U.S. patent application number 13/155007 was filed with the patent office on 2012-12-13 for water hammer mitigating flow control structure and method.
This patent application is currently assigned to BAKER HUGHES INCORPORATED. Invention is credited to Terry R. Bussear, Keith J. Murphy.
Application Number | 20120312546 13/155007 |
Document ID | / |
Family ID | 47292160 |
Filed Date | 2012-12-13 |
United States Patent
Application |
20120312546 |
Kind Code |
A1 |
Bussear; Terry R. ; et
al. |
December 13, 2012 |
WATER HAMMER MITIGATING FLOW CONTROL STRUCTURE AND METHOD
Abstract
A water hammer mitigating flow control structure for a downhole
completion including a tubular member configured for the downhole
environment. A valve member in operable communication with the
tubular member and positionable with respect to the tubular member
to allow or prevent fluid movement through the tubular member. An
absorber in operable communication with the valve member and
configured to allow movement of the valve member the movement
absorbing a pressure rise against the valve member in use. Also
included is a method for mitigating water hammer in a flow control
structure for a downhole completion
Inventors: |
Bussear; Terry R.; (Spring,
TX) ; Murphy; Keith J.; (Simsbury, CT) |
Assignee: |
BAKER HUGHES INCORPORATED
Houston
TX
|
Family ID: |
47292160 |
Appl. No.: |
13/155007 |
Filed: |
June 7, 2011 |
Current U.S.
Class: |
166/373 ;
166/113 |
Current CPC
Class: |
E21B 34/06 20130101 |
Class at
Publication: |
166/373 ;
166/113 |
International
Class: |
E21B 34/06 20060101
E21B034/06 |
Claims
1. A water hammer mitigating flow control structure for a downhole
completion comprising: a tubular member configured for the downhole
environment; a valve member in operable communication with the
tubular member and positionable with respect to the tubular member
to allow or prevent fluid movement through the tubular member; and
an absorber in operable communication with the valve member and
configured to allow movement of the valve member the movement
absorbing a pressure rise against the valve member in use.
2. A water hammer mitigating flow control structure as claimed in
claim 1 wherein the valve member is a flapper valve.
3. A water hammer mitigating flow control structure as claimed in
claim 1 wherein the valve member is a ball valve.
4. A water hammer mitigating flow control structure as claimed in
claim 1 wherein the absorber is of constant rate.
5. A water hammer mitigating flow control structure as claimed in
claim 1 wherein the absorber is of variable rate.
6. A water hammer mitigating flow control structure as claimed in
claim 1 wherein the absorber is positioned downstream of fluid flow
relative to the valve member.
7. A water hammer mitigating flow control structure as claimed in
claim 1 wherein the absorber is positioned both upstream and
downstream of the valve member.
8. A water hammer mitigating flow control structure as claimed in
claim 7 wherein the absorber is two absorbers with one positioned
upstream and one positioned downstream of the valve member.
9. A water hammer mitigating flow control structure as claimed in
claim 1 wherein the absorber is a spring.
10. A water hammer mitigating flow control structure as claimed in
claim 9 wherein the spring is a coil spring.
11. A water hammer mitigating flow control structure as claimed in
claim 1 wherein the absorber is a gas charged chamber.
12. A water hammer mitigating flow control structure as claimed in
claim 1 wherein the absorber further includes a dash pot.
13. A water hammer mitigating flow control structure as claimed in
claim 12 wherein the dash pot is single acting.
14. A water hammer mitigating flow control structure as claimed in
claim 1 wherein the structure further includes a housing radially
adjacent the tubular member having one or more openings therein
that are covered until the tubular member is moved following a
pressure rise against the valve member in use.
15. A water hammer mitigating flow control structure as claimed in
claim 14 wherein the one or more openings absorb pressure when
exposed to fluid pressure subsequent to the valve member
experiencing a pressure rise in use.
16. A water hammer mitigating flow control structure as claimed in
claim 1 wherein the pressure rise is an origination or a reflection
of a tube wave.
17. A method for mitigating water hammer in a flow control
structure for a downhole completion comprising: allowing a valve
member to move relative to a tubular member with which the valve
member is operable to allow or prevent fluid movement through the
tubular member; absorbing a pressure rise against the valve member
with the movement.
18. A method for mitigating water hammer in a flow control
structure as claimed in claim 17 wherein the absorbing includes
deforming a spring.
19. A method for mitigating water hammer in a flow control
structure as claimed in claim 17 wherein the deforming includes
deforming a spring at a downstream position relative to the valve
member.
20. A method for mitigating water hammer in a flow control
structure as claimed in claim 17 wherein the deforming includes
deforming a spring at both downstream and upstream positions
relative to the valve member.
21. A method for mitigating water hammer in a flow control
structure as claimed in claim 17 wherein upon deforming the spring
in the downstream position, one or more openings in a housing of
the structure are uncovered.
22. A method for mitigating water hammer in a flow control
structure as claimed in claim 17 wherein the absorbing includes a
rebound and the rebound is slowed.
Description
BACKGROUND
[0001] For many industries where fluids are managed in pipelines of
various sorts and with actuable valves to permit and prevent fluid
flow, water hammer is a problem. The commonly termed water hammer
is a tube wave created when a flow of fluid is suddenly stopped by
a structure such as a valve. Upstream of the valve, fluid continues
to move into the closed valve, increasing pressure in a local
volume of fluid, which pressure propagates as a wave back in the
upstream direction potentially causing damage as it propagates and
when it reflects off other structures. Downstream of the valve the
fluid also continues to move thereby creating a localized
low-pressure in the fluid, which also can propagate as a wave in
the downstream direction. In extreme cases, cavitation can occur at
the downstream side of the valve with all of the intrinsic problems
that are known to practitioners.
[0002] In the drilling and completion arts, water hammer can be a
significant problem for a number of different components of
downhole systems such as safety valves for example. Means to
address water hammer would be well received by the art.
SUMMARY
[0003] A water hammer mitigating flow control structure for a
downhole completion including a tubular member configured for the
downhole environment; a valve member in operable communication with
the tubular member and positionable with respect to the tubular
member to allow or prevent fluid movement through the tubular
member; and an absorber in operable communication with the valve
member and configured to allow movement of the valve member the
movement absorbing a pressure rise against the valve member in
use.
[0004] A method for mitigating water hammer in a flow control
structure for a downhole completion including allowing a valve
member to move relative to a tubular member with which the valve
member is operable to allow or prevent fluid movement through the
tubular member; absorbing a pressure rise against the valve member
with the movement.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] Referring now to the drawings wherein like elements are
numbered alike in the several Figures:
[0006] FIG. 1 is a schematic view of one embodiment of a flow
control valve configured to mitigate water hammer in a position
open to flow;
[0007] FIG. 2 is a schematic view of the embodiment of FIG. 1 in a
reactive position following closure of the valve;
[0008] FIG. 3 is a schematic view of another embodiment of a flow
control valve configured to mitigate water hammer; and
[0009] FIG. 4 is a schematic view of another embodiment of a flow
control valve configured to mitigate water hammer.
DETAILED DESCRIPTION
[0010] In each of the following embodiments it is to be noted that
the "ringing" of the water hammer effect is mitigated. In some
applications the most important place to mitigate that ringing is
where the formation is directly exposed thereto. For example, in an
injection system, a ringing downhole of the injection valve is
detrimental to the formation. Mitigation of the ringing downhole of
the valve would accordingly be of paramount importance. Ringing in
other parts of the system may also however be of detrimental effect
and might advantageously be mitigated as well. Some of the
embodiments below will mitigate water hammer in either or both
directions.
[0011] Referring to FIG. 1, a first embodiment of a flow control
structure 10 configured to mitigate water hammer is schematically
illustrated. The structure 10 includes a tubular member 12, a valve
member 14 and an absorber 16 that together allow for a mitigation
in the origination of a tube wave upon closure of the valve or a
mitigation of the reflection of a tube wave originated at the valve
member 14 earlier in time or originated elsewhere in a system in
which the structure 10 is installed. The above noted components may
be disposed within a housing 18. The tubular member is, in the
embodiment illustrated in FIGS. 1 and 2, sealed to an inside
surface 20 of housing 18 with one or more seals 22 such as o-rings,
or other similar configurations capable of providing a sliding seal
against a surface such as surface 20. As illustrated there are
three seals 22 but it will be understood that more or fewer could
be employed without departing from the invention. Disposed in
operable communication with the tubular member 12 is valve 14,
which as illustrated is a ball valve but could be of other
structure including but not limited to a flapper, illustrated in
conjunction with the embodiment of FIG. 4, discussed hereunder. In
FIG. 1 the absorber 16 is shown both upstream and downstream of the
valve member 14 but it will be understood that it is contemplated
that only upstream or only downstream locations of the absorber
will not depart from the invention. Further it is to be noted that
the absorber may operate in compression, extension or both
depending upon application. It is also to be appreciated that it is
the valve member that need be movable and that this can occur with
the tubular member as illustrated in FIGS. 1 and 2 or can occur
within the tubular member where that member is fixed and the
absorber is in contact with the valve member.
[0012] Returning to discussion of FIG. 1 directly, it will be noted
that a means for actuating the valve member is provided in the form
of a hydraulic line 24. This is but one embodiment of means to
actuate the valve member and others are contemplated such as
electromagnetic means, pneumatic means, mechanical shifting means,
etc. The particular means of actuating the valve member does not
impact the operation of the invention.
[0013] It will be appreciated from the view of FIG. 1 that with the
valve member open, fluid will flow (see arrows 26) through the
device substantially unimpeded. When the valve member 14 is
actuated to the closed position (FIG. 2) however, the force of
fluid 26 causes a pressure thereof to build against the closed
valve member 14. It is this pressure build up that originates a
tube wave that will reflect from the valve member 14 back along a
tubing 28 in the upstream direction to potentially do damage to
components therealong. Because of the construction of the
embodiment of FIGS. 1 and 2, the tube wave originated by the
actuation of the valve member 14 to the closed position will be
substantially mitigated due to the ability of the valve member 14
to move in the downstream direction. Since the energy of the tube
wave comes from the pressure buildup against a member and the
reflection of that energy back in the direction from which it came,
the movement of the member against which pressure would naturally
build will mitigate the ultimate energy buildup and reflection.
Accordingly the resulting wave is in fact mitigated. Further, the
same thing will happen if the valve member 14 is impacted by a tube
wave generated somewhere else in the tubing. This then results in
mitigation of that tube wave also hence positively affecting the
entire system. Because in one embodiment the absorber exists on
both upstream and downstream positions relative to the valve member
14, the device will operate on tube waves originating or
propagating in or from either direction. This also can be the case
however if the absorber is only on one side of the valve member 14
depending upon how the absorber is set up, i.e. with compressive
capability, extensive capability or both and the position of the
absorber at rest relative to the housing 18.
[0014] Although the absorber 16 is illustrated as a coil spring, it
is contemplated that the absorber 16 may comprise other
configurations such as a gas spring, a rubber spring, capillary
spring or other resilient configurations. It is further noted that
the spring rate may be constant or variable in embodiments. In each
iteration, the valve member 14 will be allowed to move in at least
one direction and in some embodiments will be allowed to move in
both directions, and in either case, will be decelerated to a stop
gradually after movement begins pursuant to a valve closure.
[0015] It is noted that most of the discussion herein is related to
the pressure rise on the upstream side of the valve member 14. It
will be appreciated however that the same action that mitigated
that rise on the upstream side of the valve member will mitigate
the low-pressure event caused at the downstream side of the valve
member in a prior art system. This is because the valve member is
following the fluid in the downstream direction and therefore not
allowing the fluid to pull the pressure down in the local area
immediately downstream of the valve member 14, as it would do in a
fixed valve member prior art system.
[0016] In another embodiment, referring to FIG. 3, the resilient
member is not needed and rather friction alone is relied upon to
cause a controlled deceleration of the movement of the valve member
14. Since it is the reduction in the speed of deceleration of the
fluid flowing through the tubular that acts to reduce the
origination of or reflection of a tube wave, this can be
accomplished with a bore in housing 18 in which the valve member
may slide providing that the valve member 14 will slide more
rapidly upon closure of the valve member and then progressively
slow down to a stop. Such an embodiment may be configured as a
frustoconical polished bore 30 with the smaller dimensioned end 32
of the bore being downstream of the valve member 14. Upon closure
of the valve member, the member 14 will move in the downstream
direction (arrow) under the influence of the flowing fluid. As the
valve member 14 is entering a smaller and smaller dimension range
of the frustocone, friction on the valve member is progressively
higher. The valve will hence slow to a stop smoothly and generate
and or reflect little or no tube wave. In this embodiment, the
valve member 14 will not reset itself as it does in the embodiments
that use a resilient member.
[0017] In another embodiment, referring to FIG. 4, the foregoing
embodiments are modified to include one or more openings 30 in the
housing 18. In this embodiment the tubular member 12 and seal(s) 22
cover the one or more openings 30 that extend to a chambers that
allow for pressure diffusion such as atmospheric chambers, or
"bags" of fluid impermeable material. Upon the actuation of the
valve member 14 (actuated in any of the known ways to actuate a
flow control valve, in the illustrated case a flapper or a ball
valve), the valve member 14 will move in the downstream direction
as did the embodiment of FIG. 1 but in this case, the tubular
member 12, moving with the valve member 14 will uncover the one or
more openings 30 thereby providing a pressure diffusion pathway for
the building pressure of the fluid flow due to the closure of the
valve member 14. This action in combination with the movement of
the valve member 14, will act to mitigate the origination and/or
reflection of a tube wave. Depending upon the application, if there
is no prohibition to fluid flow into an annulus of the
configuration, the openings 30 may open to that annulus. In other
configurations, such as a safety valve for example, a fluid pathway
to the annulus would be prohibited and hence this embodiment could
not be used for such an application.
[0018] It is further noted that each embodiment where there is a
resilient absorber, a dashpot, and particularly a single acting
dashpot that allows rapid initial movement but slows the return
movement of the valve member, could be added to damp the resilience
particularly upon the rebound stroke after compression of the
absorber due to valve closure.
[0019] While one or more embodiments have been shown and described,
modifications and substitutions may be made thereto without
departing from the spirit and scope of the invention. Accordingly,
it is to be understood that the present invention has been
described by way of illustrations and not limitation.
* * * * *