FIELD OF INVENTION
The present invention relates to apparatus, systems and methods for a flow
control device. The present invention relates generally to equipment utilized and
operations performed in conjunction with a subterranean well and, more particularly,
5 to the application of flow control devices to manage fluid flow into and out of a
tubular body.
BACKGROUND TECHNICAL INFORMATION
Without limiting the scope of the disclosure, its background will be described
with reference to producing fluid from a hydrocarbon bearing subterranean formation,
10 as an example.
During the production of hydrocarbons from a subterranean well, it is
desirable to substantially reduce or exclude the production of water produced from the
well. For example, it may be desirable for the fluid produced from the well to have a
relatively high proportion of hydrocarbons, and a relatively low proportion of water.
15 In some cases, it is also desirable to restrict the production of hydrocarbon gas from a
well.
In addition, where fluid is produced from a long interval of a formation
penetrated by a wellbore, it is known that balancing the production of fluid along the
interval can lead to reduced water and gas "coning," and more controlled
20 conformance, thereby increasing the proportion and overall quantity of oil produced
from the interval. Inflow control devices (ICDs) have been used in the past to restrict
flow of produced fluid through the ICDs for the purpose of balancing production
along an interval. For example, in a long horizontal wellbore, fluid flow near the
"heel" of the wellbore may be more restricted as compared to fluid flow near a "toe"
of the wellbore, to counteract a horizontal well's tendency to produce at a higher flow
rate at the "heel" of the well as compared to the "toe."
However, after the onset of water or gas production in the well due to coning.
it is sometimes desirable to reduce any flow restrictions created by the ICDs in order
5 to maximize production. Thus, while ICDs are desirable for delaying the point when
water or gas production begins, higher flow rates into the well may be needed after
this point in time in order to extract any remaining hydrocarbons from the surrounding
formation. Further, it may also be desirable to isolate the well from the surrounding
formation without the need for physical intervention into the well, such as for setting
10 particular tools in the well or for abandoning the well.
SUMMARY OF THE INVENTION
In an embodiment, a flow control device comprises a tubular member having
an interior passageway for conveying fluids, a housing disposed about the tubular
member and forming a chamber between the housing and the tubular member, where
15 the housing is divided into a control chamber and a valve chamber, a piston disposed
within the control chamber and moveable between a first piston position and a second
piston position that is displaced from the first piston position, where the piston divides
the control chamber into first and second portions, and a valve disposed within the
valve chamber and moveable between a first valve position and a second valve
20 position that is displaced from the first valve position, where the valve provides for
selective fluid communication between a first portion of the valve chamber and a
second portion of the valve chamber. The piston provides a first flow path between
the control chamber and interior passageway of the tubular member in the first piston
posifion, and the valve provides a second flow path between the valve chamber and
25 interior passageway of the tubular member in the second valve position.
In an embodiment, a flow control device for control of fluid flow through a
- 3 -
tubular member comprises a control chamber having a piston disposed therein, where
the piston is moveable from an open piston position to a closed piston position by the
application of a first fluid pressure, and a valve chamber having a valve therein, where
the valve is moveable from a closed valve position to an open valve position by the
5 application of a second fluid pressure. A seal preventing fluid flow through the
control chamber into the tubular member is formed in the closed piston position, and a
flow path through the valve chamber and into the tubular member is formed in the
open valve position.
In an embodiment, a method for controlling flow into a tubular member
10 comprises providing fluid communication between an interior of the tubular member
and a subterranean formation along a first flow path, substantially sealing the first
flow path in response to a first pressure, establishing a second flow path between the
interior of the tubular member and the subterranean formation in response to a second
pressure, and providing fluid communication between the interior of the tubular
15 member and the subterranean formation along the second flow path.
These and other features and characteristics will be more clearly understood
from the following detailed description taken in conjunction with the accompanying
drawings and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
20 For a detailed description of the disclosed embodiments, reference will now be
made to the accompanying drawings in which:
Figure 1 is a schematic illustration of a well system including a plurality of
flow control devices according to an embodiment.
Figure 2 is a cross-sectional view of an embodiment of a flow control device.
Figure 3A is a cross-sectional view of an embodiment of the fiow control
device shown in a first configuration.
Figure 3B is a cross-sectional view of an embodiment of the fiow control
device of Figure 3 A shown in a second configuration.
5 Figure 3C is a cross-sectional view of an embodiment of the flow control
device shown in a third configuration.
Figure 3D is a cross-sectional view of an embodiment of the flow control
device shown in a fourth configuration.
Figure 4 is an isometric view of an embodiment of a valve body and collet
10 assembly.
Figure 5A is a cross-sectional view of an embodiment of a flow control device
including a restraining member in the form of a J-Slot mechanism shown in a first
configuration.
Figure 5B is a cross-sectional view of an embodiment of the flow control
15 device of Figure 5 A with the J-Slot mechanism shown in a second configuration.
Figure 5C is a cross-sectional view of an embodiment of the flow control
device of Figure 5 A with the J-Slot mechanism shown in the third configuration.
Figure 5D is a cross-sectional view of an embodiment of the flow control
device of Figure 5 A with the J-Slot mechanism shown in the fourth configuration.
20 Figure 6 is a top view of an embodiment of the J-Slot shown in Figures 5A-5D.
Figure 7 is an isometric view of an embodiment of a lug ring for the J-Slot
mechanism of Figures 5A-5D.
DESCRIPTION OF INVENTION w.r.t. DRAWINGS
It should be understood at the outset that although illustrative implementations
- 5 -
of one or more embodiments are disclosed herein, the disclosed apparatus, systems
and methods may be implemented using any number of techniques, whether currently
known or in existence. The disclosure should in no way be limited to the illustrative
implementations, drawings, and techniques illustrated below, but may be modified
5 within the scope of the appended claims along with their full scope of equivalents.
Certain terms are used throughout the following description and claims to refer
to particular features or components. The drawings are not necessarily to scale.
Certain features and components herein may be shown exaggerated in scale or in
somewhat schematic form and some details of conventional elements may not be
10 shown in interest of clarity and conciseness.
Unless otherwise specified, any use of any form of the terms "'connect."
"engage," "couple," "attach," or any other term describing an interaction between
elements is not meant to limit the interaction to direct interaction between the
elements and may also include indirect interaction between the elements described. In
15 the following discussion and in the claims, the terms "including" and "comprising"
are used in an open-ended fashion, and thus should be interpreted to mean "including.
but not limited to ...". Reference to up or down will be made for purposes of
description with "up," "upper," "upward," or "uphole" meaning toward the surface of
the wellbore and with "down," "lower," "downward," or "downhole" meaning toward
20 the terminal end of the well, regardless of the wellbore orientation. The term "zone"
or "pay zone" as used herein refers to separate parts of the wellbore designated for
treatment or production and may refer to an entire hydrocarbon formation or separate
portions of a single formation, such as horizontally and/or vertically spaced portions
of the same formation. The various characteristics mentioned above, as well as other
25 features and characteristics described in more detail below, will be readily apparent to
those skilled in the art with the aid of this disclosure upon reading the following
detailed description of the embodiments, and by referring to the accompanying
drawings.
The present disclosure describes an apparatus and method for quickly and
30 efficiently bypassing a flow restriction (e.g., an ICD) after it has been installed
downhole in a well and sealing off the well from the surrounding formation without
the need for physically intervening into the well. While a number of bypass
mechanisms may be used with the apparatus and method described herein, it will be
appreciated that the flow control device may be used to close off a first flow path
through the flow restriction in response to a first pressure, and at the same time or
5 thereafter open a second flow path in response to a second pressure. While the first
pressure can be greater than, less than, or equal to the second pressure, having the first
pressure be less than the second pressure may allow for the first flow path to be closed
off and then the second flow path to be opened at a later time. A plurality of fiow
control devices may be used in a production string to close off a plurality of flow
10 restrictions in response to the first pressure, and then open a plurality of bypass flow
paths in response to the second pressure. Thus, multiple flow paths may be changed
in response to one or more pressures, which may represent an advantage over the use
of flow restrictions alone. Further, multiple flow paths may be changed using
pressure alone without physically intervening in the well, which may represent an
15 advantage over previous systems requiring the use of setting tools conveyed within the
wellbore.
Referring initially to FIG. 1, therein is depicted an exemplary well system 10
comprising a wellbore 12 with both a substantially vertical section 14 and a
substantially horizontal section 16, casing 18, tubular string 20, a plurality of spaced
20 apart packers 22 and flow control devices 24, and a formation 26.
Production of hydrocarbons may be accomplished by flowing fluid containing
hydrocarbons from the formation 26, through the uncased and open horizontal
wellbore 16 and into the tubular string 20 through the plurality of flow control devices
24. In this example, the flow control devices 24 provide for the filtering of unwanted
25 material from the formation 26 and for the metering of fluid input from the formation
into the tubular string 20. Packers 22 isolate each individual flow control device 24
into different zones or intervals along the wellbore 12 by providing a seal between the
outer wall of the wellbore 12 and tubular string 20.
Frictional effects of the fluid flow through the tubular string 20 may result in
30 increased fluid pressure loss in the uphole section of the tubular string 20 relative to
the downhole section of the tubular string 20 disposed in the horizontal wellbore 16.
This pressure loss results in an increased pressure differential between the uphole
sections of the tubular string 20 disposed in the horizontal section 16 and the
formation 26, which in turn results in a higher flow rate into the uphole section of the
tubular string 20. Thus, isolating each fluid control device 24 allows for the tailoring
5 of the metering capability of each fluid control device 24 to result in a more even flow
rate into each section of the tubular string 20. For instance, the uphole flow control
devices 24 could include larger flow restrictions to act against the larger differential
pressure forcing fluid into the flow control devices.
Although FIG. 1 depicts the flow control devices 24 in an open and uncased
10 horizontal wellbore 16, it is to be understood that the flow control devices are equally
suited for use in cased wellbores. For instance, the flow control devices 24 and
packers 22 may be used for flow control purposes when injecting chemicals, such as
acids, and/or perforating the casing for the later production of hydrocarbons. Further,
although FIG. 1 depicts single flow control devices 24 as being isolated by the packers
15 22, it is to be understood that any number of flow control devices 24 may be grouped
together and isolated by the packers 22, without departing from the principles of the
present disclosure. In addition, even though FIG. 1 depicts the flow control devices
24 in a horizontal wellbore 16, it is also to be understood that the flow control devices
are equally suited for use in wellbores having other directional configurations
20 including vertical wellbores, deviated wellbores, slanted wellbores. multilateral
wellbores and the like.
An embodiment of a flow control device may comprise a control chamber
having a piston therein that is moveable from an open piston position to a closed
position by the application of a first fluid pressure and a valve chamber having a valve
25 therein that is moveable from a closed valve position to an open valve position by the
application of a second fluid pressure. Also, a seal preventing fluid flow through the
control chamber into the tubular member is formed in the closed piston position and a
flow path through the valve chamber and into the tubular member may be formed in
the open valve position. The flow control device may further comprise a restraining
30 member disposed adjacent to the piston, wherein the restraining member is actuated
by movement of the piston in response to the first fluid pressure. The flow control
8-
device may also comprise a restraining member disposed adjacent to the valve.
wherein the restraining member is actuated by movement of the valve in response to
the second fluid pressure. The fluid flow through the control chamber into the tubular
member may create a first pressure drop while the fluid flow through the valve
5 chamber into the tubular member may create a second pressure drop, which may be a
pressure drop that is greater than, less than, or equal to the first pressure drop. Also,
the first fluid pressure may be greater, smaller, or substantially equal to the second
fluid pressure.
Referring now to FIG. 2, therein is depicted a cross-sectional view of an
10 embodiment of a flow control device 100 suitable for use as flow control device 24
previously described with reference to FIG. 1. Flow control device 100 generally
includes a flow restrictor portion 100a and a bypass valve portion 100b. Flow
restrictor portion 100a generally includes a pipe or tubular member 102, a filter 142, a
first port 114, a housing 104, a flow restrictor member 164, a piston 106, a flange 110,
15 a second port 120, a shear member 116, and a third port 118.
Pipe 102 is any tubular member capable of being used downhole and
communicating fluid at high pressures. Pipe 102 includes an internal fluid
passageway 102a, through which fluids may be conveyed in both uphole and
downhole directions, and radially directed first port 114 and third port 118 that extend
20 through the wall of the tubular pipe 102.
Housing 104 is an annular member disposed about the pipe 102 and includes a
cylindrical outer wall 104a, a retaining flanged portion 104c extending radially
therefrom, and a fixed flanged portion 104b extending radially from the cylindrical
outer wall 104a and fixed to the outer surface of the pipe 102. Together, the outer
25 wall 104a and the flange 104b define a first chamber 144 between the housing 104
and the pipe 102. Third port 118 provides for fluid communication between the
internal fluid passageway 102a and the portion of the first chamber 144 defined by a
second side 106f of piston 106, cylindrical outer wall 104a, and the fixed flanged
portion 104b of the housing 104. Opposite fixed flanged portion 104b and adjacent to
30 filter 142 is internal flange 104d that extends radially into the first chamber 144 from
outer wall 104a and, as described in more detail below, defines a portion of the second
-9
port 120.
In the embodiment shown in FIG. 2, flow restrictor 164 is an annular member
that is disposed about the pipe 102. In this embodiment, restrictor 164 has an elongate
cylindrical portion 164a fixed to the pipe 102. Flow restrictor 164 also includes at
5 least one through passage 164b extending in an axial direction through tubular portion
164a.
Flange 110 is an elongated member extending radially outward from the pipe
102. Flange 110 is fixed to the pipe 102 and includes an outwardly facing seal 112.
Piston 106 is an annular member disposed about the pipe 102 and adapted for
10 sliding engagement relative to the housing 104 and the pipe 102. Piston 106 is
configured similarly to the housing 104, and includes an elongated outer wall 106a. a
lower flanged portion 106b, a sealing flanged portion 106d and an upper flanged
portion 106c opposite the lower flanged portion. The lower flanged portion 106b
extends inwardly from the outer wall 106a and retains the annular seals 108a and
15 108b, which sealingly engage the inner surface of the housing 104 and the outer
surface of the pipe 102, respectively. The lower flanged portion 106b also includes a
first side 106e disposed adjacent to the shear member 116 and a second side I06f
disposed adjacent to the third port 118. The sealing flanged portion 106d includes a
seal 108c for a sealing engagement with the outer surface of the cylindrical portion
20 164a of the flow restrictor 164. The upper flanged portion 114c includes an inwardly
facing sealing surface for sealingly engagement with the seal 112 retained in the
flange 110. The piston seals 108a and 108c divide the first chamber 144 into two
portions, with one portion containing the first port 114, flange 110, flow restrictor 164,
second port 120, sealing flange 106d, shear member 116, and the other portion
25 containing the third port 118.
The shear member 116 is a frangible pin disposed in a slot 166 or other such
recess in the wall of pipe 102 in first chamber 144. Also, the shear member 116 is
disposed so as to engage the first side 106e of the piston 106. The longitudinal axis of
the shear member 116 is perpendicular to the longitudinal axis of the pipe 102. In an
30 embodiment, a plurality of shear members may be used about pipe 102 to produce a
desired retaining force.
Referring still to FIG 2, bypass valve portion 100b generally includes the pipe
or tubular member 102, a filter 148, a housing 122, a magnet 146, a valve 150, a shear
flange 132, a fourth port 140 and a fifth port 138. Bypass valve portion 100b and pipe
102 include a radially directed fifth port 138 that extends through the tubular wall of
5 the pipe 102.
Housing 122 is an annular member disposed about the pipe 102 and includes a
cylindrical outer wall 122a, a cylindrical inner wall 122d, an interior flanged portion
122b extending radially from the cylindrical outer wall 122a to the cylindrical inner
wall 122d, with the cylindrical inner wall 122d fixed to the outer surface of the pipe
10 102. Together, the outer wall 122a, the interior flanged portion 122b and the inner
wall 122d define a second chamber 154. The cylindrical outer wall 122a includes a
slot 122g for the insertion of the shear flange 132. A bore 122f extends radially
through the inner wall 122d to provide for a passage to the fifth port 138. which
provides for fluid communication between the internal fluid passageway 102a and the
15 second chamber 154. Opposite the interior flanged portion 122b are outer flanged
portion 122c and inner flanged portion 122e, both extending radially into the second
chamber 154 and, as described in more detail below, define a portion of the fourth
port 140.
In an embodiment, the valve portion may comprise a magnet 146. Magnet
20 146 may be cylindrical in shape in the embodiment shown and capable of producing a
magnefic field that produces a force on ferromagnetic materials. Magnet 146 is fixed
to the interior flanged portion 122b and extends substantially from the inner surface of
the cylindrical outer wall 122a to the outer surface of the cylindrical inner wall 122d.
Also, magnet 146 has a longitudinal axis that is parallel to the longitudinal axis of the
25 pipe 102.
Valve 150 generally includes a valve body 134, an internal throughbore 152,
0-ring seal 130, annular slot 156, valve plug 128, collet fingers 126, and retaining ring
124. The valve body 134 is a generally cylindrical member and is slidingly
engageable with the cylindrical outer wall 122a and cylindrical inner wall 122d of the
30 housing 122. The valve body 134 includes a central throughbore 152 that extends
along the longitudinal axis of the valve body. The valve body 134 also includes an
annular slot 156 that extends circumferentially about the outer surface of the valve
body 134. An annular groove 158 is also disposed circumferentially about the outer
surface of the valve body 134, where it houses the 0-ring seal 130. 0-ring seal 130
seals between the cylindrical outer 122a and inner 122d surfaces of the housing 122
5 with the outer surface of the valve body 134.
Now referring to FIGS. 2 and 4, fixed to the valve body 134 are a plurality of
collet fingers 126, which extend axially towards the interior flanged portion 122b of
the housing 122, and terminate at inwardly facing lip 162. Lip 162 of the collet
fingers 126 is compressed radially inwardly by the retaining ring 124. The fingers
10 126 are manufactured to be biased to bend outwardly but are restrained by the
retaining ring 124 to maintain a uniform internal diameter along their length up until
lip 162. The cylindrical retaining ring 124 is fixed to the cylindrical outer 122a and
inner 122d portions of the housing 122 and thus may not move along the longitudinal
axis of the housing 122. However, the collet fingers 126 slidingly engage the inner
15 cylindrical surface of the retaining ring 124.
Disposed within the central throughbore 152 is the valve plug 128. Fwen
though the plug 128 is depicted as spherical in shape, valve plugs 128 could have
alternate shapes including cylindrical configurations, substantially cylindrical
configurations or other configurations so long as the plug 128 is capable of creating a
20 seal within the valve body 134 and of being ejected from the valve body 134. as is
described below. Additional details concerning these additional valve plug designs are
disclosed in U.S. Patent Publication No. 2011/0253391, the entire disclosure of which
is incorporated herein by this reference. Plug 128 is permitted to move axially
through a portion of the central throughbore 152 but is restrained from complete axial
25 freedom by a shoulder 160 and the lip 162 of the collet fingers 126. Shoulder 160 and
lip 162 reduce the diameter of the internal throughbore 152 to a smaller diameter than
that of the valve plug 128. The plug 128, having a larger diameter than the shoulder
160, may seal against the shoulder 160 to prevent a fluid flow from the fifth port 138
to the fourth port 140. Moreover, because the diameter of the plurality of collet
30 fingers 126 at lip 162 is smaller than the diameter of the plug 128. contact between the
plug 128 and the lip 162 forms a seal preventing or substantially restricting a fluid
12
flow from the fourth port 140 to the fifth port 138.
Shear flange 132 is disposed in the slot 122g of the cylindrical outer wall 122a
of the housing 122. Shear flange 132 is an elongate member with a longitudinal axis
perpendicular to the longitudinal axis of the pipe 102 and extends from the slot 122g
5 to the annular slot 156 of the valve body 134.
An exemplary operation of the flow control device 100 of FIG. 2 is best
understood with reference to FIGs 3A-3D. Referring first to FIG. 3A, during normal
operation when producing hydrocarbons via a well system, the pressure within pipe
102 will be lower than the pressure of fluid within a surrounding formation. At this
10 time, the piston 106 is disposed in a first position where the first side 106c acts on the
shear member 116 and the seal 108c of the sealing flange 106d is sealingly engaged
with the outer surface of the flow restrictor 164. In this first configuration of the flow
control device 100, due to the external differential pressure, a flow path 302 is
established where fluid within the wellbore 12 enters the filter 142 of the flow
15 restrictor portion 100a of the flow control device 100 in order to remove any entrained
sand or other debris and particulates. The filter 142 illustrated in FIG. 3A is a type
known as "wire-wrapped," where wire is closely wrapped helically about pipe 102,
with the spacing between each windings of wire designed to allow the passing of fluid
but not of sand or other debris above a certain size. Other types of filters may also be
20 used, such as sintered, mesh, pre-packed, expandable, slotted, perforated and the like.
Following filtration, fluid enters the flow control device 100 through the first
port 120 and then through an existing gap between the flange 110 and the flanged
portion 106c of the piston 106. Next, the flow path 302 is directed through the
internal flow passage 164b of the flow restrictor 164. The flow path 302 cannot
25 circulate around the flow restrictor 164 due to the sealing engagement between the
seal 108c of the sealing flanged portion 106d and the outer surface of the cylindrical
portion 164a of the flow restrictor 164. Upon exiting the flow restrictor 164. the flow
path 302 enters the first port 114 and then into the internal fluid passageway 102a.
While the external differential pressure between the fluid within the wellbore
30 12 and the fluid within the internal passageway 102a also acts on the bypass valve
portion 100b of the flow control device 100, the flow path between the fourth port 140
13
and the fifth port 138 may be substantially blocked due to the configuration of the
valve 150. Fluid from the wellbore 12 is conveyed through the filter 148, into the
second chamber 154, and enters the internal throughbore 152. Fluid from the
wellbore 12 may not bypass the valve body 134 due to the sealing engagement
5 between the seal 130 in the annular groove 158 and the housing 122 and the external
surface of the pipe 102. Further, fluid entering the internal throughbore 152 may not
flow through the fifth port 138 due to the sealing engagement between the valve plug
128 and the lip 162 of the collet fingers 126. Thus, the only flow path established in
this first configuration of the flow control device 100 is the flow path 302, in which
10 fluid enters the flow restrictor portion 100a from the second port 120, flows through
the flow restrictor 164, and enters the internal passageway 102a of the pipe 102
through the first port 114.
Referring again to FIG. 1, while producing from the well, it may become
advantageous to stop production and shut in the well system 10 by sealing the tubular
15 string 20 off from the fluid within the formation 26 in order, for example, to service or
perform maintenance on the well system 10. Further, it also may be advantageous at a
certain point in the production process to seal off particular intervals in the production
string 20 by individually sealing particular specific flow control devices 24. For
instance, certain portions of the horizontal section 16 of the wellbore 12 may contain
20 high, permeability zones, resulting in faster and more severe water coning in these
zones compared to lower permeability zones. Thus, it is sometimes advantageous to
only seal off the flow control devices 24 in high permeability zones, in order to delay
the event of water production from the formation 26 to the tubular string 20.
Referring now to FIG. 3B, in order to seal the internal passageway 102a of the
25 pipe 102 from the surrounding wellbore 12, the flow control device 100 is
reconflgured by creating an internal pressure diflFerential, wherein the pressure within
the internal passageway 102a is higher than the fluid pressure within the wellbore 12.
This internal pressure differential may be created by a first pressure signal that
pressurizes the internal passageway 102a through the pumping of fiuid from the
30 surface of the well system 10, as illustrated in FIG.l, downhole into the tubular string
20.
14
Once the internal pressure differential is created by pressurizing of the internal
passageway 102a, a flow path 304 is established. Flow path 304 allows fluid to flow
from the pressurized internal passageway 102a into the radially disposed first port 114
and third port 118 of the flow restrictor portion 100a and the fifth port 138 of the
5 bypass valve portion 100b. As the flow path 304 enters the third port 118 and the first
port 114 of the flow restrictor portion 100a, the high pressure of the fluid within the
flow path 304 produces a pressure force on the piston 106. The high pressure of the
fluid in flow path 304 acts on the first side 106e, second side 106f, and third side 106g
of the piston 106. The second side 106f and third side 106g both face in the direction
10 away from the second port 120 and thus pressure acting on these two faces produces a
pressure force on the piston 106 in the direction of the second port 120. The total
force on the piston 106 produced by the pressure acting on the second side 106f and
the third side 106g is proportionate to the surface areas of the second side 106f and
third side 106g. The high pressure produced by the fluid in the flow path 304 also acts
15 on the first side 106e of the piston 106, and since the first side faces towards the
second port 120, pressure acting on the first side 106e produces a pressure force on the
piston 106 in the direction away from the second port 120.
A net force on the piston 106 is produced by the summation of the pressure
forces acting on the first side 106e, second side 106f, and third side 106g. Thus, given
20 that the net force on the piston 106 produced by the pressure of the fluid within the
flow path 304 acts in the direction of the second port 120, the piston 106 is forcibly
compelled in the direction of the second port 120, and thus acts on and transfers a
force to the shear member 116.
The shear member 116 is frangibly fixed to the radial slot 166 of the pipe 102
25 and is designed to shear upon the application of a predetermined force by the piston
106 acting on the shear member 116. The force application necessary to shear the
member 116 is predetermined and thus, given the known relationship between the net
force acting on the piston 106 and the pressure delivered by the fluid within the flow
path 304, an operator of a well system may apply a predetermined first pressure to the
30 internal passageway 102a of the pipe 102 to create a predetermined internal
differential pressure, such that the net force acting on the piston 106 will in tum
- 15
produce a force on the shear member 116 large enough to shear the member 116,
allowing the piston to move axially towards the second port 120, compelled by the
pressure force from the flow path 304.
Upon axial movement of the piston 106 in the direction of the second port 120,
5 the upper flanged portion 106c of the piston 106 eventually impacts the retaining
flanged portion 104c of the housing 104, preventing the piston from any flirther axial
movement in the direction of the second port 120. As the upper flanged portion 106c
makes contact with the retaining flanged portion 104c, a seal is formed between the
upper flanged portion 106c of the piston 106 and the seal 112 of the flange 110 fixed
10 to the pipe 102. This sealing engagement prevents any fluid within the flow path 304
from further escaping from the flow control device 100 into the wellbore 12 through
the second port 120, thus sealing the flow restrictor portion 100a of the flow control
device 100.
Regarding the bypass valve portion 100b of the flow control device 100, high
15 pressure fluid from the internal passageway 102a flows into the fifth port 138 and into
the second chamber 154. Further, the fluid within the flow path 304 enters the internal
throughbore 152 of the valve 150. High pressure from fluid within the flow path 304
then acts against the valve plug 128, compelling the plug 128 to move axially in the
direction of the fourth port 140. As the plug 128 moves axially within the internal
20 throughbore 152, it contacts shoulder 160 of the valve body 134. This contact forms a
seal, preventing fluid in the flow path 304 from continuing through the throughbore
152 and out of the fourth port 140. Further, fluid within the flow path 304 may not
divert around the valve body 134 due to the sealing engagement of the seal 130 with
the housing 122. Thus, in this second configuration, the bypass valve portion 100b of
25 the flow control device 100 seals the fluid within the internal passageway 102a from
the external wellbore 12.
Once the second configuration of the flow control device 100 has been
established, wherein the flow restrictor portion 100a and the bypass valve portion
100b have both sealed the internal passageway 102a from the external wellbore 12.
30 pressure within the internal passageway 102a may be reduced in order to perform
work within the well, abandon the well, or for other purposes, and the passageway
-16
102a will remain sealed.
Referring again to FIG. 1, now that at least some intervals in the well system
10 have been shut in by sealing at least some intervals in the tubular string 20 from the
formation 26, it may be advantageous to reopen the sealed flow control devices 24 for
5 further production into the tubular string 20. Further, it may be advantageous to
reduce the flow restriction through the flow control devices 24 in order to increase the
flow rate entering the tubular string 20 from the formation 26.
For instance, a uniform flow rate for each individual flow control device 24 is
often initially desired in order to delay water or gas production into the tubular string
10 20 from the formation 26. Once a well system 10 has begun producing water or gas
from the formation 26, the advantage of a uniform metered flow from flow control
devices 24 is diminished, and instead, increased flow rates are desired in order to
capture any remaining hydrocarbons left in the formation 26. Thus, a means for
reducing flow restrictions within the flow control devices 24 then becomes desirable
15 in order to increase the flow rate entering the tubular string 20 from the formation 26.
In order to open the flow control devices 24, devices 24 may be actuated into a
third configuration, as illustrated by FIG. 3C. To position the flow control device 100
into a third configuration, a second internal pressure differential is created through the
application of a second pressure signal to the internal passageway 102a. This second
20 internal differential pressure, wherein the pressure within the passageway 102a is
higher than the pressure of the fluid within the annular region between the housing
104 and the wellbore 12, may be established in a similar manner as the creation of the
first internal pressure differential, for example, by flowing pressurized fluid from the
surface of the well system of FIG. 1 downhole into the tubular string 20.
25 Referring again to FIG. 3C, the second internal pressure differential creates the
fluid flow path 306, in which fluid enters the first port 114 and third port 118.
Regarding the flow restrictor portion 100a, the fluid in flow path 306 is not allowed to
exit the second port 120 due to the sealing engagement between the upper flanged
portion I06c of the piston 106 and the seal 112 of the flange 110. While the pressure
30 of the fluid within the flow path 306 may act on the piston 106, because the pressure
force acting on the second side 106f and third side 106g is larger than the pressure
17-
force acting on the first side 106e, due to the larger combined surface area of the
second side 106f and the third side 106g, the net force exerted on the piston 106
compels the piston 106 in the direction of the second port 120, and thus the piston
upper flange 106c remains in a sealing engagement with the seal 112.
5 Regarding the bypass valve portion 100b, fluid flow in flow path 306 created
by the second differential pressure enters the fifth port 138 and produces a pressure
force on the portion of the surface of the valve plug 128 facing the interior flanged
portion 122b of the housing 122. The pressure force applied to the valve plug 128 is
transferred to the valve body 134 due to the sealing engagement between the plug 128
10 and the shoulder 160 of the valve body 134. Further, the fluid in flow path 306 may
not be directed around the valve body 134 due to the sealing engagement of the seal
130 and the housing 122.
The pressure force exerted on the surface of the plug 128 that is transferred to
the valve body 134 is further conveyed from the valve body 134 to the shear flange
15 132 disposed partially in the slot 122g of the housing 122 and the annular slot 156.
The shear flange 132 is designed to shear when a predetermined force is applied to its
external surface. Given that the amount of force applied to the shear flange 132 is a
function, at least in part, of the pressure applied within the internal passageway 102a
and the diameter of the valve plug 128, an operator of a well system, such as the well
20 system 10 illustrated in FIG. 1, can apply a predetermined pressure to the internal
passageway 10 to shear the shear flange 132 in order to allow for axial movement by
the valve body 134 of the valve 150.
Further, the shear flange 132 may be designed to withstand a higher pressure
within internal passageway 102a without shearing than the shear member 116 of the
25 flow restrictor portion 100a. Thus, the application of the first internal pressure signal
creates a large enough shearing force to shear the shear member 116 but not the shear
flange 132, allowing for the first actuation of the piston 106 and then a second
actuation of the valve body 134 of the valve 150.
The pressure force generated by the fluid within the flow path 306. having
30 sheared the shear flange 132, continues to act against the outer surface of the valve
plug 128, forcibly moving the valve body 134 axially towards the fourth port 140 into
a second position. During the axial movement of the valve body 134, an outer face
168 of the valve body 134 impacts the outer flanged portion 122c of the housing 122,
restraining the valve body 134 from further axial movement in the direction of the
fourth port 140. Translating valve body 134 to the second position in which outer face
5 168 abuts outer flanged portion 122c, allowing the collet fingers 126 to axially slide
free from the retaining ring 124. Now free from the retaining ring 124, the collet
fingers 126 radially expand outward slightly, increasing the diameter of the internal
throughbore 152 for the portion of the valve body 134 where the lips 162 are disposed.
The increased diameter is now larger than the diameter of valve plug 128, allowing for
10 the plug 128 to slidingly pass unobstructed through the opening defined by inwardly
extending lips 162.
Although plug 128 may now slide axially through lip 162 due to the increased
diameter of the opening defined by annular lip 162, the pressure force created by flow
path 306 forcibly compels plug 128 against shoulder 160. Thus, in order to ftilly open
15 valve 150, an external differential pressure is created to compel plug 128 in the
direction of collet fingers 126, a process illustrated by FIG. 3D. Referring to FIG. 3D,
flow path 308 is established by reducing the pressure within internal passageway
102a, such as by pumping out of tubular string 20 of FIG. 1 at the surface of welt
system 10. Having created a state where pressure of the fluid within wellbore 12 is
20 higher than the pressure of fluid within internal passageway 102a, fluid along flow
path 308 enters into the flow control device 100.
Regarding flow restrictor portion 100a of flow control device 100, fluid from
wellbore 12 may enter through second port 120 but cannot pass the sealing
engagement between upper flanged portion 106c of piston 106 and seal 112 of flange
25 110. Specifically, while fluid entering second port 120 will be of higher pressure than
fluid within internal passageway 102a, fluid within passageway 102a may enter
through first port 114 and third port 118, creating a pressure force acting on piston 106
in the axial direction of second port 120. This pressure force is larger than the
pressure force acting on upper flanged portion 106c in the opposite direction because
30 the pressure force has a larger surface area of the piston 106 to act upon, resulting in a
larger force on the piston 106 in the direction of second port 120. Thus, a flow path
19
cannot be established between second port 120 and first port 114.
Regarding bypass valve portion 100b of flow control device 100, the external
pressure differential results in fluid flow along flow path 308 entering fourth port 140.
Once passing through filter 148, fluid conveyed in flow path 308 enters internal
5 throughbore 152 of valve 150. Pressure from fluid in flow path 308 acts on the
surface of valve plug 128 facing fourth port 140, forcibly compelling plug 128 axially
in the direction of magnet 146. Plug 128 slides axially past radially expanded lip 162
and retaining ring 124, coming to rest along the surface of magnet 146. which
provides a magnetic force upon plug 128, locking it into a secured, resting position
10 where it may not obstruct the flow along flow path 308. In an embodiment, the
diameter of bore 122f and fifth port 138 may be of a size larger than valve plug 128,
allowing the valve plug to pass through bore 122f and fifth port 138 and be ejected
into the internal passageway 102a of pipe 102.
While FIG. 3D illustrates the use of magnet 146 as a mechanism for
15 restraining the valve plug 128, another embodiment is to provide a bypass valve
portion 100b such that bore 122f and fifth port 138 are larger in diameter than plug
128, allowing plug 128 to slide through bore 122f and port 138 so it can be expelled
into internal passageway 102a and out of chamber 154.
In both arrangements, now unobstructed by valve plug 128, fluid along flow
20 path 308 flows through retaining ring 124 and through fifth port 138 into the internal
passageway 102a of pipe 102. Because bypass valve portion 100b, as illustrated in
FIG. 3D, does not include a flow restrictor, a higher flow rate through bypass valve
portion 100b may be established versus flow restrictor portion 100a when flow
restrictor portion 100a is in its open state, as illustrated in FIG. 3A. However, a flow
25 restrictor may be installed within chamber 154 of bypass valve portion 100b, allowing
for the restriction of flow along flow path 308, similar to the restriction offered by
flow restrictor member 164. This design may be beneficial where a well system
operator wishes to have similar flow rates through flow restrictor portion 100a and
bypass valve portion 100b, when they are each in their open configurations.
30 For instance, a well system operator may wish to use filter 148 as a redundant
filter and to only flow through bypass valve portion 100b after filter 142 has clogged
20-
from extensive use. Thus, the operator may wish to maintain the same flow rate from
the fluid within wellbore 12 into the internal passageway 102a of pipe 102, and will
only switch from flow restrictor portion 100a to bypass valve portion 100b to take
advantage of the redundant filtering capability offered by filter 148.
5 Furthermore, an alternative embodiment may comprise a flow control device
where shear member 116 of flow restrictor portion 100a and shear flange 132 of
bypass valve portion 100b are configured to both shear at the same pressure
differential between internal passageway 102a and wellbore 12. Thus, in this
embodiment the flow restrictor portion 100a and bypass valve portion 100b would
10 actuate at the same time, allowing the flow control device 100 to move from a first
flow path 302 (FIG. 3A), to flow path 304 (FIG. 3B) and then immediately to flow
path 308 (FIG. 3D), skipping the shut in configuration, as illustrated in FIG. 3C. Also,
in another embodiment, shear flange 132 may be configured to shear at a lower
differential pressure between internal passageway 102a of pipe 102 and the wellbore
15 12 than shear member 116, resulting in the bypass valve portion 100b actuating first,
at a lower differential pressure, and flow restrictor portion 100a actuating second at a
higher differential pressure.
With reference to FIGS. 2-4, a shear flange 132 was described as a restraining
mechanism or releasable latch that prevents axial movement of valve 150 towards the
20 fourth port 140 until a pressurization of predetermined magnitude caused valve 150 to
shear the shear flange 132, thereby freeing the valve to move axially by means of a
pressure force acting on valve plug 128. Other releasable latches or restraining
mechanisms can likewise be employed, including those that do not require the
shearing of frangible members. For example, and referring now to FIG. 5A. another
25 type of restraining mechanism is disclosed as employed in flow control device 500.
More specifically, the restraining mechanism employed in flow control device 500 is a
partial J-slot mechanism. In this embodiment, an annular housing 508 is disposed
about pipe 102 and includes an inwardly extending flanged portion 508b extending
radially from a cylindrical portion 508a and fixed to the pipe 102. Housing 508 also
30 features an integral outer flanged portion 508c extending radially from cylindrical
portion 508a. Inner flanged portion 508b and cylindrical portion 508a partially define
21 -
chamber 542.
Disposed within chamber 542 is piston 510 featuring cylindrical portion 510a,
inner flanged portion 510b and outer flanged portion 510c. A biasing member 520 is
also disposed within chamber 542 and is biased to forcibly act against inner flanged
5 portion 508b and a first face 538 of piston 510. A flange 514 with an accompanying
seal 516 is fixed against the outer surface of pipe 102, with seal 516 provides for
sealing engagement with the outer flanged portion 510c of piston 510. An annular
groove is also disposed in the cylindrical portion 510a, where it houses one or more
0-ring seals 512a, 512b. O-ring seals 512a, 512b seal between the piston 510 and
10 inner surfaces of the housing 508 with the outer surface of the wellbore tubular 102.
An irregularly shaped J-Slot 522 is disposed within a top surface 536 of piston
510. A ring 524 is disposed within a slot in the cylindrical portion 508a of housing
508. Ring 524 is fixed axially by housing 508 but is free to rotate within housing 508
and about pipe 102. Fixed to ring 524 is a radially-extending lug 526, disposed within
15 a portion of slot 522. Lug 526 restricts the degree of rotation afforded ring 524 due to
contact between lug 526 and the outer wall of slot 522.
FIG. 6 illustrates the top surface 536 of piston 510. Disposed within top
surface 536 is the irregularly shaped J-Slot 522, and within slot 522 is disposed lug
526. Lug 526, depending on the position of piston 510, may occupy four diflFerent
20 positions in slot 522: first position 534a, second position 534b, third position 534c,
fourth position 534d and fifth position 534e. FIG. 6 is shown oriented such that the
top of FIG. 6 is axially proximal to the biasing member 520 (FIG. 5 A) and the bottom
of FIG. 6 is proximal to the outer flanged portion 510c (FIG. 5A). FIG. 7 illustrates
the shape of ring 524 and lug 526, as they are configured in flow control device 500 of
25 FIG. 5A.
Referring to FIG. 5A, flow control device 500 is shown in a production state
where an external pressure differential results in flow path 528, wherein fluid from
wellbore 12 enters flow control device 500 through second port 120, flows through
flow restrictor 164, and into internal passageway 102a of pipe 102 through first port
30 114. Piston 510 occupies a first position where first face 538 of piston 510 is acted
upon by biasing member 520. Biasing member 520 produces a force on piston 106 in
22
the direction of fifth port 504. However, piston 510 is axially restrained from
movement in the direction of fifth port 504 due to contact between lug 526 and slot
522. Referring to FIGS. 5A and 6, while piston 510 occupies this first position, lug
526 occupies first posifion 534a (FIG. 6), and is in contact with the outer wall of slot
5 522. Because lug 526 is fixed in the axial direction due to the disposition of ring 524
within a slot of housing cylindrical portion 508a, the action of lug 526 in first position
534a on the outer wall of slot 522 prevents piston 510 from axial movement in the
direction of first port 114.
Piston 510 in the first position, restrained from further axial movement in the
10 direction of fifth port 504, provides a sealing engagement between outer flanged
portion 510c and seal 516 of flange 514. This sealing engagement prevents a fluid
flow from fifth port 504 through chamber 542 and into internal passageway 102a of
pipe 102 through fourth port 502. Thus, flow from wellbore 12 may only enter
internal passageway 102a through flow restrictor portion 500a.
15 Referring now to FIGS. 5B and 6, in order to seal the internal passageway
102a from wellbore 12, a well system operator pumps fluid at high pressure from the
surface of the well system into internal passageway 102a, creating an internal
differential pressure where the pressure within passageway 102a of pipe 102 is higher
than the pressure of fluid within the wellbore 12 surrounding pipe 102. This internal
20 pressure differential establishes flow path 530, where fluid enters flow restrictor
portion 500a through first port 114 and third port 118, providing a pressure force on
first side 106e, second side 106f and third side 106g of piston 106. This pressure
force produces a net force on piston 106 in the direction of second port 120, with a
predetermined magnitude so as to shear the shear member 116, providing for sealing
25 engagement between upper flanged portion 106c and seal 112 of flange 110.
Further, this pressure force, providing a larger force than the directlonallyopposed
force produced by biasing member 520, actuates the J-Slot 702 mechanism.
The pressure force may be predetermined, in that it may be calculated what pressure
within internal passageway 102a is necessary to provide for a pressure force on the
30 first face 540 of piston 510 to defeat the biasing force created by biasing member 520.
Now forcibly compelled in the axial direction of biasing member 520.
23
opposite the direction of fifth port 504, piston 510 is free to axially slide in the
direction of biasing member 520 until lug 526 reaches its second position 534b, shown
by FIG. 6. After axial movement in the direction of biasing member 520 by piston
510, lug 526 comes into contact with the outer wall of slot 522 as it reaches second
5 position 534b, restraining piston 510 from further axial movement in the direction of
biasing member 520. In this second position, outer flanged portion 51 Oc of piston 510
remains in sealing engagement with seal 516 of flange 514. Thus, flow restrictor
portion 500a and bypass valve portion 500b both seal internal passageway 102a from
wellbore 12.
10 Following the shearing of shear member 116 and the moving of piston 510
into its second position, a well system operator may reduce the pressure within
internal passageway 102a by stopping any pumping into passageway 102a, in order to
shut-in the well for abandonment purposes or to perform downhole work. Referring
now to FIG. 5C and 6, the reduction of pressure within internal passageway 102a
15 eliminates or substantially decreases the internal pressure differential, allowing the
biasing member 520 to overcome any present pressure forces on piston 510 and
actuate the piston. The actuation of piston 510 returns it to its original position and
positions lug 526 into a third position 534c (FIG. 6). Now in third position 534c, the
lug 526 acting on the outer wall of slot 522 restrains piston 510 from further axial
20 movement in the direction of fifth port 504, thus maintaining sealing engagement
between outer flanged portion 510c and seal 516 of flange 514.
Referring again to FIGS. 5B and 6, in order to move piston 510 into a third
position, a well system operator first creates a second internal pressure differential,
such as illustrated in FIG. 5B. Regarding flow restrictor portion 500a, piston 106,
25 having already been actuated by the first internal pressure differential, remains in its
second position with upper flanged portion 106c sealing against seal 112 of flange
110.
Regarding bypass valve portion 500b, piston 510 is again actuated into its
second position with the pressure force acting on second face 540 leading to a net
30 force on piston 510 in the direction of biasing member 520. The movement of piston
510 into its second position actuates the J-Slot mechanism, moving lug 526 into its
24
fourth position 534d, illustrated in FIG. 6. After actuation of piston 510, lug 526
comes into contact with the outer wall of slot 522 and thus comes to rest in its fourth
position 534d, preventing any further axial movement by piston 510 in the direction of
biasing member 520.
5 Referring now to FIGS. 5D and 6, following the creation of the second internal
differential pressure, a well system operator reduces pressure within internal
passageway 102a of pipe 102, creating an external differential pressure where the fluid
within wellbore 12 has a higher pressure than fluid within internal passageway 102a.
The external differential pressure creates flow path 532, with fluid entering flow
10 control device 500 through fifth port 504 and exiting into internal passageway 102a
through fourth port 502. Also, the external differential pressure actuates J-Slot 522,
moving piston 510 into a third position, illustrated in Figure 5D.
While piston 510 is restrained from axial movement in the direction of biasing
member 520 while lug 526 is in fourth position 534d (FIG. 6), piston 510 is free to
15 slide axially in the direction of fifth port 504. The external pressure differential
reduces the pressure force acting on second face 540 of piston 510, allowing the
biasing member 520 to forcibly compel piston 510 in the direction of fifth port 504.
Also, sixth port 506 allows for fluid communication between fluid within wellbore 12
and first face 538 of piston 510, thus equalizing any pressure forces acting on piston
20 510. With lug 526 in fourth position 534d, piston 510 slides axially in the direction of
fifth port 504, positioning lug 526 in fifth position 534e (FIG. 6), wherein the outer
wall of slot 522 prevents piston 510 from any ftirther axial movement in the direction
of fifth port 504.
Now in a third position, outer flanged portion 510c is no longer in sealing
25 engagement with seal 516 of flange 514, resulting in a gap 544. Fluid along flow path
532 may thus flow through gap 544 and enter internal passageway 102a through
fourth port 502. Also, flow path 532 does not flow through flow restrictor 164 of flow
restrictor portion 500a, resulting in a second, smaller pressure drop of fluid in flow
path 532 as it flows into internal passageway 102a fi-om wellbore 12.
30 A method for controlling fluid flow into a pipe may comprise producing fluid
through a flow restrictor disposed in a first flow path, substantially sealing the first
25-
flow path in response to a first pressure, establishing a second flow path in response to
a second pressure, and producing fluid through the second flow path. Substantially
sealing the first flow path may comprise applying a first pressure to the flow restrictor
and to a piston that is disposed in a first position, causing the piston to move from the
5 first position to a second position, the second position sealing fluid from flowing
through the flow restrictor and into the pipe along the first flow path. Also,
establishing a second flow path may comprise applying a second pressure greater than
the first pressure to a valve that, when closed, prevents fluid flow into the pipe, the
application of the second pressure causing the valve to open and allow fluid flow to
10 pass through the valve into the pipe through a second flow path.
While specific embodiments have been shown and described, modifications
thereof can be made by one skilled in the art without departing from the scope or
teachings herein. The embodiments described herein are exemplary only and are not
limiting. Many variafions and modifications of the systems, apparatus, and processes
15 described herein are possible and are within the scope of the invention. For example,
the relative dimensions of various parts, the materials from which the various parts are
made, and other parameters can be varied. For instance, various designs of flow
restrictors may be incorporated into the flow control device 100 illustrated in FIG. 2,
such as orifice plates, helical tubes, U-Bend restrictors, nozzles, etc. Additional
20 details concerning these additional flow restrictor designs are disclosed in U.S. Patent
Publication No. 2009/0151925, the entire disclosure of which is incorporated herein
by this reference. Accordingly, the scope of protection is not limited to the
embodiments described herein, but is only limited by the claims that follow, the scope
of which shall include all equivalents of the subject matter of the claims.
25
26

WE CLAIM:
1. A flow control device comprising:
a tubular member having an interior passageway for conveying fluids;
a housing disposed about the tubular member and forming a chamber
5 between the housing and the tubular member, wherein the housing is
divided into a control chamber and a valve chamber;
a piston disposed within the control chamber and moveable between a first
piston position and a second piston position that is displaced from the
first piston position, wherein the piston divides the control chamber
10 into first and second portions; and
a valve disposed within the valve chamber and moveable between a first
valve position and a second valve position that is displaced from the
first valve position, wherein the valve provides for selective fluid
communication between a first portion of the valve chamber and a
15 second portion of the valve chamber,
wherein the piston provides a first fiow path between the control chamber
and interior passageway of the tubular member in the first piston
position, and
wherein the valve provides a second flow path between the valve chamber
20 and interior passageway of the tubular member in the second valve
position.
2. A flow control device as claimed in claim 1, further comprising a valve
retaining member, wherein the retaining member comprises a shear member that is
configured to shear in response to a first pressure being applied to the valve.
25 3. A flow control device as claimed in claim 1, further comprising a valve
retaining member, wherein the retaining member comprises a J-slot mechanism that
is configured to actuate in response to a second pressure being applied to the valve.
4. A flow control device as claimed in claim 1, wherein the valve comprises a
collet and valve plug assembly.
30 5. A flow control device as claimed in claim 1, wherein the valve comprises a
piston and flange assembly.

6. A flow control device as claimed in claim 1, further comprising a flow
restrictor disposed in the first portion of the control chamber, wherein fluid flow
along the first flow path through the control chamber results in a pressure drop.
7. A flow control device as claimed in claim 1, wherein the valve provides for
5 fluid communication between the first portion of the valve chamber and the second
portion of the valve chamber when the valve is disposed in the second position.
8. A flow control device as claimed in claim 1, wherein the piston, when
disposed in the second position, and the valve, when disposed in the first position,
provides a seal against fiuid communication with the interior passageway of the
10 tubular member.
9. A flow control device for control of fluid flow through a tubular member
comprising:
a control chamber having a piston disposed therein, wherein the piston is
moveable from an open piston position to a closed piston position by
15 the application of a first fluid pressure; and
a valve chamber having a valve therein, wherein the valve is moveable from
a closed valve position to an open valve position by the application of
a second fluid pressure;
wherein a seal preventing fluid flow through the control chamber into the
20 tubular member is formed in the closed piston position, and
wherein a flow path through the valve chamber and into the tubular member
is formed in the open valve position.
10. A flow control device as claimed in claim 9, further comprising a restraining
member configured to be actuated by movement of the piston in response to the first
25 fluid pressure.
11. A flow control device as claimed in claim 9, fijrther comprising a restraining
member configured to be actuated by movement of the valve in response to the
second fluid pressure.
12. A flow control device as claimed in claim 9, wherein the valve forms a seal
30 against a fluid flow between at least a portion of the valve chamber and the tubular
member during the application of the first fluid pressure.

13. A flow control device as claimed in claim 9, wherein a first flow path
through the control chamber into the tubular member creates a first pressure drop,
wherein a second flow path through the valve chamber into the tubular member
creates a second pressure drop, and wherein the second pressure drop is less than the
5 first pressure drop.
14. A flow control device as claimed in claim 9, wherein the second fluid
pressure is greater than the first fluid pressure.
15. A flow control device as claimed in claim 9, further comprising a flow
restrictor disposed within the control chamber, wherein the flow restrictor is
10 configured to provide a helical flow path.
16. A flow control device as claimed in claim 9, further comprising a nozzle
disposed within the control chamber.
17. A method for controlling flow into a tubular member comprising:
providing fluid communication between an interior of the tubular member
15 and a subterranean formation along a first flow path;
substantially sealing the first flow path in response to a first pressure;
establishing a second flow path between the interior of the tubular member
and the subterranean formation in response to a second pressure: and
providing fluid communication between the interior of the tubular member
20 and the subterranean formation along the second flow path.
18. A method as claimed in claim 17, wherein substantially sealing the first flow
path comprises applying a first pressure to a flow restrictor disposed in the first flow
path and to a piston that is disposed in a first position, translating the piston from the
first position to a second position in response to the first pressure, and substantially
25 sealing fluid flow through the flow restrictor and into the interior of the tubular
member along the first flow path.
19. A method as claimed in claim 17, wherein establishing a second flow path
comprises applying a second pressure greater than the first pressure to a valve,
actuating the valve from a closed position to an. open position in response to the
30 second pressure, and flowing fluid through the valve into the interior of the tubular
member through a second flow path.

20. A method as claimed in claim 17, wherein the first flow path is substantially
sealed prior to establishing the second flow path.