U.S. patent application number 16/257183 was filed with the patent office on 2019-08-01 for rotating control devices and methods to detect pressure within rotating members.
This patent application is currently assigned to National Oilwell Varco, L.P.. The applicant listed for this patent is National Oilwell Varco, L.P.. Invention is credited to Dean Allen Bennett, Ajay V. Kulkarni, Yang Wang, Andoni Zagouris, II.
Application Number | 20190234173 16/257183 |
Document ID | / |
Family ID | 65576648 |
Filed Date | 2019-08-01 |
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United States Patent
Application |
20190234173 |
Kind Code |
A1 |
Bennett; Dean Allen ; et
al. |
August 1, 2019 |
Rotating Control Devices and Methods to Detect Pressure Within
Rotating Members
Abstract
A rotating control device includes a housing with a sensor port
extending to a central housing bore, a sensor in the port, and a
rotating sleeve assembly (RSA) extending within the central bore.
The RSA includes a sleeve configured to rotate relative to the
housing and a second bore coaxially aligned with the central bore
of the housing, A piston port in the sleeve extends to the second
bore, and a piston disposed in the piston port is configured to
reciprocate between a first position and a second position in
response to a change in pressure of fluid within the second bore.
The piston port and the piston are disposed at a location in the
rotating sleeve that passes the sensor periodically when the
rotating sleeve rotates; the sensor configured to detect the piston
when it rotates past the sensor and is in its second position.
Inventors: |
Bennett; Dean Allen;
(Missouri City, TX) ; Kulkarni; Ajay V.; (Sugar
Land, TX) ; Wang; Yang; (Houston, TX) ;
Zagouris, II; Andoni; (Conroe, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
National Oilwell Varco, L.P. |
Houston |
TX |
US |
|
|
Assignee: |
National Oilwell Varco,
L.P.
Houston
TX
|
Family ID: |
65576648 |
Appl. No.: |
16/257183 |
Filed: |
January 25, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62622411 |
Jan 26, 2018 |
|
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|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B 33/06 20130101;
E21B 33/0355 20130101; E21B 47/06 20130101; E21B 33/085 20130101;
E21B 44/00 20130101; E21B 34/16 20130101 |
International
Class: |
E21B 33/08 20060101
E21B033/08; E21B 47/06 20060101 E21B047/06; E21B 44/00 20060101
E21B044/00 |
Claims
1. A rotating control device for a well, the device comprising: a
housing having a through-bore extending along a central axis, a
housing wall, and a sensor disposed at a sensor position in the
housing and extending into the housing wall; a sleeve comprising a
sleeve bore aligned with the central axis and configured to rotate
about the central axis, within the through-bore of the housing; and
a pressure-responsive assembly coupled to the sleeve and configured
to generate a response to a pressure of fluid within the sleeve
bore, the pressure-responsive assembly coupled to the sleeve at a
location such that it passes the sensor position periodically as
the sleeve rotates within the through-bore; wherein the sensor is
configured to detect the response of the pressure-responsive
assembly. wherein pressure-responsive assembly includes a
pressure-responsive element in fluid communication with the sleeve
bore; and wherein the pressure-responsive element is configured to
be free of sliding engagement with the sleeve.
2. The rotating control device of claim 1 wherein the
pressure-responsive assembly comprises a first piston slidingly
disposed inside a piston cartridge and configured to move from a
first position to a second position relative to the piston
cartridge in response to an activation pressure in the fluid within
the sleeve; wherein the sensor is configured to detect the presence
of the first piston when the first piston is in the second position
and passes the sensor position; and wherein the piston is separated
from the sleeve by the piston cartridge.
3. The rotating control device of claim 2 wherein the sleeve
further comprises an outer surface, and a first piston port
extending from the sleeve outer surface, the first piston port in
fluid communication with the sleeve bore; wherein the
pressure-responsive assembly is disposed in the first piston port
with the first piston in fluid communication with the sleeve bore;
and wherein the first piston is configured to slide without
contacting the first piston port.
4. The rotating control device of claim 3 further comprising a
burst disc coupled to the piston cartridge and disposed to seal the
first piston from the fluid within the sleeve until the fluid
reaches or exceeds a prescribed pressure.
5. The rotating control device of claim 3 further comprising a
plurality of pressure-responsive assemblies, each
pressure-responsive assembly coupled to the sleeve at a different
location such that it passes the sensor position periodically as
the sleeve rotates within the through-bore; wherein each
pressure-responsive assembly of the plurality is configured to
generate a response to a particular pressure of the fluid within
the sleeve bore; and wherein the sensor is configured to detect the
responses of each of the plurality of pressure-responsive
assemblies.
6. The rotating control device of claim 1 wherein the
pressure-responsive assembly comprises a transducer configured to
emit a first wireless signal including pressure data corresponding
to the pressure of the fluid within the sleeve; and wherein the
sensor comprises a receiver and transmitter device configured to
receive the pressure data from the transducer when the transducer
is within a detection range of the sensor, and wherein the receiver
and transmitter device is configured to transmit the pressure data
beyond the housing.
7. A rotating control device for a well, the device comprising: a
housing comprising a first bore extending along a central axis, and
a sensor port extending to the first bore, the sensor port disposed
at a discrete circumferential location about the central axis; a
sensor disposed within the sensor port; and a rotating sleeve
assembly (RSA) extending at least partially within the first bore
and, comprising: a rotating sleeve configured to rotate about the
central axis relative to the housing and comprising a sleeve outer
surface, a second bore coaxially aligned with the first bore, and a
first piston port extending from the sleeve outer surface to the
second bore; and a first piston disposed within the first piston
port and configured to reciprocate between a first position and a
second position in response to a change in pressure of fluid within
the second bore; wherein the first piston port and the first piston
are disposed at a location in the rotating sleeve that passes the
sensor periodically when the rotating sleeve rotates relative to
the housing; and wherein the sensor is configured to detect the
first piston when the first piston rotates past the sensor, and the
first piston is in its second position.
8. The device of claim 7 wherein the rotating sleeve further
comprises a plurality of piston ports, including the first piston
port, extending from the outer surface to the second bore; wherein
the RSA further comprises a plurality of pistons, including the
first piston, each piston disposed within one of the plurality of
piston ports and configured to reciprocate between a first position
and a second position in response to a change in pressure of a
fluid within the second bore; wherein each piston of the plurality
of pistons is biased towards its first position; wherein each
piston port and each piston are disposed at a location in the
rotating sleeve that passes the sensor during each rotation when
the rotating sleeve rotates relative to the housing; wherein the
sensor is configured to detect each piston when the piston rotates
past the sensor and the piston is in its second position; and
wherein each piston includes a sensing portion that is in fluid
communication with the second bore, each sensing portion having a
wettable face area that differs from the wettable face area of
another of the plurality of pistons.
9. The device of claim 7 wherein the RSA further comprises a
rotational speed indicator coupled to the rotating sleeve at a
location that passes the sensor during each rotation when the
rotating sleeve rotates relative to the housing; and wherein the
sensor is configured to detect the rotational speed indicator when
the rotational speed indicator rotates past the sensor.
10. The device of claim 9 wherein the plurality of piston ports,
the plurality of pistons, the sensor port, the sensor, and the
rotational speed indicator are all aligned parallel to a plane that
extends perpendicular to the central axis.
11. The device of claim 7 wherein the RSA further comprises a burst
disc disposed to seal the first piston port at a location between
the second bore and the first piston.
12. The device of claim 7 further comprising a piston assembly
comprising: a piston cartridge disposed at a fixed location within
the first piston port; and the piston slidingly disposed in the
piston cartridge; wherein the piston is separated from the sleeve
by the piston cartridge.
13. The device of claim 7 wherein the first piston is configured to
be free from sliding engagement with the first piston port.
14. The device of claim 7 wherein the sensor is configured to
detect the first piston by a phenomenon selected from a group
consisting of: proximity, magnetic field, Hall Effect, contact,
induction, capacitive interaction, and photoelectric
interaction.
15. A rotating control device for a well, the device comprising: a
housing having a through-bore extending along a central axis and a
sensor positioned at a first axial position; a sleeve configured to
rotate within the through-bore of the housing; and a piston coupled
to the sleeve and configured to move from a first position to a
second position in response to a pressure change of a fluid within
the sleeve, the piston being coupled to the sleeve at a location
such that it passes by the first axial position periodically when
the sleeve rotates within the through-bore; wherein the first
piston is configured to be free from sliding engagement with the
sleeve; and wherein the sensor is configured to detect the piston
when the piston is in the second position.
16. The rotating control device of claim 15 wherein the sensor is
positioned at a discrete circumferential location about the central
axis.
17. The rotating control device of claim 15 further comprising a
piston assembly comprising: a piston cartridge disposed at a fixed
location in the sleeve; and the piston slidingly disposed in the
piston cartridge; wherein the piston is separated from the sleeve
by the piston cartridge.
18. The rotating control device of claim 15 further comprising: a
plurality of piston assemblies, each piston assembly comprising: a
piston cartridge disposed at a fixed location in the sleeve and
including a fluid communication bore, a location that passes by the
first axial position periodically when the sleeve rotates; and a
piston slidingly disposed in the piston cartridge and separated
from the sleeve by the piston cartridge, the piston including a
piston neck slidingly and sealingly received within the fluid
communication bore, the piston configured to move from a first
position to a second position in response to a pressure change of a
fluid within the sleeve; and wherein each piston neck of the
plurality of piston assemblies has a different wettable face area
than another of the piston necks.
19. The rotating control device of claim 15 further comprising a
rotational speed indicator coupled to the rotating sleeve at a
location that passes the sensor during each rotation of the sleeve
relative to the housing; wherein the sensor is configured to detect
the rotational speed indicator when the rotational speed indicator
rotates past the sensor.
20. A method for operating a rotating control device, the method
comprising: providing a housing having a through-bore extending
along a central axis, a housing wall, and a sensor disposed at a
sensor position in the housing; disposing a sleeve within the
through-bore of the housing, the sleeve configured to rotate about
the central axis and comprising a sleeve bore aligned with the
central axis ; coupling a pressure-responsive assembly to the
sleeve at a location such that the pressure-responsive element is
in fluid communication with the sleeve bore and such that the
pressure-responsive assembly passes the sensor position
periodically as the sleeve rotates , wherein the
pressure-responsive assembly that includes a pressure-responsive
element configured to be free of sliding engagement with the
sleeve; disposing a tubular string sealingly within the sleeve
bore; rotating the tubular string and the sleeve with respect to
the housing; using the sensor, detecting a response of the
pressure-responsive assembly when pressure in the sleeve bore
reaches an activation pressure; and performing a system action when
the sensor detects a response of the pressure-responsive
assembly.
21. The method of claim 20 wherein detecting a response of the
pressure-responsive assembly includes measuring periodically the
pressure in the sleeve bore.
22. The method of claim 20 wherein the pressure-responsive element
includes a detectable member coupled for movement with a piston
disposed in a cartridge; and wherein detecting a response of the
pressure-responsive assembly includes detecting radial movement of
the pressure-responsive element relative to the cartridge and the
sleeve.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of U.S. provisional
application Ser. No. 62/622,411 filed Jan. 26, 2018, and entitled
"Rotating Control Devices and Methods to Detect Pressure Within
Rotating Members," which is hereby incorporated herein by reference
in its entirety for all purposes.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
BACKGROUND
Field of the Disclosure
[0003] The present disclosure relates generally to drilling systems
and to rotating control devices for such systems. More
particularly, the disclosure relates to systems and methods for
monitoring annular seals between concentric fluid conduits as they
rotate relative to each other.
Background to the Disclosure
[0004] In applications requiring the transmission of fluid under
relatively high pressure, it is sometimes necessary to interconnect
a rotatable conduit with a stationary conduit, and to provide
annular seals therebetween to prevent leakage of the pressurized
fluid. One such application is in drilling operations where a drill
pipe or another tubular member passes through a rotating control
device (RCD), where the outer housing of the RCD remains stationary
while an internal sleeve and annular seals surround and rotate
along with the drill pipe. The annular seals allow the drill pipe
to move axially into or out from a wellbore without fluid leakage.
When it is thought that a seal failure has occurred--whether actual
or perceived--drilling operations are halted so that the seals can
be inspected and possibly replaced. However, drilling costs are
very high, such that downtime must be avoided or minimized as much
as possible. Consequently, systems and apparatus that can
definitively indicate that a seal failure is imminent or has
occurred would be welcomed by the industry.
BRIEF SUMMARY OF THE DISCLOSURE
[0005] These and other needs in the art are addressed in one
embodiment by a rotating control device (RCD) for a well
comprising: a housing having a through-bore extending along a
central axis, a housing wall, and a sensor disposed at a sensor
position in the housing and extending into the housing wall. The
RCD includes a sleeve comprising a sleeve bore aligned with the
central axis and configured to rotate about the central axis,
within the through-bore of the housing, as well as a
pressure-responsive assembly coupled to the sleeve and configured
to generate a response to a pressure of fluid within the sleeve
bore. The pressure-responsive assembly is coupled to the sleeve at
a location such that it passes the sensor position periodically as
the sleeve rotates within the through-bore. The sensor is
configured to detect the response of the pressure-responsive
assembly.
[0006] In some embodiments, the pressure-responsive assembly
includes a pressure-responsive element in fluid communication with
the sleeve bore; and the pressure-responsive element is configured
to be free of sliding engagement with the sleeve when responding to
a change in pressure in the sleeve bore.
[0007] In some embodiments, the pressure-responsive assembly
comprises a first piston slidingly disposed inside a piston
cartridge and configured to move from a first position to a second
position relative to the piston cartridge in response to an
activation pressure in the fluid within the sleeve; wherein the
sensor is configured to detect the presence of the first piston
when the first piston is in the second position and passes the
sensor position; and wherein the piston is separated from the
sleeve by the piston cartridge.
[0008] The sleeve may further include an outer surface, and a first
piston port extending from the sleeve outer surface, with the first
piston port being in fluid communication with the sleeve bore. In
some embodiments, the pressure-responsive assembly is disposed in
the first piston port with the first piston in fluid communication
with the sleeve bore; wherein the first piston is configured to
slide without contacting the first piston port.
[0009] In some embodiments, the rotating control device further
comprises a burst disc coupled to the piston cartridge and disposed
to seal the first piston from the fluid within the sleeve until the
fluid reaches or exceeds a prescribed pressure.
[0010] In some embodiments, the rotating control device further
comprises a plurality of pressure-responsive assemblies, each
pressure-responsive assembly coupled to the sleeve at a different
location such that it passes the sensor position periodically as
the sleeve rotates within the through-bore; wherein each
pressure-responsive assembly is configured to generate a response
to a particular pressure of the fluid within the sleeve bore; and
the sensor is configured to detect the responses of each of the
plurality of pressure-responsive assemblies.
[0011] In some embodiments, the pressure-responsive assembly
comprises a transducer configured to emit a first wireless signal
including pressure data corresponding to the pressure of the fluid
within the sleeve; wherein the sensor comprises a receiver and
transmitter device configured to receive the pressure data from the
transducer when the transducer is within a detection range of the
sensor, and wherein the receiver and transmitter device is
configured to transmit the pressure data beyond the housing.
[0012] Also disclosed is an RCD including: a housing comprising a
first bore extending along a central axis, and a sensor port
extending to the first bore, the sensor port disposed at a discrete
circumferential location about the central axis; a sensor disposed
within the sensor port; a rotating sleeve assembly (RSA) extending
at least partially within the first bore. The RSA includes: a
rotating sleeve configured to rotate about the central axis
relative to the housing and comprising a sleeve outer surface, a
second bore coaxially aligned with the first bore, and a first
piston port extending from the sleeve outer surface to the second
bore; and a first piston disposed within the first piston port and
configured to reciprocate between a first position and a second
position in response to a change in pressure of fluid within the
second bore. The first piston port and the first piston are
disposed at a location in the rotating sleeve that passes the
sensor periodically when the rotating sleeve rotates relative to
the housing; and the sensor is configured to detect the first
piston when the first piston rotates past the sensor and is in its
second position.
[0013] In some embodiments, the rotating sleeve further comprises a
plurality of piston ports, and the RSA comprises a plurality of
pistons, each piston being disposed within one of the plurality of
piston ports and configured to reciprocate between a first position
and a second position in response to a change in pressure of a
fluid within the second bore; wherein each piston of the plurality
of pistons is biased towards its first position and each piston
port and each piston are disposed at a location in the rotating
sleeve that passes the sensor during each rotation when the
rotating sleeve rotates relative to the housing. The sensor is
configured to detect each piston when the piston rotates past the
sensor and the piston is in its second position; and wherein each
piston includes a sensing portion that is in fluid communication
with the second bore, each sensing portion having a wettable face
area that differs from the wettable face area of another of the
plurality of pistons.
[0014] In some embodiments, the RSA further comprises a rotational
speed indicator coupled to the rotating sleeve at a location that
passes the sensor during each rotation when the rotating sleeve
rotates relative to the housing; and wherein the sensor is
configured to detect the rotational speed indicator when the
rotational speed indicator rotates past the sensor.
[0015] In some embodiments, the plurality of piston ports, the
plurality of pistons, the sensor port, the sensor, and the
rotational speed indicator are all aligned parallel to a plane that
extends perpendicular to the central axis.
[0016] In some embodiments, the RSA further comprises a burst disc
disposed to seal the first piston port at a location between the
second bore and the first piston.
[0017] In some embodiments, the RSA further includes a piston
assembly comprising: a piston cartridge disposed at a fixed
location within the first piston port; and the piston slidingly
disposed in the piston cartridge; wherein the piston is separated
from the sleeve by the piston cartridge. The first piston may be
configured to be free from sliding engagement with the first piston
port. The sensor may be one configured to detect the first piston
by a phenomenon selected from a group consisting of: proximity,
magnetic field, Hall Effect, contact, induction, capacitive
interaction, and photoelectric interaction.
[0018] Also disclosed is an RCD comprising: a housing having a
through-bore extending along a central axis and a sensor positioned
at a first axial position; a sleeve configured to rotate within the
through-bore of the housing; and a piston coupled to the sleeve and
configured to move from a first position to a second position in
response to a pressure change of a fluid within the sleeve, the
piston being coupled to the sleeve at a location such that it
passes by the first axial position periodically when the sleeve
rotates within the through-bore. The first piston is configured to
be free from sliding engagement with the sleeve, and the sensor is
configured to detect the piston when the piston is in the second
position. In some embodiments, the sensor is positioned at a
discrete circumferential location about the central axis, and in
some embodiments, the RCD includes a piston assembly comprising: a
piston cartridge disposed at a fixed location in the sleeve,
wherein the piston is slidingly disposed in the piston cartridge
and the piston is separated from the sleeve by the piston
cartridge.
[0019] In some embodiments, the RCD incudes: a plurality of piston
assemblies, each piston assembly comprising: a piston cartridge
disposed at a fixed location in the sleeve and including a fluid
communication bore, a location that passes by the first axial
position periodically when the sleeve rotates; and a piston
slidingly disposed in the piston cartridge and separated from the
sleeve by the piston cartridge, the piston including a piston neck
slidingly and sealingly received within the fluid communication
bore, the piston configured to move from a first position to a
second position in response to a pressure change of a fluid within
the sleeve; wherein each piston neck of the plurality of piston
assemblies has a different wettable face area than another of the
piston necks.
[0020] In some embodiments, the RCD further comprises a rotational
speed indicator coupled to the rotating sleeve at a location that
passes the sensor during each rotation of the sleeve relative to
the housing; wherein the sensor is configured to detect the
rotational speed indicator when the rotational speed indicator
rotates past the sensor.
[0021] A method for operating a rotating control device is
disclosed and includes: providing a housing having a through-bore,
a housing wall, and a sensor disposed at a sensor position in the
housing; disposing a sleeve within the through-bore of the housing,
the sleeve configured to rotate about the central axis of the
housing and comprising a sleeve bore aligned with that axis;
coupling a pressure-responsive assembly that includes a
pressure-responsive element to the sleeve at a location such that
the pressure-responsive assembly passes the sensor position
periodically as the sleeve rotates within the through-bore, and
such that the pressure-responsive element is in fluid communication
with the sleeve bore. The method further incudes: disposing a
tubular string sealingly within the sleeve bore; rotating the
tubular string and the sleeve with respect to the housing; and,
using the sensor, detecting a response of the pressure-responsive
assembly when pressure in the sleeve bore reaches an activation
pressure; performing a system action when the sensor detects a
response of the pressure-responsive assembly. The detecting may
include measuring periodically the pressure in the sleeve bore.
Further, where the detectable member is coupled for movement with a
piston disposed in a cartridge, the detecting may include detecting
radial movement of the pressure-responsive element relative to the
cartridge and the sleeve.
[0022] Thus, embodiments described herein include a combination of
features and characteristics intended to address various
shortcomings associated with certain prior devices, systems, and
methods. The various features and characteristics described above,
as well as others, will be readily apparent to those of ordinary
skill in the art upon reading the following detailed description,
and by referring to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] For a detailed description of the disclosed exemplary
embodiments, reference will now be made to the accompanying
drawings:
[0024] FIG. 1 shows cross-sectional side view of an embodiment of a
rotating control device having a pressure-responsive assembly
mounted in a rotating sleeve in accordance with principles
described herein;
[0025] FIG. 2 shows an enlarged, cross-sectional side view of the
rotating control device of FIG. 1;
[0026] FIG. 3 shows cross-sectional top view of the rotating sleeve
of the rotating control device of FIG. 2;
[0027] FIG. 4 shows a cross-sectional side view of the
pressure-responsive assembly of FIG. 2;
[0028] FIGS. 5A and 5B show perspective views of a cap covering the
external end of the pressure-responsive assembly in FIG. 2;
[0029] FIG. 6 shows an enlarged cross-sectional side view of the
rotating control device of FIG. 1 with the pressure-responsive
assembly in a deactivated state;
[0030] FIG. 7 shows an enlarged cross-sectional side view of the
rotating control device of FIG. 1 with the pressure-responsive
assembly in an activated state;
[0031] FIG. 8 shows another embodiment of a pressure-responsive
assembly in accordance with principles described herein;
[0032] FIG. 9 shows another embodiment of a rotating control device
having a pressure-responsive assembly mounted in a rotating sleeve
in accordance with principles described herein; and
[0033] FIG. 10 is a flow diagram showing a method for operating a
rotating control device configured for use in an oil well system in
accordance with principles described herein.
NOTATION AND NOMENCLATURE
[0034] The following description is exemplary of certain
embodiments of the disclosure. One of ordinary skill in the art
will understand that the following description has broad
application, and the discussion of any embodiment is meant to be
exemplary of that embodiment, and is not intended to suggest in any
way that the scope of the disclosure, including the claims, is
limited to that embodiment.
[0035] The figures are not drawn to-scale. Certain features and
components disclosed herein may be shown exaggerated in scale or in
somewhat schematic form, and some details of conventional elements
may not be shown in the interest of clarity and conciseness. In
some of the figures, in order to improve clarity and conciseness,
one or more components or aspects of a component may be omitted or
may not have reference numerals identifying the features or
components. In addition, within the specification, including the
drawings, like or identical reference numerals may be used to
identify common or similar elements.
[0036] As used herein, including in the claims, the terms
"including" and "comprising," as well as derivations of these, are
used in an open-ended fashion, and thus are to be interpreted to
mean "including, but not limited to . . . " Also, the term "couple"
or "couples" means either an indirect or direct connection. Thus,
if a first component couples or is coupled to a second component,
the connection between the components may be through a direct
engagement of the two components, or through an indirect connection
that is accomplished via other intermediate components, devices
and/or connections. The recitation "based on" means "based at least
in part on." Therefore, if X is based on Y, then X may be based on
Y and on any number of other factors. The word "or" is used in an
inclusive manner. For example, "A or B" means any of the following:
"A" alone, "B" alone, or both "A" and "B."
[0037] In addition, the terms "axial" and "axially" generally mean
along or parallel to a given axis, while the terms "radial" and
"radially" generally mean perpendicular to the axis. For instance,
an axial distance refers to a distance measured along or parallel
to a given axis, and a radial distance means a distance measured
perpendicular to the axis. Furthermore, any reference to a relative
direction or relative position is made for purpose of clarity, with
examples including "top," "bottom," "up," "upper," "upward,"
"down," "lower," "clockwise," "left," "leftward," "right," and
"right-hand." For example, a relative direction or a relative
position of an object or feature may pertain to the orientation as
shown in a figure or as described. If the object or feature were
viewed from another orientation or were implemented in another
orientation, it may then be helpful to describe the direction or
position using an alternate term.
DETAILED DESCRIPTION OF THE DISCLOSED EXEMPLARY EMBODIMENTS
[0038] The present disclosure involves monitoring potential fluid
leakage between a rotatable conduit and a stationary conduit that
are interconnected. Leakage between the rotatable conduit and the
stationary conduit is inhibited by seals that may rotate with the
rotatable conduit or may remain stationary with the stationary
conduit, but eventually, a seal may fail, allowing leakage.
Gathering information so as to know when a seal fails or predict
failure can be challenging. Commonly, fluid leakage is avoided by
preventative maintenance. Various embodiments disclosed herein
provide indication of fluid leakage past a seal. These embodiments
include a pressure-responsive element or assembly, for example a
pressure sensor or a movable piston, coupled to a rotating member
and arranged in fluid communication with a zone where leakage may
occur.
[0039] Referring to FIG. 1, in an exemplary embodiment, a well
system 90 includes equipment for various well operations 92,
including a rotating control device (RCD) 100, governed by a
control system 94. RCD 100 extends along a central axis 101 and is
configured to receive sealingly a tubular member, which in this
example is a pipe 102, which may be part of a string of tubular
members. Device 100 is suitable as a member of a wellhead over a
borehole of a well, such as a hydrocarbon well. Device 100 includes
an outer housing 110 holding a sensor 120 and includes a rotating
sleeve assembly (RSA) 125 received within housing 110. RSA 125
holds a pressure-responsive assembly within housing 110, generally
aligned with sensor 120 along axis 101. In this embodiment, the
pressure-responsive assembly is a piston assembly 200. Sensor 120
is configured to detect the presence of the assembly 200 as a
result of one or more pressure conditions that may exist in sleeve
assembly 125 as sleeve assembly 125 or pipe 102 causes assembly 200
to rotate relative to housing 110 and sensor 120.
[0040] Housing 110 includes a housing wall or tubular body 111
extending along the central axis 101 from a lower end 112 to an
upper end 113, having an outer surface and a through-bore 114.
Through-bore 114 is centered on axis 101 and defines an inner wall.
Housing 110 also includes a sensor port 116 extending along a
central axis 117 through tubular body 111 to the through-bore 114.
Housing 110 also includes a plurality of fluid ports 118 also
extending radially through tubular body 111 to the through-bore
114, and being axially spaced from port 116. Sensor 120 is disposed
in sensor port 116, extending toward the through-bore 114. The
axial position of port 116 and sensor 120 may be measured from any
convenient location such as a surface at the housing's upper end
113 or a surface at its lower end 112. The location of port 116 in
housing 110 defines a sensor position for sensor 120. The sensor
position may be further defined by the depth of sensor 120 within
port 116 or the proximity of the inner end of sensor 120 to the
surface of through-bore 114. Port 116 and sensor 120 are positioned
at a discrete axial location along central axis 101 and at a
discrete circumferential location about axis 101.
[0041] Rotating sleeve assembly RSA 125 extends at least partially
within the through-bore 114 of housing 110. RSA 125 includes a
rotatable sleeve 130 received within a bearing assembly 180 to
rotate about axis 101 relative to the housing 110, a speed
indicator 131 received in sleeve 130 at a location along axis 101
that is aligned with sensor 120 of outer housing 110, and piston
assembly 200 received in sleeve 130 at the same location along axis
101 as speed indicator 131. Consequently, assembly 200 is also
axially aligned with sensor 120 so it can be detected by sensor
120. Sleeve 130 and pipe 102, when installed, are configured as
rotatable conduit, and housing 110 is configured as a stationary
conduit.
[0042] Sensor 120 is configured to detect the presence of speed
indicator 131 and to detect the presence of piston assembly 200 by
any known technology, capability, or phenomenon, which may be
selected from the sensor group consisting of: proximity, magnetic
field, Hall Effect, contact, reed, induction, capacitive
interaction, and photoelectric interaction, as examples. In FIG. 1,
speed indicator 131 and piston assembly 200 each include a magnet,
and sensor 120 includes Hall Effect sensor; although, various other
embodiments include another type of speed indicator 131, piston
assembly 200, or another type of sensor 120.
[0043] Rotating sleeve 130 includes a sleeve outer surface 134 and
a bore 136 extending from a lower end 132 to an upper end 133. In
FIG. 1, rotating sleeve 130 is formed from an upper sleeve member
140 coupled to a lower sleeve member 160 by a sleeve coupling 165.
Referring to both FIG. 1 and FIG. 2, a collar 168 is coupled to
sleeve member 140 at upper end 133, and an upper packing element
170A extends downward from the bottom of collar 168, into member
140. Collar 168 is generally tubular, being open at both ends to
receive pipe 102 therethrough. A lower packing element 170B extends
downward from sleeve member 160 at lower end 132. Packing elements
170A,B are configured to seal around the circumference of pipe 102,
isolating the bore 136 from an upper portion of collar 168 and from
upper and lower portions of bore 114 in housing 110, to prevent
fluid leakage from these regions. The seal of packing elements
170A,B is maintained even as sleeve 130 and pipe 102 rotate
relative to housing 110 during operation. In at least some modes of
operation, rotation of pipe 102 causes sleeve 130 to rotate due to
the gripping action of elements 170A,B. Collar 168, packing
elements 170A,B, and bore 136 provide a sealable through-passage
for a tubular member, e.g. pipe 102, to extend or pass through
housing 110, which in some arrangements leads into a borehole. Bore
136 is configured to be an isolated chamber when a tubular member
is installed.
[0044] Upper sleeve member 140 extends from a threaded lower end
142, which attaches to sleeve coupling 165, to upper end 133, which
attaches to collar 168. Sleeve member 140 includes a radially
protruding annular shoulder 146 located between ends 142, 133, a
port 148 extending into shoulder 146 along a central axis 149
coplanar with central axis 117 of port 116, and a piston port 152
extending into shoulder 146 along the same axis 149 but opposite
port 148. Some misalignment between axis 149 and 117 is acceptable
in various embodiments depending on the sensitivity of sensor 120.
Port 148 is configured to receive speed indicator 131 at a fixed
position along port axis 149, disposing speed indicator 131 at a
fixed distance from axis 101, being generally flush or adjacent to
outer surface 134. Whenever sleeve 130 rotates the indicator 131 to
the circumferential position of sensor 120, the magnet of indicator
131 is at a fixed distance from sensor 120 within its detection
range (e.g. a prescribed distance). Repeated movement of speed
indicator 131 past sensor 120 provides a measurement of the
rotational speed of sleeve 430 with respect to housing 110. Thus,
sensor 120 is configured as a speed sensor.
[0045] A shown in FIG. 3, in the current embodiment, shoulder 146
of sleeve member 140 includes a plurality of ports 152 aligned on a
common plane with port 148. Each port 152 extends from outer
surface 134 to the bore 136 and includes first, second, and third
portions each having a different diameter and resulting in a first
shoulder 154A and a second shoulder 154B, both facing radially
outward. Shoulder 154A is proximal bore 136 and distal outer
surface 134 of sleeve 130, while shoulder 154B is proximal outer
surface 134. Each port 152 is configured to receive a piston
assembly 200 at a selected or fixed location. In FIG. 3, piston
assembly 200 threaded within port 152 and is disposed against
shoulder 154A. Thus, the current embodiment of rotating sleeve 130
includes a plurality of piston assemblies 200. In FIG. 3, rotating
sleeve 130 includes three piston ports 152 and three piston
assemblies 200. As stated above, one of the piston ports 152 is
aligned along the same central axis 149 as port 148. The other two
ports 152 are aligned and extend along a second central axis 149
coplanar with and perpendicular to the first axis 149. Piston
assemblies 200 in ports 152 and speed indicator 131 in port 148 are
aligned parallel to the cross-sectional plane shown in FIG. 3,
which extends perpendicular to the central axis 101 of device 100.
Some embodiments have other orientations for a port 152 or the
multiple ports 152.
[0046] Referring again to FIG. 1, bearing assembly 180 includes a
bearing housing 182 that is coupled within housing 110 to remain
stationary, a bearing sleeve 184 coupled to sleeve 130 to grasp and
rotate with sleeve 130, and bearing 186 coupled between housing 182
and sleeve 186. In this example, bearing 186 includes two opposing
sets of tapered roller bearings to resist axial thrust in either
vertical direction from, for example, pipe 102.
[0047] In FIG. 1, control system 94 is coupled to sensor 120 of RCD
100 by a communication conductor or cable 192. Control system 94 of
well system 95 governs the well operations 92 and monitors
responses from sensor includes RCD 100. For example, during
operation, as speed indicator 131 periodically passes sensor 120,
control system 90 determines the rotational speed of sleeve 130
with pipe 102. If a leak occurs through one of the seals 170A,
170B, and the fluid pressure in bore 136 rises to an activation
pressure (described below) for one of the piston assemblies 200,
the corresponding piston 250 and magnet 284 will move radially
outward to a second position. Sensor 120 will detect this response,
and control system 94 will perform a system action, causing a
change to a well operation 92, such as activating an indicator 194,
storing process data electronically, reducing the flow of drilling
mud, reducing drilling speed, or another action. Indicator 194 may
produce an audible or visual warning and may be a stand-alone
device or may be incorporated into a graphical user interface, as
examples. In some instances, when the pressure in bore 136 rises
further, another piston assembly 200 (e.g. FIG. 3) experiences an
activation pressure, causing the corresponding piston 250 and
magnet 284 to move radially outward to a second position. Sensor
120 will detect this additional response and may perform another
system action, such as modifying the performance of indicator 194
or performing one of the other system actions describe above.
[0048] Referring now to FIG. 4, piston assembly 200 extends along a
central axis 201 from a first end 202 to a second end 203 and
includes a piston 250 slidingly received within piston cartridge
210 and held by a piston nut 230. Piston cartridge 210 includes a
cylindrical body 212 that includes a threaded region 214 on its
outer surface proximal but spaced apart from end 203, a fluid
communication bore 216, a counter bore 218 extending from bore 216,
a threaded counter bore 219 extending from bore 218 to end 203, and
an annular face seal 222 at end 202 to engage shoulder 154A of port
152 (FIG. 3). In FIG. 3, piston cartridge 210 is threaded within
port 152 of rotatable sleeve 130 and is disposed at a fixed
location against shoulder 154A. Referring again to FIG. 4, the base
of bore 218 forms a shoulder 220 facing end 203 where bore 218
intersects with bore 216. The base of bore 219 forms a shoulder 221
facing end 203 where bore 219 intersects with bore 218. Bores 216,
218, 219 are concentric about axis 201. Piston nut 230 is received
within cartridge 210 and includes a base 232 configured to couple
threadingly to counter bore 219, a neck 234 extending from base 232
distal or opposite end 203, a through-bore 236 extending axially
through base 232 and neck 234, and a tool socket 238 formed in
through-bore 236 proximal at end 203. Base 232 is configured to
couple threadingly to counter bore 219 and butt against shoulder
221. In this configuration, bore 219 includes straight threads, but
in some embodiments bore 219 includes another type of thread, such
as tapered pipe threads.
[0049] Piston 250 extends along central axis 201 from a first end
252 to a second end 253. Piston 250 includes a base portion 254
extending from second end 253, a shoulder portion 256 extending
from base portion 254, a piston neck 258 extending from shoulder
portion 256, and a counter bore 272 extending into the outer end of
base portion 254 at second end 253, opposite neck 258. Base portion
254, shoulder portion 256, and neck 258 are each round and
concentric about axis 201. Shoulder portion 256 has a larger
diameter than base portion 254 and neck 258. Assembled as shown,
neck 258 is slidingly received within bore 216, shoulder portion
256 slidingly received within bore 218, and base portion 254
extends from bore 216 to bore 218. A clearance is provided between
circumference of shoulder portion 256 and bore 218 to allow a
fluid, such as air, that is trapped in cartridge 210 to move
axially from side to side of portion 256 as piston 250 reciprocates
during operation. An annular seal 274 is disposed about the
circumference of neck 258. A resilient member, which in this
embodiment is a spring 280, is received about piston base portion
254 and about neck 234 of nut 230. Spring is held between the nut's
base 232 and piston shoulder portion 256. The outer end of piston
250 includes a detectable portion or member, which in this example
is a magnet 284. Magnet 284 is threadingly received into the
piston's counter bore 272 and includes a shouldered end 288 that is
located outside and beyond piston 250, toward end 203. The combined
length of piston 250 and magnet 284 is shorter than the length of
cartridge 210.
[0050] Referring again to FIG. 3, the three piston assemblies 200
are threaded into piston ports 152, and a threaded cartridge cap
290 is installed within the outer end of each port 152 adjacent
shoulder 154B. Each piston assembly 200 is configured to be
assembled and then installed as a single unit into a port 152. Caps
290 prevent or discourage liquids, slurries, or contaminants in
bore 114 from contacting piston assembly 200. Cap 290 provides
piston assembly 200 with pressure compensation with respect to a
fluid in through-bore 114 of housing 110. The fluid may be, for
example, located above device 100. Cap 290 is configured to isolate
or insulate piston assembly 200 from the pressure or presence of
that fluid. FIG. 5A and FIG. 5B provide an outside and an inside
view of a cap 290. In some embodiments, cap 290 includes a material
that is non-magnetic, a polymer, or a non-metal.
[0051] FIG. 6 and FIG. 4 show a resting or deactivated state for a
piston assembly 200. FIG. 6 shows a close-view of the assembly 200
installed in sleeve 130 of device 100. Piston assembly is assembled
such that spring 280 is partially compressed between piston nut 230
and piston shoulder portion 256, which presses shoulder portion 256
radially inward toward cartridge shoulder 220. Piston neck 258 is
in fluid communication with bore 136 and performs as a sensing
portion of piston 250, making piston 250 a pressure-responsive
element. Seal 274 on neck 258 prevents fluid communication between
bore 136 and the other portions 254, 256 of piston 250. As a
result, the exposed or wettable face area of neck 258, which is
proximal the end 202, governs the response of piston 250 to fluid
pressure in bore 136. The exposed or wettable face area is the net
surface area at end 252 of piston 250 that is configured to be in
fluid communication with port 152 or bore 136 and is perpendicular
to axis 149. Thus, in some embodiments, in which piston end 252 is
no perpendicular to axis 149, whether end 252 be flat or curved,
the exposed or wettable face area is a calculable area that
projected to be perpendicular to axis 149. On piston 250, the
arrangement of neck 258 and seal 274 to engage piston cartridge 210
and not to engage port 152, configures piston assembly 200 to
respond to pressure independently of any diameter of port 152. In
addition, the inclusion of neck 258 and seal 274 configures piston
assembly 200 to respond to pressure independently of the dimensions
of structural portions of piston 250 (e.g. portions 254, 256),
structural portions that, for example, provided the mounting of
piston 250 within a housing bore (e.g. bore 218 of cartridge 210 or
port 152) or interact with spring 280.
[0052] Referring still to FIG. 6, any fluid in bore 136 is at a
pressure P1 that is too low to exert sufficient force against
piston neck 258 to overcome the force of spring 280, and thus
piston 250 remains unmoved. The piston's shoulder portion 256 is
axially spaced apart from neck 234 on nut 230. Piston neck 258 is
adjacent, and in this embodiment, is flush with end 202. Piston
magnet 284 is displaced axially inward from end 203 of piston
cartridge 210 or nut 230 and is displaced axially inward from outer
surflace 134 of sleeve 130. In this state, piston 250 and,
consequently, magnet 284 are disposed at a resting or deactivated
position with respect to housing 210 or sleeve 130, evaluated along
the aligned axes 149, 201. With magnet 284 in a deactivated
position, the radial distance 295A between magnet 284 and sensor
120 is greater than the detection range of sensor 120 when piston
axis 201 is aligned with or adjacent the sensor port axis 117, as
is the case in FIG. 6. Therefore, sensor 120 ignores magnet 284
when sleeve 130 rotates relative to housing 110.
[0053] FIG. 7 shows another close-view of the same piston assembly
200 within sleeve 130, showing an activated state for piston
assembly 200. In response to a prescribed pressure of the fluid in
bore 136, spring 280 is compressed. The fluid pressure P2 within
bore 136 in FIG. 7 is greater than pressure P1 of FIG. 6. Pressure
P2 is equal to or greater than a prescribed threshold pressure
value and may be called an "activation pressure" for the piston
assembly 200. In general, the activation pressure or a range of
activation pressures to which assembly 200 responds is be
predetermined by the configuration of assembly 200. In FIG. 7, the
increased pressure has acted against the end face of piston neck
258, causing piston 250 and magnet 284 to move to radially outward,
to an activated position with respect to piston housing 210 or
sleeve 130, evaluated along the axes 149, 201. When the fluid
pressure within sleeve 130 rises to the value P2, assembly 200
responds by piston 250 moving from a deactivated position to an
activated position. In the activated position, magnet 284 is closer
to end 203 of piston cartridge 210 or nut 230 and is closer to
outer surface 134 of sleeve 130. Shoulder portion 256 of piston 250
contacts neck 234 on nut 230, which acts as a "stop," limiting the
leftward movement of piston 250. When magnet 284 is in its
activated position, and when piston axis 201 is aligned with or is
adjacent the sensor port axis 177, as is the case in FIG. 7, then
the radial distance 295B between magnet 284 and sensor 120 is
within the detection range of sensor 120. Therefore, during
operation, sensor 120 will produce a signal in response to its
proximity to magnet 284, each time magnet 284 rotates past sensor
120. Piston 250 remains in the activated position as long as the
pressure in bore 136 remains above the prescribed pressure of the
piston assembly. Spring 280 biases piston 250 toward the innermost
deactivated position and causes piston to move to this or to an
intermediate deactivated position when pressure in bore 136 drops
below the prescribed pressure. Thus, piston 250 and magnet 284 are
configured to reciprocate within cartridge 210 between a
deactivated position and an activated position in response to fluid
pressure within bore 136 of sleeve 130. For example, the fluid
pressure may rise from rising from a value of P1 to a value of P2
and cause the piston to move. Piston assembly 200 is configured
such that piston 250, including seal 274, does not engage slidingly
the piston port 152 when responding to a change in pressure in the
sleeve bore 136. Piston 250 is separated from sleeve 130 by piston
cartridge 210. In the embodiment of FIG. 6 and FIG. 7, piston 250
does not contact piston port 152 in any position of piston 250.
[0054] The movement of piston 250 between a deactivated position
and an activated position is based on the wettable face area of
piston neck 258, the "spring constant" of spring 280, any
preloading on spring 280, the pressure inside bore 136, and, in
some embodiments, the pressure in the through-bore 114 of housing
110 at piston port 152. In some embodiments or some instances, an
intermediate activation pressure that is greater than pressure P1
but less than pressure P2 moves magnet 284 an intermediate position
that is within the detection range of sensor 120 without piston 250
moving fully to its radially outermost position, not sufficiently
displaced to contact neck 234 on nut 230. This type of intermediate
position qualifies as another activated. Similarly, it is possible
for piston 250 to be disposed away from the innermost deactivated
position that is shown in FIG. 6 and still have magnet 284 outside
detection range of sensor 120 when piston axis 201 is adjacent or
aligned with port axis 117. Any such intermediate position of
piston 250 relative to sleeve 130 may also be called a deactivated
position, wherein magnet 284 is undetectable by sensor 120.
[0055] In at least some embodiments, sensor 120 is selected to
produce an output signal having a strength or a value that varies
based on the distance between sensor 120 and piston 250, e.g.
magnet 284, when piston axis 201 is adjacent or aligned with port
axis 117 and magnet 284 is in one of a plurality of activated
positions. Sensor 120 may be an inductive-type proximity sensor,
for example. When piston 250 is moved along axis 201 to an
intermediate activated position within the detection range of
sensor 120 (as explained above), the strength or value of the
signal produced by sensor 120 may be less than a maximum strength
or value that occurs when piston 250 is in its outermost activated
position. In some embodiments, this variation in the output signal
of sensor 120 is correlated to pressure values, configuring control
device 100 to provide pressure indication or measurement over a
range of pressure values rather than just a binary "yes/no"
comparison between pressure inside sleeve 130 and a single
prescribed pressure value.
[0056] Referring again to FIG. 3, the three piston assemblies 200
are additionally labeled with the reference numerals 200A,B,C to
distinguish the different diameters and wettable face areas of the
necks 258 of each corresponding piston 250A,B,C. Each piston
250A,B,C is shown in its innermost, deactivated position unmoved by
the pressure of a fluid that may be in bore 136 when device is
unused or is operating. Piston 250A has a neck with the largest
diameter of the three pistons, piston 250B has a neck with a
smaller diameter, and piston 250C has a neck with a still smaller
diameter. In this embodiment, each spring 280 has the same spring
constant, a property that correlates the force that will be exerted
by a spring to the distance the spring is compressed or stretched,
having the units of force per unit length of displacement. The
force that a fluid in bore 136 exerts on any of the pistons is
proportional to the wettable face area of the piston's neck 258.
Each piston 250A,B,C "sees" or experiences the same fluid pressure
from bore 136. However, that fluid pressure exerts a larger force
on piston 250A than on either of the other two pistons because the
neck 258 of piston 250A has the largest wettable face area exposed
to the fluid in bore 136. Similarly, the fluid force exerted on
piston 250B is larger than the fluid force exerted on piston 250C,
which has the smallest wettable face area exposed to the fluid.
Thus, during operation of device 100 (FIG. 1), piston 250A will be
moved out of a deactivated position and to an activated position by
a lower pressure than is required to move piston 250B or piston
250C. Likewise, piston 250B will be moved out of a deactivated
position by a lower pressure than is required to move piston
250C.
[0057] Referring to FIG. 1 and FIG. 3, an operating condition will
be considered in which piston assemblies 200A,B,C become
sequentially activated and detected by sensor 120. Four pressures
will be discussed, wherein a pressure P1<a pressure P2<a
pressure P3<a pressure P4. With packing elements 170A,B
initially sealed around pipe 102, each piston 250A,B,C is in a
deactivated position and is not activated by pressure P1 that
exists in bore 136 of sleeve 130. Pipe 102 and sleeve 130, along
with packing elements 170A,B, are rotating. Initially, sensor 120
senses only speed indicator 131, which it senses once per
revolution. In this example, as the pipe 102 rotates, packing
element 170B wears, and fluid, which may be drilling mud for
example, begins to leak from the lower portion of through-bore 114
in housing 110, past packing elements 170B, and into bore 136 of
sleeve 130. As fluid enters sleeve 130, bore 136 reaches an
activation pressure P2 that is able to push piston 250A, which is
the piston with the largest neck 258, to an activated position
(e.g. FIG. 7). Sensor 120 now senses both speed indicator 131 and
the magnet 284 on piston 250A as each of these elements
periodically move past sensor 120 while sleeve 130 rotates. In at
least one embodiment, sensor 120 cannot distinguish between speed
indicator 131 and a magnet 284, rather the operator or control
system 94 (FIG. 1) detects a distinct increase in the detection
rate of sensor 120 (e.g., twice as many pulses per second) and
attributes this change to piston assembly 200A being activated by a
pressure P2 or greater but less that pressure P3. Thus, based on
the characteristics of sensor 120 and the arrangements of position
indicator 131 and piston assemblies 200 relative to sensor 120,
sensor 120 is configured to detect data for two separate
operational conditions, the first condition being rotational speed
and the second condition being elevated pressure within rotatable
sleeve 130. In some embodiments, the rotational speed of the pipe
is also measured elsewhere in the well operation system, such as in
a top drive or in a kelly table, and the data from sensor 120 is
compared against this other measurement of rotational speed to
assess whether sensor 120 is detecting speed indicator 131 alone or
it is also detecting a magnet 284 in a piston assembly 200. Thus, a
real change in rotational speed can be differentiated from a
pressure rise within sleeve 130 when evaluating the data of sensor
120.
[0058] As the scenario continues, the pressure of fluid in bore 136
increases to an activation pressure P3 that that is able to push
piston 250B to an activated position (e.g. FIG. 7). Piston 250A
remains in its activated position. Sensor 120 now senses speed
indicator 131 and two magnets 284 as these three move past sensor
120 in sequence while sleeve 130 rotates. Again, the operator or
the control system 94 interprets the additional data from sensor
120 as resulting from pressure P3 or greater being detected in bore
136, the pressure being less than P4. As fluid continues to push
past packing element 170B into bore 136, the pressure in bore 136
increases to an activation pressure P4 that that is able to push
piston 250C, which is the piston with the smallest neck 258, to an
activated position (e.g. FIG. 7). Pistons 250A,B remains in their
activated positions. Sensor 120 now senses speed indicator 131 and
three magnets 284 while sleeve 130 rotates. The operator or the
control system 94 interprets the additional data from sensor 120 as
resulting from a pressure P4 or greater being detected in bore
136.
[0059] Referring to FIG. 8, another embodiment of a
pressure-responsive assembly consistent with the present disclosure
and configured for installation in rotating control device (RCD)
100 is a piston assembly 300. An assembly 300 may replace a piston
assembly 200 in various embodiments of RCD 100 and sleeve 130.
Assembly 300 is shown installed in a piston port 152 of a rotating
sleeve 130 with port 152 extending along a central axis 149 from a
sleeve outer surface 134 and to bore 136, which extends about a
central axis 101. Sleeve 130 includes the features disclosed above,
including the figures. Assembly 300 is configured to be assembled
into a single, cohesive unit before being installed into port
152.
[0060] Assembly 300 is similar to piston assembly 200 in that
assembly 300 includes a piston 350 held within piston cartridge 310
by a piston nut 330. However, piston assembly 300 also includes an
end cap 360 that is configured to isolate piston 350 from a fluid
in bore 136 until a prescribed pressure is reached in bore 136.
Assembly 300 extends along a central axis 301 from a first end 302
to a second end 303. Piston cartridge 310 includes a cylindrical
body 312 includes an internally threaded first bore 316 extending
from end 302 and a counter bore 218 extending from end 303 to bore
316. The base of bore 218 forms a shoulder 220 facing end 203 where
bore 218 intersects with bore 216. Cartridge 310 is threadingly
received in port 152 of rotatable sleeve 130 and is disposed at a
fixed location against shoulder 154A. Piston nut 330 is externally
threaded and includes a through-bore 236 for piston 350 and a tool
socket 238 formed concentric or within bore 236. Nut 330 lacks a
neck like neck 234 on nut 220 (FIG. 4). However, even some
embodiments of nut 220 lack a neck 234.
[0061] Piston 350 extends along central axis 201 from a first end
352 to a second end 353. Piston 350 includes a base portion 354
extending from second end 353, a shoulder portion 356 extending
from portion 354 to the outer surface of first end 352, and a
counter bore 272 within portion 354 at second end 353. Shoulder
portion 356 has a larger diameter than base portion 354 and
includes a groove to receive a seal 374. A resilient member, a
spring 280, is received about piston base portion 254 and is held
between nut 330 and piston shoulder portion 356. The outer end of
piston 350 includes a detectable portion or member, which in this
example is a magnet 284 threadingly received into the piston's
counter bore 272. Spring 280 biases piston 350 and therefore magnet
284 away from assembly end 303 and toward a deactivated position of
piston 350 and magnet 284 in cartridge 310, which is the position
shown in FIG. 8. Some embodiments include a cartridge cap (FIG. 5B)
installed in the outer end of piston port 152, adjacent surface
134. In some embodiments, nut 330 exerts a preloading compression
to spring 280 while piston 350 is in its resting position.
[0062] End cap 360 includes a bore 361 extending along axis 201
from a first end 362 to a second end 363 and includes an outwardly
extending annular flange 364, and a burst or rupture disc 366. Disc
366 sealingly covers bore 361 at first end 362. Flange 364 has a
face seal 222 that engages shoulder 154A of port 152 proximal bore
136 and distal the outer surface 134 of sleeve 130. The cap's
second end 363 is threadingly received within bore 316 of cartridge
310 and flange 364. Rupture disc 366 is in fluid communication with
sleeve bore 136 and is configured to break when it experiences a
prescribed pressure differential that may be caused by a fluid
within sleeve bore 136 reaching or exceeding an activation or
threshold pressure, as discussed above. Rupture disc 366 is an
example of a pressure-responsive element that is configured not to
engage slidingly the piston port 152 when responding to a change in
pressure in the sleeve bore 136.
[0063] As assembled, shoulder portion 356 at piston end 353 is
pressed against cartridge shoulder 220 or cap 360 when piston 350
is disposed at a deactivated position as shown in FIG. 8. Piston
350, which is a pressure-responsive element, and at least a portion
of the outer surface of shoulder portion 356 will be in fluid
communication with port 152 and bore 136 if rupture disc 366
breaks. Shoulder portion 356 is a sensing portion of piston 350. If
rupture disc 366 breaks due to an activation pressure, piston 350
and magnet 284 will move outward to a second location, and this
second location will be within the sensing range of sensor 120 when
assembly 300 is rotationally aligned with sensor 120. Piston 350
will return to a deactivated position under the influence of spring
280 when the pressure subsides. Piston assembly 300 is configured
such that piston 230, including seal 374, does not engage slidingly
the piston port 152 when installed in sleeve 130 and responding to
a change in pressure in the sleeve bore 136. Piston 350 is
separated from sleeve 130 by piston cartridge 310. In the
embodiment of FIG. 8, piston 350 does not contact piston port 152
in any position of piston 350.
[0064] Piston assembly 300 is configured to operate like assembly
200 except for the addition of rupture disc 366, which governs at
least an initial the response of piston 350 to a change in pressure
within bore 136. This differs from assembly 200 in which the wetted
area of neck 258 governs the response of piston 250. To configure
assembly 300 to respond to a higher or lower pressure within bore
136, a rupture disc 366 having an appropriate pressure rating is
selected and installed. The pressure rating of disc 366 can be
varied while maintaining a constant, selected diameter for disc 366
and while maintaining a constant, selected diameter for port 152
into which disc 366 is installed. Thus, inclusion of disc 366
configures piston assembly 300 to respond to an activation pressure
independently of any diameter of port 152. The inclusion of disc
366, which initially isolates piston 350 from fluid in bore 136,
configures piston assembly 300 to respond to an activation pressure
independently of piston 350. Thus, this response of piston assembly
300 to pressure within sleeve 130 is independent of the dimensions
of structural portions of piston 350 (e.g. the diameter of a
portion 354, 356), structural portions that, for example, provide
the mounting of piston 350 within a housing bore (e.g. bore 218 of
cartridge 310) or that interact with spring 280.
[0065] To use multiple piston assemblies 300 in the configuration
of FIG. 3 and to have each assembly respond do a different pressure
or pressure change, each assembly 300 is provided with a rupture
disc 366 having an appropriate pressure rating that differs from
the other assemblies 300. In at least some of these embodiments,
all springs 280 have the same spring constant. Some embodiments
include a rupture disc 366 having a pressure rating of selected
from the group of pressure values consisting of: 200; 500; 1,000;
1,500; and 2,000 pounds per square inch (psi), as examples. Some
embodiments include a rupture disc 366 having a pressure rating
outside this group of pressure values, within suitable engineering
limits, while some other embodiments include a rupture disc 366
having a pressure rating that lies between two of the values listed
above, for example, a value of 1,255 psi.
[0066] During operation, assembly 300 remains unchanged while a
normal operating pressure P1 exists within bore 136. Exposed to
pressure P1, disc 366 remains intact, and piston 350 remains in a
deactivated position, as shown in FIG. 8. If the pressure of a
fluid in bore 136 rises to a selected activation pressure P2 of
disc 366, as may occur due to a fluid leak passing through a
packing element 170A,B, then disc 366 will rupture. After disc 366
ruptures, fluid pressure from bore 136 exerts a force on the
wettable face area of shoulder portion 356, causing piston 350 and
magnet 284 to respond by moving outward to an activated position in
which magnet 284 is located within the sensing range of sensor
120.
[0067] In at least some embodiments, by selecting an appropriate
combination of pressure rating for rupture disc 366, spring
constant for spring 280, and wettable face area of shoulder portion
356, piston assembly 300 is configured for piston 350 to move
promptly between two discrete locations (e.g. a deactivated
position and a fully activated position) without stopping or
without pausing at an intermediate position. This configuration can
be achieved, for example, by choosing a spring with a sufficiently
low spring constant as compared to the pressure rating of the burst
disc 366. For example, piston assembly 300 can be configured such
that the pressure that can burst the disc 366 can easily overcome
the resistance of the selected spring 280. In an example, the two
discrete locations are the innermost deactivated position shown in
FIG. 8 and an outermost activated position of piston 350 (similar
to FIG. 7). For at least some embodiments, when assembly 300 is
configured for discrete positioning of piston 350 and magnet 284,
the signal from sensor 120 is cleaner, providing a binary response
as pressure rises from P1 to P2, whether slowly or quickly, because
magnet 284 is either positioned outside the range of sensor 120 or
within the range of sensor 120.
[0068] Without regard to the pressure rating of a burst disc 366,
the wettable face area of shoulder portion 356 of piston 350 is
initially equal to the cross-section area of bore 361 of end cap
360. The force exerted on piston 350 is proportional to
cross-section area of bore 361 multiplied by the fluid pressure of
a fluid acting on portion 356. If this force is sufficient to
overcome spring 280 and cause piston 350 to move, then the entire
end face of portions 356 will become wetted. This increase in
wetted area results in the same pressure exerting a larger force on
piston 350, causing piston 350 to move faster or further in
opposition to spring 280. This property of piston assembly 300 may
also be used to configure for piston 350 to move promptly between
two discrete locations (e.g. the innermost, deactivated position
and a fully activated position) without stopping or without pausing
at an intermediate position) and may result in a more-defined
response from sensor 120.
[0069] Referring to FIG. 9, in an exemplary embodiment, a rotating
control device (RCD) 400 extends along a central axis 401 and is
configured to receive sealingly a tubular member along axis 401.
FIG. 9 shows a close view of the upper portion of RCD 400. Device
400 is suitable as a member of a wellhead over a borehole of a
well, such as a hydrocarbon well, and may be used in place of
device 100 or in addition to device 100. Device 400 includes an
outer housing 410 holding a sensor 420 at a selected position along
axis 401 and includes a rotating sleeve assembly (RSA) 425 received
within housing 410. RSA 425 holds a pressure-responsive assembly
within the detection range of sensor 420, at least during a portion
of the rotation cycle of RSA 425. In this embodiment, the
pressure-responsive assembly is a transducer 490 that senses
pressure and wirelessly transmits an electrical signal that is
representative of the sensed pressure. Transducer 490, which
includes an internally disposed pressure-responsive element, is
configured to measure a property of a fluid within RSA 425
periodically or steadily and to produce wireless communication
response corresponding to the measured values. Transducer 490 is
selected from a group consisting of: a pressure sensor, a
temperature sensor, a flow meter, a viscometer, and a pH meter, as
examples. In FIG. 9, transducer 490 includes a pressure sensor
configured to measure pressure over a range of possible pressures
in bore 136 and to transmit a periodic or steady wireless response
including pressure data. Sensor 420 is configured as a transceiver
to receive the wireless response including data from transducer 490
and to generate a second response based on that response from
transducer 490. Sensor 420 is configured to transmit the second
response by wire or wirelessly to a controller or another device
configured to display, store, evaluate, distribute, or otherwise
utilize the data from transducer 490. In at least some embodiments,
sensor 420 is also configured to exchange (send or receive) other
information with transducer 490. This "other information" may
include, as examples, any of the following: calibration
information, diagnostic information, a power on/off signal, and a
sleep/wake signal.
[0070] Housing 410 is similar to housing 110 of device 100
described in reference to FIG. 1. For example, continuing to
reference FIG. 9, housing 410 includes a housing wall or tubular
body 111 extending along the central axis 401, having a
through-bore 114. Through-bore 114 is centered on axis 401 and
defines an inner wall. Housing 410 includes a sensor port 116
extending through tubular body 111 to the through-bore 114. A
sensor 120, as previously described, is disposed in sensor port
116, extending toward the through-bore 114. In addition, housing
410 includes a port 416 to receive the sensor 420. Port 416 extends
through tubular body 111 to the through-bore 114. Sensor 420
extends from an inner end 422 adjacent the through-bore 114 to an
outer end 423 adjacent the outer surface of housing 410. In FIG. 9,
port 416 extends radially with respect to axis 401 and is axially
spaced apart from port 116.
[0071] Rotating sleeve assembly (RSA) 425 is similar to RSA 145 of
device 100. For example, RSA 425 extends at least partially within
the through-bore 114 of housing 410 and includes a rotatable sleeve
430, configured to rotate about central axis 401 relative to the
housing 410. Sleeve 430 is received within a bearing assembly 180,
as described above, to rotate about axis 401. RSA 425 also includes
a speed indicator 131, which includes a magnet in this example,
received in sleeve 430 at a location along axis 401 that is aligned
with sensor 120 in outer housing 410. In addition, sleeve assembly
425 includes a transducer 490 received in sleeve 430 at a location
along axis 401 that allows transducer 490 to communicate with
sensor 420 during at least a portion of a revolution of sleeve
430.
[0072] Like sleeve 130, rotatable sleeve 430 includes a sleeve
outer surface 134 and a bore 136 extending along central axis 401
with packing elements coupled adjacent each end of sleeve 430. In
FIG. 9, rotating sleeve 430 is formed from multiple members
coupled. An upper packing element 170A is shown extending downward
from the bottom of an upper collar 168, into member 140. Collar
168, the packing elements, and bore 136 provide a sealable
through-passage for a tubular member, to extend into or pass
through the housing 410, which in some arrangements leads into a
borehole. Bore 136 is configured to be an isolated chamber when a
tubular member is installed.
[0073] Like sleeve 130, sleeve 430 includes a radially protruding
annular shoulder 146 and a port 148 extending into shoulder 146.
Port 148 is aligned with sensor port 116 along axis 401. Port 148
is configured to receive speed indicator 131 at a fixed radial
distance from axis 401 and being generally flush or adjacent to
outer surface 134. Whenever sleeve 430 rotates the indicator 131 to
the circumferential position of speed sensor 120, the magnet of
indicator 131 is at a fixed distance from speed sensor 120 within
its detection range (e.g. a prescribed distance).
[0074] Sleeve 430 also includes a sensor port 452 extending from an
outer port-end 453 at the bottom of shoulder 146 to an inner
port-end 454 that intersects bore 136. In FIG. 9, port 453 includes
a 90.degree. turn. A first end 492 of transducer 490 is located
within port 452. A second end 493 of transducer 490 is located
outside and adjacent the outer port-end 453, extending below
shoulder 146. Transducer 490, including its pressure-responsive
element, is in fluid communication with bore 136. As shown, a first
portion of port 452 and wireless transducer 490 extend parallel to
axis 401 for greater clearance of second end 493, meaning the
exposed length of end 493 is not limited by the radial distance
between shoulder 146 and the adjacent portion of housing 410. The
exposed second end 493 of transducer 490 is disposed at a location
that gives transducer 490 a wireless communication path to the
inner end 422 of sensor 420. For example, in FIG. 9, the exposed
second end 493 of transducer 490 is disposed along axis 401
adjacent the axial location of inner end 422 of sensor 420, placing
transducer 490 in the "line-of-sight" of sensor 420 during at least
a portion of the revolution of sleeve 430. During at least a
portion of the revolution of sleeve 430, transducer 490
communicates wirelessly with sensor 420 to provide data related to
a property of a fluid that is in bore 136, which in this example is
pressure.
[0075] FIG. 10 shows a method 500 for operating a rotating control
device configured for use in an oil well system. Method 500 is
applicable for operating an RCD 100, 400, as examples. At block
502, method 500 includes providing a housing having a through-bore
extending along a central axis, a housing wall, and a sensor
disposed at a sensor position in the housing and extending into the
housing wall. Block 504 includes disposing a sleeve within the
through-bore of the housing, the sleeve comprising a sleeve bore
aligned with the central axis and configured to rotate about the
central axis. Block 506 includes providing a pressure-responsive
assembly that includes a pressure-responsive element configured to
be free of sliding engagement with the sleeve. Block 508 includes
coupling a pressure-responsive assembly to the sleeve at a location
such that the pressure-responsive assembly passes the sensor
position periodically as the sleeve rotates within the through-bore
and such that the pressure-responsive element is in fluid
communication with the sleeve bore. Block 510 includes disposing a
tubular string sealingly within the sleeve bore.
[0076] Block 512 includes rotating the tubular string and the
sleeve with respect to the housing, as may be accomplished by a
rotary table, for example. Block 514 includes operating the sensor
to detect a response of the pressure-responsive assembly when
pressure in the sleeve bore reaches an activation pressure. Block
516 includes performing a system action when the sensor detects a
response of the pressure-responsive assembly. Various embodiments
of method 500 may include fewer operations than described, and
other embodiments of method 500 include additional operations.
[0077] Although various embodiments disclosed herein included
multiple pistons 250, 350 with each piston coupled to and
potentially driven by a spring 280 having a same spring constant as
the other springs 280, in some embodiments, a spring coupled to a
piston has a different spring constant than does another spring
that is coupled to a different one of the multiple pistons. In some
embodiments, a first piston is coupled to a spring having a first
spring constant, and a second piston is coupled to a spring having
a different spring constant, and both pistons have the same neck
area or end area exposed to fluid in sleeve bore 136. The first and
second pistons respond to different activation pressures on account
of the different springs rather than differences in area exposed to
bore 136.
[0078] In place of magnet 284, some embodiments include another
type of detectable portion or element on a piston 250, 350,
corresponding to the sensing capability of sensor 120, as discussed
above.
[0079] Referring again to FIG. 9, in some embodiments, sensor 420
is also configured to display, store, evaluate, or otherwise
utilize the data from transducer 490 in addition to distributing a
response. In some embodiments, transducer 490 is a pressure switch,
configured to respond to a prescribed value of pressure in bore 136
similar to the response of a piston assembly 200, 300. Some
embodiments include multiple transducers 490 installed in a
rotating sleeve 430.
[0080] While exemplary embodiments have been shown and described,
modifications thereof can be made by one of ordinary skill in the
art without departing from the scope or teachings herein. The
embodiments described herein are exemplary only and are not
limiting. Many variations, combinations, and modifications of the
systems, apparatuses, and processes described herein are possible
and are within the scope of the disclosure. Accordingly, the scope
of protection is not limited to the embodiments described herein,
but is only limited by the claims that follow, the scope of which
shall include all equivalents of the subject matter of the claims.
The inclusion of any particular method step or operation within the
written description or a figure does not necessarily mean that the
particular step or operation is necessary to the method. The steps
or operations of a method listed in the specification or the claims
may be performed in any feasible order, except for those particular
steps or operations, if any, for which a sequence is expressly
stated. In some implementations two or more of the method steps or
operations may be performed in parallel, rather than serially.
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