U.S. patent application number 15/359836 was filed with the patent office on 2017-05-25 for system and methodology for establishing a fatigue life of a subsea landing string.
The applicant listed for this patent is Schlumberger Technology Corporation. Invention is credited to Laurent Alteirac, Rachel Deghuee.
Application Number | 20170145810 15/359836 |
Document ID | / |
Family ID | 58720627 |
Filed Date | 2017-05-25 |
United States Patent
Application |
20170145810 |
Kind Code |
A1 |
Deghuee; Rachel ; et
al. |
May 25, 2017 |
SYSTEM AND METHODOLOGY FOR ESTABLISHING A FATIGUE LIFE OF A SUBSEA
LANDING STRING
Abstract
A technique facilitates monitoring of a location susceptible to
fatigue due to loading experienced along a subsea landing string or
other subsea tubing string. Initially a location or locations
susceptible to fatigue may be determined along the subsea tubing
string. At least one sensor, e.g. a strain sensor, is placed along
the tubing string proximate the location susceptible to fatigue.
The strain sensor or sensors can then be used to collect data
regarding loading incurred at the location. The loading data can
then be used to determine fatigue at the location and/or at a
device proximate the location.
Inventors: |
Deghuee; Rachel; (Pearland,
TX) ; Alteirac; Laurent; (Missouri City, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Schlumberger Technology Corporation |
Sugar Land |
TX |
US |
|
|
Family ID: |
58720627 |
Appl. No.: |
15/359836 |
Filed: |
November 23, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62258875 |
Nov 23, 2015 |
|
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|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B 33/064 20130101;
E21B 17/01 20130101; E21B 47/007 20200501; E21B 33/035
20130101 |
International
Class: |
E21B 47/00 20060101
E21B047/00; E21B 33/064 20060101 E21B033/064; E21B 17/01 20060101
E21B017/01 |
Claims
1. A system for use in a well application, comprising: a blowout
preventer disposed along a seafloor; a subsea landing string
extending into the blowout preventer, the subsea landing string
comprising a plurality of landing string devices coupled by tubular
members; a plurality of sensors mounted on at least one of the
tubular members, the sensors being operated to monitor stress
loading at one or more specific locations along the subsea landing
string; and a data recorder positioned to receive data from the
plurality of sensors, the data providing an indicator of component
fatigue at one or more locations.
2. The system as recited in claim 1, wherein the plurality of
sensors comprises a strain gauge.
3. The system as recited in claim 1, wherein the plurality of
sensors comprises an accelerometer.
4. The system as recited in claim 1, wherein the plurality of
sensors comprises a strain gauge and an accelerometer.
5. The system as recited in claim 1, wherein the plurality of
landing string devices comprises a retainer valve, the plurality of
sensors being coupled to at least one tubular member connected to
the retainer valve.
6. The system as recited in claim 1, wherein the plurality of
landing string devices comprises a subsea test tree, the plurality
of sensors being coupled to at least one tubular member connected
to the subsea test tree.
7. The system as recited in claim 1, further comprising a sensor
mounted on a quick connect.
8. The system as recited in claim 1, further comprising a telemetry
system for transmitting sensor data from the plurality of sensors
to a surface location.
9. The system as recited in claim 8, further comprising a surface
processing system for receiving the sensor data, processing the
sensor data, and outputting an estimate of fatigue life with
respect to at least one of the landing string devices.
10. A method, comprising: determining a location susceptible to
fatigue along a subsea landing string; locating at least one sensor
proximate the location susceptible to fatigue; deploying the subsea
landing string into cooperation with a subsea blowout preventer;
recording data from the at least one sensor; and determining a
fatigue life estimate of a component of the subsea landing string
based on the data.
11. The method as recited in claim 10, wherein determining
comprises determining location susceptible to fatigue based on
tensile loading and wave loading.
12. The method as recited in claim 10, wherein locating the at
least one sensor comprises locating a plurality of sensors on
tubular sections of the subsea landing string.
13. The method as recited in claim 10, wherein locating the at
least one sensor comprises locating the sensor along a tubular
section of the subsea landing string connected with a landing
string device.
14. The method as recited in claim 10, wherein locating the at
least one sensor comprises locating the sensor along a tubular
section of the subsea landing string connected with a retaining
valve.
15. The method as recited in claim 10, wherein locating the at
least one sensor comprises affixing the at least one sensor
directly to a subsea landing string device.
16. The method as recited in claim 10, further comprising
transmitting the data to the surface in real time.
17. The method as recited in claim 10, wherein locating comprises
locating a strain sensor along a tubular element of the subsea
landing string.
18. A method, comprising: determining a location susceptible to
fatigue along a subsea tubing string; placing a plurality of strain
sensors proximate the location; using the plurality of strain
sensors to collect data regarding loading at the location; and
monitoring fatigue of a tubing string device by maintaining a log
of the data collected.
19. The method as recited in claim 18, wherein placing comprises
placing the plurality of sensors along tubular elements coupled to
a landing string component of the subsea tubing string; and wherein
monitoring comprises processing the data collected to determine an
estimated fatigue life of the landing string component.
20. The method as recited in claim 18, further comprising using a
telemetry system to transmit the data to the surface.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Patent Application No. 62/258,875, filed Nov. 23, 2015, of which is
herein incorporated by reference in its entirety.
BACKGROUND
[0002] In subsea hydrocarbon well applications, various equipment
is provided at the seabed. The subsea equipment may comprise a
blowout preventer (BOP) and other equipment positioned proximate
the seabed and above a wellbore extending into a subsea geologic
formation. Surface equipment, e.g. a rig, may be located at a
surface of the sea generally above the wellbore and various tubing
strings may extend between the surface equipment and the subsea
equipment. Depending on the application, the tubing string may
comprise a riser and/or subsea landing string deployed from the
surface equipment and down into cooperation with the BOP. In many
of these applications, the tubing string is subjected to periodic
loading due to wave action or other loads which occur during subsea
operations. For example, a riser may be affected by stresses
resulting from movement of the rig and from vortex induced
vibrations which occur as ocean current flows past the tubing
string and undergoes vortex shedding. Subsea landing strings may be
protected from the vortex induced vibrations because of their
relatively shorter length and protection by the BOP, but the subsea
landing strings also experience load stresses due to movement of
the rig and/or other operational effects. The fatigue resulting
from the loading can shorten the lifetime of devices along the
tubing string and of the overall tubing string.
SUMMARY
[0003] In general, a system and methodology are provided for
monitoring a location susceptible to fatigue due to loading
experienced along a subsea landing string or other subsea tubing
string. Initially a location or locations susceptible to fatigue
may be determined along the subsea tubing string. At least one
sensor, e.g. a strain sensor, is placed along the tubing string
proximate the location susceptible to fatigue. The strain sensor or
sensors can then be used to collect data regarding loading incurred
at the location. The loading data may then be used to determine
fatigue at the location and/or at a device proximate the
location.
[0004] However, many modifications are possible without materially
departing from the teachings of this disclosure. Accordingly, such
modifications are intended to be included within the scope of this
disclosure as defined in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] Certain embodiments of the disclosure will hereafter be
described with reference to the accompanying drawings, wherein like
reference numerals denote like elements. It should be understood,
however, that the accompanying figures illustrate the various
implementations described herein and are not meant to limit the
scope of various technologies described herein, and:
[0006] FIG. 1 is a schematic illustration of an example of a subsea
well system comprising subsea equipment coupled with surface
equipment by a tubing string, according to an embodiment of the
disclosure;
[0007] FIG. 2 is a schematic illustration of an example of a subsea
landing string disposed in a blowout preventer combined with
sensors for monitoring loading effects, according to an embodiment
of the disclosure;
[0008] FIG. 3 is a schematic illustration similar to that of FIG. 2
but showing examples of loads experienced at locations along the
subsea landing string, according to an embodiment of the
disclosure;
[0009] FIG. 4 is a cross-sectional view of a section of tubing
string having a plurality of strain gauges mounted to the tubing
string, according to an embodiment of the disclosure;
[0010] FIG. 5 is a schematic illustration of another example of a
subsea landing string disposed in a blowout preventer combined with
sensors for monitoring loading effects, according to an embodiment
of the disclosure;
[0011] FIG. 6 is a schematic illustration of a location being
monitored for loading effects, according to an embodiment of the
disclosure;
[0012] FIG. 7 is a schematic illustration of another example of a
subsea landing string combined with subsea a data recorder,
according to an embodiment of the disclosure;
[0013] FIG. 8 is a schematic illustration of an example of a sensor
mounted on a tubing string and combined with a telemetry system,
according to an embodiment of the disclosure;
[0014] FIG. 9 is a schematic illustration of an example of a well
system with sensors mounted on a tubing string combined with a
wireless telemetry system for relaying loading data to a surface
processing system for fatigue analysis, according to an embodiment
of the disclosure; and
[0015] FIG. 10 is a schematic illustration of an example of a
display used to display results of the fatigue analysis and
estimates of remaining life of a subsea landing string device or
other component, according to an embodiment of the disclosure.
DETAILED DESCRIPTION
[0016] In the following description, numerous details are set forth
to provide an understanding of some embodiments of the present
disclosure. However, it will be understood by those of ordinary
skill in the art that the system and/or methodology may be
practiced without these details and that numerous variations or
modifications from the described embodiments may be possible.
[0017] The present disclosure generally relates to a system and
methodology for monitoring a location or locations susceptible to
fatigue due to loading experienced along a subsea landing string or
other subsea tubing string. Initially the location(s) susceptible
to fatigue may be determined along the subsea tubing string. At
least one sensor, e.g. strain sensor, is placed along the tubing
string proximate the location susceptible to fatigue. The strain
sensor or sensors can then be used to collect data regarding
loading incurred at the location. The collected data may be
processed and evaluated to determine fatigue at the location and/or
at a device proximate the location. In some applications, for
example, strain data obtained along a tubular member may be used to
determine detrimental effects on an adjacent tubing string device.
As described in greater detail below, the strain data may be used
to predict a fatigue lifetime of a component, e.g. a device,
disposed along the subsea landing string or other tubing
string.
[0018] The system and methodology described herein may be used for
fatigue monitoring in a subsea landing string deployed into a
blowout preventer positioned at a seafloor. However, the assessment
methodology also may be used for fatigue monitoring with respect to
locations along a riser and/or other subsea tubing strings. The
improved fatigue life monitoring enables the overall lifetime of
components, e.g. tools, to be maximized by lowering the risk of
failure due to fatigue damage. The system and methodology address
many of the technical challenges associated with strain monitoring
in a subsea environment, including challenges associated with
pressure and temperature considerations and data transmission from
a seabed to a rig floor. A surface processing system, e.g.
computer-based processing system, or other processing system may be
used to facilitate fatigue related data retrieval and archiving of
the data for individual assets and jobs.
[0019] In some applications, real-time fatigue monitoring is
enabled by transmitting sensor data, e.g. strain sensor data, from
a subsea location to a surface processing system. A sensor or
sensors may be disposed along the subsea tubing string for
monitoring stresses experienced by the subsea tubing string due to,
for example, movement of the surface rig, wave motion in the ocean,
and/or other operationally induced stresses. For example, the
system and methodology may be used to continuously monitor for
extreme stresses caused by unusual rig movement or other types of
load influences on the tubing string. Based on the data collected,
the remaining life of a given tool may be calculated and
subsequently updated to ensure an effective and efficient
maintenance schedule with respect to the given tool.
[0020] In a specific example, strain sensors or other suitable
sensors are deployed along a tool in the form of a subsea tubing
string, e.g. a subsea landing string. The sensors disposed along
the subsea landing string may be used for monitoring tool health at
discrete, periodic locations along the length of the subsea landing
string. The data collected may be used to ensure an adequate
maintenance system with respect to the subsea landing string and
its various components. The sensors and cooperating monitoring
equipment enable measurement, recording, and transmission of strain
data which is used to calculate fatigue related effects at various
locations, e.g. at various devices, of the subsea landing string.
The data obtained regarding fatigue related effects at specific
locations can be used to establish fatigue life predictions. The
sensor data also may be used with an appropriate computer modeling
system to interpolate strain and fatigue calculations from measured
points to less accessible points.
[0021] Referring generally to FIG. 1, an embodiment of a well
system 20 is illustrated. In this embodiment, well system 20 is
illustrated in an offshore environment in which surface equipment
22, e.g. a rig, is positioned at a sea surface 24 generally over a
wellbore 26. The wellbore 26 is drilled into a subterranean
formation 28 through a seafloor 30. In this example, the subsurface
equipment 32 is located over wellbore 26 at seafloor 30. By way of
example, the subsurface equipment 32 may comprise a blowout
preventer 34.
[0022] A subsea tubing string 36 extends into cooperation with the
blowout preventer 34. By way of example, the subsea tubing string
36 may comprise a subsea landing string 38 which extends into an
interior of the blowout preventer 34. Additionally, a riser 40 may
be deployed to extend from the rig 22 down toward blowout preventer
34. The riser 40 also is in the form of a subsea tubing string and
may comprise various features, such as a quick connect 42. As
described in greater detail below, a sensor system may be used to
obtain data at specific locations so as to monitor fatigue at
specific subsea tubing string locations resulting from loading
caused by waves, currents, or other environmental or operational
factors. Sensors may be deployed along landing string 38 and/or at
other devices, e.g. at quick connect 42, to monitor for fatigue
effects.
[0023] Fatigue related data may be processed on a suitable
processing system 44, such as a surface, computer-based processing
system. However, data processing may be performed in whole or in
part at a subsea location, a surface location, and/or a remote
location. Depending on the type of sensor system utilized for
monitoring fatigue, the processing system 44 may comprise
appropriate software modules 46 programmed to process data from the
sensor system and to provide, for example, fatigue life predictions
for specific subsea tubing string components. By way of example,
the processing system 44 may be programmed with a suitable modeling
program 48 which uses sensor data related to stresses incurred and
historical stress data to determine estimates of fatigue life with
respect to specific components, e.g. devices, disposed along one or
more subsea tubing strings.
[0024] Referring generally to FIG. 2, an example of subsea tubing
string 36 is illustrated in the form of subsea landing string 38
disposed within an interior 50 of blowout preventer 34. In this
example, the subsea landing string 38 comprises various devices,
such as a retainer valve 52 and a subsea test tree 54 coupled by
tubular members 56, e.g. mandrels. A sensor system 58 comprises a
sensor 60, and often a plurality of sensors 60, disposed along the
subsea landing string 38. The sensors 60 are mounted at specific
locations which facilitate collection of useful fatigue related
data. In some applications, sensors 60 may be mounted directly to a
device susceptible to fatigue, e.g. retainer valve 52 or subsea
test tree 54. However, sensors 60 also may be mounted proximate the
devices, e.g. along tubular members 56 coupled with the subject
device, and data related to fatigue may be interpolated from the
actual measurement locations to less accessible locations.
[0025] As further illustrated in FIG. 3, the sensors 60 may be
positioned and arranged to monitor stresses incurred by the subsea
landing string 38 or other subsea tubular string. By way of
example, the sensors 60 may be positioned to monitor tensile loads
as represented by arrow 62. The sensors 60 also may be used to
monitor a variety of other types of loading experienced by the
subsea landing string 38, such as torque loads, compressive loads,
and/or oscillatory loads, e.g. wave loading, as represented by
arrow 64. Depending on the application, the sensors 60 may comprise
strain gauges, accelerometers, and/or other suitable sensors able
to collect data related to the stress loading which can affect
fatigue life of a given component/device.
[0026] Referring to FIG. 4, for example, an embodiment is
illustrated in which sensors 60 are in the form of strain gauges
66. In this example, a plurality of the strain gauges 66 is secured
to a housing 68 of the subsea landing string 38. By way of example,
each strain gauge 66 may be coupled with a data storage and
transmitter device 70 which also is secured to the subsea landing
string housing 68. According to some embodiments, each device 70
may be mounted to the housing 68 via a ceramic insulator 72.
[0027] In some applications, a single strain gauge 66 may be
affixed to the landing string housing 68, e.g. to an exterior
surface of one of the tubular members 56 or one of the devices 52,
54. However, a plurality of strain gauges 66 or other types of
sensors 60 may be used for a variety of reasons. For example,
multiple strain gauges, e.g. multiple couples of strain gauges, may
be used for redundancy. Additionally, monitoring of certain types
of strain, e.g. strain resulting from bending, may be improved by
using two or more strain gauges. As described in greater detail
below, the data acquired by sensors 60/strain gauges 66 may be
transmitted to a downhole storage device or to surface storage. In
some applications, for example, the data obtained by sensors 60 may
be transferred to the surface via a suitable wireless telemetry
system.
[0028] As illustrated in FIG. 5, the subsea landing string 38 may
be constructed in various configurations with different types of
devices and components depending on the parameters of a given
application. For example, the retainer valve 52 and subsea test
tree 54 may comprise or work in cooperation with other features and
devices. In the example illustrated in FIG. 5, the subsea test tree
54 comprises other components, such as a latch 74, a flapper valve
76, and a ball valve 78. The sensors 60 may be placed on these
components to measure strain data directly or on members coupled
with the these components for interpolation of strain data at
specific, less accessible locations along the subsea landing string
38.
[0029] By way of example, a location 80 susceptible to fatigue may
be at a threaded section 82, as illustrated in FIG. 6. In this
example, the threaded region 82 is formed by a thin region or
regions at the ends of tubular sections being joined. In some
applications, the tubular members 56 may be joined to each other or
to adjacent devices, e.g. devices 52, 54, by threaded region 82
thus establishing location 80 susceptible to fatigue. Sometimes
placement of the sensor or sensors 60 directly at location 80 is
difficult. However, the sensors 60 may be located proximate the
location 80, as illustrated, and a transfer function may be used
between the stresses/loads measured at the locations of sensors 60
and the loads at the location 80 susceptible to fatigue. By way of
example, a finite element analysis may be performed by processing
system 44 (or by another suitable processing system) to create the
transfer function between measured loads at the sensor location and
the loads acting on the devices at fatigue location 80. It should
be noted the locations 80 susceptible to fatigue may occur at many
types of connections and/or at many other positions along the
subsea tubing string 36.
[0030] Referring generally to FIG. 7, an embodiment is illustrated
in which a data recorder 84 is communicatively coupled with the
sensor or sensors 60. By way of example, data recorder 84 may be in
the form of a strain gauge recorder for collecting strain gauge
data from one or more of the sensors 60. As illustrated, the data
recorder 84 may be mounted at a subsea position along, for example,
the subsea landing string 38. In some applications, the strain data
and/or other data from data recorder 84 is retrieved when the
subsea landing string 38 is retrieved to the surface. However, the
data recorder also may be coupled with a telemetry system 86, as
illustrated in Figure 8. The telemetry system 86 may be a wired
telemetry system or a wireless, e.g. acoustic, telemetry system
able to relay data from sensors 60 to the surface in real-time.
[0031] In a specific example, sensors 60 comprise strain gauges 66
which are connected to data recorder 84, and the data recorder is
in the form of a strain gauge analog input box. The strain gauge
analog input box may be connected to a telemetry system 86, such as
the Muzik.TM. system available from Schlumberger Corporation. The
Muzik.TM. system enables recording of sensor data in recorder mode
or in recorder plus transmit/receive mode. If data is collected in
record mode, the data may be exported once the data recorder 84 is
retrieved to the surface. In the recorder plus transmit/receive
mode at least some of the sensor data may be transmitted to the
surface in real time.
[0032] Whether in real-time or at a later point in time, the sensor
data, e.g. strain data, is provided to processing system 44. As
illustrated in FIG. 9, some applications utilize real-time transfer
of data to the surface and to processing system 44 via telemetry
system 86 which may comprise wireless telemetry devices 88, e.g.
acoustic devices, to facilitate the real-time, wireless transfer of
sensor data. The real-time transfer of data enables continual
monitoring of specific subsea locations 80 along the subsea tubing
string 36, e.g. along subsea landing string 38, that are
susceptible to fatigue.
[0033] The data collected by sensors 60 may be stored in a logbook
90 of processing system 44. For example, data may be collected from
accelerometer sensors 60 and/or strain gauge sensors 60 and
continuously used to update the logbook 90. Examples of data
collected and stored in logbook 90 may include the number of stress
events, maximum values of bending moments, mean values of bending
moments, tensile loading, compressive loading, and/or other
stress-related data at a specific location or locations 80 that can
affect the fatigue life of a given component, e.g. device.
[0034] The processing system 44 also may store the ongoing data
collected and may establish a database which tracks the collected
data related to, for example, fatigue accumulation, maximum fatigue
life expectation, and remaining lifecycle, for each selected
component and each selected job. As described above, transfer
functions, e.g. finite element analysis transfer functions, may be
used to establish an equivalent fatigue evaluation at a location
separate from the actual sensor locations. The logbook 90 may be
updated continuously or after each job.
[0035] The data collected in logbook 90 may be continually
processed via, for example, modeling program 48 to determine and
update fatigue life estimates at specific locations 80, e.g. at
specific devices, along the subsea landing string 38 or other
tubing string. For example, the processing system 44 may utilize
suitable software modules 46 and modeling programs 48 to perform
the desired transfer functions and to perform the conversion of
sensor data into estimates of fatigue life. In some applications,
sensors 60 may comprise both strain gauges 66 to provide strain
data and accelerometers to provide additional data, e.g.
orientation, pipe angle, strain. The data from the different types
of sensors 60 is then processed according to the desired models or
algorithms to provide estimates of fatigue life at the
location/devices susceptible to fatigue.
[0036] In some applications, the processing system 44 and modeling
program 48 may utilize historical test data in which various types
of tubing string components/devices have been tested to failure
based on different types of strains. By matching measured strain
data with historical test data for a comparable component/device,
the processing system 44 is able to output and display estimates of
fatigue life. As illustrated in FIG. 10, for example, graphical
estimates 92 of remaining component life may be output on a display
94 of processing system 44. The estimates of fatigue life may then
be used automatically or by intervention of an operator to adjust
parameters of the operation, replace specific components, and/or
take other actions to maximize the useful life of the subsea tubing
string.
[0037] In an operational example, the locations 80 susceptible to
fatigue due to stress loading are initially determined. The
locations 80 may be on specific devices, at connections, e.g.
threaded connections or moving pipe-in-pipe connections, or at
other locations susceptible to fatigue during the subsea operation.
In various subsea operations, for example, locations 80 are
selected along subsea landing string 38 and/or at quick connect 42.
Sensors 60 may be positioned at the location(s) 80 or at a
suitable, related location which enables interpolation of stress
loading experienced at the location(s) 80. The sensors 60 are then
used to obtain loading data resulting from stresses to the tubing
string.
[0038] The collected data may be stored in logbook 90 and processed
via processing system 44 to make the desired mathematical
conversions and to perform the desired modeling, e.g. comparison
with historical data, to determine the effects of loading as it
pertains to fatigue at the location(s) 80. The estimated effects on
fatigue life of the component/location of interest may be output
to, for example, display 94 for evaluation by an operator.
Depending on the application, the output of results may be ongoing
in real-time or may be at desired intervals.
[0039] Depending on the application, the well system 20 may have a
variety of configurations and/or components. Similarly, the fatigue
monitoring methodology may be used with many types of tubing
strings in a variety of subsea applications. Depending on the
application, a single sensor or a plurality of sensors may be used
to obtain data at an individual location or multiple locations.
Additionally, the sensor or sensors may comprise strain gauges
and/or other types of sensors, e.g. accelerometers, to facilitate
the accumulation of desired data. The data also may be processed
according to a variety of computer models and/or according to
various algorithms to determine the estimates of fatigue life for a
given type of component.
[0040] Although a few embodiments of the disclosure have been
described in detail above, those of ordinary skill in the art will
readily appreciate that many modifications are possible without
materially departing from the teachings of this disclosure.
Accordingly, such modifications are intended to be included within
the scope of this disclosure as defined in the claims.
* * * * *