FIELD OF INVENTION
This invention relates to apparatus, systems and methods for bypassing a flow
control device. The disclosure relates generally to equipment utilized and operations
performed in conjunction with a subterranean well and, more particularly, to the application
5 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, as an
10 example.
During the production of hydrocarbons from a subterranean well, it was desirable to
substantially reduce or exclude the production of water produced from the well. For
example, it is desirable for the fluid produced from the well to have a relatively high
proportion of hydrocarbons, and a relatively low proportion of water. In some cases, it is
15 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 conformance, thereby increasing
the proportion and overall quantity of oil produced from the interval. Inflow control
20 devices (ICDs) have been used in the past to restrict flow of produced fluid through the
ICDs for this 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."
25
SUMMARY OF INVENTION
In an embodiment, a bypass assembly for use in a downhole tool comprises a
chamber, a first fluid port in fluid communication with the chamber, a second fluid port in
fluid communication with the chamber, a flow restrictor disposed in a first flow path
2-
between the first fluid port and the second fluid port, a piston moveable in a first direction
by the application of a first fluid pressure, a biasing member, and a restraining member
disposed adjacent to the piston. The biasing member biases the piston to move in a second
direction opposite the first direction, and the restraining member is actuated by movement
5 of the piston in the first direction in response to a predetermined fluid pressure. Movement
of the piston in the second direction to a predetermined position configures the bypass
assembly to divert fluid flow around the flow restrictor along a second flow path.
In an embodiment, a flow control device for use in a downhole tool comprises a
flow restriction disposed in a first flow path between a first port and a second port, and a
10 bypass mechanism configured to be moveable between a first position and a second
position in response to a first pressure. The first flow path between the first port and the
second port is established when the bypass mechanism is in the first position, and a second
flow path between the first port and second port is established when the bypass mechanism
is in the second position.
15 In an embodiment, a method for bypassing a flow restrictor comprises flowing a
fluid through a first flow path between a first port and a second port, where the first flow
path comprises a flow restrictor, translating a moveable element in response to a pressure
applied to the moveable element, where the translating the moveable element opens a
second flow path between the first port and the second port, and flowing a fluid through the
20 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.
25 BRIEF DESCRIPTION OF THE DRAWINGS
For a detailed description of the apparatus, systems and methods disclosed herein,
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.
-3
Figure 2A is a cross-sectional view of an embodiment of a flow control device in a
first position.
Figure 2B is a cross-sectional view of an embodiment of a flow control device in a
second position.
5 Figure 2C is a cross-sectional view of an embodiment of a flow control device in a
third position.
Figure 3 is a cross-sectional view of an embodiment of a flow control device
including a nozzle flow restrictor.
Figure 4 is a cross-sectional view of an embodiment of a flow control device
10 including a u-bend flow restrictor.
Figure 5 is a cross-sectional view of an embodiment of a flow control device
including an aimular flow tube flow restrictor.
Figure 6 is a cross-sectional view of an embodiment of a flow control device
including a helical flow tube flow restrictor.
15 Figure 7A 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 position.
Figure 7B is a cross-sectional view of the flow control device of Figure 7A with the
J-Slot mechanism shown in a second position.
Figure 7C is a cross-sectional view of the flow control device of Figure 7A with the
20 J-Slot mechanism shown in the third position.
Figure 8 is a top view of the J-Slot shown in Figures 7A-7C.
Figure 9 is an isometric view of an embodiment of a lug ring for the J-Slot
mechanism of Figures 7A-7C.
DESCRIPTION OF INVENTION w.r.t. DRAWINGS
25 It should be understood at the outset that although illustrative implementations 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
-4
implementations, drawings, and techniques illustrated below, but may be modified 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
5 features and components herein may be shown exaggerated in scale or in somewhat
schematic form and some details of conventional elements may not be shown in the 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
10 meant to limit the interaction to direct interaction between the elements and may also
include indirect interaction between the elements described. In 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,"
15 "upward," or "uphole" meaning toward the surface of the wellbore and with "down,"
"lower," "downward," or "downhole" meaning toward 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
20 horizontally and/or vertically spaced portions of the same formation. The various
characteristics mentioned above, as well as other 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.
25 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, plurality of spaced apart packers 22 and
flow control devices 24, and a formation 26.
5-
Production of hydrocarbons may be accomplished by flowing fluid containing
hydrocarbons from the formation 26, into horizontal section 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 material from the formation 26 and for the
5 metering of fluid input from the formation into the tubular string 20. Packers 22 can 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
increased fluid pressure loss in the uphole section of the tubular string 20 disposed in the
10 horizontal section 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 of
the metering capability of each fluid control device 24 to result in a more even flow rate
15 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
horizontal section 16, it is to be understood that the flow control devices are equally suited
20 for use in cased wellbores. For instance, the flow control devices 24 and packers 22 may
be used for flow control purposes when injecting treatment chemicals, such as acids, into
the perforations of a cased wellbore. Further, although FIG. 1 depicts single flow control
devices 24 as being isolated by the packers 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
25 departing from the principles of the present disclosure. In addition, even though FIG. 1
depicts the flow control devices 24 in a horizontal section 16, it is also to be understood
that the flow control devices are equally suited for use in wellbores having other directional
configurations including vertical wellbores, deviated wellbores, slanted wellbores,
multilateral wellbores and the like.
6-
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 to maximize
production. Thus, while ICDs may be 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
5 order to extract any remaining hydrocarbons from the surrounding formation. Accordingly,
an apparatus and method are disclosed herein for quickly and efficiently bypassing the
ICDs after they have been installed downhole in the well without the need for physically
intervening into the well.
While a number of mechanisms may be used, it will be appreciated that a flow
10 control device may comprise a bypass assembly for use in a downhole tool that may be
used to bypass a flow restriction such as an ICD. The bypass assembly may comprise a
moveable element that may be configured to move in response to the application of a first
fluid pressure inputted from the second port. The bypass assembly may also comprise a
restraining member configured to restrain the moveable element from actuating until a
15 predetermined fluid pressure above a threshold is applied to the moveable element. The
movement of the piston to a predetermined position may divert fluid flow around the flow
restriction along a second flow path, thereby allowing for the flow restriction to be
bypassed without requiring a mechanical intervention in the well. In an embodiment, the
second flow path may have a smaller pressure drop in a fluid flow between the first port
20 and the second port. Thus the bypass assembly may be configured to allow fluid to be
produced along a first flow path, translate a moveable element in response to a fluid
pressure, and thereafter produce the fluid along a second flow path. Similarly, the bypass
assembly may be configured to produce a fluid with a first pressure drop, translate a
moveable element in response to a fluid pressure, and thereafter produce the fluid with a
25 second pressure drop that is different than the first pressure drop.
In an embodiment, a plurality of the flow control devices comprising bypass
assemblies may be used with a plurality of flow restrictions disposed in a wellbore. In this
embodiment, one or more of the bypass assemblies may be configured to actuate a
moveable element in response to the application of a first pressure above a threshold. The
7-
one or more bypass assemblies may be configured to translate a moveable element and
prevent fluid flow through the bypass assembly while the first pressure is maintained, fhis
may allow all of the bypass assemblies to be actuated along the length of a wellbore until
the pressure is thereafter reduced and the bypass assemblies are reconfigured to divert the
5 fluid flow around the flow restriction along a second flow path. While only a portion of the
bypass assemblies may actuate in response to the first pressure above a threshold, one or
more additional bypass assemblies may be actuated in response to a second pressure above
a threshold, where the second pressure is greater than the first pressure.
Referring now to FIG. 2A, 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
pipe or tubular member 102, a filter 104, a first port 106, a housing 108, a flow restrictor
110 with a fluid passage 112, a piston 114 with a first side 116 and a second side 118, a
shear member 124, and a biasing member 126.
15 The tubular member 102 comprises any tubular member capable of being used
downhole and communicating fluid at high pressures. The tubular member 102 forms a
portion of the tubular string 20 described above with reference to FIG 1 that can be
bypassed. The tubular member 102 includes an internal fluid passageway 102a, through
which fluids may be conveyed in both uphole and downhole directions, and at least one
20 radially directed second port 122 that extends through the wall of the tubular member 102.
The housing 108 comprises an annular member disposed about the tubular member
102 forming aimular chamber 108c, and includes a cylindrical outer portion 108a and a
flanged portion 108b extending radially therefrom and fixed to the outer surface of the
tubular member 102. Together, the outer portion 108a and the flange 108b define a
25 chamber 108c between the housing 108 and the tubular member 102. A third port 128
provides for fluid communication between the wellbore 12 and the chamber 108c.
Opposite flange 108b and adjacent to filter 104 is internal flange 108d that extends radially
into chamber 108c fi-om outer portion 108a and, as described in more detail below, defines
a portion of the first port 106.
8-
The flow restrictor 110 is an annular member that is disposed about the tubular
member 102. In this embodiment, the restrictor 110 has an elongated tubular portion 110a
and a flanged portion 11 Ob that extends radially from tubular portion 110a. The portion
110a is fixed to the tubular member 102. The radially outermost surface of the flanged
5 portion 110b includes a groove 110c in which an annular seal 120a is retained. Also in this
embodiment of the flow restrictor 110, at least one fluid passage 112 extends in an axial
direction through tubular portion 11 Oa.
The piston 114 is another member disposed about the tubular member 102 and
adapted for sliding engagement relative to the housing 108 and the tubular member 102.
10 The piston 114 includes an elongated outer portion 114a, a lower flanged portion 114b, and
an upper flanged portion 114c opposite the lower flanged portion. The lower flanged
portion 114b extends inwardly from the outer portion 114a and retains annular seals 120b
and 120c, which sealingly engage the inner surface of the housing 108 and outer surface of
the tubular member 102, respectively. The lower flanged portion 106b also includes a first
15 side 116 disposed adjacent to the second port 122 and a second side 118 disposed adjacent
to the shear member 124. The upper flanged portion 114c includes an inwardly facing
sealing surface for sealingly engagement with the seal 120a retained in the groove 110c of
the flow restrictor 110. The annular seals 120b and 120c divide the chamber 108c into two
portions, with one portion containing the first port 106, flow restrictor 110, second port 122
20 and first side 116 of the piston, and the other containing the shear member 124, biasing
member 126, and third port 128.
In this embodiment, the shear member 124 is a pin disposed in the chamber 108c
and extending into the wall of the tubular member 102. Shear member 124 is positioned in
between the second side 118 of the piston 114 and the biasing member 126. The
25 longitudinal axis of the shear member 124 is perpendicular to the longitudinal axis of the
tubular member 102. Further, the shear member 124 is fixed within a bore 124a in the
tubular member 102.
The biasing member 126 may comprise a compression spring disposed about the
tubular member 102 in the chamber 108c and is initially restrained from movement in a
-9
compressed state by shear member 124. Furthermore, the biasing member 126 produces a
biasing force against the shear member 124. The shearing member 124 and the biasing
member 126 are designed such that the shearing member can withstand the biasing force
without shearing. Also, although FIG. 2B depicts the biasing member 126 to be a spring,
5 any suitable biasing mechanism may be used to provide a force to the piston 114 as
described herein, such as disc springs, torsion springs, gas springs, elastomeric members
and the like.
During normal operation when producing hydrocarbons via a well system, the
pressure within tubular member 102 will be lower than the pressure of fluid within a
10 surrounding formation 26. At this fime, the piston 114 is disposed in a first position shown
in Figure 2A where the second side 118 acts on the shear member 124 and the upper
flanged portion 114c is sealingly engaged with the seal 120a of the flow restrictor 110. In
this configuration, due to this differential pressure, a flow path 130 is established where
fluid from a surrounding formation enters the filter 104 in order to remove at least a portion
15 of any entrained sand or other debris and particulates. The filter 104 illustrated in FIG. 2A
is a type known as "wire-wrapped," where wire is closely wrapped helically about tubular
member 102, with the spacing between each windings of wire designed to allow the
passing of fluid but not of sand or other debris larger than a certain size. Other types of
filters may also be used, such as sintered, mesh, pre-packed, expandable, slotted, perforated
20 and the like.
Following filtration, fluid enters the flow control device 100 through first port 106
and then passes through fluid passage 112 of flow restrictor 110, which creates a pressure
drop between fluid entering the flow restrictor and fluid exiting the flow restrictor. The
fluid passing along flow path 130 is prevented from flowing around or bypassing the flow
25 restrictor 110 due to the seal 120a located on the flow restrictor which seals the engaging
surfaces of the flow restrictor 110 and the piston 114. Having exited the flow restrictor
110, the fluid then follows flow path 130 through second port 122 and into the tubular
member 102. The fluid in flow path 130 is prevented fi-om flowing around the piston 114
and out of the third port 128 by the annular seals 120b, 120c disposed on the piston and
10
sealingly engaging surfaces between the piston 114 and the housing 108 and between the
piston and the tubular member 102.
In this particular embodiment, the flow restrictor 110 is a cylindrical flow tube with
at least one through passage 112 extending generally parallel to its longitudinal axis and
5 having a diameter that is substantially smaller than the axial length of the flow restrictor
110. This long, slender bore of the fluid passage 112 produces a flow restriction resulting
in a pressure drop in the fluid flowing through it. Also, the diameter and length of this fluid
passage 112 may be adjusted prior to installation of the flow control device 100 in order to
achieve the desired amount of flow restriction. Although FIG. 2A illustrates a flow control
10 device 100 with a flow tube type flow restrictor 110, other flow restrictor designs, such as
described below, may be used in conformance with the principles set forth in this
disclosure.
Referring again to FIG. 1, at a certain time during the production of hydrocarbons,
it may be advantageous to bypass the flow restrictor 110 of the flow control device 100 in
15 order to allow for a higher fluid flow rate to enter the tubular string 20 from a surrounding
formation. For instance, a imiform 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 20
from the formation 26. Once a well system 10 has begim producing water or gas from the
formation 26, the advantage of a uniform metered flow from flow control devices 24 is
20 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 in order to increase the How rate
entering the tubular string 20 from the formation 26.
Referring now to FIG. 2B, the flow control device 100 is provided with a bypass
25 mechanism configured to allow the flow control device to lessen the flow restrictions (and
thereby increase fluid intake) by introducing a pressure signal into tubular member 102.
More particularly, internal fluid passageway 102a of tubular member 102 may be
pressurized such that the fluid pressure within the tubular member 102 is higher than the
pressure of the fluid in the surrounding formation 26. This increase in pressure results in a
11
flow of fluid along reverse flow path 132. Fluid in flow path 132 moves from the internal
fluid passageway 102a into the chamber 108c through the second port 122 formed in
tubular member 102. From there, fluid flows into the fluid passage 112 of flow restrictor
110. Following there, the fluid moving in flow path 132 exits chamber 108c by passing
5 through filter 104 and entering the wellbore 12 (illustrated in FIG. 1).
However, due to the pressure drop created by the flow restrictor 110, the pressure
of the fluid entering the flow restrictor 110 is higher than the pressure of the fluid exiting
the flow restrictor. Thus, a pressure force from the fluid entering chamber 108c via the
second port 122 is applied to the first side 116 of flanged portion 114b of the piston 114.
10 This pressure forces the piston 114 to move in a first direction against the shear member
124, which shears at a predetermined force in response to the shearing force applied by the
piston 114 created by pressurizing the fluid in tubular member 102. The shear member 124
may be configured to shear at a known applied force, such the amount of pressure needed
to be applied to the fluid in the tubular member 102 may be calculated so an operator of the
15 well system will know approximately what pressure must be applied to the tubular member
102 for the shearing member 124 to be sheared.
Upon shearing of the shear member 124, the piston 114 applies a force against the
biasing member 126. The pressure force from the fluid entering second port 122 will
counteract the biasing force produced by the biasing member 126, forcing the biasing
20 member to compress. The fluid surrounding the biasing member 126 does not provide a
pressure force in response to the axial movement of the piston 114 due to the third port 128,
which allows it to escape into the wellbore 12.
Even though the shearing member 124 has been sheared and thus the piston may be
allowed to move axially in the direction of the biasing member 126 (left-to-righl as
25 depicted in FIG. 2B), the seal 120a between the flow restrictor 110 and the piston 114
prevents against any fluid in the flow path 132 from deviating around the flow restrictor.
Thus, there is no path of least resistance for the higher pressure fluid within the tubular
member 102 to escape, forcing the shear members 124 in all of the flow control devices
100 disposed on the tubular member 102 to shear. This is to be distinguished from the
12
conventional use of rupture disks in flow control devices used in a production string
because, once the first rupture disk has burst in one of the flow control devices, fluid is
allowed to bypass the flow restrictor, and thus a path of least resistance is provided for the
higher pressure fluid, preventing bursting of the rupture disks in the other flow control
5 devices disposed along a production string.
Referring now to FIG. 2C, following the shearing of the shear member 124 of the
flow control device 100, an operator will reduce the pressure within the tubular member
102 until a pressure differential is created in which there is a higher pressure in the fluid of
a formation 26 surrounding the flow control device 100 and a lower pressure in the tubular
10 member 102. The reduced pressure in the tubular member 102 results in a reduction of
pressure and thus a reduced force acting on the first side 116 of the piston 114. The
reduced force acting on the first side 116 is offset by the biasing force produced by the
biasing member 126. The larger biasing force acts on the second side 118 of the piston,
forcing the piston to move axially in a second direction towards the flow restrictor 110,
15 creating an annular gap 138 between the flow restrictor and the piston 114, as the piston
comes to rest in a second position as shown in FIG. 2C.
Given the reduction in pressure of the fluid in the tubular member 102, a second
flow path 134 results. Fluid passing along second flow path 134 first enters the fiher 104
and flows into the flow control device 100 through the first port 106. Following this, the
20 fluid in the flow path 134 flows around the flow restrictor 110, through gap 138 that is
formed between the piston 114 and the flow restrictor 110. Then, the fluid in flow path 134
is directed through the second port 122 and into the internal fluid passageway 102a of
tubular member 102. Allowing the flow path 134 to deviate around the flow restrictor 110
and, in this embodiment, to bypass the small diameter fluid passage 112, provides a path
25 with a substantially larger cross-sectional area for fluid to flow through, providing for less
restriction for the flow and a smaller pressure drop between the fluid entering the first port
106 and the fluid exiting the second port 122. Thus, by creating and employing a less
restrictive flow path 134, a higher flow rate of fluid from formation 26 may be produced
through the flow control device 100 as compared to the first flow path 130 of FIG. 2 A.
- 1 3 -
To further illustrate various illustrative embodiments of systems, methods and tools
for bypassing flow control devices, the following additional embodiments are provided.
Referring to FIG. 3, in this embodiment of a flow control device 300, a nozzle 302
is fixed to the tubular member 102. The nozzle 302 includes a central orifice 304 for the
5 creation of a pressure drop in a fluid flow passing through the nozzle 302. The seal 120a
disposed in a groove of the nozzle 302 acts to create a seal between the upper flange 114c
of the piston 114 and the nozzle 302. The operation of flow control device 300 is
substantially the same as that described above with reference to flow control device 100.
Referring to FIG. 4, in this embodiment of a flow control device 400, a U-Bend
10 flow restrictor 402 is disposed about the tubular member 102. The U-Bend restrictor
includes a flanged portion 402a that is fixed to the tubular member 102. The U-Bend
restrictor 402 also includes a U-Bend portion 402c configured to induce a pressure drop in
a fluid flowing through the U-Bend portion 402c. Both the U-Bend portion 402c and
flanged portion 402a include a central through passage 402b for the passing of a fluid flow.
15 The operafion of flow control device 400 is substantially the same as that described above
for flow control device 100.
Referring to FIG. 5, in this embodiment of a flow control device 500, an annular
flow tube 502 is fixed to the outer circumference of the tubular member 102. The annular
tube 502 contains a solid cylindrical body 502a disposed within a tube 504. A fluid flow
20 may be established in the annulus between the tube 504 and cylindrical body 502a. with the
thin annulus resulting in a pressure drop in the fluid flow. The annular flow tube also
contains a flanged portion 502b that retains the flow restrictor seal 120a. The flow
restrictor seal 120a sealingly engages the upper flange 114c, forcing any fluid flow between
the first port 106 and the second port 122 to flow through the annular flow tube 502. The
25 operation of flow control device 500 is substantially the same as that described above for
flow control device 100.
Referring to FIG. 6, in this embodiment of a flow control device 600. a helical flow
tube 602 is fixed to the outer circumference of the tubular member 102. The helical flow
tube 602 includes a cylinder 602a with a helical flow path 602c bored near the radial ends
14
of the cylinder 602a. A fluid flow may be established through the helical flow path 602c,
resulting in a pressure drop in the fluid as it flows through the helical flow tube 602. The
helical flow tube 602 also includes a flanged portion 602b that houses the flow restrictor
seal 120a, which sealingly engages the upper flange 114c of the piston 114, thus directing
5 fluid through the helical flow tube 602. The operation of flow control device 600 is
substantially the same as that described above for flow control device 100. Additional
details concerning the flow restrictors 300, 400, 500 and 600 are disclosed in U.S. Patent
Application No. 2009/0151925, the entire disclosure of which is incorporated herein by this
reference.
10 With reference to Figures 2A - 6, a shearing member 124 was described above that
served as a restraining mechanism or releasable latch that prevents axial movement of
piston 114 towards the biasing member 126 until a pressurization of predetermined
magnitude caused the piston to shear the shearing member 124, thereby freeing the piston
to be moved axially by means of the biasing member. Other releasable latches or
15 restraining mechanisms can likewise be employed, including those that do not require the
shearing of frangible members. For example, and referring now to FIG. 7A, another type of
restraining mechanism is disclosed as employed in flow control device 700. More
specifically, the restraining mechanism employed in flow control device 700 is a J-Slot
mechanism. In this embodiment, an irregularly shaped J-Slot 702 is disposed within a top
20 surface 136 of piston 114. A ring 704 is disposed within a slot in the wall 108a of housing
108 and about tubular member 102. Ring 704 is fixed axially by housing 108 but is free to
rotate within housing 108 and about piston 114. Fixed to ring 704 is a radially-extending
lug 706, disposed within a portion of slot 702. Lug 706 restricts the degree of rotation
afforded ring 704 due to contact between lug 706 and the outer walls of slot 702.
25 FIG. 8 illustrates the top surface 136 of piston 114. Disposed within the top surface
136 is the irregularly shaped J-Slot 702, and within slot 702 is disposed lug 706. Lug 706,
depending on the position of piston 114, may translate between three different positions of
slot 702: a first position 708, a second position 710, and a third position 712. FIG. 8 is
shown oriented such that the bottom part of FIG. 8 is axially proximal to the biasing
-15-
member 126 (FIG. 7A) and the top part of FIG. 8 is proximal to the first port 106 (FIG.
7A). FIG. 9 illustrates the shape of ring 704 and lug 706, as they are configured in the flow
control device 700.
Referring to FIG. 7A, flow control device 700 is shown in a production state where
5 an external pressure differential results in flow path 130, wherein fluid from wellbore 12
enters flow control device 100 through first port 106, flows through flow restnctor 110, and
into internal fluid passageway 102a of tubular member 102 through second port 122.
Piston 114 occupies a first position where second face 118 of piston is acted upon by
biasing member 126. Biasing member 126 produces a force on piston 114 in the direction
10 of first port 106. However, piston 114 is axially restrained from movement in the direction
of first port 106 due to contact between lug 706 and slot 702. Referring to FIGS. 7A and 8,
while piston 114 occupies this first posifion, lug 706 occupies first position 708 (FIG. 8),
and is in contact with the outer wall of slot 702. Because lug 706 is fixed in the axial
direction due to the disposifion of ring 704 within a slot of housing wall 108a, the
15 engagement of lug 706 in first position 708 with the outer wall of slot 702 prevents piston
114 from axial movement in the direction of first port 106.
Piston 114 in the first position, thus restrained from further axial movement in the
direction of first port 106, provides a sealing engagement between upper flanged portion
114c and seal 120a of flow restrictor 110. This sealing engagement forces fluid along flow
20 path 130 to flow through flow restrictor 110, creafing a pressure drop, before entering
second port 122.
Referring now to FIGS. 7B and 8, in order to move piston 114 into a second
position, a well system operator pumps fluid at high pressure from the surface of the well
system into internal fluid passageway 102a, creating an internal differential pressure where
25 the pressure within internal fluid passageway 102a of tubular member 102 is higher than
the pressure of fluid within the wellbore 12 surrounding tubular member 102. This internal
pressure differential establishes flow path 132, where fluid enters chamber 108c through
second port 122, providing a pressure force on first face 116 of piston 114. This pressure
force, providing a larger force than the directionally-opposed force produced by biasing
16
member 126, actuates the J-Slot 702 mechanism. The pressure force may be
predetermined, in that the pressure within internal fluid passageway 102a necessary to
provide for a pressure force on the first face 116 of piston 114 to defeat the biasing force
created by biasing member 126 may be calculated.
5 Now forcibly compelled in the axial direction of biasing member 126, opposite the
direction of first port 106, piston 114 is free to axially slide in the direction of biasing
member 126 until lug 706 reaches its second position 710, shown by FIG. 8. After axial
movement in the direction of biasing member 126 by piston 114, lug 706 comes into
contact with the outer wall of slot 702 as it reaches second position 710, restraining piston
10 114 from further axial movement in the direcfion of biasing member 126. In this second
position, upper flanged portion 114c of piston 114 remains in sealing engagement with seal
120a of flow restrictor 110.
Referring now to FIGS. 7C and 8, in order to move piston 114 into a third position,
a well system operator reduces pressure within internal fluid passageway 102a of tubular
15 member 102, creating an external differential pressure where the fluid within wellbore 12
has a higher pressure than fluid within internal fluid passageway 102a. The external
differential pressure creates flow path 134, with fluid entering flow control device 700
through first port 106 and exiting into internal fluid passageway 102a through second port
122. Also, the external differential pressure actuates J-Slot 702, moving piston 114 into a
20 third position shown in Figure 7C.
While piston 114 is restrained from axial movement in the direction of biasing
member 126 while lug 706 is in second position 710 (FIG. 8), piston 114 is free to slide
axially in the direction of first port 106. The external pressure differential reduces the
pressure force acting on first face 116 of piston 114, allowing the biasing member 126 to
25 forcibly compel piston 114 in the direction of first port 106, With lug 706 in second
position 710, piston 114 slides axially in the direction of first port 106, positioning lug 706
in third position 712 (FIG. 8), wherein the outer wall of slot 702 prevents piston 114 from
any further axial movement in the direction of first port 106.
17
Now in a third position, upper flanged portion 114c is no longer in sealing
engagement with seal 120a of flow restrictor 110, resulting in a gap 138. Fluid along flow
path 134 may thus bypass flow restrictor 110, flow through gap 138, and enter internal
fluid passageway 102a through second port 122. Bypassing flow restrictor 110 results in a
5 second, smaller pressure drop of fluid in flow path 134 as it flows into internal fluid
passageway 102a from wellbore 12. Further, instead of having ring 704 rotate, lug 706
may be fixed to housing 108 and the piston 114 may then rotate due to the interaction
between lug 706 and the outer wall of slot 702.
In an embodiment, a method for bypassing a flow restrictor may comprise flowing
10 a fluid through a first flow path from a first port to a second port, translating a component
from a first position to a second posifion in response to a pressure differential, and flowing
a fluid through a second flow path from the first port to the second port. The method may
also include flowing a fluid through a third flow path from the second port to the first port,
wherein the aforementioned pressure differential is created by the fluid flowing through the
15 third flow path.
In an embodiment, another method for producing hydrocarbons from a well system
may comprise flowing a fluid from a formation into an internal passageway of a production
string. As the fluid enters the production string, it flows through a filter and an ICD to
create a pressure drop in the fluid flow as it enters the internal passageway. After a period
20 of producing fluid from the formation, fluid may be pumped into the production string from
the surface, such as to create an internal pressure differential where the pressure within the
internal passageway is higher than the pressure in the surrounding wellbore and formation.
This intemal pressure differential actuates a bypass of the flow restrictor disposed within
each ICD in the production string. However, in another embodiment, this internal pressure
25 differential may only actuate a portion of the ICDs in the production string. After at least a
portion of the ICDs have been actuated, pressure within the intemal passageway of the
production string may be decreased, such as to create an external pressure differential
where the pressure within the formation and wellbore is higher than the pressure within the
intemal passageway, causing flow into the intemal passageway which may now bypass the
18-
10
ICD due to the actuation of the bypass mechanism. A fluid flow into the internal
passageway from the formation may have a lower pressure drop due to bypassing the flow
restrictor disposed within the ICD.
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
variations and modifications of the systems, apparatus, and processes 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. 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.
19-

WE CLAIM:
1. A bypass assembly for use in a downhole tool comprising:
a chamber;
a first fluid port in fluid communication with the chamber;
a second fluid port in fluid communication with the chamber;
a flow restrictor disposed in a first flow path between the first fluid port and the
second fluid port;
a piston moveable in a first direction by the application of a first fluid pressure;
a biasing member, wherein the biasing member biases the piston to move in a
second direction opposite the first direction; and
a restraining member disposed adjacent to the piston, wherein the restraining
member is actuated by movement of the piston in the first direction in
response to a predetermined fluid pressure;
wherein movement of the piston in the second direction to a predetermined position
configures the bypass assembly to divert fluid flow around the flow
restrictor along a second flow path.
2. A bypass assembly as claimed in claim 1, wherein the flow restrictor creates a first
pressure drop in fluid flowing through the flow restrictor between the first port and the
second port.
3. A bypass assembly as claimed in claim 2, wherein the flow restrictor and the piston
are in sealing engagement and are configured to create the first pressure drop.
4. A bypass assembly as claimed in claim 2, wherein the movement of the piston to
the predetermined position creates a second pressure drop in a fluid flow between the first
port and the second port, and where the second pressure drop is less than the first pressure
drop.
5. A bypass assembly as claimed in claim 2, wherein the first pressure drop is
maintained during the movement of the piston in the first direction.
6. A bypass assembly as claimed in claim 1, wherein the piston is moveable in the
second direction in response to a second, lower pressure applied from the second port.
7. A flow control device for use in a downhole tool comprising:
a flow restriction disposed in a first flow path between a first port and a second
port; and
a bypass mechanism configured to be moveable between a first position and a
second position in response to a first pressure,
wherein the first flow path between the first port and the second port is established
when the bypass mechanism is in the first position, and
wherein a second flow path between the first port and second port is established
when the bypass mechanism is in the second position.
8. A flow control device as claimed in claim 7, wherein the flow restriction comprises
a flow restrictor configured to create a helical flow path.
9. A flow control device as claimed in claim 7, wherein the flow restriction comprises
a nozzle.
10. A flow control device as claimed in claim 7, wherein the second flow path is
configured to provide a lower pressure drop than the first flow path.
11. A flow control device as claimed in claim 7, wherein the bypass mechanism
comprises:
a pipe having an interior passageway for conveying fluids;
a housing disposed about the pipe and forming a chamber between the housing and
the pipe, wherein the first port provides fluid communication between the
interior passageway and the chamber and the second portion provides fluid
communication between the chamber and an exterior of the housing; and
a piston disposed within the chamber and moveable between the first position and
the second position, wherein the piston divides the chamber into first and
second portions.
12. A flow control device as claimed in claim 11, wherein the bypass mechanism
further comprises:
a biasing member disposed in the second portion of the chamber; and
a restraining member disposed adjacent to the piston.
13. A flow control device as claimed in claim 11, wherein the piston is moveable to a
third position that is displaced from the first position and the second position, and wherein
the piston is sealed against the flow restriction while positioned in the third position.
14. A flow control device as claimed in claim 12, wherein the restraining member is a
shear member that is shearable at a predetermined pressure applied to a surface of the
piston that is within the first portion of the chamber.
15. A flow control device as claimed in claim 14, wherein the shear member and
biasing member are configured to apply a biasing force on the piston towards the second
position in response to shearing the shear member.
16. A flow control device as claimed in claim 12, further comprising a third port
providing a path for fluid to pass out of the second portion of the chamber when the piston
compresses the biasing member.
17. A flow control device as claimed in claim 12, wherein the restraining member
comprises a J-slot mechanism configured to release the piston for axial movement when a
predetermined pressure is applied to the first portion of the chamber.
18. A method for bypassing a flow restrictor comprising:
flowing a fluid through a first flow path between a first port and a second port.
wherein the first flow path comprises a flow restrictor;
translating a moveable element in response to a pressure applied to the moveable
element, wherein the translating the moveable element opens a second flow
path between the first port and the second port; and
flowing a fluid through the second flow path.
19. A method as claimed in claim 18, further comprising flowing a fluid through a third
flow path between the second port and the first port.
20. A method as claimed in claim 19, wherein the pressure is created by the fluid
flowing through the third flow path.