WELLBORE SCREENS AND METHODS OF USE THEREOF
This invention relates to wellbore equipment utilized in conjunction
with operations performed in subterranean wells and, in particular, sand control
screen assemblies that provide secondary flow capabilities.
[0002] During hydrocarbon production from subsurface formations,
efficient control of the movement of unconsolidated formation particles into the
wellbore, such as sand, has always been a pressing concern. Such formation
movement commonly occurs during production from completions in loose sandstone
or following the hydraulic fracture of a formation. Formation movement can also
occur suddenly in the event a section of the wellbore collapses, thereby circulating
significant amounts of particulates and fines within the wellbore. Production of
these unwanted materials may cause numerous problems in the efficient extraction
of oil and gas from subterranean formations. For example, producing formation
particles may tend to plug the formation, tubing, and subsurface flow lines.
Producing formation particles may also result in the erosion of casing, downhole
equipment, and surface equipment. These problems lead to high maintenance
costs and unacceptable well downtime.
[0003] Numerous methods have been utilized to control the movement or
production of these unconsolidated formation particles during production
operations. For example, one or more sand control screen assemblies are
commonly included in the completion string to regulate and restrict the movement
of formation particles. Such sand control screen assemblies are commonly
constructed by installing one or more screen jackets on a perforated base pipe.
The screen jackets typically include one or more drainage layers, one or more
screen elements such as a wire wrapped screen or single or multi layer wire mesh
screen, and a perforated outer shroud. The screens can often incorporate resins
and/or tackifiers that help keep the particulates in position or otherwise not
produced.
[0004] Over time, the screen jackets can become plugged with loose
particulates and fines, generally referred to herein as a filter cake, which can slow
hydrocarbon production or stop production altogether, especially in significantly
plugged locations within the wellbore. To clean the screen assemblies and remove
the filter cake, acids or other solvents can be injected into the wells in order to
remove the filter cake, after which the screen assemblies are often flushed to
ensure proper function once more. The process of cleaning the screen assemblies
is costly, and can require a significant amount of valuable rig time during which
hydrocarbon production is temporarily stopped.
SUMMARY OF THE INVENTION
[0005] This invention relates to wellbore equipment utilized in conjunction
with operations performed in subterranean wells and, in particular, sand control
screen assemblies providing secondary flow capabilities.
[0006] In some embodiments, a sand control screen assembly is disclosed.
The assembly may include a base pipe having an exterior surface and defining one
or more perforations therein; a screen jacket disposed about the exterior surface of
the base pipe and having a primary screen arranged axially adjacent a secondary
screen; and at least one relief valve configured to open upon experiencing a
predetermined fluid pressure, wherein, once opened, the at least one relief valve
diverts fluid flow from the primary screen and provides the fluid flow to the
secondary screen.
[0007] In some embodiments, a method for producing fluids from a
formation is disclosed. The method may include introducing a base pipe into a
wellbore adjacent the formation, the base pipe having a screen jacket disposed
thereabout with a primary screen arranged axially adjacent a secondary screen;
drawing a flow of fluids from the formation and into the base pipe via the primary
screen; opening at least one relief valve when a differential pressure between an
interior of the base pipe and the formation reaches a predetermined pressure
threshold; and diverting the flow of fluids through the at least one relief valve and
to the secondary screen, thereby bypassing the flow of fluids through the primary
screen.
[0008] In other embodiments, other sand control screen assemblies are
disclosed. In one example, the assembly may include a base pipe having an
exterior surface and defining one or more perforations therein; a screen jacket
disposed about the exterior surface of the base pipe and having a primary screen
concentrically disposed about a secondary screen and thereby forming a first
production annulus between the primary and secondary screens; and at least one
relief valve configured to open upon experiencing a predetermined fluid pressure,
wherein, once opened, the at least one relief valve diverts a fluid flow from passing
through both the primary and secondary screens to passing through only the
secondary screen.
[0009] In yet other embodiments, other methods for producing fluids from
a formation are disclosed. An example of a method may include introducing a base
pipe into a wellbore adjacent the formation, the base pipe having a screen jacket
disposed thereabout with a primary screen concentrically disposed about a
secondary screen and thereby forming a first production annulus between the
primary and secondary screens; drawing a flow of fluids from the formation and
into the base pipe via both the primary and secondary screens; opening at least
one relief valve when a differential pressure between the first production annulus
and the formation reaches a predetermined pressure threshold; and diverting the
flow of fluids through the at least one relief valve and to the secondary screen,
thereby bypassing the flow of fluids through the primary screen.
[0010] The features and advantages of the present invention will be
readily apparent to those skilled in the art upon a reading of the description of the
preferred embodiments that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The following figures are included to illustrate certain aspects of the
present invention, and should not be viewed as exclusive embodiments. The
subject matter disclosed is capable of considerable modifications, alterations,
combinations, and equivalents in form and function, as will occur to those skilled in
the art and having the benefit of this disclosure.
[0012] FIG. 1 illustrates a well system that can employ the sand control
screen assemblies described herein.
[0013] FIG. 2 illustrates an exemplary sand control screen assembly,
according to one or more embodiments.
[0014] FIG. 3 illustrates another exemplary sand control screen assembly,
according to one or more embodiments.
[0015] FIG. 4 illustrates another exemplary sand control screen assembly,
according to one or more embodiments.
[0016] FIG. 5 illustrates another exemplary sand control screen assembly,
according to one or more embodiments.
[0017] FIG. 6 illustrates another exemplary sand control screen assembly,
according to one or more embodiments.
DETAILED DESCRIPTION
[0018] This invention relates to wellbore equipment utilized in conjunction
with operations performed in subterranean wells and, in particular, sand control
screen assemblies providing secondary flow capabilities.
[0019] The exemplary sand control screen assemblies disclosed herein
provide an alternate pathway for production fluids to enter the base pipe when a
primary filter media or screen becomes plugged or otherwise ineffectual. When the
primary screen becomes plugged, the formation fluids may be diverted to a
secondary screen which then provides production filtering and continuous flow of
production fluids. Consequently, instead of losing production through a plugged
filter, the embodiments disclosed herein provide a backup system that allows
continual production of fluids into the base pipe, thereby possibly increasing the life
of a producing zone. As will be appreciated by those skilled in the art, this could
prove especially advantageous in the event a portion of the wellbore collapses and
significant amounts of particulates and fines are suddenly circulated within the
wellbore and plug the primary screen. Once the primary screen becomes plugged,
the secondary screen may be activated (e.g., automatically) to allow the flow of
production fluids to continue uninterrupted. Embodiments disclosed herein also
provide sand control screen assemblies that promote self-cleaning of the primary
screen, thereby avoiding the costly and time consuming process of cleaning the
screen assemblies.
[0020] Referring to FIG. 1, illustrated is a well system 100, according to
one or more embodiments of the disclosure. As depicted, the well system 100
includes a wellbore 102 that extends through various earth strata and has a
substantially vertical section 104 extending to a substantially horizontal section
106. The upper portion of the vertical section 104 may have a casing string 108
cemented therein, and the horizontal section 106 may extend through a
hydrocarbon bearing subterranean formation 110. In at least one embodiment, the
horizontal section 106 may be arranged within or otherwise extend through an
open hole section of the wellbore 102.
[0021] A tubing string 112 may be positioned within the wellbore 102 and
extend from the surface. The tubing string 112 provides a conduit for fluids
extracted from the formation 110 to travel to the surface. At its lower end, the
tubing string 112 may be coupled to a completion string 114 arranged within the
horizontal section 106. The completion string 114 serves to divide the completion
interval into various production intervals adjacent the formation 110. As depicted,
the completion string 114 may include a plurality of sand control screen assemblies
116 axially offset from each other along portions of the completion string 114.
Each screen assembly 116 may be positioned between a pair of packers 118 that
provides a fluid seal between the completion string 114 and the wellbore 102,
thereby defining corresponding production intervals. In operation, the screen
assemblies 116 serve the primary function of filtering particulate matter out of the
production fluid stream such that the particulates and other fines are not produced
to the surface.
[0022] It should be noted that even though FIG. 1 depicts the screen
assemblies 116 as being arranged in an open hole portion of the wellbore 102,
embodiments are contemplated herein where one or more of the screen assemblies
116 is arranged within cased portions of the wellbore 102. Also, even though FIG.
1 depicts a single screen assembly 116 arranged in each production interval, it will
be appreciated by those skilled in the art that any number of screen assemblies 116
may be deployed within a particular production interval without departing from the
scope of the disclosure. In addition, even though FIG. 1 depicts multiple production
intervals separated by the packers 118, it will be understood by those skilled in the
art that the completion interval may include any number of production intervals
with a corresponding number of packers 118 arranged therein. In other
embodiments, the packers 118 may be entirely omitted from the completion
interval, without departing from the scope of the disclosure.
[0023] Further, even though FIG. 1 depicts the screen assemblies 116 as
being arranged in a generally horizontal section 106 of the wellbore 102, those
skilled in the art will readily recognize that the screen assemblies 116 are equally
well suited for use in wells having other directional configurations including vertical
wells, deviated wellbores, slanted wells, multilateral wells, combinations thereof,
and the like. Accordingly, the use of directional terms such as above, below, upper,
lower, upward, downward, left, right, uphole, downhole and the like are used in
relation to the illustrative embodiments as they are depicted in the figures, the
upward direction being toward the top of the corresponding figure and the
downward direction being toward the bottom of the corresponding figure, the
uphole direction being toward the surface of the well and the downhole direction
being toward the toe of the well.
[0024] Referring now to FIG. 2, illustrated is an exemplary sand control
screen assembly 200, according to one or more embodiments. Along with the other
screen assemblies described in greater detail below, the sand control screen
assembly 200 may replace the screen assembly 116 described in FIG. 1 and
otherwise be used in the exemplary well system 100 depicted therein. The screen
assembly 200 may include a base pipe 202 that defines one or more openings or
perforations 204 configured to provide fluid communication between the interior
203 of the base pipe and the formation 110. The screen assembly 200 may further
include a screen jacket 206 that is attached or otherwise coupled to the exterior of
the base pipe 202. In operation, the screen jacket 206 may serve as a filter
medium designed to allow fluids derived from the formation 110 to flow
therethrough but prevent the influx of particulate matter of a predetermined size.
[0025] In some embodiments, the screen jacket 206 includes a first
connector ring 208a arranged about the base pipe 202 at the uphole end of the
screen jacket 206 and a second connector ring 208b arranged about the base pipe
202 at the downhole end of the screen jacket 206. The first and second connector
rings 208a, b provide a mechanical interface between the base pipe 202 and the
opposing ends of the screen jacket 206. Each connector ring 208a,b may be
formed from a metal such as 13 chrome, 304L stainless steel, 316L stainless steel,
420 stainless steel, 410 stainless steel, Incoloy 825, or similar alloys. Moreover,
each connector ring 208a, b may be coupled or otherwise attached to the outer
surface of base pipe 202 by being welded, brazed, threaded, combinations thereof,
or the like. In other embodiments, however, one or more of the connector rings
208a,b may be an integral part of the screen jacket 206, and not a separate
component thereof.
[0026] The screen jacket 206 may further include one or more screens
arranged about the base pipe 202, for example, a primary screen 210a and a
secondary screen 210b. Each of the primary and secondary screens 210a,b may be
characterized as a filter medium designed to allow fluids to flow therethrough but
prevent the influx of particulate matter of a predetermined size. In some
embodiments, the primary and secondary screens 210a,b may be fluid-porous,
particulate restricting devices made from of a plurality of layers of a wire mesh that
are diffusion bonded or sintered together to form a fluid porous wire mesh screen.
In other embodiments, however, the screens 210a, b may have multiple layers of a
weave mesh wire material having a uniform pore structure and a controlled pore
size that is determined based upon the properties of the formation 110. For
example, suitable weave mesh screens may include, but are not limited to, a plain
Dutch weave, a twilled Dutch weave, a reverse Dutch weave, combinations thereof,
or the like. Those skilled in the art will readily recognize that several other mesh
designs are equally suitable, without departing from the scope of the disclosure. In
other embodiments, however, the primary and secondary screens 210a,b may
include a single layer of wire mesh, multiple layers of wire mesh that are not
bonded together, a single layer of wire wrap, multiple layers of wire wrap or the
like, that may or may not operate with a drainage layer.
[0027] As illustrated, the primary screen 210a may be axially adjacent the
secondary screen 210b and radially offset a short distance from the base pipe 202.
The primary screen 210a may be coupled or otherwise attached to the first
connector ring 208a at its uphole end and the secondary screen 210b may be
coupled or otherwise attached to the second connector ring 208b at its dowhole
end. In one or more embodiments, however, the first and second connector rings
208a, b may be omitted from the screen assembly 200 and the primary screen 210a
may be coupled directly to the base pipe 202 at its uphole end and the secondary
screen 210b may be coupled directly to the base pipe 202 at its dowhole end.
[0028] In at least one embodiment, the primary and secondary screens
210a,b may be coupled to and/or otherwise separated by a screen isolator 212. In
other embodiments, however, the primary and secondary screens 210a,b may be
contiguous lengths and otherwise disposed over the top of the screen isolator 212.
In any event, the screen isolator 212 may be configured to support the primary and
secondary screens 210a,b in a radially-offset relationship with the base pipe 202 so
as to define a first production annulus 214a and a second production annulus 214b
between the base pipe 202 and the primary and secondary screens 210a,b,
respectively.
[0029] The screen isolator 212 may be arranged about the base pipe 202
and coupled thereto. As illustrated, the screen isolator 212 may include a relief
valve 216 disposed therein and configured to provide fluid communication between
the first and second production annuli 214a,b. In some embodiments, the relief
valve 216 may be a rupture disc, a check valve, or any other flow regulating device
configured to open upon experiencing a predetermined fluid pressure. In other
embodiments, the relief valve 216 may be a mechanical valve configured to actuate
to an open position upon being triggered once the predetermined pressure is
sensed. Once the predetermined pressure is reached, the relief valve 216 may be
configured to open and provide fluid communication between the first and second
annuli 214a,b.
[0030] The screen assembly 200 may also include a flow regulator 218
arranged within or substantially adjacent the first connector ring 208a. In
operation, the flow regulator 218 may be configured to regulate fluid flow to the
one or more perforations 204 in the base pipe 202 from the first and second
production annuli 214a,b. In one embodiment, the flow regulator 218 is an inflow
control device, as known by those skilled in the art. In other embodiments,
however, the flow regulator 218 may simply define a hole therein which serves to
restrict flow to the interior 203 of the base pipe 202 via the one or more
perforations 204. In yet other embodiments, the flow regulator 218 may be
omitted altogether from the screen assembly 200, without departing from the scope
of the disclosure.
[0031] In operation, the sand control screen assembly 200 may be
configured to initially draw in fluids from the formation 110 via the primary screen
210a. As indicated by the arrows, the fluid may flow into the first production
annulus 214a, pass through the flow regulator 218 and the one or more
perforations 204, and eventually flow into the interior 203 of the base pipe 202 for
production to the surface. Over time, however, the primary screen 210a may
become plugged with particulates and/or other fines circulating within the fluids
derived from the formation 110, thereby restricting fluid flow into the first
production annulus 214a via the primary screen 210a. As the primary screen 210a
becomes more and more plugged with particulate matter, a differential pressure
between the first annulus 214a {e.g., the interior 203 of the base pipe 202) and the
formation 110 is created and correspondingly increases. This differential pressure
is also experienced across the relief valve 216, since the second production annulus
214b remains at essentially at the same pressure as the formation 110 until the
relief valve 216 is opened.
[0032] Eventually, the differential pressure across the relief valve 216 will
reach a predetermined pressure threshold, thereby causing the relief valve 216 to
be opened or otherwise actuated to enable fluid flow therethrough. For example, in
embodiments where the relief valve 216 is a rupture disc, the rupture disc is
designed to rupture or otherwise be perforated once the differential pressure
reaches the predetermined pressure threshold. Similarly, in embodiments where
the relief valve 216 is mechanically-actuated, an actuator or the like may be
triggered to open the relief valve 216 once the predetermined pressure threshold is
sensed. With the relief valve 216 opened, fluid from the formation 110 may then
commence to flow through the secondary screen 210b and into the second
production annulus 214b which feeds the fluid into the first production annulus
214a via the relief valve 216. As the fluid flows through the secondary screen
210b, it is filtered as it would have been through the primary screen 210a.
Consequently, the secondary screen 210b may serve as a back up to the primary
screen 210a by providing formation fluid to the interior 203 of the base pipe 202
when the primary screen 210a becomes plugged or otherwise ineffective. As a
result, a continuous and uninterrupted flow of formation fluid is provided to the
surface.
[0033] As can be appreciated, the relief valve 216 can be designed to
withstand varying differential pressures. Accordingly, the relief valve 216 may be
configured or otherwise designed to open at different predetermined pressure
thresholds. Since pressures in the subterranean formation 110 may vary from
wellbore to wellbore, the predetermined pressure threshold fro each relief valve 216
may likewise vary. This may prove advantageous in intelligently designing
completion strings 114 (FIG. 1) with specialized relief valves 216 that may be
selectively designed to open at particularized predetermined pressure thresholds
known to correspond with the particular formation 110, thus ensuring a constant
flow of formation fluids to the surface.
[0034] Referring now to FIG. 3, illustrated is another exemplary sand
control screen assembly 300, according to one or more embodiments disclosed.
The screen assembly 300 may be similar in some respects to the screen assembly
200 of FIG. 2. Accordingly, the screen assembly 300 may be best understood with
reference to FIG. 2, wherein like numerals indicate like elements that will not be
described again in detail. As illustrated, the screen jacket 206 may again include
the primary and secondary screens 210a,b arranged about the base pipe 202 and
axially offset from each other. Moreover, the screen jacket 206 again includes the
first connector ring 208a arranged about the base pipe 202 at the uphole end of the
screen jacket 206 and the second connector ring 208b arranged about the base
pipe 202 at the downhole end of the screen jacket 206.
[0035] The second connector ring 208b, however, may further include a
shroud 304 extending axially from the connector ring 208b and a screen isolator
306 extending radially from the shroud 304 and being coupled to or otherwise in
biasing engagement with the base pipe 202. The combination of the second
connector ring 208b, the shroud 304, and the screen isolator 306 may define a
production annulus 308. The secondary screen 210b may be arranged within the
production annulus 308 and therefore substantially isolated from the formation 110.
[0036] The screen isolator 306 may generally interpose the primary and
secondary screens 210a,b. In one or more embodiments, the screen isolator 306
may have one or more relief valves 216 (one shown) disposed therein and
configured to provide fluid communication between the formation 110 and the
secondary screen 210b when opened. Likewise, in one or more embodiments, the
shroud 304 may include one or more relief valves 216 (two shown) arranged
therein and also configured to provide fluid communication between the formation
110 and the secondary screen 210b when opened.
[0037] In operation, the sand control screen assembly 300 may initially
draw fluids from the formation 110 and into the interior 203 of the base pipe 202
via the primary screen 210a; the primary screen 210a being bounded at its uphole
end with a first connector ring 208a. Over time, the primary screen 210a may
become plugged with particulates, thereby restricting fluid flow into the base pipe
202 via the one or more perforations 204 defined in the base pipe 202 radially
adjacent the primary screen 210a. Restricting the fluid flow through the primary
screen 210a may generate a differential pressure between the interior 203 of the
base pipe 202 and the formation 110. Likewise, since the production annulus 308
is essentially at the same pressure as the interior 203 of the base pipe 202, this
same differential pressure will also be experienced across the one or more relief
valves 216 arranged within the shroud 304 and/or the screen isolator 306.
[0038] As the primary screen 210a becomes increasingly plugged, the
differential pressure across the relief valves 216 correspondingly increases until
reaching the predetermined pressure threshold of the relief valves 216, at which
point one or all of the relief valves 216 may be configured to be opened or
otherwise actuated to enable fluid flow therethrough. With the relief valve(s) 216
opened, fluid from the formation 110 may then commence to flow through the
secondary screen 210b and into the interior 203 of the base pipe 202 via the one or
more perforations 204 defined in the base pipe 202 radially adjacent the secondary
screen 210a. Consequently, the secondary screen 210b may again serve as a back
up to the primary screen 210a in providing formation 110 fluid to the interior 203 of
the base pipe 202 when the primary screen 210a becomes plugged or otherwise
ineffective. Moreover, fluid may flow into the production annulus 308 either radially
and/or axially since the relief valves 216 may be arranged in either the shroud 304
or the screen isolator 306, or both. As a result, a continuous and uninterrupted
flow of formation fluid is again provided to the surface.
[0039] While FIG. 3 depicts three relief valves 216 disposed within the
shroud 304 and/or the screen isolator 306, those skilled in the art will readily
recognize that more or less than three relief valves 216 may be employed without
departing from the scope of the disclosure. The number of relief valves 216 may
depend, in at least one embodiment, on desired flow rates. Moreover, while FIG. 3
depicts the sand control screen assembly 300 as extending along a portion of an
individual base pipe 202, it will be appreciated that the screen assembly 300, or
any of the screen assemblies generally described herein, may be configured to
extend across portions of two or more individual base pipes, such as by straddling
base pipe connection points.
[0040] Referring now to FIG. 4, illustrated is another exemplary sand
control screen assembly 400, according to one or more embodiments disclosed.
The screen assembly 400 may be similar in some respects to the screen assembly
200 of FIG. 2 and therefore may be best understood with reference thereto, where
like numerals will indicate like elements not described again. Similar to the screen
assembly 200 of FIG. 2, the screen assembly 400 may have primary and secondary
screen assemblies 210a,b arranged about the base pipe 202; the base pipe 202
defining the one or more perforations 204 therein. Unlike the screen assembly 200
of FIG. 2, however, the primary and secondary screen assemblies 210a, b in the
screen assembly 400 may be concentrically disposed about the base pipe 202.
[0041] Specifically, the secondary screen 210a may be arranged adjacent
the base pipe 202 and the primary screen 210b may be radially offset a short
distance from the secondary screen 210b such that a concentric relationship is
generated between the two screens 210a, b and a first production annulus 402a is
defined therebetween. Moreover, the first and second connector rings 208a,b may
again axially bound the primary and secondary screen assemblies 210a, b, however,
the first connector ring 208a may be configured to be coupled to both the primary
and secondary screens 210a,b on their respective uphole ends, and the second
connector ring 208b may be configured to be coupled to both the primary and
secondary screens 210a,b on their respective downhole ends.
[0042] The second connector ring 208b may include a shroud 402
extending axially from the connector ring 208b and a valve housing 404 extending
radially from the shroud 404 and being coupled to or otherwise in biasing
engagement with the base pipe 202. The combination of the second connector ring
208b, the shroud 402, and the valve housing 404 may define a second production
annulus 402b. The shroud 404 may define one or more holes 408 therein, and the
one or more holes 408 may provide fluid communication between the formation
110 and the second production annulus 402b. In one embodiment, the
corresponding downhole ends of the primary and secondary screens 210a,b may be
coupled to the valve housing 406 and shroud 404, respectively. The valve housing
406 may have a relief valve 216 arranged or otherwise disposed therein. When
opened, the relief valve 216 may be configured to provide fluid communication
between the first and second production annuli 402a,b.
[0043] In operation, because of the concentric arrangement of the primary
and secondary screens 210a, b, the sand control screen assembly 400 may initially
draw in fluids from the formation 110 and into the interior 203 of the base pipe 202
via both the primary screen 210a and the secondary screen 210b. In particular,
the primary screen 210a may be configured to substantially filter the incoming
fluids derived from the formation 110 and feed the filtered fluids into the first
production annulus 402a and to the secondary screen 210b. The secondary screen
210b may be configured to convey the filtered fluids to the interior 203 of the base
pipe 202 via the one or more perforations 204 defined radially adjacent thereto in
the base pipe 202. Over time, however, the primary screen 210a may become
plugged with particulates, thereby restricting fluid flow into first production annulus
402a and generating a differential pressure between the first production annulus
402a (e.g., the interior 203 of the base pipe 202) and the formation 110. Since the
second production annulus 402b is essentially at the same pressure as the
formation 110 via the one or more holes 408, this same differential pressure may
also be experienced across the relief valve 216 arranged within the valve housing
406.
[0044] As the primary screen 210a becomes increasingly plugged, the
differential pressure across the relief valve 216 correspondingly increases until
reaching its predetermined pressure threshold, at which point the relief valve 216
may be configured to be opened or otherwise actuated to enable fluid flow
therethrough. With the relief valve 216 opened, fluid from the formation 110 may
then commence to flow through the one or more holes 408 and into the second
production annulus 402b which feeds the incoming fluid into the first production
annulus 214a via the relief valve 216. Accordingly, the relief valve 216 allows the
fluid from the formation 110 to bypass a plugged primary screen 210a and
commence filtration of the formation fluids using the secondary screen 210b, which
continues to feed the filtered fluids to the interior 203 of the base pipe 202 via the
one or more perforations 204. As such, the secondary screen 210b may again
serve as a back up to the primary screen 210a in providing formation fluid to the
interior 203 of the base pipe 202 when the primary screen 210a becomes plugged
or otherwise ineffective.
[0045] In one or more embodiments, the sand control screen assembly
400 may further include one or more sensors configured to sense the differential
pressure between the first production annulus 402a and the formation 110 and
trigger the actuation of the relief valve 216 when the predetermined pressure
threshold is reached. Specifically, a first sensor 410a may be arranged on the
exterior of the assembly 400, such as by being coupled to the outer surface of the
shroud 404 or the like. The first sensor 410a may be configured to measure the
pressure of the fluids within the formation 110 and report real-time pressure
measurements to a computing device 414 communicably coupled thereto. A
second sensor 410b may be arranged within the first production annulus 402a and
configured to measure the pressure in the first production annulus 402a and report
the same to the computing device 414 also communicably coupled thereto.
[0046] The computing device 414 may be a computer including a
processor configured to execute one or more sequences of instructions or code
stored on a non-transitory, computer-readable medium. The processor can be, for
example, a general purpose microprocessor, a microcontroller, a digital signal
processor, an artificial neural network, or any like suitable entity that can perform
calculations or other manipulations of data. In some embodiments, the computing
device 414 may further include a memory or any other suitable storage device or
medium.
[0047] The computing device 414 may be configured to receive the
pressure measurements derived from both the first and second sensors 410a,b and
calculate the pressure differential existing between the first production annulus
402a and the formation 110, which, as will be appreciated, is the same pressure
differential experienced across the relief valve 216 arranged within the valve
housing 406. Once the measured pressure differential reaches a predetermined
pressure threshold as recognized by the computing device 414, the computing
device 414 may be configured to trigger the opening of the relief valve 216. For
example, in embodiments where the relief valve 216 is mechanically, electrically, or
hydraulically actuated, an actuator or the like may be triggered by the computing
device 414 to open the relief valve 216 once the predetermined pressure threshold
is sensed.
[0048] In some embodiments, the computing device 414 is omitted and
instead the first and second sensors 410a,b may be configured to communicate an
alert signal, either wired or wirelessly, to a user at the surface. The alert signal
may warn the user that the predetermined pressure threshold has been reached in
the screen assembly 400 and prompt the user to manually manipulate the relief
valve 216 from the surface, such as through remote controlled actuating devices or
the like. As a result, the user may be actively involved in diverting the flow of
fluids through the relief valve 216 and away from the primary screen 210a when
the primary screen 210a is determined to be plugged or otherwise ineffectual.
[0049] In one or more embodiments, the relief valve 216 may be sized or
otherwise actuated by the computing device 414 such that the influx of formation
fluids into the first production annulus 402a therethrough will not only be produced
through the secondary screen 210b, but also a portion thereof may be flow through
the primary screen 210a in reverse. In other words, the influx of fluids through the
relief valve 216 may increase the pressure within the first production annulus 402a
such that a portion of the incoming fluids through the relief valve 216 is conveyed
in reverse through the primary screen 210a and may thereby serve to remove
built-up filter cake from the outer surface of the primary screen 210a in the
process.
[0050] Removing the filter cake from the exterior of the primary screen
210a will allow more fluid to pass therethrough and thereby serve to reduce the
pressure within the first production annulus 402a. In one or more embodiments,
once the second sensor 410b measures a reduced pressure in the first production
annulus 402a, which may be indicative of a cleansed primary screen 210a, the
computing device 414 may be configured to trigger the relief valve 216 to close and
thereby resume production of fluids through both the primary and secondary
screens 210a,b. Those skilled in the art will readily recognize that the computing
device 414 and corresponding sensors 410a,b may be employed in any of the
embodiments disclosed herein, without departing from the scope of the disclosure.
Moreover, the computing device 414 and corresponding sensors 410a,b may be
remotely operated from the surface, for example.
[0051] Referring now to FIG. 5, illustrated is another exemplary sand
control screen assembly 500, according to one or more embodiments disclosed.
The screen assembly 500 may be similar in some respects to the screen assembly
400 of FIG. 4 and therefore may be best understood with reference thereto, where
like numerals will indicate like elements not described again. Similar to the screen
assembly 400 of FIG. 4, the screen assembly 500 may have primary and secondary
screen assemblies 210a,b concentrically disposed about the base pipe 202 and
bounded at each end with the first and second connector rings 208a,b. Specifically,
the secondary screen 210a may be arranged adjacent the base pipe 202 and the
primary screen 210b may be radially offset a short distance from the secondary
screen 210b such that a concentric relationship is generated between the two
screens 210a,b and a production annulus 502 is defined therebetween.
[0052] In one or more embodiments, one or both of the first and second
connector rings 208a,b may have a relief valve 216 arranged or otherwise disposed
therein. When opened, the relief valve(s) 216 may be configured to provide fluid
communication between the formation 110 and the production annulus 502, and
thereby bypass the primary screen 210a. In some embodiments, one or more relief
valves 216 may also be arranged in or otherwise form part of the primary screen
210a. In at least one embodiment, one or more of the relief valves 216 arranged in
the primary screen 210a may be low pressure burst discs, for example.
[0053] In operation, the sand control screen assembly 500 may initially
draw in fluids from the formation 110 and into the interior 203 of the base pipe 202
via both the primary screen 210a and the secondary screen 210b. In particular,
the primary screen 210a may be configured to substantially filter the incoming
fluids derived from the formation 110 and feed the filtered fluids into the production
annulus 502 and to the secondary screen 210b. The secondary screen 210b may
be configured to convey the filtered fluids to the interior 203 of the base pipe 202
via the one or more perforations 204 radially adjacent thereto and defined in the
base pipe 202.
[0054] Over time, however, the primary screen 210a may become plugged
with particulates from the formation 110, thereby restricting fluid flow into the
production annulus 502 and generating a differential pressure between the
production annulus 502 {e.g., the interior 203 of the base pipe 202) and the
formation 110. As the primary screen 210a becomes increasingly plugged, the
differential pressure across the various relief valves 216 may correspondingly
increase until reaching a predetermined pressure threshold, at which point one or
more of the relief valves 216 may be configured to be opened or otherwise actuated
to enable fluid flow therethrough. With the relief valve(s) 216 opened, fluid from
the formation 110 may then be generally diverted around the primary screen 210a
and flow into the production annulus 502 via the relief valve(s) 216. Consequently,
filtration of the incoming fluids may then be undertaken using the secondary screen
210b which continues to feed the filtered fluids to the interior 203 of the base pipe
202 via the one or more perforations 204.
[0055] Referring now to FIG. 6, illustrated is yet another exemplary sand
control screen assembly 600, according to one or more embodiments disclosed.
The screen assembly 600 may be similar in some respects to the screen assemblies
400 and 500 of FIGS. 4 and 5, respectively, and therefore may be best understood
with reference thereto, where like numerals will indicate like elements not described
again. Similar to the screen assembly 500 of FIG. 5, the screen assembly 600 may
have primary and secondary screen assemblies 210a, b concentrically disposed
about the base pipe 202. Specifically, the secondary screen 210a may be arranged
adjacent the base pipe 202 and bounded at each end with the first and second
connector rings 208a, b. Moreover, the primary screen 210b may be radially offset
a short distance from the secondary screen 210b such that a concentric relationship
is generated between the two screens 210a,b and a production annulus 602 is
defined therebetween.
[0056] In one embodiment, as illustrated, the second connector ring 208b
may have a relief valve 216 arranged or otherwise disposed therein. As can be
appreciated, however, the first connector ring 208a may alternatively have the
relief valve 216 arranged therein, or both the first and second connector rings
208a,b may have respective relief valves 216 arranged therein. When opened, the
relief valve 216 may be configured to provide fluid communication between the
formation 110 and the production annulus 602, and thereby bypass the primary
screen 210a in the event the primary screen 210a becomes plugged or otherwise
ineffectual.
[0057] In operation, the sand control screen assembly 600 may initially
draw in fluids from the formation 110 and into the interior 203 of the base pipe 202
via both the primary screen 210a and the secondary screen 210b. In particular,
the primary screen 210a may be configured to substantially filter the incoming
fluids derived from the formation 110 and feed the filtered fluids into the production
annulus 602 and to the secondary screen 210b. The secondary screen 210b may
be configured to convey the filtered fluids to the interior 203 of the base pipe 202
via the one or more perforations 204. Over time, however, the primary screen
210a may become plugged with particulates, thereby restricting fluid flow into the
production annulus 602 and generating a differential pressure between the
production annulus 602 (e.g., the interior 203 of the base pipe 202) and the
formation 110.
[0058] As the primary screen 210a becomes increasingly plugged, the
differential pressure across the relief valve 216 correspondingly increases until
reaching a predetermined pressure threshold, at which point the relief valve 216
may be configured to open to enable fluid flow therethrough. With the relief valve
216 opened, fluid from the formation 110 may then be diverted around the plugged
primary screen 210a and flow into the production annulus 602 via the relief valve
216. Filtration of the incoming fluids may then be accomplished using the
secondary screen 210b which continues to feed the filtered fluids to the interior 203
of the base pipe 202 and thereby provide a continuous and uninterrupted flow of
formation fluid to the surface.
[0059] In one or more embodiments, the relief valve 216 may be sized or
otherwise designed such that the influx of the formation fluids into the production
annulus 602 will not only be produced through the secondary screen 210b, but also
a portion thereof may be conveyed through the primary screen 210a in reverse in
order to help unplug the primary screen 210a. In other words, the influx of fluids
through the relief valve 216 may serve to increase the pressure within the first
production annulus 402a such that a portion of the incoming fluid through the relief
valve 216 is conveyed in reverse through the primary screen 210a and may thereby
remove a portion of the built-up filter cake in the process.
[0060] Removing the filter cake from the exterior of the primary screen
210a will allow more fluid to pass therethrough and thereby serve to reduce the
pressure within the production annulus 602. As the pressure within the production
annulus 602 decreases, the differential pressure across the relief valve 216
correspondingly decreases. In one or more embodiments, the relief valve 216 may
be configured to close once the differential pressure descends again below the
predetermined pressure threshold. For example, the relief valve 216 may be a
flapper valve, or the like, and configured to open and close upon interaction with
predetermined pressures. With the relief valve 216 once again in its closed
position, production of fluids may again be accomplished through the concentrically
arranged primary and secondary screens 210a, b.
[0061] Therefore, the present invention is well adapted to attain the ends
and advantages mentioned as well as those that are inherent therein. The
particular embodiments disclosed above are illustrative only, as the present
invention may be modified and practiced in different but equivalent manners
apparent to those skilled in the art having the benefit of the teachings herein.
Furthermore, no limitations are intended to the details of construction or design
herein shown, other than as described in the claims below. It is therefore evident
that the particular illustrative embodiments disclosed above may be altered,
combined, or modified and all such variations are considered within the scope and
spirit of the present invention. The invention illustratively disclosed herein suitably
may be practiced in the absence of any element that is not specifically disclosed
herein and/or any optional element disclosed herein. While compositions and
methods are described in terms of "comprising," "containing," or "including" various
components or steps, the compositions and methods can also "consist essentially
of" or "consist of" the various components and steps. All numbers and ranges
disclosed above may vary by some amount. Whenever a numerical range with a
lower limit and an upper limit is disclosed, any number and any included range
falling within the range is specifically disclosed. In particular, every range of values
(of the form, "from about a to about b," or, equivalently, "from approximately a to
b," or, equivalently, "from approximately a-b" disclosed herein is to be understood
to set forth every number and range encompassed within the broader range of
values. Also, the terms in the claims have their plain, ordinary meaning unless
otherwise explicitly and clearly defined by the patentee. Moreover, the indefinite
articles "a" or "an," as used in the claims, are defined herein to mean one or more
than one of the element that it introduces. If there is any conflict in the usages of a
word or term in this specification and one or more patent or other documents that
may be incorporated herein by reference, the definitions that are consistent with
this specification should be adopted.

CLAIMS
The invention claimed is:
1. Asand control screen assembly, comprising:
a base pipe having an exterior surface and defining one or more perforations
therein;
a screen jacket disposed about the exterior surface of the base pipe and
having a primary screen arranged axially adjacent a secondary screen;
and
at least one relief valve configured to open upon experiencing a
predetermined fluid pressure, wherein, once opened, the at least one
relief valve diverts fluid flow from the primary screen and provides the
fluid flow to the secondary screen.
2. The sand control screen assembly of claim 1, wherein the at least one
relief valve is arranged within a screen isolator disposed about the base pipe and
configured to at least partially support the primary and secondary screens.
3. The sand control screen assembly of claim 2, wherein a first
production annulus is defined between the base pipe and the primary screen and a
second production annulus is defined between the base pipe and the secondary
screen, and the at least one relief valve provides fluid communication between the
first and second production annuli.
4. The sand control screen assembly of claim 3, further comprising:
first and second connector rings forming a mechanical interface between the
base pipe and opposing ends of the screen jacket; and
a flow regulator arranged within the first connector ring and configured to
regulate fluid flow to the one or more perforations in the base pipe
from the first and second production annuli.
5. The sand control screen assembly of claim 1, further comprising first
and second connector rings forming a mechanical interface between the base pipe
and opposing ends of the screen jacket, the second connector ring including a
shroud extending axially from the second connector ring and a screen isolator
extending radially from the shroud and engaging the base pipe, wherein the second
connector ring, shroud, and screen isolator cooperatively define a production
annulus in which the secondary screen is arranged.
6. The sand control screen assembly of claim 5, wherein the at least one
relief valve is arranged in the screen isolator.
7. The sand control screen assembly of claim 5, wherein the at least one
relief valve is arranged in the shroud.
8. The sand control screen assembly of claim 1, wherein the at least one
relief valve is one of a rupture disc or a check valve.
9. The sand control screen assembly of claim 1, wherein the at least one
relief valve is mechanically-actuated.
10. A method for producing fluids from a formation, comprising:
introducing a base pipe into a wellbore adjacent the formation, the base pipe
having a screen jacket disposed thereabout with a primary screen
arranged axially adjacent to a secondary screen;
drawing a flow of fluids from the formation and into the base pipe via the
primary screen;
opening at least one relief valve when a differential pressure between an
interior of the base pipe and the formation reaches a predetermined
pressure threshold; and
diverting the flow of fluids through the at least one relief valve and to the
secondary screen, thereby bypassing the flow of fluids through the
primary screen.
11. The method of claim 10, wherein drawing the flow of fluids from the
formation and into the base pipe via the primary screen further comprises trapping
particulates from the formation in the primary screen and thereby increasing the
differential pressure.
12. The method of claim 10, further comprising at least partially
supporting the primary and secondary screens with a screen isolator disposed about
the base pipe, wherein the at least one relief valve is arranged within the screen
isolator.
13. The method of claim 12, wherein diverting the flow of fluids from the
primary screen to the secondary screen further comprises providing fluid
communication through the at least one relief valve from a second production
annulus defined between the base pipe and the secondary screen and a first
production annulus defined between the base pipe and the primary screen.
14. The method of claim 13, wherein the base pipe further includes first
and second connector rings forming a mechanical interface between the base pipe
and opposing ends of the screen jacket, the method further comprising regulating
the flow of fluids into the base pipe with a flow regulator arranged within the first
connector ring.
15. A sand control screen assembly, comprising:
a base pipe having an exterior surface and defining one or more perforations
therein;
a screen jacket disposed about the exterior surface of the base pipe and
having a primary screen concentrically disposed about a secondary
screen and thereby forming a first production annulus between the
primary and secondary screens; and
at least one relief valve configured to open upon experiencing a
predetermined fluid pressure, wherein, once opened, the at least one
relief valve diverts a fluid flow from passing through both the primary
and secondary screens to passing through only the secondary screen.
16. The sand control screen assembly of claim 15, further comprising first
and second connector rings forming a mechanical interface between the base pipe
and opposing ends of the screen jacket.
17. The sand control screen assembly of claim 16, wherein the second
connector ring includes a shroud extending axially from the connector ring and a
valve housing extending radially from the shroud and engaging the base pipe, the
combination of the second connector ring, shroud, and valve housing defining a
second production annulus and the shroud defines one or more holes configured to
provide fluid communication between the second production annulus and an
external environment.
18. The sand control screen assembly of claim 17, wherein the at least one
relief valve is arranged within the valve housing and when opened provides fluid
communication between the first and second production annuli.
19. The sand control screen assembly of claim 17, further comprising:
a first sensor arranged to measure a fluid pressure in the external
environment;
a second sensor arranged to measure a fluid pressure in the first production
annulus; and
a computing device communicably coupled to both the first and second
sensors and configured calculate a differential pressure between the
external environment and the first production annulus, wherein, when
the differential pressure reaches a predetermined pressure threshold,
the computing device actuates and opens the at least one valve.
20. The sand control screen assembly of claim 16, wherein the at least one
relief valve is arranged in one or both of the first and second connector rings.
21. The sand control screen assembly of claim 20, wherein the at least one
relief valve is a flapper valve.
22. The sand control screen assembly of claim 15, wherein the at least one
relief valve is arranged in the primary screen.
23. The sand control screen assembly of claim 22, wherein the at least
one relief valve is a low pressure burst disc.
24. The sand control screen assembly of claim 15, wherein the at least one
relief valve is one of a rupture disc or a check valve.
25. The sand control screen assembly of claim 15, wherein the at least one
relief valve is mechanically-actuated.
26. A method for producing fluids from a formation, comprising:
introducing a base pipe into a wellbore adjacent the formation, the base pipe
having a screen jacket disposed thereabout with a primary screen
concentrically disposed about a secondary screen and thereby forming
a first production annulus between the primary and secondary
screens;
drawing a flow of fluids from the formation and into the base pipe via both
the primary and secondary screens;
opening at least one relief valve when a differential pressure between the
first production annulus and the formation reaches a predetermined
pressure threshold; and
diverting the flow of fluids through the at least one relief valve and to the
secondary screen, thereby bypassing the flow of fluids through the
primary screen.
27. The method of claim 26, wherein drawing the flow of fluids from the
formation and into the base pipe via both the primary and secondary screens
further comprises trapping particulates from the formation in the primary screen
and thereby increasing the differential pressure.
28. The method of claim 26, wherein the base pipe further includes first
and second connector rings forming a mechanical interface between the base pipe
and opposing ends of the screen jacket, and wherein diverting the flow of fluids
through the at least one relief valve further comprises drawing the flow of fluids
into a second production annulus defined by the second connector ring, the first
and second production annuli being in fluid communication through the at least one
relief valve.
29. The method of claim 26, further comprising:
sensing a fluid pressure in the formation with a first sensor;
sensing a fluid pressure in the first production annulus with a second sensor;
calculating a differential pressure between the external environment and the
first production annulus with a computing device communicably
coupled to both the first and second sensors; and
triggering the at least one relief valve to open with the computing device
when the differential pressure reaches a predetermined pressure
threshold as calculated by the computing device.
30. The method of claim 26, wherein opening at least one relief valve
further comprises increasing a fluid pressure in the first production annulus such
that a portion of the flow of fluids diverted through the at least one relief valve is
forced through the primary screen.