U.S. patent application number 14/325873 was filed with the patent office on 2016-01-14 for electrically operated valve and method thereof.
This patent application is currently assigned to BAKER HUGHES INCORPORATED. The applicant listed for this patent is Graeme M. Kelbie, Gordon R. Mackenzie. Invention is credited to Graeme M. Kelbie, Gordon R. Mackenzie.
Application Number | 20160010427 14/325873 |
Document ID | / |
Family ID | 55064658 |
Filed Date | 2016-01-14 |
United States Patent
Application |
20160010427 |
Kind Code |
A1 |
Kelbie; Graeme M. ; et
al. |
January 14, 2016 |
ELECTRICALLY OPERATED VALVE AND METHOD THEREOF
Abstract
A downhole tool assembly includes a tubular having a flowbore
extending along a longitudinal axis of the tubular. An electric
actuating mechanism supported by the tubular and distanced from the
longitudinal axis of the tubular; and, a valve assembly connected
to the tubular and fluidically connected to the flowbore. The valve
assembly including: an outer portion having at least one port; and
an electrically actuated inner portion concentrically positioned
within the outer portion and operable by the actuating mechanism to
selectively block the at least one port in a first condition of the
valve assembly and unblock the at least one port in a second
condition of the valve assembly. A method of actuating a valve
assembly in a downhole tubular.
Inventors: |
Kelbie; Graeme M.; (Cypress,
TX) ; Mackenzie; Gordon R.; (Cypress, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Kelbie; Graeme M.
Mackenzie; Gordon R. |
Cypress
Cypress |
TX
TX |
US
US |
|
|
Assignee: |
BAKER HUGHES INCORPORATED
Houston
TX
|
Family ID: |
55064658 |
Appl. No.: |
14/325873 |
Filed: |
July 8, 2014 |
Current U.S.
Class: |
166/373 ;
166/66.6 |
Current CPC
Class: |
E21B 34/066 20130101;
E21B 34/16 20130101 |
International
Class: |
E21B 34/06 20060101
E21B034/06; E21B 34/16 20060101 E21B034/16 |
Claims
1. A downhole tool assembly comprising: a tubular having a flowbore
extending along a longitudinal axis of the tubular; an electric
actuating mechanism supported by the tubular and distanced from the
longitudinal axis of the tubular; and, a valve assembly connected
to the tubular and fluidically connected to the flowbore, the valve
assembly including: an outer portion having at least one port; and
an electrically actuated inner portion concentrically positioned
within the outer portion and operable by the actuating mechanism to
selectively block the at least one port in a first condition of the
valve assembly and unblock the at least one port in a second
condition of the valve assembly.
2. The downhole tool assembly of claim 1 wherein the inner portion
is further movable to selectively block only a portion of the at
least one port in a third condition of the valve assembly, leaving
a remainder of the at least one port unblocked in the third
condition.
3. The downhole tool assembly of claim 1 wherein the inner portion
further includes at least one aperture configured to be selectively
aligned and misaligned with the at least one port of the outer
portion.
4. The downhole tool assembly of claim 1 wherein the inner portion
is configured to be longitudinally shiftable relative to the outer
portion.
5. The downhole tool assembly of claim 4 wherein the at least one
port in the outer portion includes a plurality of ports, at least
two of the plurality of ports positioned at longitudinally discrete
locations along the outer portion.
6. The downhole tool assembly of claim 4 wherein the actuating
mechanism includes a screw rod rotatable by a motor, the inner
portion including a threaded aperture configured to longitudinally
shift the inner portion upon rotation of the screw rod.
7. The downhole tool assembly of claim 6 wherein the threaded
aperture is located within a peripheral wall of the inner
portion.
8. The downhole tool assembly of claim 1 wherein the inner portion
is configured to be rotatable and substantially longitudinally
stationary within the outer portion.
9. The downhole tool assembly of claim 8 wherein a surface of the
inner portion includes gear teeth and the actuating mechanism
includes a driving gear having teeth engageable with the gear teeth
of the surface of the inner portion.
10. The downhole tool assembly of claim 9 wherein the gear teeth of
the inner portion are located on a first section of the inner
portion, and a second section of the inner portion further includes
at least one aperture configured to be selectively aligned and
misaligned with the at least one portion of the outer portion.
11. The downhole tool assembly of claim 1 further comprising an
electric motor operating the actuating mechanism, the electric
motor substantially positioned within a peripheral wall of the
tubular.
12. The downhole tool assembly of claim 11 wherein the motor is
configured to receive electricity from a surface location.
13. The downhole tool assembly of claim 1 further comprising a
power generating member, wherein flow through the tubular is used
to generate power in the power generating member.
14. The downhole tool assembly of claim 1 further comprising a
sensor configured to detect a condition indicative of a need to
activate the valve assembly, and a motor configured to actuate the
actuating mechanism and valve assembly in response to the sensed
condition.
15. The downhole tool assembly of claim 1 wherein the outer portion
and the tubular substantially share the longitudinal axis.
16. A method of actuating a valve assembly in a downhole tubular,
the method comprising: inserting a tubular having a flowbore into a
borehole; employing a peripherally positioned electric motor within
the tubular; actuating an electrically activated valve assembly
with the motor, the valve assembly including an outer portion
having at least one port and an inner portion movably configured
within the outer portion; and, selectively moving the inner portion
to block the at least one port in a first condition of the valve
assembly and selectively moving the inner portion to expose the at
least one port in a second condition of the valve assembly; wherein
fluid flow through the tubular during both the first and second
conditions of the valve assembly is not blocked.
17. The method of claim 16 further comprising selectively moving
the inner portion to block a portion of the at least one port and
expose a portion of the at least one port in a third condition of
the valve assembly and selectively maintaining the valve assembly
in the third condition.
18. The method of claim 16 wherein selectively moving the inner
portion includes longitudinally moving the inner portion relative
to a longitudinal axis of the tubular by employing the power source
to rotate a screw rod within a threaded aperture within a
peripheral wall of the inner portion.
19. The method of claim 16 wherein selectively moving the inner
portion includes rotatably moving the inner portion by employing
the motor to rotate a driving gear meshing with gear teeth on a
surface of the inner portion.
20. The method of claim 16 further comprising harvesting energy
from fluid flow through the tubular to operate the motor.
Description
BACKGROUND
[0001] In the completion and production industry for natural
resources, the formation of boreholes/completions for the purpose
of production or injection of fluid is common. The
boreholes/completions are used for exploration or extraction of
natural resources such as hydrocarbons, oil, gas, water, and
alternatively for CO2 sequestration. Coiled tubing or string is run
into the borehole/completion for varying purposes and valves, such
as circulation valves, have been used on the tubing or string to
enable circulation of fluids between the inside and the outside of
the tubing. Such valves are typically mechanically operable
including ball-activated features and pressure-operated
features.
[0002] The art would be receptive to improved alternative devices
and methods for operating a valve within a borehole/completion.
BRIEF DESCRIPTION
[0003] A downhole tool assembly includes a tubular having a
flowbore extending along a longitudinal axis of the tubular; an
electric actuating mechanism supported by the tubular and distanced
from the longitudinal axis of the tubular; and, a valve assembly
connected to the tubular and fluidically connected to the flowbore,
the valve assembly including: an outer portion having at least one
port; and an electrically actuated inner portion concentrically
positioned within the outer portion and operable by the actuating
mechanism to selectively block the at least one port in a first
condition of the valve assembly and unblock the at least one port
in a second condition of the valve assembly.
[0004] A method of actuating a valve assembly in a downhole
tubular, the method includes inserting a tubular having a flowbore
into a borehole; employing a peripherally positioned electric motor
within the tubular; actuating an electrically activated valve
assembly with the motor, the valve assembly including an outer
portion having at least one port and an inner portion movably
configured within the outer portion; and, selectively moving the
inner portion to block the at least one port in a first condition
of the valve assembly and selectively moving the inner portion to
expose the at least one port in a second condition of the valve
assembly; wherein fluid flow through the tubular during both the
first and second conditions of the valve assembly is not
blocked.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The following descriptions should not be considered limiting
in any way. With reference to the accompanying drawings, like
elements are numbered alike:
[0006] FIG. 1 shows a schematic diagram of a downhole tool assembly
in a borehole incorporating an exemplary electrically operable
valve assembly;
[0007] FIG. 2 shows a cross sectional exploded side view of an
exemplary embodiment of the downhole tool assembly of FIG. 1;
[0008] FIG. 3 shows cross-sectional side view of an exemplary
embodiment of an axially shiftable valve assembly;
[0009] FIG. 4 shows a cross-sectional view of the axially shiftable
valve assembly taken along line 4-4 of FIG. 3;
[0010] FIG. 5 shows a cross sectional side view of an exemplary
embodiment of a rotatably adjustable valve assembly;
[0011] FIG. 6 shows a cross-sectional view of the rotatably
adjustable valve assembly taken along line 6-6 of FIG. 5;
[0012] FIG. 7 shows a side plan view of an exemplary inner portion
of the valve assembly of FIG. 5; and,
[0013] FIGS. 8A-8C show cross sectional views of alternate
exemplary embodiments of a power generation sub for the downhole
tool assembly of FIG. 2.
DETAILED DESCRIPTION
[0014] A detailed description of one or more embodiments of the
disclosed apparatus and method are presented herein by way of
exemplification and not limitation with reference to the
Figures.
[0015] FIG. 1 shows a downhole tool assembly 100 positioned within
a borehole 10 lined with a casing 12. The borehole 10 has a
generally vertical section and may further include a deviated or
horizontal section 20. Alternatively, the borehole 10 is an
open-type borehole where the formation wall 16 is not lined with
casing 12. The downhole tool assembly 100 includes a tubular string
14, such as, but not limited to, coiled tubing, production string,
and drilling string. The string 14 includes any number of connected
tubing pieces and may be spoolable onto a reel (not shown) provided
at a surface location 22. At a downhole end 24 of the string 14, a
tool 18 may be carried for performing a downhole operation. While
illustrated at the downhole end 24, one or more tools 18 may be
provided anywhere between the downhole end 24 and surface location
22. Alternatively, the string 14 need not include any tool 18. The
string 14 may also be used primarily for well production stages
using coiled tubing, where the valve assembly 40 is employed for
circulating or redirecting production fluids as needed to direct
such fluids to surface, bypass blockages, etc., or for injection of
stimulating or fracturing fluids as needed from an interior to an
exterior of the string 14.
[0016] A power source 28 providing electrical energy may be
provided at the surface location 22, and sends an electrical
signal, such as via line 30. A surface control unit 38 is used to
electrically control operation of a valve assembly 40, such as a
circulation valve, by using a motor powered by the power source 28
or a power generation sub as will be further described below.
Whenever valve operation is necessary, the valve assembly 40 is
activated by an actuation mechanism to move to a full or partially
open condition based on required flow regimes to allow for
circulation of fluids from inside to outside, outside to inside,
downhole to uphole, or uphole to downhole, either as a one off
operation or multi-repeated cycles.
[0017] While the valve assembly 40 may be controlled via the
control unit 38 at any time, whether programmed or by operator
input, in an exemplary embodiment of the downhole tool assembly
100, sensor modules 32 may also be directly incorporated into the
string 14 or tool 18 to detect changes in the environment of the
string 14 within the borehole 10 to indicate when an operation of a
circulation valve assembly 40 is necessary. The sensor module 32
could be incorporated into a logging bottom hole assembly 34,
provided separately along interconnections of the string 14 or
other locations along the string 14, or provided within the tool
18. The sensor module 32 may contain sensors 36, circuitry, and
processing software and algorithms relating to environment of the
borehole indicative of a necessity for operation of a valve
assembly 40. Such parameters may include pressure, flow speed, and
other measurements related to the environment of the string 14.
Signals from sensors 36 in the sensor module 32 or sensors 36
provided elsewhere along the string 14 are either processed by the
sensor module 32, sent to a surface location 22 such as surface
control unit 38 for operator evaluation, or directly to a valve
assembly 40 for immediate or subsequent action. The surface control
unit 38 or processor may receive signals from the sensors 36 and
processes such signals according to programmed instructions
provided to the surface control unit 38. The surface control unit
38 may also display information on a display/monitor utilized by an
operator. The surface control unit 38 may include a computer or a
microprocessor-based processing system, memory for storing programs
or models and data, a recorder for recording data, and other
peripherals. The control unit 38 may be adapted to notify the
operator when operating conditions indicate a need for circulation
or other valve operation. The surface control unit 38 may also be
used for other operations of the string 14 and tool 18 not
described herein. A communication sub (not shown) may obtain the
signals and measurements and transfers the signals, using two-way
telemetry, for example, to be processed at the surface location 22.
Alternatively, the signals can be processed using a downhole
processor in the tool 18 or sensor module 32. In the event a signal
is sent indicating a need for circulation or other valve operation,
the valve assembly 40 is electrically activated.
[0018] The selective valve operation does not impede operation of
the tool(s) 18, string 14, or any downhole procedure. Furthermore,
as will be further described below, even when the valve assembly 40
is activated, flow through a flowbore 42 of the string 14 is not
blocked or restricted so as to allow for flow therethrough for use
by the tool 18 or downhole operations requiring such flow, such as
production through the coiled tubing of the string 14.
[0019] Turning now to FIG. 2, the downhole tool assembly 100 is
shown including the valve assembly 40. The string 14 includes a
tubular wall 44 surrounding the flowbore 42. While the valve
assembly 40 is depicted downhole of the string 14, additional
lengths of the string 14 may also be connected downhole of the
valve assembly 40. Additionally, multiple valve assemblies 40 may
be provided along the string 14 as exemplified in FIG. 1.
[0020] An exemplary embodiment of the downhole tool assembly 100
includes a logging bottom hole assembly ("BHA") 34. The logging BHA
may be a separate component from the valve assembly 40. Also
included in the downhole tool assembly is a motor 46, which may be
incorporated into a power supply sub 48, and an electrically
activated valve assembly 40.
[0021] The logging BHA 34 is attachable to the string 14. The
logging BHA 34 includes an uphole end 54 connected to the string
14, and a downhole end 56. The logging BHA 34 also includes
flowthrough, such that a flowbore 58 of the logging BHA 34 is in
fluid communication with the flowbore 42 of the string 14. The
logging BHA 34 may create any type of geophysical log by making at
least one type of measurement of rock or fluid property in the
borehole 10 or within the flowbore 58 of the logging BHA 34 itself
The measurements are taken using at least one type of sensor,
including, but not limited to, sensors to measure pressure,
temperature, spontaneous potential, and radiation, as well as a
variety of sensors such as acoustic (sonic), electric, inductive,
magnetic resonance, etc. One of the sensors in the logging BHA 34
may be the sensor 36 that detects environmental conditions within
the borehole 10. The data from the measurements secured by the
logging BHA 34 may be recorded at the surface control unit 38, or
alternatively the logging BHA 34 may include a memory storage unit
for subsequent creation of a well log. Since the information from
the logging BHA 34 can be used by operators to gain an
understanding of the borehole 10 for any desired downhole
operation, the logging BHA 34 need not be directly part of the
valve assembly 40 even if information obtained from the logging BHA
34 is utilized by the valve assembly 40. Alternatively, the valve
assembly 40 may be electrically operated using signals initiated by
an operator or from other sensors 36, 28 as previously
described.
[0022] Connected downhole of string 14, and the logging BHA 34 if
utilized, is a power supply sub 48. The power supply sub 48
includes an uphole end 60 and a downhole end 62 and includes
flowthrough via a flowbore 66. The uphole end 60 of the power
supply sub 48 is connected downhole of the logging BHA 34 or string
14. In one exemplary embodiment, a conductor 64 passes through the
string 14, logging BHA 34, and into the power supply sub 48. The
conductor 64 is formed of one or more insulated wires or bundles of
wires adapted to convey power and/or data, and may be included with
or part of the signal conducting line 30 that delivers signals from
the surface location 22 to motor 46. The conductor 64 can include
metal wires, or alternatively other carriers such as fiber optic
cables that may be provided in a tubing encapsulated cable ("TEC")
such as an armored metal clad water sealed cable. The conductor 64
can deliver the signal provided by the sensors 28 or operator input
previously described, as well as carry the signals from the
downhole sensors 36. Additionally, by use of either direct or
alternating current transmittal through the conductor 64, the power
supply sub 48 is capable of providing sufficient power to operate
the valve assembly 40 connected downhole of the power supply sub
48. The conductor 64 is either provided within a protective channel
(not shown) incorporated within the string 14 or passed through the
flowbores 42, 58 of the string 14 and logging BHA 34, such as via a
wireline. Advantages of using conductor 64 to conduct current from
the surface 22 include the ability to conduct high amounts of
electrical energy from the surface 22 and the supply from the
surface 22 is relatively unlimited.
[0023] The power supply sub 48 is a tubular that peripherally
supports the motor 46 and may alternatively or additionally include
a power storage unit such as one or more batteries 68. Batteries 68
can be used as a local source of power for downhole electrical
devices, such as the electrically activated valve 40 or a tool 18,
but the batteries 68 must be arranged to fit within space
constraints that exist within the borehole 10 and string 14.
Electrically recharging the battery 68 can occur through the
conductor 64, and replacing the battery 68, if required, may be
accomplished via a wireline operation or upon retrieval of the
battery 68 from the borehole 10.
[0024] When necessary to open the valve assembly 40, or close the
valve assembly 40, such as determined by a surface operator or via
the logging BHA 34 or sensor 36 or 28 that a condition within or
exterior to the string 14 has necessitated valve operation, then
the power supply sub 48 will utilize an actuating mechanism linked
to the motor 46 to activate the electrically operated valve
assembly 40. The electrically operated valve assembly 40 shares
substantially the same flowpath, and likewise may share
substantially the same longitudinal axis when interconnected with
the power supply sub 48, logging BHA 34, and string 14. While the
valve assembly 40, power supply sub 48, and logging BHA 34 have
been described and illustrated as separate elements, another
exemplary embodiment would include the integration of any
combination of such subs, although separating the components into
different subs generally eases replacement of defective parts.
Also, while the different subs are described as interconnected, it
should be understood that the elements may be separated from each
other by any additional lengths of string 14 or connectors.
[0025] When actuated by the power supply sub 48, the electrically
operated valve assembly 40 will either open or close or be
positioned at an interim location between fully opened and fully
closed. The valve assembly 40 is accessible to the flow bore 42 of
the assembly 100, but does not block or restrict the flow bore 104
even when in use, nor does it interrupt the normal flow through the
flow bore 104 and string 14. Thus, any downhole tools, such as tool
18, which depend on the flow through the flow bore 42, still
receive the flow. Also, the downhole tool assembly 100 is suited
for well production through the flow bore 42, since the flow bore
42 is not blocked by any of the above-described portions of the
assembly 100.
[0026] As depicted in FIGS. 3-4, one exemplary embodiment of the
valve assembly 140 includes a longitudinally displaceable or
axially shiftable inner portion 110 of the valve assembly 140 that
covers/blocks or uncovers/exposes at least one port 112 in an outer
portion 114 of the valve assembly 140. The outer portion 114 may be
connected with the tubular of the power supply sub 48 so as to
substantially share the same longitudinal axis as the power supply
sub 48 and downhole tool assembly 100 and to fluidically connect
with the flowbore 42 of the downhole tool assembly 100. One
exemplary embodiment of an actuating mechanism 115 to move the
inner portion 110 in an uphole or downhole direction includes a
screw rod 116 rotated by motor 46 within a threaded aperture 118 in
the inner portion 110. The inner portion 110 has a substantially
tubular-shaped cross-section, with at least one section 120 of the
inner portion 110 sized to accommodate the threaded aperture 118.
The section 120 may have a larger peripheral wall thickness than a
wall thickness of the remainder of the peripheral wall. As can be
mechanically understood, rotation of the screw rod 116 in a first
direction will move the inner portion 110 in a downhole direction
(further from surface location 22), while rotation of the screw rod
116 in a second direction, opposite the first direction, will move
the inner portion 110 in an uphole direction. The outer portion 114
may include two or more longitudinally spaced ports 112 such that
movement of the inner portion 110 in the uphole or downhole
direction provides more or less fluid access between the flow bore
42 and the annulus surrounding the downhole tool assembly 100. For
example, if the inner portion is positioned as shown in FIG. 3 in a
first condition, the valve assembly 140 is fully closed/blocked. If
the inner portion 110 is moved by the motor 46 to reveal all the
ports 112, then the valve assembly 140 is fully opened in a second
condition of the valve assembly 140. The valve assembly 140 may
further include any number of additional conditions between fully
closed and fully opened. For example, in the illustrated
embodiment, if one or more of the ports 112 are unblocked, but one
or more of the ports 112 are blocked, and then the motor 46 is
intentionally stopped to halt further movement of the inner portion
110, then the valve assembly 100 is in a partially opened position,
a third condition. The inner portion 110 may be positionable in any
of the port revealing positions described above, and may then be
subsequently partially or fully closed or fully opened by selecting
the appropriate rotation direction of the screw rod 116. While the
inner portion 110 has been depicted to reveal the ports 112
successively by moving the inner portion 110 in an uphole
direction, alternatively the inner portion 110 could be arranged
such that the inner portion 110 must move in a downhole direction
to successively reveal the ports 112. Also, while discrete axially
spaced ports 112 have been illustrated, the outer portion 114 may
alternatively include an elongated longitudinal slot where a third
condition (between fully opened and fully closed) is achieved by
halting the inner portion 110 at a position where the longitudinal
slot is both partially covered and partially revealed by the inner
portion 110. In still another exemplary embodiment, the inner
portion 110 may include apertures that align or misalign with the
ports 112 of the outer portion 114.
[0027] FIGS. 5-7 show an alternative arrangement of a valve
assembly 240 for rotatably moving the inner portion 210 relative to
the outer portion 214. An actuating mechanism 215 includes a gear
set 216 that meshes with a rotatable driving gear 218 which in turn
meshes with gear teeth 220 on a surface, such as an interior
surface 222, of the inner portion 210. The gear teeth 220 need only
be limited to a first section of the inner portion 210, while a
remainder of the surface 222 may be free of gear teeth 220. The
driving gear 218 is rotated in a first direction or an opposite
second direction, such as by rotation of motor shaft 224 fixedly
attached to an initial gear in the gear set 216. Rotation of the
driving gear 218 rotates the inner portion 210. The inner portion
210 may be axially constrained by uphole and downhole shoulders
230, 232 protruding radially inwardly from outer portion 214. The
inner portion 210 includes one or more windows 226 that are
alignable with or cover one or more ports 212 in the outer portion
214. As in the valve assembly 140, the valve assembly 240 is
configured to be selectively movable between a first condition in
which the valve ports 212 are fully covered by an imperforate
portion 228 of the inner portion 210, a second condition in which
the valve ports 212 are completely accessible to a flow bore 42 of
the downhole tool assembly 100, and a third condition in which the
valve ports 212 are only partially blocked by the imperforate
portion 228 of the inner portion 210.
[0028] In other exemplary embodiments, the power supply sub 48 may
include a downhole electrical generating mechanism 70 (FIGS. 8A-8D)
to continuously generate electricity and supply electricity as
needed to the motor 46 or a storage location, such as the
electrical generating apparatus described by U.S. Pat. No.
5,839,508 to Tubel et al, herein incorporated by reference in its
entirety. The electrical generating mechanism 70 may utilize the
power of passing fluid (hydraulic energy), magnetic field, a
turbine, spring energy, piezoelectrics, etc. When the power supply
sub 48 is employed as a power generation sub 72, power is
scavenged, or harvested, from sources of potential energy within
the borehole 10 including, but not limited to, fluids moving inside
the flowbore 66. The power generation sub 72 may harvest
vibrational energy, such as the vibrational energy harvesting
mechanism described by U.S. Patent Application 2009/0166045 to
Wetzel et al. The flow through the flowbore 66 is a source of
vibrational energy downhole, and vibration enhancement mechanisms
as described in Wetzel et al. may be added in the flowbore 66 to
produce a locally more turbulent flow. Additionally, vibrations
created by the tool 18 are also harvestable by the power generation
sub 72. When harvesting energy from the movement of fluid within
the flowbore 66, the fluid can be used to rotate a rotatable
element such as a turbine or a rotatable magnet within a coil. The
rotating turbine can be connected to an electrical generator that
communicates with an energy storage device, such as a battery 74.
Rotation of a magnet within a coil will induce magnetic flux on the
coil and a converter can convert AC electrical output to DC
electrical energy as needed. As shown in FIG. 3A, the electrical
generating mechanism 70 of the power generation sub 72 may occupy a
lateral passageway 76 so as not to block the main flowbore 66, or
may alternatively be positioned within an annulus 78 surrounding
the flowbore 66 as depicted in FIG. 3B. Alternatively, as shown in
FIG. 3C, hydraulic pressure from the surface 22 can be used to
generate power in an electrical generating mechanism 70 by
delivering fluid under pressure via a hydraulic line 80 to react
with the electrical generating mechanism 70.
[0029] In the embodiments described above, neither the valve
assembly 40, 140, 240 nor the actuating mechanism 115, 215 required
to actuate the valve assembly 40, 140, 240 block flow through the
flowbore of the downhole tool assembly 100. Any of the above
described embodiments of an electrically operated valve assembly
and power supply sub may be used in plurality and sections of
string 14 may be interposed therebetween. While fluid flow is
illustrated in one particular direction, it should be understood
that the fluid flow within the flowbores 42, 58, 66, 104 of the
above described exemplary embodiments may be in either uphole or
downhole direction depending upon the particular application of the
string.
[0030] A method of operating a valve assembly 40, 140, 240 in a
downhole tool assembly 100 includes inserting a tubular such as the
string 14 into the borehole 10, determining a need for opening or
blocking flow between the flowbore of the tubular and the annulus
between the tubular and the borehole 10, sending a signal to a
control unit 28 or motor 46 in response to the determined need,
actuating an electrically activated valve assembly 40, the valve
assembly 40 having a flow bore 104 fluidically connected to a
flowbore 42 of the tubular, and altering the flow between the
tubular and surrounding borehole 10 by operation of the valve
assembly 40. The method enables a partial opening of flow between
the flowbore and annulus. Flow through the flowbores 42, 104 of the
string 14 and valve assembly 40 is not blocked during activation
and non-activation of the valve assembly 40. The method further
includes generating power in a power generating sub 48.
[0031] While the invention has been described with reference to an
exemplary embodiment or embodiments, it will be understood by those
skilled in the art that various changes may be made and equivalents
may be substituted for elements thereof without departing from the
scope of the invention. In addition, many modifications may be made
to adapt a particular situation or material to the teachings of the
invention without departing from the essential scope thereof.
Therefore, it is intended that the invention not be limited to the
particular embodiment disclosed as the best mode contemplated for
carrying out this invention, but that the invention will include
all embodiments falling within the scope of the claims. Also, in
the drawings and the description, there have been disclosed
exemplary embodiments of the invention and, although specific terms
may have been employed, they are unless otherwise stated used in a
generic and descriptive sense only and not for purposes of
limitation, the scope of the invention therefore not being so
limited. Moreover, the use of the terms first, second, etc. do not
denote any order or importance, but rather the terms first, second,
etc. are used to distinguish one element from another. Furthermore,
the use of the terms a, an, etc. do not denote a limitation of
quantity, but rather denote the presence of at least one of the
referenced item.
* * * * *