a gas.
[0013] In at least one embodiment, the filter medium has a cross-sectional shape
of at least one of a kidney shape, an oval, a circle, or a rectangle.
[0014] In at least one embodiment, the rigid member is a ring that is at least one
of a metal, a composite polymer, or a non-swelling rubber compound.
[0015] In another aspect, a screen assembly that can be disposed in a bore is
provided. The screen assembly includes a base pipe, a rigid member, a swellable
material, and a plurality of filter mediums. The base pipe includes a sidewall portion
that has a plurality of openings. The rigid member is disposed exterior to a first portion
of the base pipe and includes a plurality of openings. Each opening of the plurality of
openings of the rigid member is in fluid communication with an opening of the plurality
of openings of the sidewall portion. The swellable material is disposed exterior to a
second portion of the base pipe. The plurality of filter mediums are at least partially
disposed exterior to the swellable material. Each of the plurality of filter mediums is in
fluid communication with at least one of the plurality of openings of the rigid member.
In response to contact with an activating fluid, the swellable material can expand and
displace at least part of each of the plurality of filter mediums toward a surface of the
bore.
[0016] In another aspect, a screen assembly that can be disposed in a bore is
provided. The screen assembly includes a base pipe, a first rigid member, a second
rigid member, a swellable material, and a plurality of filter mediums. The base pipe
includes a sidewall portion with a first plurality of openings and a second plurality of
openings. The first plurality of openings are located at a first portion of the base pipe.
The second plurality of openings are located at a second portion of the base pipe. The
first rigid member is disposed exterior to the first portion of the base pipe. The second
rigid member is disposed exterior to the second portion of the base pipe. The swellable
material is disposed exterior to a third portion of the base pipe. The plurality of filter
mediums are at least partially disposed exterior to the swellable material. Each of the
plurality of filter mediums is in fluid communication with at least one opening of the first
plurality of openings or the second plurality of openings. In response to contact with an
activating fluid, the swellable material can expand and displace at least part of each of
the plurality of filter mediums toward a surface of the bore.
[0017] In at least one embodiment, the third portion of the base pipe is located
between the first portion and the second portion.
[0018] In at least one embodiment, each of the plurality of filter mediums is in
fluid communication with at least one opening of the first plurality of openings or the
second plurality of openings through at least one of a plurality of openings of the first
rigid member or the second rigid member.
[0019] In at least one embodiment, each of the first rigid member and the second
rigid member includes a first receiving portion and a second receiving portion. The first
receiving portion can support a first filter medium of the plurality of filter mediums in a
running configuration. The second receiving portion can support a second filter
medium of the plurality of filter mediums in the running configuration. In some
embodiments, the first receiving portion and the second receiving portion define
grooves for supporting the first filter medium and the second filter medium of the
plurality of filter mediums in the running configuration. In some embodiments, the
second rigid member is rotated forty-five degrees relative to the first rigid member and
the first receiving portion of the first rigid member is aligned with the second receiving
portion of the second rigid member.
[0020] In at least one embodiment, the activating fluid is at least one of a
hydrocarbon fluid, water, or a gas.
[0021] In at least one embodiment, each of the plurality of filter mediums has a
cross-sectional shape of at least one of: a kidney shape; an oval; a circle; or a
rectangle.
[0022] In at least one embodiment, each of the first rigid member and the second
rigid member is a ring that is at least one of: a metal; a composite polymer; or a non-
swelling rubber compound.
[0023] These Illustrative aspects and embodiments are mentioned not to limit or
define the invention, but to provide examples to aid understanding of the inventive
concepts disclosed in this application. Other aspects, advantages, and features of the
present invention will become apparent after review of the entire application.
Brief Description of the Drawings
[0024] Figure 1A is a schematic illustration of a well system having screen
assemblies in a running configuration according to one embodiment of the present
invention.
[0025] Figure 1B is a schematic illustration of a well system having screen
assemblies in an operating configuration according to one embodiment of the present
invention.
[0026] Figure 2 is a side view of a screen assembly of Figure 1A in a running
configuration according to one embodiment of the present invention.
[0027] Figure 3 is a side view of a section of the screen assembly of Figure 2 in
a running configuration.
[0028] Figure 4A is a cross sectional view along line 4A-4A of a screen assembly
of Figure 1A in a running configuration according to one embodiment of the present
invention.
[0029] Figure 4B is a cross sectional view along line 4B-4B of a screen assembly
of Figure 18 in an operating configuration according to one embodiment of the present
invention.
[0030] Figure 5A is a cross sectional view along line 5A-5A of the screen
assembly of Figure 1A in a running configuration according to one embodiment of the
present invention.
[0031] Figure 58 is a cross sectional view along line 5B-5B of the screen
assembly of Figure 1B in an operating configuration according to one embodiment of
the present invention.
[0032] Figure 6A is a cross sectional view of a screen assembly in a running
configuration according to one embodiment of the present invention.
[0033] Figure 68 is a cross sectional view of a screen assembly in an operating
configuration according to one embodiment of the present invention.
[0034] Figure 7A is a cross sectional view of a second embodiment of a screen
assembly in a running configuration according to one embodiment of the present
invention.
[0035] Figure 7B is a cross sectional view of the second embodiment of the
screen assembly of Figure 7A in an operating configuration according to one
embodiment of the present invention.
[0036] Figure 8 is a side view of a rigid member capable of being included in a
screen assembly according to one embodiment of the present invention.
[0037] Figure 9 is a cross section view along line 9-9 of the rigid member of
Figure 8 according to one embodiment of the present invention.
Detailed Description
[0038] Certain aspects and embodiments of the present Invention relate to
screen assemblies capable of being disposed in a bore, such as a wellbore, of a
subterranean formation for use in producing hydrocarbon fluids from the formation.
The screen assemblies may be configured to support filter mediums and reduce or
eliminate plugging by swellable material. A screen assembly according to some
embodiments includes filter mediums supported by a rigid member located exterior to
part of a base pipe. The rigid member can include openings through which the filter
mediums can be in fluid communication with an inner diameter of the base pipe.
Swellable material can be disposed exterior to a second part of the base pipe and
adjacent to the rigid member. The filter mediums can be displaced by the swellable
material to contact a wall of the bore and the rigid members can help reduce or prevent
plugging of screen assembly openings. In some embodiments, the screen assembly is
a sand control screen assembly that can reduce or prevent production of particulate
materials from a well that traverses a hydrocarbon bearing subterranean formation or
operates as an injection well.
[0039] Figure 1A shows a well system 10 with screen assemblies according to
certain embodiments of the present invention. The well system 10 includes a bore that
is a wellbore 12 that extends through various earth strata. The wellbore 12 has a
substantially vertical section 14 and a substantially horizontal section 18. The
substantially vertical section 14 includes a casing string 16 cemented at an upper
portion of the substantially vertical section 14. The substantially horizontal section 18 is
open hole and extends through a hydrocarbon bearing subterranean formation 20.
[0040] A tubing string 22 extends from the surface within wellbore 12. The
tubing string 22 can provide a conduit for fomnation fluids to travel from the substantially
horizontal section 18 to the surface. Screen assemblies 24, 26 are positioned with the
tubing string 22 in the substantially horizontal section 18. The screen assemblies 24,
26 are shown in a running or unextended configuration. In some embodiments, screen
assemblies 24, 26 are sand control screen assemblies that can filter particulate
materials from hydrocarbon fluids, direct the hydrocarbon fluids to an inner diameter of
the tubing string 22, and stabilize the formation 20.
[0041] Figure 1B shows the well system 10 with screen assemblies 24, 26 in an
operating or a radially expanded configuration. Each of the screen assemblies 24, 26
can include a base pipe, a rigid member, swellable material, and filter mediums. The
rigid member may be a ring made from a metal, composite polymer, non-swelling
rubber compound, or the like and may be disposed exterior to part of the base pipe.
Examples of metals from which the rigid member may be made include steel, iron,
brass, copper, bronze, tungsten, titanium, cobalt, nickel, and a combination of these or
other types of materials. The swellable material may be a relatively high swelling
rubber or polymer and may be disposed exterior to another part of the base pipe. The
filter mediums may be coupled to the exterior of the swellable material and supported
by part of the rigid member at least in a running configuration.
[0042] When an activating fluid contacts the screen assemblies 24, 26, the
swellable material of each of the screen assemblies can expand. Expansion of the
swellable material can displace filter mediums of the screen assemblies 24, 26 to
contact a surface of wellbore 12. The activating fluid may be any fluid to which the
swellable material responds by expanding. Examples of activating fluid include
hydrocarbon fluids, water, and gas.
[0043] Screen assembly 24 may be a screen assembly that includes filter
mediums that are laterally and longitudinally adjacent to each other. Screen
assemblies 26 may be screen assemblies that include filter mediums that are only
laterally adjacent to each other.
[0044] Figures 1A and 1B show tubing string 22 with screen assemblies 24, 26.
Tubing strings according to various embodiments of the present invention, however,
may include any number of other tools and systems in addition to screen assemblies
24, 26. Examples of other tools and systems include fluid flow control devices,
communication systems, and safety systems. Tubing string 22 may also be divided
into intervals using zonal isolation devices such as packers. Zonal isolation devices
may be made from materials that can expand upon contact with a fluid, such
hydrocarbon fluids, water, and gas.
[0045] In addition, figures 1A and 1B show screen assemblies according to
certain embodiments of the present invention in the substantially horizontal section 18
of the wellbore 12. Various screen assembly embodiments according to the present
invention, however, can be used in deviated, vertical, or multilateral wellbores.
Deviated wellbores may include directions different than, or in addition to, a general
horizontal or a general vertical direction. Multilateral wellbores can include a main
wellbore and one or more branch wellbores. Directional descriptions are used herein to
describe the illustrative embodiments but, like the illustrative embodiments, should not
be used to limit the present invention.
[0046] As stated above, certain embodiments of the present invention can be
disposed in an Injection well. In an injection well, water or other fluid is injected into the
well to increase flow of hydrocarbon fluids to a nearby production well. Screen
assemblies according to certain embodiments of the present invention can be disposed
in the injection well to provide support during and after the fluid injection process. In
some embodiments, injected fluid exits a base pipe through openings in the base pipe,
in a rigid member and in a filter medium supported by the rigid member. The filter
medium may be a support member that does not include filtration material, but includes
structure capable of supporting a formation.
[0047] Screen assemblies according to some embodiments of the present
invention can be disposed in a cased hole completion. In a cased hole completion, a
large diameter pipe is positioned between a production string and a formation. The
large diameter pipe may be a base pipe with openings in a sidewall portion of the base
pipe. A screen assembly can be positioned exterior to the large diameter pipe. The
screen assembly can include a rigid member with an opening that is in fluid
communication with an opening in the sidewall portion. A filter medium can be
supported by the rigid member and can be in fluid communication with the opening in
the sidewall portion through the rigid member opening.
[0048] Figures 2 and 3 show a more detailed view of screen assembly 24 in a
running configuration. The screen assembly 24 depicted in the figures includes three
rigid members 50, 51, 53 located circumferential to a base pipe 52. The rigid members
50, 51, 53 may be coupled to the base pipe. In other embodiments, a base pipe is
provided that includes one or more rigid members. Screen assemblies according to
various embodiments of the present invention can include any number of rigid
members. For example, screen assemblies 26 in Figures 1A and 1B include two rigid
members. In other embodiments, screen assemblies include one rigid member. Rigid
members 50, 51, 53 may be constructed from any material capable of retaining a
general shape upon contact with fluids such as hydrocarbon fluids, gas, and water.
Examples of material from which rigid members 50, 51, 53 can be constructed include
metal such as steel. In some embodiments, rigid members 50, 51, 53 are rings
constructed from steel. The rigid members 50, 51, 53 may include openings that are in
fluid communication with openings in a sidewall of the base pipe 52. In some
embodiments, each of the rigid members 50, 51, 53 includes four openings and each of
the four openings is in fluid communication with openings in a sidewall of a base pipe.
[0049] Swellable material (not shown) can be disposed circumferential to a
second portion of the base pipe 52 and between the rigid members 50, 51, 53. Filter
mediums 58 are positioned on an exterior of the swellable material and can be
supported by rigid members 50, 51, 53 at least in a running configuration. Each of the
filter mediums 58 may be supported by one of the rigid members 50, 51, 53. For
example, filter medium 58A is supported by rigid member 50 and filter mediums 58B,
58C is supported by rigid member 51. In some embodiments, each of the filter
mediums 58 are supported by being retained, at least temporarily, by one of the rigid
members 50, 51, 53. For example, each of the filter mediums 58 can be retained by
grooves in one or more rigid members 50, 51, 53 in a running configuration and can be
allowed to detach from the grooves in an operating configuration. In other
embodiments, each of the filter mediums 58 are retained by the grooves in one or more
rigid members 50, 51, 53 in the operating configuration or otherwise supported by a
component disposed in one of the rigid members 50, 51, 53, such as a telescoping
piston.
[0050] The filter mediums 58 may be filtration tubes that extend longitudinally
from a rigid member and have a substantially rectangular surface shape. In some
embodiments, the filter mediums 58 have a surface shape that resembles, for example,
a helicopter blade. Each of the filter mediums 58 can include perforations 59 that allow
hydrocarbon fluids to enter the filter mediums 58 for filtration and direction to an inner
flow path of the base pipe 52 through openings in one or more of the rigid members 50,
51, 53. In the running configuration shown in Figures 2 and 3, the filter mediums 58 are
adjacent to each other. The swellable material can be configured to expand and
displace the filter mediums 58 radially during an operating configuring. In some
embodiments, the filter mediums 58 are separated by swellable material during the
operating configuration.
[0051] Filter mediums according to some embodiments of the present invention
may be or include a control line that can be a fiber optic cable in communication with a
sensor capable of contacting a formation. The control line can detect conditions
associated with the formation and transmit information about the conditions to the
surface for analysis. Filter mediums may also include a fiber optic disposed in
housings of the filter mediums to provide condition information in a running
configuration or otherwise provide infomnation to protect the filter mediums.
[0052] Figures 4A and 4B show a cross-sectional view of part of the screen
assembly 24 from Figures 1A (running configuration) and 1B (operating configuration),
respectively. Figures 4A and 4B show a base pipe 52 that defines an internal flow path
54 through which hydrocarbon fluids, for example, can flow. A swellable material 56
surrounds the base pipe 52. The swellable material 56 can be attached to the base
pipe 52, such as by bonding or other suitable technique. Part of a rigid member 50 is
shown in Figure 4A, but it is distant to the cross-section shown in Figure 4A.
[0053] Filter mediums are shown as filter mediums 58A-H and are positioned on
an exterior of the swellable material 56. Figure 4A shows eight filter mediums 58A-H,
but screen assemblies according to various embodiments of the present invention can
include any number, from one to many, of filter mediums 58A-H. In some
embodiments, the filter mediums 58A-H are bonded to the exterior of swellable material
56. For example, a relatively low swelling or non-swelling material can be positioned
between the exterior of the swellable material 56 and the filter mediums 58A-H. The
filter mediums 58A-H can be bonded to the low swelling or non-swelling material and
the low swelling or non-swelling material can be bonded to the swellable material 56.
The low swelling or non-swelling material may assist in preventing the swellable
material 56 from damaging the filter mediums 58A-H upon expansion.
[0054] The swellable material 56 can expand upon contact with an activating
fluid and displace the filter mediums 58A-H to contact a fomnation 66 at an internal
diameter of a wellbore 68. In some embodiments, the filter mediums 58A-H are
filtration tubes that can filter particulate materials from hydrocarbon fluids and direct the
hydrocarbon fluids to openings in the base pipe 52. The filter mediums 58A-H
illustrated each include a housing 60 for filter material 62. The filter material 62 can
include a filtration opening 64 through which hydrocarbon fluid can be directed to an
opening in the base pipe 52. The housing 60 may be made of any suitable material
and may be partially perforated to allow hydrocarbon fluids to enter the housing 60.
The filter material 62 may be any suitable material, such as a fine mesh, that can filter
particulate materials from hydrocarbon fluid.
[0055] The filter mediums 58A-H have a kidney-shaped cross-sectional shape.
The kidney-shaped cross-section may assist in attaching the filter mediums 58A-H to
the swellable material 56 and may result in more surface area of the filter mediums
58A-H, as compared to filter mediums having a different cross-sectional shape,
contacting the wellbore 68 upon expansion of the swellable material 56. Filter mediums
according to other embodiments of the present invention, however, may have any type
of cross-sectional shape. Examples of these types of cross-sectional shapes include
an oval, a circle, a rectangle, and a combination of two or more cross-sectional shapes.
The filter mediums 58A-H can have a cross-sectional length that Is selected based on
the particular requirements of a production interval in which the screen assembly 24 is
located.
[0056] The swellable material 56 can expand upon contact with an activating
fluid, as shown in Figure 4B. The activating fluid can include hydrocarbon fluid, water,
or gas. Various techniques can be used to contact the swellable material 56 with an
activating fluid. One technique includes configuring the swellable material 56 to
expand upon contact with activating fluids already present within the wellbore when the
screen assembly 24 is installed or with activating fluids produced by the formation 66
after installation. The swellable material 56 may include a mechanism for delaying
swell to prevent swelling during installation. Examples of a mechanism for delaying
swell include an absorption delaying layer, coating, membrane, or composition.
Another technique Includes circulating activating fluid through the well after the screen
assembly 24 is installed in the well. In other embodiments, swellable material 56 is
capable of expansion upon its location in an environment having a temperature or a
pressure that is above a pre-selected threshold In addition or alternative to an activating
fluid.
[0057] Expansion of the swellable material 56 can displace the filter mediums
58A-H to contact the formation 66 at wellbore 68. The thickness of the swellable
material 56 can be optimized based on the diameter of the screen assembly 24 and the
diameter of the wellbore 68 to maximize contact area of the filter mediums 58A-H with
the wellbore 68 upon expansion. In some embodiments, part of the swellable material
56 expands between the filter mediums 58A-H and contacts the formation 66 at
wellbore 68 between the filter mediums 58A-H to conform to non-uniform wellbore
diameters. The swelled screen assembly 24 can reduce or eliminate annular flow of
hydrocarbon and other fluids, provide multiple flow paths for filtered hydrocarbon fluids,
and provide stabilization to the wellbore 68. For example, the swelled screen assembly
24 can support the formation 66 to prevent formation collapse. In some embodiments,
the swelled screen assembly 24 can provide an amount of collapse support within a
range of 500 psi to 2000 psi (3.4 MPa to 14 MPa).
[0058] Rigid members that support filter mediums according to certain
embodiments of the present invention can include pistons disposed in openings of the
rigid members. The pistons may be telescoping pistons that can support the filter
mediums in a running configuration and an operating configuration. Figures 5A and 5B
show a cross-sectional view of one of the rigid members 50 of the screen assembly 24
from Figures 1A (running configuration) and 1B (operating configuration), respectively.
The base pipe 52 includes openings 70 in a sidewall portion of the base pipe 52. The
rigid member 50 includes openings 72 that are in fluid communication with the
openings 70 of the base pipe 52. Pistons 74 are disposed in the openings 72 and can
be coupled to filter mediums. Figures 5A and 5B illustrate a rigid member 50 that can
support four filter mediums that are designated 58A, 58C, 58E, and 58G. Rigid
members according to various embodiments of the present invention, however, can
support any number of filter mediums.
[0069] The filter mediums 58A, 58C, 58E, 58G can be coupled to a low swelling
or non-swelling material 76. The low-swelling or non-swelling material 76 may assist
the rigid member 50 in supporting the filter mediums 58A, 58C, 58E, 58G by providing
a temporary seal between the filter mediums 58A, 58C, 58E, 58G and rigid member 50.
In some embodiments, the low swelling or non-swelling material 76 is a low swelling or
non-swelling rubber.
[0060] Pistons 74 may each include a telescoping portion 78 that extends
radially from the openings 72, as shown in Figure 58, when the swellable material 56
expands to displace the filter mediums 58A, 58C, 58E, 58G to contact the wellbore 68
at the formation 66. In some embodiments, grooves 80 in the rigid members 50
circumferential to the pistons 74 can receive 0-rings and/or safety catch rings. The O-
rings may provide a seal to prevent fluids from traveling between the pistons 74 and the
rigid member 50. The safety catch rings may prevent the pistons 74 from exiting the
openings 72, such as when the swellable material 56 expands.
[0061] Figures 5A and 58 show four filter mediums 58A, 58C, 58E, 58G coupled
to four pistons 74. Rigid member 51 from Figures 2 and 3 can include a similar cross-
sectional arrangement of the other four filter mediums 588, 58D, 58F, 58H shown in
figures 4A and 48. Rigid member 51 can be located a selected longitudinal distance
from the cross-section shown in figures 5A and 58. Rigid member 51 may be rotated
forty-five degrees relative to rigid member 50 to allow filter mediums 58A-H to be
positioned adjacent to each other.
[0062] Figures 6A and 6B illustrate cross-sectional side views of one
embodiment of the screen assembly 24 disposed in a wellbore 68 in a running
configuration and operating configuration, respectively. The screen assembly includes
a base pipe 52 that defines an internal flow path 54 through which hydrocarbon fluids
can travel. A rigid member 50 is disposed exterior to a first portion of the base pipe 52.
The rigid member 50 may be a ring made from a metal, composite polymer, non-
swelling rubber, or the like. Examples of metals from which the rigid member may be
made include steel, iron, brass, copper, bronze, tungsten, titanium, cobalt, nickel, and a
combination of these and other types of materials.
[0063] In some embodiments, an interface layer is disposed between the base
pipe 52 and at least part of the rigid member 50. The interface layer may bond the rigid
member 50 to the base pipe 52. The interface layer may also provide a seal between
the rigid member 50 and the base pipe 52 to prevent annular flow of fluids from
formation 66.
[0064] The base pipe 52 includes openings 70 in a sidewall portion of the base
pipe 52. The openings 70 are In fluid communication with filter mediums 58A, 58E
through openings 72 in the rigid member 50. The filter mediums 58A, 58E are
supported by the rigid member 50 in the running configuration. In each of the openings
72, a piston 74 is disposed. The pistons 74 allow for fluid communication between the
filter mediums 58A, 58E and base pipe openings 70.
[0065] Swellable material 56 is disposed exterior to a second portion of the base
pipe 52 and longitudinally adjacent to the rigid member 50. The swellable material 56
is positioned between the base pipe 52 and part of each of the filter mediums 58A,
58E. The swellable material 56 can retain an initial size during a running configuration
and can expand upon contact with an activating fluid in an operating configuration. The
swellable material 56 can displace the filter mediums 58A, 58E to contact the wellbore
68 when the swellable material 56 expands in the operating configuration.
[0066] The filter mediums 58A, 58E each include a housing 60 for filter material
62. The housing 60 includes perforations 59 through which hydrocarbon fluids
produced by the formation 66 can flow to the filter material 62. The filter material 62
can filter particulate materials from the hydrocarbon fluids and direct the filtered
hydrocarbon fluids through a filtration opening 64 to the flow path 54 through the base
pipe openings 70 and rigid member openings 72.
[0067] The pistons 74 can support the filter mediums 58A, 58E In the running
configuration and the operating configuration. For example, the pistons 74 may be
coupled to the filter mediums 58A, 58E and the pistons 74 can include telescoping
portions 78 that can extend radially from the rigid member openings 72 when the
swellable material 56 expands and displaces the filter mediums 58A, 58E. The rigid
member 50 can isolate openings from the swellable material 56 to reduce or eliminate
plugging and/or can allow the screen assembly to be constructed without requiring
openings to be included in the swellable material 56.
[0068] Screen assemblies according to certain embodiments of the present
invention can be constructed using multiple rigid members supporting multiple filter
mediums extending longitudinally along an exterior of a base pipe. Figures 7A and 7B
show a cross-sectional view of part of a screen assembly 200 with multiple rigid
members in a running configuration and an operating configuration, respectively.
[0069] The screen assembly 200 includes a base pipe 202 that has openings
204 in a sidewall portion of the base pipe 202. The base pipe 202 can define an
internal flow path 203 for hydrocarbon fluids produced by a formation 205. A first rigid
member 206 is disposed exterior to a first circumferential portion of the base pipe 202.
A second rigid member 208 is disposed exterior to a second circumferential portion of
the base pipe 202. Swellable material 210 is disposed exterior to a third circumferential
portion of the base pipe 202 between the first circumferential portion and the second
circumferential portion. Second swellable material 212 may also be disposed exterior
to a fourth circumferential portion of the base pipe 202 and longitudinally adjacent to
the second rigid member 208.
[0070] A filter medium 214 is disposed exterior to the swellable material 210 and
of part of the first and second rigid members 206, 208. The filter medium 214 can be in
fluid communication with the internal flow path 203 through two base pipe openings
204 and openings 216 in each of the first rigid member 206 and the second rigid
member 208. The filter medium 214 includes a housing 218 with selected perforations
220 that allow hydrocarbon fluid to flow to a filter media 222 disposed within the
housing 218. The filter media 222 can filter particulate materials from hydrocarbon fluid
and direct the filtered hydrocarbon fluid to one or both openings 216 in the first and
second rigid members 206, 208.
[0071] A second filter medium 221 is disposed exterior to the second swellable
material 212 and part of the second rigid member 208. The second filter medium 220
may be constructed similar to the filter medium 214 and be configured to direct filtered
hydrocarbon fluid to a second opening 223 in second rigid member 208 or to an
opening in another rigid member (not shown).
[0072] Each of the openings 216 has a piston 224 disposed within it. Each of the
pistons 224 can be coupled to the filter medium 214 and each of the pistons 224 can
include a telescoping portion 226. The second opening 223 includes a second piston
228 that is constructed similar to pistons 224.
[0073] Upon contact with an activating fluid, the swellable material 210 and
second swellable material 212 can expand radially to displace the filter medium 214
and second filter medium 220 to contact with the formation 205. Examples of the
activating fluid include hydrocarbon fluid, water, and gas. The telescoping portion 226
of pistons 224 can extend radially from openings 216 to provide support to the filter
medium 214 during the operating configuration and provide a conduit through which
hydrocarbon fluid can flow from the filter media 222 through openings 216 to the
internal flow path 203. The second piston 228 may perform similarly for the second
filter medium 220 during the operating configuration.
[0074] Figures 7A and 7B Illustrate rigid members located proximate to ends of
filter mediums. In other embodiments, rigid members are located proximate to other
portions of filter mediums. For example, a rigid member can support a filter medium
proximate to a middle of the filter medium during a running configuration and Include
openings through which hydrocarbon fluid can flow from the filter medium to an Intemal
flow path of a base pipe.
[0075] Rigid members according to various embodiments of the present
invention can be constructed using a variety of designs. Figure 8 is a side view of one
embodiment of the rigid member 50 from Figures 6A-6B. The rigid member 50 is a ring
that can be located exterior to a portion of a base pipe. The rigid member 50 includes a
sloped portion 302, an intervening portion 304, and a filter medium support portion 306.
The sloped portion 302 has a sloping shape to prevent damage to the remaining
portions of the rigid member 50 during installation of the rigid member 50 in a bore.
The intervening portion 304 may connect the sloped portion 302 and the filter medium
support portion 306 and provide stability to the rigid member 50 to reduce or prevent
damage to filter mediums or other components of a screen assembly when installed in
the wellbore.
[0076] The filter medium support portion 306 can provide support to filter
mediums of the screen assembly. The filter medium support portion 306 includes
receiving portions 308A-C. Each of the receiving portions 308-C includes a respective
opening 310A-C and each of the receiving portions 308A-C can support a respective
filter medium. For example, each of the receiving portions 308A-C may be grooves that
can receive a filter medium in a running configuration and allow the filter medium to
detach from the grooves during an operating configuration. The openings 310A-C can
provide fluid communication to an internal flow path of a base pipe and can receive a
piston for supporting the filter mediums during the running configuration and an
operating configuration.
[0077] The receiving portions 308A-C can be staggered to support overlap of
filter mediums and to define grooves. For example, Figure 8 shows one receiving
portion 308B having a different length than the other receiving portions 308A, 308C.
Figure 9 is a cross-sectional view of rigid member 300 along line 9-9. Openings 310A-
D are shown in Figure 9 as defined by grooves in filter medium support portion 306. A
filter medium can be positioned over 310A and coupled to a piston disposed in opening
31OA. Similarly, each of openings 310B-D can be associated with a respective filter
medium.
[0078] The rigid member 50 may be made from a metal, composite polymer,
non-swelling rubber, or the like. Examples of metals from which the rigid member 50
may be made include steel, iron, brass, copper, bronze, tungsten, titanium, cobalt,
nickel, and a combination of these or other types of materials.
[0079] Screen assemblies according to some embodiments of the present
invention can include multiple rigid members. For example, rigid member 50 can be
located exterior to a first portion of a base pipe and a second rigid member can be
located exterior to a second portion of the base pipe. Filter mediums can be located
between the two rigid members. In some embodiments, rigid member 50 can support
four filter mediums and the second rigid member can support four different filter
mediums. Figure 2 shows an example of a similar arrangement. The second rigid
member can be rotated, for example by forty-five degrees relative to the rigid member
50, to align a receiving portion of the rigid member 50 that with a non-receiving portion
of the second rigid member that has a greater cross-sectional radius. In this
configuration, the filter mediums associated with the rigid member 50 and filter
mediums associated with the second rigid member can be positioned adjacent to each
other in an alternating arrangement.
Illustrative swellable material compositions
[0080] Swellable material according to certain embodiments can be formed from
one or more materials that swell upon contact with an activating fluid. For example, the
swellable material may be a polymer that is capable of swelling to a size that is multiple
times its initial size upon contact with an activating fluid that stimulates the material to
I expand. In some embodiments, the swellable material swells upon contact with an
activating fluid that is a hydrocarbon fluid or a gas. The hydrocarbon fluid is absorbed
by the swellable material and the absorption causes the volume of the swellable
material to increase, thereby expanding radially. The swellable material may expand
the filter mediums and part of the outer surface of the swellable material contacts a
formation face in an open hole completion or a casing wall in a cased wellbore.
[0081] Some embodiments of the swellable material may be made from an
elastic polymer. Examples of elastic polymers include ethylene propylene diene
monomer (EPDM) rubber, styrene butadiene, natural rubber, ethylene propylene
monomer rubber, ethylene vinyl acetate rubber, hydrogenized acrylonitrile butadiene
rubber, acylonitrile butadiene rubber, isoprene rubber, chloroprene rubber and
polynorbornene. The swellable material may also include other materials dissolved in,
or in mechanical mixture, with the other materials that form the swellable material.
Examples of other materials include fibers of cellulose, polyvinyl chloride, methyl
methacrylate, acrylonitrile, ethylacetate, or other polymers.
[0082] In some embodiments, the swellable material is configured to expand
upon contact with an activating fluid that is water. For example, the swellable material
may be a water-swellable polymer such as a water-swellable elastomer or water-
swellable rubber. More specifically, the swellable material may be a water-swellable
hydrophobic polymer or water-swellable hydrophobic copolymer such as a water-
swellable hydrophobic porous copolymer. Other polymers that can be used to fonn the
swellable material include hydrophilic monomers and hydrophobically modified
hydrophilic monomers. Examples of suitable hydrophilic monomers include acrylamide,
2-acrylamido-2methyl propane sulfonic acid, N,N-dimethylacrylamide, vinyl pyrrolidone,
dimethylaminoethyl methacrylate, acrylic acid, trimethylammoniunnethyl, methacrylate
chloride, dimethylaminopropylmethacrylamide, methacrylamide, and hydroxyethyl
acylate.
[0083] A variety of hydrophobically modified hydrophilic monomers can be
utilized in accordance with certain embodiments. Examples of hydophobically modified
hydrophilic monomers include alkyl acrylates, alkyl methacrylates, alkyl acrylamides,
alkyl methacrylamides (where alkyl radicals have from about 4 to about 22 carbon
atoms), alkyl dimethylammoniumethyl methacrylate chloride and alkyl
dimethylammoniumethyl methacrylate iodide (where the alkyl radicals have from about
4 to about 22 carbon atoms), alkyl dimethyiammonium-propyimethacrylamide bromide,
alkyl dimethylammonium propylmethacrylamide chloride and alkyl dimethylammonium-
propylmethacrylamide iodide (where the alkyl groups have from about 4 to about 22
carbon atoms).
[0084] Polymers suitable in swellable material according to certain embodiments
can be prepared by polymerizing any one or more of the hydrophilic monomers with
any one or more of the hydrophobically modified hydrophilic monomers. The
polymerization reaction can be formed in various ways, an example of which is
described in U.S. Patent No. 6,476,169, which is incorporated herein by reference.
These polymers may have estimated molecular weights in the range from about
100,000 to about 10,000,000, with a preferred range of 250,000 to about 3,000,000.
These polymers may also have mole ratios of the hydrophilic monomer(s) to the
hydrophobically modified hydrophilic monomer(s) in the range of from about 99.98:0.02
to about 90:10.
[0085] In some embodiments, the swellable material may be made from a salt
polymer such as polyacrylamide or modified crosslinked poly(meth)acrylate that tends
to attract water from salt water through osmosis. For example, when water that flows
from an area of low salt concentration (the formation water) to an area of high salt
concentration (a salt polymer), across a semi-permeable membrane (an interface
between the salt polymer and production fluids), the salt polymer allows water
molecules to pass, but prevents passage of dissolved salts.
[0086] The foregoing description of the embodiments, including illustrated
embodiments, of the invention has been presented only for the purpose of illustration
and description and is not intended to be exhaustive or to limit the invention to the
precise forms disclosed. Numerous modifications, adaptations, and uses thereof will
be apparent to those skilled in the art without departing from the scope of this invention.
CLAIMS
1. A screen assembly capable of being disposed in a bore, the screen assembly
comprising: a base pipe comprising a sidewall portion having an opening therein; a rigid
member disposed exterior to a first portion of the base pipe, the rigid member
comprising an opening in fluid communication with the opening of the base pipe; a
swellable material disposed exterior to a second portion of the base pipe; and a filter
medium at least partially disposed exterior to the swellable material, the filter medium
being in fluid communication with the opening of the rigid member, wherein, in
response to contact with an activating fluid, the swellable material Is capable of
expanding and displacing at least part of the filter medium toward a surface of the bore.
2. A screen assembly according to claim 1, further comprising: a piston disposed in
the opening of the rigid member and coupled to the base pipe, wherein the piston
comprises a telescoping portion coupled to the filter medium, the radially telescoping
pori:ion being capable of extending from the opening of the rigid member when the
swellable material expands, wherein the filter medium Is capable of filtering fluids and
directing the fluids to an internal flow path of the base pipe through the piston.
3. A screen assembly according to claim 1 or 2, further comprising a material
between the filter medium and the rigid member, the material comprising at least one of
a non-swelling media or a low-swelling media and the material being capable of
providing a temporary seal between the filter medium and the rigid member.
4. A screen assembly according to claim 3, wherein the material comprises rubber.
5. A screen assembly according to any preceding claim, wherein the activating fluid
Is at least one of a hydrocarbon fluid, water, or a gas.
6. A screen assembly capable of being disposed in a bore, the screen assembly
comprising: a base pipe comprising a sidewall portion having a plurality of openings
therein; a rigid member disposed exterior to a first portion of the base pipe, the rigid
member comprising a plurality of openings, each opening of the plurality of openings of
the rigid member being in fluid communication with an opening of the plurality of
openings of the sidewall portion; a swellable material disposed exterior to a second
portion of the base pipe; and a plurality of filter mediums at least partially disposed
exterior to the swellable material, each of the plurality of filter mediums being in fluid
communication with at least one of the plurality of openings of the rigid member,
wherein, in response to contact with an activating fluid, the swellable material is
capable of expanding and displacing at least part of each of the plurality of filter
mediums toward a surface of the bore.
7. A screen assembly according to claim 6, further comprising: a plurality of pistons
comprising a telescoping portion, the plurality of pistons being coupled to the base
pipe, wherein each opening of the plurality of openings of the rigid member has a
piston of the plurality of pistons disposed therein, the telescoping portion being capable
of extending from the rigid member when the swellable material expands.
8. A screen assembly according to claim 6 or 7, wherein the activating fluid is at
least one of a hydrocarbon fluid, water, or a gas.
9. A screen assembly according to claim 6, 7 or 8, wherein each filter medium of
the plurality of filter mediums has a cross-sectional shape of at least one of: a kidney
shape; an oval; a circle; or a rectangle.
10. A screen assembly according to any one of claims 6 to 9, wherein the rigid
member is a ring that is at least one of: a metal; a composite polymer; or a non-swelling
rubber compound.
11. A screen assembly capable of being disposed in a bore, the screen assembly
comprising: a base pipe comprising a sidewall portion having a first plurality of
openings and a second plurality of openings therein, the first plurality of openings being
at a first portion of the base pipe, the second plurality of openings being at a second
portion of the base pipe; a first rigid member disposed exterior to the first portion of the
base pipe; a second rigid member disposed exterior to the second portion of the base
pipe; a swellable material disposed exterior to a third portion of the base pipe; and a
plurality of filter mediums at least partially disposed exterior to the swellable material,
each of the plurality of filter mediums being in fluid communication with at least one
opening of the first plurality of openings or the second plurality of openings, wherein, in
response to contact with an activating fluid, the swellable material is capable of
expanding and displacing at least part of each of the plurality of filter mediums toward a
surface of the bore.
12. A screen assembly according to claim 11, wherein the third portion of the base
pipe is located between the first portion of the base pipe and the second portion of the
base pipe.
13. A screen assembly according to claim 11 or 12, wherein each of the plurality of
filter mediums is in fluid communication with at least one opening of the first plurality of
openings or the second plurality of openings through at least one of a plurality of
openings of the first rigid member or a plurality of openings of the second rigid member.
14. A screen assembly according to claim 11, 12 or 13, wherein each of the first rigid
member and the second rigid member comprise: a first receiving portion for supporting
a first filter medium of the plurality of filter mediums in a running configuration; and a
second receiving portion for supporting a second filter medium of the plurality of filter
mediums in the running configuration.
15. A screen assembly according to claim 14, wherein the first receiving portion and
the second receiving portion define grooves for supporting the first filter medium and
the second filter medium of the plurality of filter mediums in the running configuration.

Screen assemblies capable of being disposed in a bore for hydrocarbon fluid
production are described. The screen assemblies can support filter mediums and
reduce or eliminate plugging by swellable material. One screen assembly includes filter
mediums supported by a rigid member located exterior to a portion of a base pipe. The
rigid member can include openings through which the filter mediums can be in fluid
communication with an inner diameter of the base pipe. Swellable material can be
disposed exterior to a second portion of the base pipe adjacent to the rigid member.
The filter mediums can be displaced to contact a wellbore and the rigid members can
help reduce or prevent plugging of screen assembly openings.