U.S. patent application number 17/403705 was filed with the patent office on 2022-02-17 for shutoff valve.
This patent application is currently assigned to PetroQuip Energy Services, LLC. The applicant listed for this patent is PetroQuip Energy Services, LLC. Invention is credited to Robert Coon, John Lee Emerson, Antonio B. Flores, Roddie Smith.
Application Number | 20220049575 17/403705 |
Document ID | / |
Family ID | |
Filed Date | 2022-02-17 |
United States Patent
Application |
20220049575 |
Kind Code |
A1 |
Coon; Robert ; et
al. |
February 17, 2022 |
Shutoff Valve
Abstract
A shutoff valve device for permitting and preventing fluid flow
in a production string. In one embodiments, the shutoff valve
device comprising: a body comprising a borehole, wherein the body
is a top sub coupled to a bottom sub via a threaded fastener; a
flow tube disposed within the body's borehole and capable of axial
movement within the body's borehole, comprising a flow tube
borehole; a bi-directional actuator attached to a bottom opening of
the flow tube, comprising flexible flaps; and a flapper valve
disposed within the body's borehole, wherein the flapper valve is
hingedly coupled to a top surface of the bottom sub and capable of
moving between a fully opened and fully closed position.
Inventors: |
Coon; Robert; (Missouri
City, TX) ; Smith; Roddie; (Katy, TX) ;
Emerson; John Lee; (Katy, TX) ; Flores; Antonio
B.; (Cypress, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PetroQuip Energy Services, LLC |
Waller |
TX |
US |
|
|
Assignee: |
PetroQuip Energy Services,
LLC
Waller
TX
|
Appl. No.: |
17/403705 |
Filed: |
August 16, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
63065864 |
Aug 14, 2020 |
|
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International
Class: |
E21B 34/12 20060101
E21B034/12 |
Claims
1. A shutoff valve device for permitting and preventing fluid flow
in a production string, comprising: a body comprising a borehole,
wherein the body is a top sub coupled to a bottom sub via a
threaded fastener; a flow tube disposed within the body's borehole
and capable of axial movement within the body's borehole,
comprising a flow tube borehole; a bi-directional actuator attached
to a bottom opening of the flow tube, comprising flexible flaps;
and a flapper valve disposed within the body's borehole, wherein
the flapper valve is hingedly coupled to a top surface of the
bottom sub and capable of moving between a fully opened and fully
closed position.
2. The shutoff valve device of claim 1, wherein the top sub is
further coupled to the bottom sub via shear screws to provide a
means in which to shear the top sub from the bottom sub.
3. The shutoff valve device of claim 1, wherein the bi-directional
actuator is made up of rubber material.
4. The shutoff valve device of claim 1, wherein the flapper valve
is positioned in a flapper valve recess when in the fully open
position.
5. The shutoff valve device of claim 1, wherein the flapper valve
is positioned to mate with a valve seat when in the fully closed
position.
6. The shutoff valve device of claim 1, wherein the borehole
comprises ledges to limit the axial movement of the flow tube.
7. The shutoff valve device of claim 1, further comprising a
pump-open sleeve disposed about an outer surface of the body, and
wherein the pump-open sleeve covers openings in the body.
8. The shutoff valve device of claim 7, wherein the pump-open
sleeve is attached to the body via secondary shear screws to
provide a means to actuate pump-open sleeve, thereby uncovering the
openings.
9. A shutoff valve device for permitting and preventing fluid flow
in a production string, comprising: a body comprising a borehole,
wherein the body is a top sub coupled to a bottom sub via a
threaded fastener; a flow tube disposed within the body's borehole
and capable of axial movement within the body's borehole,
comprising a flow tube borehole; a compression spring disposed
radially between the flow tube and the body, wherein the
compression spring biases the flow tube in an axially upward
position; a bi-directional actuator attached to a bottom opening of
the flow tube, comprising flexible flaps; and a flapper valve
disposed within the body's borehole, wherein the flapper valve is
hingedly coupled to a top surface of the bottom sub and capable of
moving between a fully opened and fully closed position.
10. The shutoff valve device of claim 9, wherein the top sub is
further coupled to the bottom sub via shear screws to provide a
means in which to shear the top sub from the bottom sub.
11. The shutoff valve device of claim 9, wherein the bi-directional
actuator is made up of rubber material.
12. The shutoff valve device of claim 9, wherein the flapper valve
is positioned in a flapper valve recess when in the fully open
position.
13. The shutoff valve device of claim 9, wherein the flapper valve
is positioned to mate with a valve seat when in the fully closed
position.
14. The shutoff valve device of claim 9, wherein the borehole
comprises ledges to limit the axial movement of the flow tube.
15. The shutoff valve device of claim 9, further comprising a
pump-open sleeve disposed about an outer surface of the body, and
wherein the pump-open sleeve covers openings in the body.
16. The shutoff valve device of claim 15, wherein the pump-open
sleeve is attached to the body via secondary shear screws to
provide a means to actuate pump-open sleeve, thereby uncovering the
openings.
17. A method for permitting and preventing fluid flow in a
production string, comprising: (A) outfitting a production string
with a shutoff valve device comprising: a body comprising a
borehole, wherein the body is a top sub coupled to a bottom sub via
a threaded fastener; a flow tube disposed within the body's
borehole and capable of axial movement within the body's borehole,
comprising a flow tube borehole; a bi-directional actuator attached
to a bottom opening of the flow tube, comprising flexible flaps;
and a flapper valve disposed within the body's borehole, wherein
the flapper valve is hingedly coupled to a top surface of the
bottom sub and capable of moving between a fully opened and fully
closed position.
18. The method of claim 17, wherein upward fluid flow through the
borehole opens the shutoff valve device by providing an upward
force that engages the bi-directional actuator, thereby moving the
flow tube axially upward, which in turn opens the flapper valve and
permits fluid flow.
19. The method of claim 17, wherein downward fluid flow through the
borehole closes the shutoff valve device by providing a downward
force that engages the bi-directional actuator, thereby moving the
flow tube axially downward, which in turn allows the flapper valve
the ability to be closed by the downward force and prevent fluid
flow.
20. The method of claim 17, wherein the bi-directional actuator is
made up of rubber material.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a non-provisional application that
claims the benefit of U.S. Application Ser. No. 63/065,864 filed
Aug. 14, 2020, the disclosure of which are incorporated by
reference herein in their entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OF DEVELOPMENT
[0002] Not applicable.
BACKGROUND
1. Field of Inventions
[0003] The field of this application and any resulting patent is an
improved valve, and in particular, but not exclusively, to
improvements in and relating to a downhole shutoff valve.
2. Description of Related Art
[0004] Various systems and methods have been proposed and utilized
for preventing fluids from flowing back into a formation once
production is stopped, including some of the systems and methods in
the references appearing on the face of this patent. However, those
systems and methods lack all the steps or features of the systems
and methods covered by any patent claims below. As will be apparent
to a person of ordinary skill in the art, any systems and methods
covered by claims of the issued patent solve many of the problems
that prior art systems and methods have failed to solve. Also, the
systems and methods covered by at least some of the claims of this
patent have benefits that could be surprising and unexpected to a
person of ordinary skill in the art based on the prior art existing
at the time of invention.
SUMMARY
[0005] One or more specific embodiments disclosed herein includes a
shutoff valve device that may comprise a top sub, a bottom sub, and
a flow tube, wherein the bottom sub may comprise a flapper valve
and a valve seat, and further wherein the flow tube may comprise
drag features designed to move the flow tube back and forth from a
first position (holding the flapper valve in a completely open
position) to a second position (allowing the flapper valve to a
closed, sealed position), depending on the direction of fluid flow
in the wellbore.
[0006] One or more specific embodiments disclosed herein includes a
shutoff valve device for permitting and preventing fluid flow in a
production string, comprising: a body comprising a borehole,
wherein the body is a top sub coupled to a bottom sub via a
threaded fastener; a flow tube disposed within the body's borehole
and capable of axial movement within the body's borehole,
comprising a flow tube borehole; a bi-directional actuator attached
to a bottom opening of the flow tube, comprising flexible flaps;
and a flapper valve disposed within the body's borehole, wherein
the flapper valve is hingedly coupled to a top surface of the
bottom sub and capable of moving between a fully opened and fully
closed position.
[0007] One or more specific embodiments disclosed herein includes a
shutoff valve device for permitting and preventing fluid flow in a
production string, comprising: a body comprising a borehole,
wherein the body is a top sub coupled to a bottom sub via a
threaded fastener; a flow tube disposed within the body's borehole
and capable of axial movement within the body's borehole,
comprising a flow tube borehole; a compression spring disposed
radially between the flow tube and the body, wherein the
compression spring biases the flow tube in an axially upward
position; a bi-directional actuator attached to a bottom opening of
the flow tube, comprising flexible flaps; and a flapper valve
disposed within the body's borehole, wherein the flapper valve is
hingedly coupled to a top surface of the bottom sub and capable of
moving between a fully opened and fully closed position.
[0008] One or more specific embodiments disclosed herein includes a
method for permitting and preventing fluid flow in a production
string, comprising: outfitting a production string with a shutoff
valve device comprising: a body comprising a borehole, wherein the
body is a top sub coupled to a bottom sub via a threaded fastener;
a flow tube disposed within the body's borehole and capable of
axial movement within the body's borehole, comprising a flow tube
borehole; a bi-directional actuator attached to a bottom opening of
the flow tube, comprising flexible flaps; and a flapper valve
disposed within the body's borehole, wherein the flapper valve is
hingedly coupled to a top surface of the bottom sub and capable of
moving between a fully opened and fully closed position.
[0009] The foregoing has outlined rather broadly the features and
technical advantages of the present invention in order that the
detailed description of the invention that follows may be better
understood. Additional features and advantages of the invention
will be described hereinafter that form the subject of the claims
of the invention. It should be appreciated by those skilled in the
art that the conception and the specific embodiments disclosed may
be readily utilized as a basis for modifying or designing other
embodiments for carrying out the same purposes of the present
invention. It should also be realized by those skilled in the art
that such equivalent embodiments do not depart from the spirit and
scope of the invention as set forth in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] For a detailed description of the preferred embodiments of
the invention, reference will now be made to the accompanying
drawings in which:
[0011] FIG. 1A-1C each illustrate a portion of a production string
configured with a shutoff valve in accordance with embodiments of
the present invention;
[0012] FIG. 2 illustrates an internal side view of a shutoff valve
in accordance with embodiments of the present invention;
[0013] FIG. 3 illustrates a perspective view of a portion of a
bottom sub of a shutoff valve in accordance with embodiments of the
present invention;
[0014] FIGS. 4A-4D each illustrate an orifice disk in accordance
with embodiments of the present invention;
[0015] FIGS. 5A and 5B each illustrate an internal side view of an
alternative flapper valve in accordance with embodiments of the
present invention;
[0016] FIG. 6A-6C each illustrate an internal side view of a
shutoff valve in accordance with embodiments of the present
invention in different operating positions;
[0017] FIG. 7A-7C each illustrate an internal side view of an
alternative shutoff valve in accordance with embodiments of the
present invention in different operating positions;
[0018] FIGS. 8A and 8B each illustrate an internal side view of an
alternative shutoff valve in accordance with embodiments of the
present invention in different operating positions;
[0019] FIGS. 9A and 9B each illustrate an internal side view of an
alternative shutoff valve in accordance with embodiments of the
present invention in different operating positions;
[0020] FIGS. 10A-10G illustrate a progression of debris removal
from a shutoff valve 100 in accordance with embodiments of the
present invention.
DETAILED DESCRIPTION
1. Introduction
[0021] A detailed description will now be provided. The purpose of
this detailed description, which includes the drawings, is to
satisfy the statutory requirements of 35 U.S.C. .sctn. 112. For
example, the detailed description includes a description of the
inventions defined by the claims and sufficient information that
would enable a person having ordinary skill in the art to make and
use the inventions. In the figures, like elements are generally
indicated by like reference numerals regardless of the view or
figure in which the elements appear. The figures are intended to
assist the description and to provide a visual representation of
certain aspects of the subject matter described herein. The figures
are not all necessarily drawn to scale, nor do they show all the
structural details of the systems, nor do they limit the scope of
the claims.
[0022] Each of the appended claims defines a separate invention
which, for infringement purposes, is recognized as including
equivalents of the various elements or limitations specified in the
claims. Depending on the context, all references below to the
"invention" may in some cases refer to certain specific embodiments
only. In other cases, it will be recognized that references to the
"invention" will refer to the subject matter recited in one or
more, but not necessarily all, of the claims. Each of the
inventions will now be described in greater detail below, including
specific embodiments, versions, and examples, but the inventions
are not limited to these specific embodiments, versions, or
examples, which are included to enable a person having ordinary
skill in the art to make and use the inventions when the
information in this patent is combined with available information
and technology.
2. Specific Embodiments in the Figures
[0023] The drawings presented herein are for illustrative purposes
only and are not intended to limit the scope of the claims. Rather,
the drawings are intended to help enable one having ordinary skill
in the art to make and use the claimed inventions.
[0024] Referring to FIGS. 1A-10G, specific embodiments, e.g.,
versions or examples, of a shutoff valve are illustrated. These
figures may show features which may be found in various specific
embodiments, including the embodiments shown in this specification
and those not shown.
[0025] FIGS. 1A-1C each illustrate a portion of a production string
2, a primary conduit through which reservoir fluids are produced to
surface. Depending on wellbore conditions and desired production
method, production string 2 may be configured and/or assembled with
various tubing and completion components. As illustrated in FIG.
1A, production string 2 may be configured for gas lift application
and comprise, without limitation, tubing 4, an artificial lift
completion such as a gas lift mandrel 6, an on-off tool 8, a
retrievable production packer 10, or any combinations thereof.
Alternatively, as illustrated in FIG. 1B, production string 2 may
be configured for electric submersible pump (ESP) application and
comprise, without limitation, tubing 4, an artificial lift
completion such as an ESP 12, retrievable production packer 10, or
any combinations thereof. In addition to the various completion
components, production string 2 may comprise a shutoff valve 100, a
flow actuated device that creates a down hole barrier to prevent
loss of kill fluid into a reservoir or formation when downhole flow
may be reversed, for instance when production may be stopped. Loss
of said kill fluid could damage the reservoir and/or formation. In
embodiments, shutoff valve 100 may be installed at any suitable
location on production string 2. As illustrated in both FIGS. 1A
and 1B, shutoff valve 100 may be installed below (further downhole)
gas lift mandrel 6 or ESP 12 as well as below retrievable
production packer 10. Alternatively, although not illustrated,
shutoff valve 100 may be installed above (further uphole) gas lift
mandrel 6 or ESP 12 as well as above retrievable production packer
10. Further alternatively, shutoff valve 100 may be installed below
gas lift mandrel 6 or ESP 12 and above retrievable production
packer 10, as illustrated in FIG. 1C. In such an embodiment,
shutoff valve 100 may comprise a fish neck 3 and flow ports 5.
[0026] In embodiments, shutoff valve 100 may be installed on new or
existing completion strings of various tubing sizes, which in turn
may govern the size of shutoff valve 100. Standard tubing size
(measured from an outer diameter) may range from about 23/8 inches
to about 41/2 inches. In embodiments, the tubing size may be 27/8
inches, 31/2 inches, or 41/2 inches. Depending on the tubing size,
shutoff valve 100 may be manufactured in a range of suitable sizes,
comprising an outer diameter between about 4 inches and about 8
inches and an inner diameter between about 2 inches and about 4
inches. Note that the outer diameter may be measure from the point
of greatest outer diameter of shutoff valve 100 and the inner
diameter may be measured from the point of smallest inner diameter
of shutoff valve 100, particularly in embodiments in which the
outer and inner diameters of shutoff valve 100 may be variable
along the axial length. In embodiments, shutoff valve 100, when
employed on a completion string using tubing sized to 2% inches,
may comprise an outer diameter measuring about 4.65 inches and an
inner diameter measuring about 2.31 inches. Alternatively, shutoff
valve 100, when employed on a completion string using tubing sized
to 31/2 inches, may comprise an outer diameter measuring about 5.20
inches and an inner diameter measuring about 2.75 inches. Further
alternatively, shutoff valve 100, when employed on a completion
string with tubing sized to 41/2 inches, may comprise an outer
diameter measuring about 7.20 inches and an inner diameter
measuring about 3.75 inches. Depending on tubing size, shutoff
valve 100 may be rated for high pressures between about 5,000 psi
to about 15,000 psi. In embodiments, shutoff valve 100 may be rated
for pressures up to 10,000 psi. Further, shutoff valve 100 may be
rated for standard and high temperatures between about 300.degree.
F. and about 700.degree. F. In embodiments, shutoff valve may be
rated for a standard temperature of about 350.degree. F., or
alternatively for a high temperature of about 600.degree. F.
Regardless of the tubing size, shutoff valve 100 may be
manufactured to any suitable axial length, ranging from about 25
inches to about 45 inches. In embodiments, the overall axial length
of shutoff valve 100 may be about 35 inches.
[0027] FIG. 2 illustrates an internal side view of an embodiment of
shutoff valve 100. Shutoff valve 100 may comprise a top sub 102, a
bottom sub 104, a flow tube 106, and a flapper valve 126. In
embodiments, top sub 102 and bottom sub 104 may be hollow-bodied
metal components coupled together via any suitable fastening
mechanisms, thereby forming a borehole 118 through which fluid may
flow. Top sub 102 and/or bottom sub 104 may be manufactured from
any oil field steel. For example, top sub 102 and/or bottom sub 104
may be manufactured from L-80 Steel, P-110 Steel, 9 Chrome, 13
Chrome, etc. In embodiments, suitable fastening mechanisms may
comprise, without limitation, a threaded fastener 122, shear screws
124, or any combinations thereof. Threaded fastener 122 may
comprise female/internal threading disposed on a portion of the
interior surface of top sub 102 as well as corresponding
male/external threading disposed on a portion of the exterior
surface of bottom sub 104, thus providing a means by which bottom
sub 104 may be screwed into top sub 102. The male/external
threading of threaded fastener 122 as well as some other components
may be further depicted in FIG. 3, illustrating a perspective view
of a portion of bottom sub 104. In some embodiments, threaded
fastener 122 may comprise a 4- 5/16-inch diameter, 8 thread per
inch, ACME thread with a class 2G. In other embodiments, other
thread types may be employed. Referring once again to FIG. 2, a top
portion of bottom sub 104 may be screwed into a bottom portion of
top sub 102 via threaded fastener 122 until the bottom portion of
top sub 102 engages a flange 116 of bottom sub 104. In conjunction
with or independent of threaded fastener 122, shear screws 124 may
be employed to connect top sub 102 to bottom sub 104. In
embodiments, shear screws 124 may be threaded through top sub 102
and bottom sub 104 in a radial direction at a point at which the
bottom portion of top sub 102 overlaps with the top portion of
bottom sub 104. Shear screws 124 may allow for shearing between top
sub 102 and bottom sub 104 in the event of emergency or malfunction
of shutoff valve 100, such as an inadvertent obstruction of fluid
flow through borehole 118. Shearing may be performed by applying a
pressure to shutoff valve 100 that exceeds its overall pressure
rating. In some embodiments, shutoff valve 100 may further comprise
a sealing element 132 disposed radially between top sub 102 and
bottom sub 104 at the point at which the bottom portion of top sub
102 overlaps with the top portion of bottom sub 104. Sealing
element 132 may be any suitable sealing mechanism such as, without
limitation, an O-ring or the like, which may be capable of
preventing fluid leakage from borehole 118. In embodiments,
borehole 118 may comprise upper and lower portions 119 and 121,
each having a diameter corresponding to that of the tubing utilized
in the completion string on which shutoff valve 100 may be
installed (i.e., the inner diameter of shutoff valve 100). Further,
borehole 118 may comprise a middle portion 123 having a variable
diameter greater than that of upper and lower portions 119 and
121.
[0028] As illustrated in FIG. 2, middle portion 123 may contain
flow tube 106, a hollow-bodied metal cylinder comprising a flow
tube borehole through which fluid flowing through borehole 118 may
pass. In embodiments, flow tube 106 may be sized to fit within
middle portion 123, such that the flow tube borehole may be in-line
with upper and lower portions 119 and 121, as well as correspond in
diameter to that of upper and lower portions 119 and 121. Further,
flow tube 106 may be sized, particularly in length, to be capable
of axial movement within middle portion 123. To aid in facilitating
this axial movement, embodiments of flow tube 106 may be outfitted
with an orifice disk 146 by any suitable means. Orifice disk 146
may be a bi-directional actuator of a single, circular component
attached over a bottom opening of flow tube 106 via screws 148,
thus providing a partial covering of the bottom opening. In
embodiments, orifice disk 146 may be mad up of proprietary
fiber-infused, erosion-resistant material such as, without
limitation, rubber materials.
[0029] FIGS. 4A-4D illustrate different embodiments of orifice disk
146 with one or more holes 149 to receive screws 148. In
embodiments, orifice disk 146, on addition to holes 149, may
comprise an opening 147 and any suitable number of flexible flaps
152. FIG. 4A illustrates an embodiment of orifice disk 146
comprising opening 147 and six flexible flaps 152, FIG. 4B
illustrates an embodiment of orifice disk 146 comprising opening
147 and three flexible flaps 152, and FIG. 4C illustrates an
embodiment of orifice disk 146 comprising opening 147 and four
flexible flaps 152. FIG. 4D, as opposed to FIGS. 4A-4C, may not
initially comprise opening 147, but rather may only initially
comprise three flexible flaps 152, in addition to holes 149. For
such an embodiment, it may not be until orifice disk 146
experiences fluid flow that opening 147 may be revealed through
spacing in flexible flaps 152 caused by the fluid flow. Orifice
disk 146, having flexibility by nature of material, may allow for
fluid to flow through opening 147 and flexible flaps 152 at the
bottom opening of flow tube 106 and manipulate the axial movement
of flow tube 106. Further, orifice disk 146, having durability by
nature of material, may experience minimal erosion that could
otherwise be caused by the flowing fluid.
[0030] Referring to FIG. 2, middle portion 123 may further contain
flapper valve 126, a circular metal flapper capable of obstructing
fluid flow within borehole 118. In embodiments, flapper valve 126
may be sized, particularly in area, to be seated on a valve seat
136 comprising a sealing element 134, and further may be disposed
on a top surface of bottom sub 104. As such, flapper valve 126 may
be capable of fully covering a top opening of flow tube 106.
Further, flapper valve 126 may be connected to the top surface of
bottom sub 104 via a hinge pin connection 141 comprising a hinge
pin 140 and a spring 138 (e.g., a torsion spring, a compression
spring, a tension spring, or the like) to allow for hinged movement
of flapper valve 126 within middle portion 123. In embodiments,
flapper valve 126 may be capable of moving between a fully opened
position and a fully closed position. The fully opened position may
comprise flapper valve 126 being positioned at about a 90.degree.
angle relative to the top surface of bottom sub 104 within a
flapper valve recess 125 of middle portion 123, while the fully
closed position may comprise flapper valve 126 being positioned at
about a 0.degree. angle relative to the top surface of bottom sub
104, in complete contact with valve seat 136. Alternate embodiments
of flapper valve 126 and valve seat 136 may be illustrated in FIGS.
5A and 5B. FIG. 5A illustrates an angled flapper valve 126
comprising an angled edge 127 to correspondingly mate with angled
valve seat 136. FIG. 5B illustrates a flapper valve 126 capable of
mating with a ridged valve seat 136 comprising a ridge 137.
Although not exhaustively illustrated, flapper valve 126 may be any
shape suitable for properly mating with valve seat 136 such as,
without limitation, straight, convex, and/or concaved, as it
relates to fluid flow in the downhole direction.
[0031] In embodiments, flow tube 106 and flapper valve 126 may
operate in conjunction to permit or prevent flow through borehole
118 of shutoff valve 100. FIGS. 6A-6C illustrate various positions
in which shutoff valve 100 may operate. FIG. 6A, which is the same
as FIG. 2 described above, illustrates shutoff valve 100 in an
initial resting position during operation. In this position, flow
tube 106, through the assistance of gravity, may be disposed below
flapper valve 126 such that the bottom of flow tube 106 may be
resting on a lower ledge 130. Lower ledge 130 may provide a means
in which to prevent any further downward axial movement of flow
tube 106 during operation. Further, flapper valve 126, through the
assistance of spring 138, may be biased in a partially opened
position at about a 45.degree. angle relative to the top surface of
bottom sub 104. In this position, there may be minimal or no fluid
flowing through borehole 118.
[0032] FIG. 6B illustrates shutoff valve 100 in a fully opened
position during operation. In this position, flow tube 106 may be
disposed such that the top opening may be in contact with an upper
ledge 120 and an outer portion of orifice disk 146 disposed at the
bottom opening of flow tube 106 may be in contact with a middle
ledge 131. In embodiments, the contact between the outer portion of
orifice disk 146 and middle ledge 131 may aid in preventing fluid
from leaking into an annulus between flow tube 106 and top and
bottom subs 102 and 104. Upper ledge 120 and middle ledge 131 may
provide a means in which to prevent any further upward axial
movement of flow tube 106 during operation. Further, flapper valve
126 may be in the fully opened position. This positioning of flow
tube 106 and flapper valve 126 may be caused by fluid flowing
upward through borehole 118, toward the surface of the well. The
upward flowing fluid may engage with flexible flaps 152 of orifice
disk 146, pushing flexible flaps 152 toward the surface of the
well, thereby forcing flow tube 106 to move axially upward until
reaching upper ledge 120 and middle ledge 131. In this position,
fluid may continuously flow through borehole 118, passing through
opening 147 of orifice disk 146, which includes any space created
by the displacement of flexible flaps 152, as well as through the
flow tube borehole. This may occur with a minimal pressure drop of
less than 3 psi. Further in this position, flapper valve 126 may be
isolated from the upward flowing fluid, thus preventing any erosion
to flapper valve 126 that may otherwise be caused by the upward
flowing fluid.
[0033] FIG. 6C illustrates shutoff valve 100 in a fully closed
position. In this position, similarly to the initial resting
position, flow tube 106 may be disposed below flapper valve 126
such that the bottom of flow tube 106 may be resting on lower ledge
130. However, flapper valve 126 may be in the fully closed
position, thus preventing any fluid flow within borehole 118. This
positioning of flow tube 106 and flapper valve 126 may be caused by
fluid flowing downward through borehole 118, in a downhole
direction. The downward flowing fluid may engage with flexible
flaps 152 of orifice disk 146, pushing flexible flaps 152 downward,
thereby forcing flow tube 106 to move axially downward until
reaching lower ledge 130. Further, the downward flowing fluid may
engage with a top side of flapper valve 126, pushing flapper valve
126 into valve seat 136. In embodiments, sealing element 134 may
provide an initial seal for flapper valve 126 until load from the
pressure differential of the downward flowing fluid creates a
metal-to-metal seal between flapper valve 126 and valve seat 136.
In this position, fluid flow within borehole 118 may be halted,
thus preventing any kill fluid from flowing back into the
formation, particularly when production has stopped. This may
reduce potential reservoir damage due to fluid loss.
[0034] FIGS. 7A-7C illustrate an alternative embodiment of shutoff
valve 100. In this embodiment, shutoff valve 100 may comprise an
alternative flow tube 111, which may be similar to that of flow
tube 106, but comprises a drag section 154 rather than orifice disk
146. Drag section 154 may be a section of flow tube 111 of smaller
inner diameter or smaller inner and outer diameter comprising one
or more surface-facing drags 156 and one or more downhole-facing
drags 158. In such embodiments, drag section 154 may provide
similar functionality for shutoff valve 100 as that of orifice disk
146. FIG. 7A, illustrates shutoff valve 100 in an initial resting
position during operation. In this position, flow tube 111, through
the assistance of gravity, may be disposed below flapper valve 126
such that the bottom of flow tube 111 may be resting on lower ledge
130. Lower ledge 130 may provide a means in which to prevent any
further downward axial movement of flow tube 111 during operation.
Further, flapper valve 126, through the assistance of spring 138,
may be biased in a partially opened position at about a 45.degree.
angle relative to the top surface of bottom sub 104. In this
position, there may be minimal or no fluid flowing through borehole
118.
[0035] FIG. 7B illustrates shutoff valve 100 in a fully opened
position during operation. In this position, flow tube 111 may be
disposed such that the top opening may be in contact with upper
ledge 120. Upper ledge 120 may provide a means in which to prevent
any further upward axial movement of flow tube 111 during
operation. Further, flapper valve 126 may be in the fully opened
position. This positioning of flow tube 111 and flapper valve 126
may be caused by fluid flowing upward through borehole 118, toward
the surface of the well. The upward flowing fluid may engage with
downhole-facing drag 158, thereby forcing flow tube 111 to move
axially upward until reaching upper ledge 120. In this position,
fluid may continuously flow through borehole 118, passing through
the flow tube borehole. This may occur with a minimal pressure drop
of less than 3 psi. Further in this position, flapper valve 126 may
be isolated from the upward flowing fluid, thus preventing any
erosion to flapper valve 126 that may otherwise be caused by the
upward flowing fluid.
[0036] FIG. 7C illustrates shutoff valve 100 in a fully closed
position. In this position, similarly to the initial resting
position, flow tube 111 may be disposed below flapper valve 126
such that the bottom of flow tube 111 may be resting on lower ledge
130. However, flapper valve 126 may be in the fully closed
position, thus preventing any fluid flow within borehole 118. This
positioning of flow tube 111 and flapper valve 126 may be caused by
fluid flowing downward through borehole 118, in a downhole
direction. The downward flowing fluid may engage with
surface-facing drag 156, thereby forcing flow tube 111 to move
axially downward until reaching lower ledge 130. Further, the
downward flowing fluid may engage with a top side of flapper valve
126, pushing flapper valve 126 into valve seat 136. In embodiments,
sealing element 134 may provide an initial seal for flapper valve
126 until load from the pressure differential of the downward
flowing fluid creates a metal-to-metal seal between flapper valve
126 and valve seat 136. In this position, fluid flow within
borehole 118 may be halted, thus preventing any kill fluid from
flowing back into the formation, particularly when production has
stopped. This may reduce potential reservoir damage due to fluid
loss.
[0037] FIGS. 8A and 8B illustrate an alternative embodiment of
shutoff valve 100. In this embodiment, shutoff valve 100 may
comprise an alternative flow tube 107, which may be similar to that
of flow tube 106, but further comprise flow tube notch 166. Further
in this embodiment, shutoff valve 100 may comprise a flow tube
spring 160, a compression spring disposed radially between flow
tube 107 and bottom sub 104 and axially between movable spring
guard 162 and stationary spring guard 164. In some embodiments,
bottom sub 104 may consist of two parts 103 and 105 coupled
together by any suitable fastening mechanisms as previously
described. In such embodiments, flow tube spring 160 may be
radially disposed between flow tube 107 and bottom sub part 103.
FIG. 8A illustrates alternative shutoff valve 100 in an initial
resting position/fully opened position during operation. In this
position, spring 160 may bias flow tube 107 such that the top
opening may be in contact with upper ledge 120, an outer portion of
orifice disk 146 may be in contact with middle ledge 131, and a
connection point 143 between orifice disk 146 and flow tube 107 may
be in contact with stationary spring guard 164. In embodiments, the
contact between the outer portion of orifice disk 146 and middle
ledge 131 may aid in preventing fluid from leaking into an annulus
between flow tube 107 and top and bottom subs 102 and 104. Upper
ledge 120 and middle ledge 131 may provide a means in which to
prevent any further upward axial movement of flow tube 107 during
operation. Further, flapper valve 126 may be in the fully opened
position. This positioning of flow tube 107 and flapper valve 126
may be caused or assisted by decompression of flow tube spring 160,
which may be capable of applying an upward force through movable
spring guard 132 to flow tube notch 166, particularly when there
may be minimal or no fluid flowing through borehole 118, or rather
when fluid may be flowing upward through borehole 118, toward the
surface of the well. Similar to previous embodiments, in this
position, fluid may continuously flow through borehole 118, passing
through opening 147 of orifice disk 146, which includes any space
created by the displacement of flexible flaps 152, as well as
through the flow tube borehole. This may occur with a minimal
pressure drop of less than 3 psi. Further in this position, flapper
valve 126 may be isolated from the upward flowing fluid, thus
preventing any erosion to flapper valve 126 that may otherwise be
caused by the upward flowing fluid.
[0038] FIG. 8B illustrates alternative shutoff valve 100 in a fully
closed position during operation. In this position, downward
flowing fluid may bias flow tube 107 below flapper valve 126 such
that the bottom of flow tube 107 may be resting on lower ledge 130.
Further, flapper valve 126 may be in the fully closed position.
This positioning of flow tube 107 and flapper valve 126 may be
caused or assisted by fluid flowing downward through borehole 118,
in a downhole direction. The downward flowing fluid may engage with
flexible flaps 152 of orifice disk 146, pushing flexible flaps 152
downward, thereby forcing flow tube 107 to move axially downward
until reaching lower ledge 130. As such, flow tube notch 166 may
apply a downward force to movable spring guard 162 thereby axially
displacing movable spring guard 162 in the downward direction and
compressing spring 160 between movable spring guard 162 and
stationary spring guard 164. Further, the downward flowing fluid
may engage with a top side of flapper valve 126, pushing flapper
valve 126 into valve seat 136. Similar to previous embodiments,
sealing element 134 may provide an initial seal for flapper valve
126 until load from the pressure differential of the downward
flowing fluid creates a metal-to-metal seal between flapper valve
126 and valve seat 136. In this position, fluid flow within
borehole 118 may be halted, thus preventing any kill fluid from
flowing back into the formation, particularly when production has
stopped. This may reduce potential reservoir damage due to fluid
loss.
[0039] FIGS. 9A and 9B illustrate an alternative embodiment of
shutoff valve 100. In this embodiment, shutoff valve 100 may
comprise an alternative flow tube 109, which may be similar to that
of flow tube 107, but further comprise an orifice disk extension
piece 145. In such embodiments, orifice disk 146 may be attached to
a bottom opening of orifice disk extension piece 145 via screws
148, while orifice disk extension piece 145 may in turn be attached
to flow tube 109 by any suitable means, such as screws 129. In
embodiments, flow tube 109 may function similarly to that of flow
tube 107, as is illustrated in FIGS. 9A and 9B. FIG. 9A illustrates
alternative shutoff valve 100 in an initial resting position/fully
opened position during operation. In this position, spring 160 may
bias flow tube 109 such that the top opening may be in contact with
upper ledge 120 and a connection point 171 between orifice disk
extension piece 145 and flow tube 109 may be in contact with
stationary spring guard 164. Upper ledge 120 and stationary spring
guard 164 may provide a means in which to prevent any further
upward axial movement of flow tube 109 during operation. Further,
flapper valve 126 may be in the fully opened position. Similar to
previous embodiments, this positioning of flow tube 109 and flapper
valve 126 may be caused or assisted by decompression of flow tube
spring 160, which may be capable of applying an upward force
through movable spring guard 132 to flow tube notch 166,
particularly when there may be minimal or no fluid flowing through
borehole 118, or rather when fluid may be flowing upward through
borehole 118, toward the surface of the well. In this position,
fluid may continuously flow through borehole 118, passing through
opening 147 of orifice disk 146, which includes any space created
by the displacement of flexible flaps 152, as well as through the
flow tube borehole. This may occur with a minimal pressure drop of
less than 3 psi. Further in this position, flapper valve 126 may be
isolated from the upward flowing fluid, thus preventing any erosion
to flapper valve 126 that may otherwise be caused by the upward
flowing fluid.
[0040] FIG. 9B illustrates alternative shutoff valve 100 in a fully
closed position during operation. In this position, downward
flowing fluid may bias flow tube 109 below flapper valve 126.
Further, flapper valve 126 may be in the fully closed position.
Similar to previous embodiments, this positioning of flow tube 109
and flapper valve 126 may be caused or assisted by fluid flowing
downward through borehole 118, in a downhole direction. The
downward flowing fluid may engage with flexible flaps 152 of
orifice disk 146, pushing flexible flaps 152 downward, thereby
forcing flow tube 109 to move axially downward until below closed
flapper valve 126. As such, flow tube notch 166 may apply a
downward force to movable spring guard 162 thereby axially
displacing movable spring guard 162 in the downward direction and
compressing spring 160 between movable spring guard 162 and
stationary spring guard 164. Further, the downward flowing fluid
may engage with a top side of flapper valve 126, pushing flapper
valve 126 into valve seat 136. Sealing element 134 may provide an
initial seal for flapper valve 126 until load from the pressure
differential of the downward flowing fluid creates a metal-to-metal
seal between flapper valve 126 and valve seat 136. In this
position, fluid flow within borehole 118 may be halted, thus
preventing any kill fluid from flowing back into the formation,
particularly when production has stopped. This may reduce potential
reservoir damage due to fluid loss. Although only depicted in FIGS.
9A and 9B thus far, orifice disk extension piece 145 may be
implemented on any one of the previous flow tube embodiments.
[0041] In addition to alternative flow tube 109, the alternative
embodiment of shutoff valve 100 illustrated in FIGS. 9A and 9B may
further comprise a pump-open sleeve 170. Pump-open sleeve 170 may
be a sleeve disposed about an outer surface of top sub 102 covering
openings 172, which may lead from borehole 118 to outside shutoff
valve 100. In embodiments, pump-open sleeve 170 may be attached to
top sub 102 via shear screws 176. Further, sealing elements 174 may
be disposed radially between top sub 102 and pump-open sleeve 170
to aid in sealing off openings 172. These openings 172 may be
disposed through top sub 102 in any suitable size, shape, and
number, and may provide a means by which to clean out any built-up
debris from above a fully closed flapper valve 126. Debris buildup
may prevent shutoff valve 100 from moving to the fully open
position after having been previously closed, thus may
inadvertently restrict fluid flow within borehole 118.
[0042] FIGS. 10A-10G illustrate a progression of debris removal
from an embodiment of shutoff valve 100 comprising pump-open sleeve
170 and experiencing a buildup of debris 180. FIG. 10A illustrates
an initial state of shutoff valve 100 experiencing a buildup of
debris 180 in a fully closed position. In order to remove debris
180, referring now to FIGS. 10B-10D an operator may apply a
differential pressure (depicted by arrows 182) to shutoff valve 100
in the downhole direction. This applied differential pressure may
be capable actuating pump-open sleeve 170 by shearing shear screws
176, thereby permanently uncovering openings 172. By actuating
pump-open sleeve 170, at least a portion of debris 180 may be
displaced from inside borehole 118 through openings 172. This
displacement of debris 180, referring now to FIGS. 10E-10G, may
allow at least some fluid flow (depicted by arrows 184) to be
restored through openings 172. In embodiments, as the at least some
fluid flow continues, the removal of debris 180 from above flapper
valve 126 may also continue. Eventually, enough debris 180 may be
removed so as to allow shutoff valve 100 to move to the fully open
position and thereby allow, once again, upward fluid flow through
borehole 118, as well as through openings 172. However, once
pump-open sleeve 170 has been actuated, shutoff valve 100 may no
longer be capable of moving to the fully closed position. In order
to recover this functionality, an operator may need to retrieve
shutoff valve 100 and redress the tool. Although only depicted in
FIGS. 8A-9G, pump-open sleeve 170 may be implemented on any one of
the previous shutoff valve embodiments.
[0043] The benefit of the embodiments of shutoff valve 100 may be
that it deals with some common problems in wellbore production. In
the absence of a shutoff valve in a producing well, the
unobstructed downward flow of fluid may allow the pumping mechanism
(e.g., an ESP or gas lift) to move in reverse, which could lead to
damage of the pump. This may be especially true if an operator
attempts to restart the pump while the pumping mechanism may
already be moving in reverse. Another problem may be that
unobstructed downward flow of fluid would be permitted to
uncontrollably move back into the formation, which could cause
serious issues with the productivity of the well. Alternatively, in
the absence of a shutoff valve, unwanted upward fluid flow may be
allowed to flow freely toward the surface of a well. To avoid this,
particularly in injection wells, the embodiments of shutoff valve
100 may be reciprocally installed, thus capable of preventing
unwanted upward fluid flow. Regardless of orientation, the
advantages of the embodiments of shutoff valve 100 may be that it
self-operates without the need for control lines or external
actuation signals, as well as reduces rig time by maintaining
static fluid level created by the downhole barrier.
[0044] Although the present invention and its advantages have been
described in detail, it should be understood that various changes,
substitutions and alterations may be made herein without departing
from the spirit and scope of the invention as defined by the
appended claims.
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