CA2840463A1 - Gas lift kickover system - Google Patents
Gas lift kickover system Download PDFInfo
- Publication number
- CA2840463A1 CA2840463A1 CA2840463A CA2840463A CA2840463A1 CA 2840463 A1 CA2840463 A1 CA 2840463A1 CA 2840463 A CA2840463 A CA 2840463A CA 2840463 A CA2840463 A CA 2840463A CA 2840463 A1 CA2840463 A1 CA 2840463A1
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- CA
- Canada
- Prior art keywords
- valve
- tool
- changing system
- detection device
- leak detection
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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- 238000001514 detection method Methods 0.000 claims abstract description 84
- 238000009434 installation Methods 0.000 claims abstract description 62
- 238000000034 method Methods 0.000 claims abstract description 20
- 239000000835 fiber Substances 0.000 claims description 45
- 230000003287 optical effect Effects 0.000 claims description 29
- 230000007547 defect Effects 0.000 claims description 24
- 239000012530 fluid Substances 0.000 claims description 24
- 230000005540 biological transmission Effects 0.000 claims description 5
- 230000004913 activation Effects 0.000 claims description 3
- 238000004873 anchoring Methods 0.000 claims description 3
- 230000001427 coherent effect Effects 0.000 claims description 3
- 238000004891 communication Methods 0.000 claims description 3
- 238000005086 pumping Methods 0.000 claims description 3
- 239000007789 gas Substances 0.000 description 33
- 239000003921 oil Substances 0.000 description 9
- 238000004519 manufacturing process Methods 0.000 description 6
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 4
- 238000012360 testing method Methods 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 230000004888 barrier function Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 239000010779 crude oil Substances 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 239000003345 natural gas Substances 0.000 description 2
- 239000013307 optical fiber Substances 0.000 description 2
- 238000012795 verification Methods 0.000 description 2
- 239000011499 joint compound Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B23/00—Apparatus for displacing, setting, locking, releasing, or removing tools, packers or the like in the boreholes or wells
- E21B23/03—Apparatus for displacing, setting, locking, releasing, or removing tools, packers or the like in the boreholes or wells for setting the tools into, or removing the tools from, laterally offset landing nipples or pockets
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/12—Methods or apparatus for controlling the flow of the obtained fluid to or in wells
- E21B43/121—Lifting well fluids
- E21B43/122—Gas lift
- E21B43/123—Gas lift valves
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/10—Locating fluid leaks, intrusions or movements
- E21B47/103—Locating fluid leaks, intrusions or movements using thermal measurements
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/10—Locating fluid leaks, intrusions or movements
- E21B47/107—Locating fluid leaks, intrusions or movements using acoustic means
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/12—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling
- E21B47/13—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling by electromagnetic energy, e.g. radio frequency
- E21B47/135—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling by electromagnetic energy, e.g. radio frequency using light waves, e.g. infrared or ultraviolet waves
Abstract
The present invention relates to a valve changing system (1) for retrieving and installing a valve (2) in a well (3). The valve changing system comprises a tool string comprising a retrieving tool (4) for taking out the valve, comprising a housing (5) and an arm (6) pivotally connected with the housing, said arm having a connector (7) for connection to the valve, and an installation tool (9) for installing another valve connected with the retrieving tool forming a tool string (8), the installation tool comprising a housing (10) and an arm (11) which is pivotally connected with the housing and has a connector (12) for connection to another valve, a driving tool (13) connected with the installation tool and the retrieving tool for providing an axial movement in order to install or retrieve the valve, and a leak detection device (14) for detecting temperature and/or acoustic variations, the leak detection device being arranged in one end of the tool string. Furthermore the invention relates to a valve changing method.
Description
GAS LIFT KICKOVER SYSTEM
Field of the Invention The present invention relates to a valve changing system for retrieving and installing a valve in a well. Furthermore, the invention relates to a valve changing method.
Background Art Gas lift kickover tools are used to take out a gas lift valve in a side pocket in a well and, in a next run, to put in a new gas lift valve. Gas lift valves are arranged in a side pocket in the production casing for letting gas into the casing from the annulus surrounding the casing which is filled with gas. The gas lift valves are, together with the casing, part of the primary barrier in a well and it is therefore extremely important that a gas lift valve is not leaking as pressure is then built up in the annulus. If pressure builds up in the annulus due to a leaking valve or if the production decreases, the valve is changed. After having changed a gas lift valve, a new valve is installed in a next run and the well is tested by taking off the pressure in the annulus to verify that the valve is mounted correctly and functions as intended. If the pressure in the annulus does not increase, the valve does not leak and the primary barrier is maintained. The process of taking off the pressure and pressurising the annulus again lasts around three days in which the well is not producing. Thus, the changing of a gas lift valve is performed in two runs if the operation is successful on the first attempt and subsequently, the well is out of production for at least three days to be tested. When intervening a well to change a gas lift, the well is not producing, and the sooner the operation is completed, the sooner production can be resumed.
Summary of the Invention It is an object of the present invention to wholly or partly overcome the above disadvantages and drawbacks of the prior art. More specifically, it is an object to provide an improved system for changing gas lift valves which is capable of changing a gas lift valve and verify that the valves are mounted correctly so that they do not leak and function satisfactorily in less time than the known systems.
The above objects, together with numerous other objects, advantages, and features, which will become evident from the below description, are accomplished by a solution in accordance with the present invention by a valve changing system for retrieving and installing a valve in a well, comprising:
- a tool string comprising:
- a retrieving tool for taking out the valve, comprising a housing and an arm pivotally connected with the housing, said arm having a connector for connection to the valve, and - an installation tool for installing another valve connected with the retrieving tool forming a tool string, the installation tool comprising a housing and an arm which is pivotally connected with the housing and has a connector for connection to another valve, - a driving tool connected with the installation tool and the retrieving tool for providing an axial movement in order to install or retrieve the valve, and - a leak detection device for detecting temperature and/or acoustic variations, the leak detection device being arranged in one end of the tool string.
By having a system comprising both a retrieval and installation tool, replacing of a valve can be performed in one run. Furthermore, by having a leak detection device, testing of the valve can be made in the same run by submerging the system into the well so that the leak detection device is arranged opposite the valves and all the valves can be tested without having to decrease the pressure in the annulus. A replacement operation can then be performed in half a day instead of in three days.
When having a leak detection device to test the valves, also horizontal wells having valves can easily be tested.
By having the leak detection device in the end of the tool string, the leak detection device can be arranged so that it is affected by any variations all around the interior of the casing. The leak detection device arranged in front of or behind the tool string is not shielded and influenced by the tool string itself.
Leak detection devices arranged at one side of the tool housing are not influenced by the variations at the opposite side of the housing since the tool housing shields for these variations. The leak detection device arranged in front of the tool string or behind the tool string is equally affected by all variations along the circumference of the casing and is thus not shielded by the tool string.
Field of the Invention The present invention relates to a valve changing system for retrieving and installing a valve in a well. Furthermore, the invention relates to a valve changing method.
Background Art Gas lift kickover tools are used to take out a gas lift valve in a side pocket in a well and, in a next run, to put in a new gas lift valve. Gas lift valves are arranged in a side pocket in the production casing for letting gas into the casing from the annulus surrounding the casing which is filled with gas. The gas lift valves are, together with the casing, part of the primary barrier in a well and it is therefore extremely important that a gas lift valve is not leaking as pressure is then built up in the annulus. If pressure builds up in the annulus due to a leaking valve or if the production decreases, the valve is changed. After having changed a gas lift valve, a new valve is installed in a next run and the well is tested by taking off the pressure in the annulus to verify that the valve is mounted correctly and functions as intended. If the pressure in the annulus does not increase, the valve does not leak and the primary barrier is maintained. The process of taking off the pressure and pressurising the annulus again lasts around three days in which the well is not producing. Thus, the changing of a gas lift valve is performed in two runs if the operation is successful on the first attempt and subsequently, the well is out of production for at least three days to be tested. When intervening a well to change a gas lift, the well is not producing, and the sooner the operation is completed, the sooner production can be resumed.
Summary of the Invention It is an object of the present invention to wholly or partly overcome the above disadvantages and drawbacks of the prior art. More specifically, it is an object to provide an improved system for changing gas lift valves which is capable of changing a gas lift valve and verify that the valves are mounted correctly so that they do not leak and function satisfactorily in less time than the known systems.
The above objects, together with numerous other objects, advantages, and features, which will become evident from the below description, are accomplished by a solution in accordance with the present invention by a valve changing system for retrieving and installing a valve in a well, comprising:
- a tool string comprising:
- a retrieving tool for taking out the valve, comprising a housing and an arm pivotally connected with the housing, said arm having a connector for connection to the valve, and - an installation tool for installing another valve connected with the retrieving tool forming a tool string, the installation tool comprising a housing and an arm which is pivotally connected with the housing and has a connector for connection to another valve, - a driving tool connected with the installation tool and the retrieving tool for providing an axial movement in order to install or retrieve the valve, and - a leak detection device for detecting temperature and/or acoustic variations, the leak detection device being arranged in one end of the tool string.
By having a system comprising both a retrieval and installation tool, replacing of a valve can be performed in one run. Furthermore, by having a leak detection device, testing of the valve can be made in the same run by submerging the system into the well so that the leak detection device is arranged opposite the valves and all the valves can be tested without having to decrease the pressure in the annulus. A replacement operation can then be performed in half a day instead of in three days.
When having a leak detection device to test the valves, also horizontal wells having valves can easily be tested.
By having the leak detection device in the end of the tool string, the leak detection device can be arranged so that it is affected by any variations all around the interior of the casing. The leak detection device arranged in front of or behind the tool string is not shielded and influenced by the tool string itself.
Leak detection devices arranged at one side of the tool housing are not influenced by the variations at the opposite side of the housing since the tool housing shields for these variations. The leak detection device arranged in front of the tool string or behind the tool string is equally affected by all variations along the circumference of the casing and is thus not shielded by the tool string.
In one embodiment, the tools may be aligned along a tool string centre axis and the leak detection device may be arranged substantially in line with the tool centre axis.
Also, the leak detection device may be arranged in front of one of the installation tool and the retrieving tool or arranged behind one of the installation tool and the retrieving tool closest to a well head of the well.
Further, the leak detection device may be a pressure sensor, a temperature sensor, a flow meter or an acoustic sensor, such as a microphone.
In an embodiment, the leak detection device may be a fibre optical cable sensor.
Moreover, the fibre optical cable sensor may comprise a single mode fibre operating at a wavelength of 1000 nm-2000 nm, preferably at a wavelength of 1200 nm-1800 nm, and more preferably at a wavelength of 1400 nm-1600 nm, such as at a wavelength of 1550 nm.
Further, the fibre optical cable sensor may operate at an attenuation of 0.1-0.3 dB/km.
The valve changing system as described above may further comprise a wireline for powering the tools.
Additionally, the leak detection device is fibre optical cable sensor which may be part of a wireline, an e-line or a slickline connected to the tool string in order to retrieve the tool string.
Furthermore, the fibre optical cable sensor may be a distribution temperature sensor and/or a distribution acoustic sensor.
Additionally, the tool may comprise a laser for sending light pulses through the leak detection device being a fibre optical cable sensor.
In an embodiment, the tool may comprise a detector for detecting the intensity of the reflected light pulses.
Also, the leak detection device may be arranged in front of one of the installation tool and the retrieving tool or arranged behind one of the installation tool and the retrieving tool closest to a well head of the well.
Further, the leak detection device may be a pressure sensor, a temperature sensor, a flow meter or an acoustic sensor, such as a microphone.
In an embodiment, the leak detection device may be a fibre optical cable sensor.
Moreover, the fibre optical cable sensor may comprise a single mode fibre operating at a wavelength of 1000 nm-2000 nm, preferably at a wavelength of 1200 nm-1800 nm, and more preferably at a wavelength of 1400 nm-1600 nm, such as at a wavelength of 1550 nm.
Further, the fibre optical cable sensor may operate at an attenuation of 0.1-0.3 dB/km.
The valve changing system as described above may further comprise a wireline for powering the tools.
Additionally, the leak detection device is fibre optical cable sensor which may be part of a wireline, an e-line or a slickline connected to the tool string in order to retrieve the tool string.
Furthermore, the fibre optical cable sensor may be a distribution temperature sensor and/or a distribution acoustic sensor.
Additionally, the tool may comprise a laser for sending light pulses through the leak detection device being a fibre optical cable sensor.
In an embodiment, the tool may comprise a detector for detecting the intensity of the reflected light pulses.
Furthermore, the retrieving tool may further comprise a contact for detecting a connection between the connector and the valve.
Hereby it is ensured that the valve changing system is not retracted from the well before the defect valve is removed.
Said contact may be in communication with an activation device of the installation tool.
Hereby it is ensured that the installation tool is not activated until the installation tool has proper contact with the defect valve to be retrieved, and thus the installation of a functioning valve can be initiated.
The valve changing system according to the present invention may further comprise a tool connection for connecting the retrieving tool with the installation tool.
In one embodiment, the driving tool may comprise a stroking tool comprising a motor and a pump driven by the motor, the pump pumping fluid into a piston chamber in the stroking tool moving a piston connected with a piston shaft, said shaft being connected with the retrieving tool or installation tool for transferring the axial movement.
Moreover, the driving tool may comprise a downhole tractor, said driving tool also being capable of driving the system forward in the well.
Also, the driving tool may comprise wheels arranged on a wheel arm and may have an electrical motor driving a pump which drives the wheel to move the system forward in the well.
Further, the driving tool may comprise an electrical power device to power the tools.
In one embodiment, the piston may divide the piston chamber of the stroking tool into a first chamber part and a second chamber part, and the pump may pump fluid into the first chamber part and suck fluid out of the second chamber part.
Also, the stroking tool may comprise several pistons, each piston being arranged in a piston chamber.
The valve changing system according to the present invention may further 5 comprise an anchoring section.
Said valve changing system may comprise sensors arranged to detect if the arm is in its retracted or extending position.
Furthermore, the present invention relates to a valve changing method for changing a valve in a well, comprising the steps of:
- entering the valve changing system according to the present invention, - moving the valve changing system so that the leak detection device passes a plurality of valves in order to detect which valve is defect, - moving the valve changing system to a position so that the retrieving tool is opposite the defect valve, - retrieving the defect valve by means of the retrieving tool, - moving the valve changing system so that the installation tool is in the position, and - installing another valve by means of the installation tool.
Moreover, the valve changing method as described above may further comprise the step of moving the valve changing system so that the leak detection device passes the installed valve, and detecting temperature and/or acoustic variations opposite the at least one valve by means of the leak detection device.
Also, the present invention relates to a valve changing method comprising the steps of:
- entering the valve changing system according to the present invention, - moving the valve changing system to a position in which the retrieving tool is opposite at least one valve in the well, - retrieving the valve by means of the retrieving tool, - moving the valve changing system so that the installation tool is in the position, - installing another valve by means of the installation tool, - moving the valve changing system so that the leak detection device passes the installed valve, and - detecting temperature and/or acoustic variations opposite the at least one valve by means of the leak detection device.
The step of detecting acoustic variations may be performed using Rayleigh scatter based sensing.
In the valve changing method as described above, the leak detection device may be a fibre optical sensor and may further comprise the step of sending a coherent laser light pulse along the leak detection device being a fibre optical cable sensor.
In addition, the valve changing method as described above may comprise the step of measuring of the intensity of the reflected laser light as a function of time after transmission of the laser pulse.
A laser pulse may be sent through the optic fibre and in the event of a leak, sound and temperature may influence the fibre at that position to scatter the laser light. The intensity of the reflected light is measured as a function of time after transmission of the laser pulse. The reflected light at the position of the leak returns before the rest of the laser pulse has had time to travel the full length of the fibre and back, and thus the position of the leak and thus which gas lift valve is leaking can be determined. The next laser pulse can be sent along the fibre when the previous laser pulse has travelled the full length and back. Changes in the reflected intensity of successive pulses from the same region of fibre opposite the leak are caused by changes in the optical path length of that section of fibre and confirm the position of the leak. This type of system is very sensitive to both strain, noise and temperature variations of the fibre, and measurements can be made simultaneously at all sections of the fibre.
In addition, the valve changing method as described above may further comprise the step of adjusting the installed valve to be more open or closed.
Moreover, the valve changing method as described above may further comprise the step of closing the well while conducting an acoustic detection by means of the leak detection device.
Hereby it is ensured that the valve changing system is not retracted from the well before the defect valve is removed.
Said contact may be in communication with an activation device of the installation tool.
Hereby it is ensured that the installation tool is not activated until the installation tool has proper contact with the defect valve to be retrieved, and thus the installation of a functioning valve can be initiated.
The valve changing system according to the present invention may further comprise a tool connection for connecting the retrieving tool with the installation tool.
In one embodiment, the driving tool may comprise a stroking tool comprising a motor and a pump driven by the motor, the pump pumping fluid into a piston chamber in the stroking tool moving a piston connected with a piston shaft, said shaft being connected with the retrieving tool or installation tool for transferring the axial movement.
Moreover, the driving tool may comprise a downhole tractor, said driving tool also being capable of driving the system forward in the well.
Also, the driving tool may comprise wheels arranged on a wheel arm and may have an electrical motor driving a pump which drives the wheel to move the system forward in the well.
Further, the driving tool may comprise an electrical power device to power the tools.
In one embodiment, the piston may divide the piston chamber of the stroking tool into a first chamber part and a second chamber part, and the pump may pump fluid into the first chamber part and suck fluid out of the second chamber part.
Also, the stroking tool may comprise several pistons, each piston being arranged in a piston chamber.
The valve changing system according to the present invention may further 5 comprise an anchoring section.
Said valve changing system may comprise sensors arranged to detect if the arm is in its retracted or extending position.
Furthermore, the present invention relates to a valve changing method for changing a valve in a well, comprising the steps of:
- entering the valve changing system according to the present invention, - moving the valve changing system so that the leak detection device passes a plurality of valves in order to detect which valve is defect, - moving the valve changing system to a position so that the retrieving tool is opposite the defect valve, - retrieving the defect valve by means of the retrieving tool, - moving the valve changing system so that the installation tool is in the position, and - installing another valve by means of the installation tool.
Moreover, the valve changing method as described above may further comprise the step of moving the valve changing system so that the leak detection device passes the installed valve, and detecting temperature and/or acoustic variations opposite the at least one valve by means of the leak detection device.
Also, the present invention relates to a valve changing method comprising the steps of:
- entering the valve changing system according to the present invention, - moving the valve changing system to a position in which the retrieving tool is opposite at least one valve in the well, - retrieving the valve by means of the retrieving tool, - moving the valve changing system so that the installation tool is in the position, - installing another valve by means of the installation tool, - moving the valve changing system so that the leak detection device passes the installed valve, and - detecting temperature and/or acoustic variations opposite the at least one valve by means of the leak detection device.
The step of detecting acoustic variations may be performed using Rayleigh scatter based sensing.
In the valve changing method as described above, the leak detection device may be a fibre optical sensor and may further comprise the step of sending a coherent laser light pulse along the leak detection device being a fibre optical cable sensor.
In addition, the valve changing method as described above may comprise the step of measuring of the intensity of the reflected laser light as a function of time after transmission of the laser pulse.
A laser pulse may be sent through the optic fibre and in the event of a leak, sound and temperature may influence the fibre at that position to scatter the laser light. The intensity of the reflected light is measured as a function of time after transmission of the laser pulse. The reflected light at the position of the leak returns before the rest of the laser pulse has had time to travel the full length of the fibre and back, and thus the position of the leak and thus which gas lift valve is leaking can be determined. The next laser pulse can be sent along the fibre when the previous laser pulse has travelled the full length and back. Changes in the reflected intensity of successive pulses from the same region of fibre opposite the leak are caused by changes in the optical path length of that section of fibre and confirm the position of the leak. This type of system is very sensitive to both strain, noise and temperature variations of the fibre, and measurements can be made simultaneously at all sections of the fibre.
In addition, the valve changing method as described above may further comprise the step of adjusting the installed valve to be more open or closed.
Moreover, the valve changing method as described above may further comprise the step of closing the well while conducting an acoustic detection by means of the leak detection device.
Brief Description of the Drawings The invention and its many advantages will be described in more detail below with reference to the accompanying schematic drawings, which for the purpose of illustration show some non-limiting embodiments and in which Fig. 1 shows a valve changing system in a casing in a well, Fig. 2 shows another valve changing system in a casing in a well, Figs. 3A-D show a retrieving tool retrieving a valve, Figs. 3E-H show an installation tool installing another valve, Fig. 4 shows a cross-sectional view of a wireline comprising a fibre optical cable sensor, and Fig. 5 shows another embodiment of the valve changing system.
All the figures are highly schematic and not necessarily to scale, and they show only those parts which are necessary in order to elucidate the invention, other parts being omitted or merely suggested.
Detailed description of the invention Fig. 1 shows a valve changing system 1 for retrieving a valve 2 in a well 3 and installing another valve. The valve changing system 1 comprises a retrieving tool 4 for taking out the valve and an installation tool 9 for installing another valve.
The installation tool 9 is connected with the retrieving tool forming a tool string 8.
The tool string 8 is connected with a driving tool 13 for providing an axial movement in order to install or retrieve the valve. The valve changing system further comprises a leak detection device 14 for detecting temperature and/or acoustic variations. The leak detection device is arranged in one end of the tool string closest to the top of the well so that when the tools are moved forward in the well, the leak detection device can test the valves in the well. This end of the tool string comprises an electrical power device 20 powering a motor 15 which drives a pump 16. The pump 16 is part of the driving tool 13 providing the axial movement of the retrieving tool and the installation tool.
The tools are aligned along a tool string centre axis and the leak detection device is arranged substantially in line with the tool centre axis. By having the leak detection device in the end of the tool string, either in the end closest to the top of the well or in the opposite end in front of the tool string, the leak detection device can be arranged so that it is affected by any variations all around the interior of the casing. A leaking gas lift valve leaks bubbles into the well fluid and thus generates sound variations, and the gas most often has a temperature different from that of the well fluid, resulting in the gas leak also generating temperature variation. Furthermore, the gas expands in the fluid, resulting in an increased flow. The leak detection device arranged in front of or behind the tool string is not shielded and influenced by the tool string itself. If the leak detection device is arranged at one side of the tool housing, the leak detection device is not influenced by the variations at the opposite side of the housing since the tool housing shields for these variations. Thus, if the leak detection device is arranged on the side opposite to where the side pocket is located, the variations may not be detected and the defect valve may seem in order. The leak detection device arranged in front of the tool string or behind the tool string is equally affected by all variations along the circumference of the casing and is thus not shielded by the tool string. Hence, the leak detection device arranged at one end of the tool string is capable of detecting a gas leak and thus a defect valve even though such leak is positioned in a side pocket. Furthermore, the detection of the valve leaking and hence requiring replacement can be performed using only one fibre cable since it is arranged in line with the centre axis.
In Fig. 3A, the leak detection device 14 is arranged in front of one of the installation tool and the retrieving tool and in Figs. 1 and 2 the leak detection device 14 is arranged behind one of the installation tool and the retrieving tool closest to a well head of the well.
The leak detection device may be any kind of leak detection device such as a pressure sensor, a temperature sensor, a flow meter or an acoustic sensor, such as a microphone. A leaking gas lift valve leaks bubbles into the well fluid and thus generates sound variations, and the gas most often has a temperature different from that of the well fluid, resulting in the gas leak also generating temperature variation. Furthermore, the gas expands in the fluid, resulting in an increased flow. Thus, leak detection devices capable of sensing acoustic changes, temperature changes, pressure changes and/or flow changes can be suitable as a leak detection device.
In Fig. 1, the tool comprises a laser 51 for sending light pulses through the leak detection device 14 being a fibre optical cable sensor 14. A laser pulse is sent through the optical fibre of the fibre optical cable sensor and in the event of a leak, sound and perhaps also a temperature difference influence the optic fibre at that position by scattering the laser light. The intensity of the reflected light is measured as a function of time after transmission of the laser pulse of a detector 52 in the sensor 14. The reflected light at the position of the leak returns before the rest of the laser pulse has had time to travel the full length of the fibre and back, and thus the position of the leak and thus which gas lift valve is leaking can be determined.
The next laser pulse can be sent along the fibre when the previous laser pulse has travelled the full length and back. Changes in the reflected intensity of successive pulses from the same region of fibre opposite the leak are caused by changes in the optical path length of that section of fibre and confirm the position of the leak. This type of system is very sensitive to strain, noise and temperature variations of the fibre.
The retrieving tool comprises a housing 5 and an arm 6 pivotally connected with the housing. The arm has a connector 7 for connecting to the valve to be retrieved. The installation tool 9 also comprises a housing 10 and an arm 11 pivotally connected with the housing, and the arm has a connector 12 releasably connected to the new valve. The arms of the tools comprise two arm parts pivotally connected so that the first arm part is connected to the housing 10 and the second arm part is connected to the valve 2. Both the retrieving tool and the installation tool are a kind of kickover tool. The installation tool has a tool connection 39 arranged in an end opposite the driving tool transferring the axial movement of the driving tool to the retrieving tool so that only one driving tool is needed for movement of both arms of the tools. If the retrieving tool is arranged closest to the driving tool, the retrieving tool has a tool connection arranged in an end opposite the driving tool transferring the axial movement of the driving tool to the installation tool.
In Fig. 3A, the retrieving tool 4 is arranged opposite the valve 2 to be replaced.
In Fig. 3B, the arm 6 of the retrieving tool 4 is in its extended position, ready to be subjected to an axial movement from the driving tool 13 to engage the valve 2 by the connector of the arm 6. In Fig. 3C, the retrieving tool 4 has been 5 subjected to the axial movement and the arm 6 is connected to the valve 2, ready for retrieval. In Fig. 3D, the retrieving tool 4 is retrieving the valve 2 and the retrieving tool 4 is moved further down the well so that the installation tool 9 is arranged in the position opposite the opening 40 in which the valve is to be installed. In Fig. 3E, the arm 11 of the installation tool 9 is extended and the 10 valve is arranged opposite the opening 40 into which the valve is to be inserted.
In Fig. 3G, the valve is in its inserted position and in Fig. 3H, the installation tool 9 is pulled back in order to retract the arm 11. Subsequently, the tool string 8 is moved forward in the well so that the leak detection device is arranged opposite the valves to verify that the valve has been installed correctly and is working as intended and that it was in fact that valve that needed to be changed in order to solve the problem.
As can be seen in Fig. 3C, the retrieving tool 4 comprises a contact 50 for detecting a connection between the connector 7 and the valve 2. It is hereby ensured that attempts to replace a malfunctioning valve with a new valve do not result in the new valve being arranged on top of the unmoved malfunctioning valve.
In the valve changing system, the contact 50 may furthermore be in communication with an activation device 53 of the installation tool shown in Figs.
3E and 3F. This is to ensure that the installation tool is not activated until the installation tool has proper contact with the defect valve to be retrieved, and thus the installation of a functioning valve can be initiated. If the defect valve cannot be removed, the operation is abandoned without damaging the new valve.
The tool connection 39, as shown in Figs. 1 and 5, comprises a cylindrical tube having an internal thread corresponding to external threads of the retrieving and installation tools, or the tool connection 39 comprises latches hooking onto a corresponding groove or corresponding grooves in the retrieving and installation tools.
All the figures are highly schematic and not necessarily to scale, and they show only those parts which are necessary in order to elucidate the invention, other parts being omitted or merely suggested.
Detailed description of the invention Fig. 1 shows a valve changing system 1 for retrieving a valve 2 in a well 3 and installing another valve. The valve changing system 1 comprises a retrieving tool 4 for taking out the valve and an installation tool 9 for installing another valve.
The installation tool 9 is connected with the retrieving tool forming a tool string 8.
The tool string 8 is connected with a driving tool 13 for providing an axial movement in order to install or retrieve the valve. The valve changing system further comprises a leak detection device 14 for detecting temperature and/or acoustic variations. The leak detection device is arranged in one end of the tool string closest to the top of the well so that when the tools are moved forward in the well, the leak detection device can test the valves in the well. This end of the tool string comprises an electrical power device 20 powering a motor 15 which drives a pump 16. The pump 16 is part of the driving tool 13 providing the axial movement of the retrieving tool and the installation tool.
The tools are aligned along a tool string centre axis and the leak detection device is arranged substantially in line with the tool centre axis. By having the leak detection device in the end of the tool string, either in the end closest to the top of the well or in the opposite end in front of the tool string, the leak detection device can be arranged so that it is affected by any variations all around the interior of the casing. A leaking gas lift valve leaks bubbles into the well fluid and thus generates sound variations, and the gas most often has a temperature different from that of the well fluid, resulting in the gas leak also generating temperature variation. Furthermore, the gas expands in the fluid, resulting in an increased flow. The leak detection device arranged in front of or behind the tool string is not shielded and influenced by the tool string itself. If the leak detection device is arranged at one side of the tool housing, the leak detection device is not influenced by the variations at the opposite side of the housing since the tool housing shields for these variations. Thus, if the leak detection device is arranged on the side opposite to where the side pocket is located, the variations may not be detected and the defect valve may seem in order. The leak detection device arranged in front of the tool string or behind the tool string is equally affected by all variations along the circumference of the casing and is thus not shielded by the tool string. Hence, the leak detection device arranged at one end of the tool string is capable of detecting a gas leak and thus a defect valve even though such leak is positioned in a side pocket. Furthermore, the detection of the valve leaking and hence requiring replacement can be performed using only one fibre cable since it is arranged in line with the centre axis.
In Fig. 3A, the leak detection device 14 is arranged in front of one of the installation tool and the retrieving tool and in Figs. 1 and 2 the leak detection device 14 is arranged behind one of the installation tool and the retrieving tool closest to a well head of the well.
The leak detection device may be any kind of leak detection device such as a pressure sensor, a temperature sensor, a flow meter or an acoustic sensor, such as a microphone. A leaking gas lift valve leaks bubbles into the well fluid and thus generates sound variations, and the gas most often has a temperature different from that of the well fluid, resulting in the gas leak also generating temperature variation. Furthermore, the gas expands in the fluid, resulting in an increased flow. Thus, leak detection devices capable of sensing acoustic changes, temperature changes, pressure changes and/or flow changes can be suitable as a leak detection device.
In Fig. 1, the tool comprises a laser 51 for sending light pulses through the leak detection device 14 being a fibre optical cable sensor 14. A laser pulse is sent through the optical fibre of the fibre optical cable sensor and in the event of a leak, sound and perhaps also a temperature difference influence the optic fibre at that position by scattering the laser light. The intensity of the reflected light is measured as a function of time after transmission of the laser pulse of a detector 52 in the sensor 14. The reflected light at the position of the leak returns before the rest of the laser pulse has had time to travel the full length of the fibre and back, and thus the position of the leak and thus which gas lift valve is leaking can be determined.
The next laser pulse can be sent along the fibre when the previous laser pulse has travelled the full length and back. Changes in the reflected intensity of successive pulses from the same region of fibre opposite the leak are caused by changes in the optical path length of that section of fibre and confirm the position of the leak. This type of system is very sensitive to strain, noise and temperature variations of the fibre.
The retrieving tool comprises a housing 5 and an arm 6 pivotally connected with the housing. The arm has a connector 7 for connecting to the valve to be retrieved. The installation tool 9 also comprises a housing 10 and an arm 11 pivotally connected with the housing, and the arm has a connector 12 releasably connected to the new valve. The arms of the tools comprise two arm parts pivotally connected so that the first arm part is connected to the housing 10 and the second arm part is connected to the valve 2. Both the retrieving tool and the installation tool are a kind of kickover tool. The installation tool has a tool connection 39 arranged in an end opposite the driving tool transferring the axial movement of the driving tool to the retrieving tool so that only one driving tool is needed for movement of both arms of the tools. If the retrieving tool is arranged closest to the driving tool, the retrieving tool has a tool connection arranged in an end opposite the driving tool transferring the axial movement of the driving tool to the installation tool.
In Fig. 3A, the retrieving tool 4 is arranged opposite the valve 2 to be replaced.
In Fig. 3B, the arm 6 of the retrieving tool 4 is in its extended position, ready to be subjected to an axial movement from the driving tool 13 to engage the valve 2 by the connector of the arm 6. In Fig. 3C, the retrieving tool 4 has been 5 subjected to the axial movement and the arm 6 is connected to the valve 2, ready for retrieval. In Fig. 3D, the retrieving tool 4 is retrieving the valve 2 and the retrieving tool 4 is moved further down the well so that the installation tool 9 is arranged in the position opposite the opening 40 in which the valve is to be installed. In Fig. 3E, the arm 11 of the installation tool 9 is extended and the 10 valve is arranged opposite the opening 40 into which the valve is to be inserted.
In Fig. 3G, the valve is in its inserted position and in Fig. 3H, the installation tool 9 is pulled back in order to retract the arm 11. Subsequently, the tool string 8 is moved forward in the well so that the leak detection device is arranged opposite the valves to verify that the valve has been installed correctly and is working as intended and that it was in fact that valve that needed to be changed in order to solve the problem.
As can be seen in Fig. 3C, the retrieving tool 4 comprises a contact 50 for detecting a connection between the connector 7 and the valve 2. It is hereby ensured that attempts to replace a malfunctioning valve with a new valve do not result in the new valve being arranged on top of the unmoved malfunctioning valve.
In the valve changing system, the contact 50 may furthermore be in communication with an activation device 53 of the installation tool shown in Figs.
3E and 3F. This is to ensure that the installation tool is not activated until the installation tool has proper contact with the defect valve to be retrieved, and thus the installation of a functioning valve can be initiated. If the defect valve cannot be removed, the operation is abandoned without damaging the new valve.
The tool connection 39, as shown in Figs. 1 and 5, comprises a cylindrical tube having an internal thread corresponding to external threads of the retrieving and installation tools, or the tool connection 39 comprises latches hooking onto a corresponding groove or corresponding grooves in the retrieving and installation tools.
In Fig. 1, the driving tool is a downhole tractor which is also capable of driving the system forward in the well. Hereby, the valves in a horizontal part of the well can be tested in the same run as the valves in the vertical part of the well.
The driving tool comprises wheels arranged on a wheel arm and has an electrical motor 15 driving a pump 16 which drives the wheel to move the system forward in the well. The wheels thus provide the axial movement needed for retrieving or installing a valve. The arm of the retrieving and installation tool is extending when a latch of the tool hooks onto a trail 25 or groove in the vicinity of the valve and is thus pulled back again by means of the trail 25.
In Fig. 2, the driving tool is a stroking tool which comprises a motor 15 and a pump 16 driven by the motor. The pump pumps fluid into a piston chamber 17 in the stroking tool moving a piston 18 connected with a piston shaft 19, the shaft being connected with the retrieving tool or installation tool for transferring the axial movement. In order to transfer the axial movement to the retrieving or installation tool, the valve changing system 1 comprises an anchoring section which is activated by the pump before providing the stroking movement.
The piston 18 divides the piston chamber of the stroking tool into a first chamber part 22 and a second chamber part 23, and the pump pumps fluid into the first chamber part and sucks fluid out of the second chamber part. In another embodiment, the stroking tool comprises several pistons, each piston being arranged in a piston chamber 17 providing greater axial force than one piston as the pump pumps fluid into every first chamber parts to apply pressure on the piston from one side and to pull from the other side by pumping fluid out of the second chamber part. In order to pull the retrieving or installation tool back, the pump pumps fluid into the second chamber parts and pumps fluid out of the first chamber parts.
The fibre optical cable sensor 14 is a distribution acoustic sensor. The fibre optical cable sensor comprises a single mode fibre operating at a wavelength of 1000 nm-2000 nm, preferably at a wavelength of 1200 nm-1800 nm, and more preferably at a wavelength of 1400 nm-1600 nm, such as at a wavelength of 1550 nm. The fibre optical cable sensor operates at an attenuation of 0.1-0.3 dB/km.
The driving tool comprises wheels arranged on a wheel arm and has an electrical motor 15 driving a pump 16 which drives the wheel to move the system forward in the well. The wheels thus provide the axial movement needed for retrieving or installing a valve. The arm of the retrieving and installation tool is extending when a latch of the tool hooks onto a trail 25 or groove in the vicinity of the valve and is thus pulled back again by means of the trail 25.
In Fig. 2, the driving tool is a stroking tool which comprises a motor 15 and a pump 16 driven by the motor. The pump pumps fluid into a piston chamber 17 in the stroking tool moving a piston 18 connected with a piston shaft 19, the shaft being connected with the retrieving tool or installation tool for transferring the axial movement. In order to transfer the axial movement to the retrieving or installation tool, the valve changing system 1 comprises an anchoring section which is activated by the pump before providing the stroking movement.
The piston 18 divides the piston chamber of the stroking tool into a first chamber part 22 and a second chamber part 23, and the pump pumps fluid into the first chamber part and sucks fluid out of the second chamber part. In another embodiment, the stroking tool comprises several pistons, each piston being arranged in a piston chamber 17 providing greater axial force than one piston as the pump pumps fluid into every first chamber parts to apply pressure on the piston from one side and to pull from the other side by pumping fluid out of the second chamber part. In order to pull the retrieving or installation tool back, the pump pumps fluid into the second chamber parts and pumps fluid out of the first chamber parts.
The fibre optical cable sensor 14 is a distribution acoustic sensor. The fibre optical cable sensor comprises a single mode fibre operating at a wavelength of 1000 nm-2000 nm, preferably at a wavelength of 1200 nm-1800 nm, and more preferably at a wavelength of 1400 nm-1600 nm, such as at a wavelength of 1550 nm. The fibre optical cable sensor operates at an attenuation of 0.1-0.3 dB/km.
The leak detection device may furthermore comprise a distribution temperature sensor. The valve changing system is moved back and forth in the well so that the leak detection device is located opposite each of the valves in order to detect which valve is leaking or stuck.
In Fig. 4, the fibre optical cable sensor is part of a wireline, e-line or slickline connected to the tool string 8 in order to retrieve the tool string. The wires 26 are arranged on the outside and the optical fibre 14 on the inside. The wireline may also comprise electrical cables 27 as illustrated in Fig. 4.
In Fig. 5, the valve changing system 1 has the retrieving tool 4, the installation tool 9, the leak detection device 14 and two driving tools 13 in the form of a stroking tool and a downhole tractor. The stroking tool provides the axial force to replace the valve and the downhole tractor drives the valve changing system 1 back and forth in the well so as to move the valve changing system 1 into a specific position to perform a certain operation.
The valve changing system 1 is thus used to determine if a valve needs to be replaced or which valve needs to be replaced, to replace the valve and verify that the valve has been correctly installed and functions as intended.
If the well only has one gas lift valve and production is not running, the valve changing system is entered into the well and the valve changing system is moved to a position in which the retrieving tool is opposite at least one valve in the well.
Subsequently, the valve is retrieved by means of the retrieving tool, and the valve changing system is moved so that the installation tool is in the position opposite the opening in which the valve is to be installed and the installation tool installs another valve by means of the installation tool, and then the valve changing system is moved backwards so that the leak detection device passes the installed valve and detects the temperature and/or acoustic variations opposite the at least one valve by means of the fibre optical cable sensor. If the valve is functioning perfectly, the valve changing system is pulled out of the well.
If e.g. a dummy valve is leaking and the well has been closed, the leak detection device 14 is able to detect the flow around the valve by means of acoustic sensing. When the gas lift valve is functioning, the leak detection device 14 is able to detect the gas flowing in by means of acoustic sensing. Temperature sensing is another way of detecting flow as the temperature will change locally.
When having several valves in the well, the defect valve needs to be located.
After lowering the system into the well, the valve changing system is moved so that the leak detection device 14 passes a plurality of valves in order to detect which valve is defect, and then the valve changing system is moved to a position so that the retrieving tool is opposite the defect valve, the defect valve is retrieved by means of the retrieving tool, and then the valve changing system is moved again so that the installation tool is in the position, and another valve is installed by means of the installation tool. Subsequently, the valve changing system 1 is moved back and forth so that the leak detection device 14 passes the installed valve 2 and detects any temperature and/or acoustic variations opposite the at least one valve by means of the leak detection device 14. By having such system, the detection of which valve to replace, the replacement operation and the verification step can be performed in one run instead of in many runs as is the case when using prior art tools.
The invention further relates to the valve changing method for changing a valve in a well by entering the aforementioned valve changing system into the well for detecting which valve of a plurality of valves is leaking by moving the valve changing system so that the leak detection device 14 passes all the valves 2 in order to detect which valve is defect. When the leaking valve is located, the valve changing system is moved to the position so that the retrieving tool is opposite the defect valve, and then the connector 7 of the retrieving tool connects with the defect valve by moving the arm of the retrieving tool. When the defect valve has been removed by retracting the arm, the valve changing system is moved so that the installation tool is in the position and the new valve is installed by means of the arm of the installation tool.
The invention further relates to the valve changing method for changing a valve in a well by entering the aforementioned valve changing system into the well for detecting if the valve is leaking by moving the valve changing system. The valve changing system is moved so that the leak detection device passes the installed valve and detects temperature and/or acoustic variations opposite the at least one valve by means of the fibre optical cable sensor. If the valve is defect, the valve changing system is moved to a position in which the retrieving tool is opposite at least one valve in the well and the defect valve is removed. Then the installation tool is moved opposite the position for installing another valve.
When the defect valve has been replaced, the valve changing system verifies that the valve is functioning. The system is moved so that the leak detection device passes the installed valve and the leak detection device detects acoustic variations or even temperature variation opposite the at least one valve by means of the leak detection device. The verification may be performed in two steps. First, the valve is in its closed position and the leak detection device 14 is moved past to verify that the valve is installed correctly in that the leak detection device 14 senses no variations opposite the newly installed valve apart from the normal variations in the well. Second, the valve is set in its operation mode so that gas is let in through the valve and the leak detection device 14 is moved past to verify that sound variations is detected opposite the valve.
In one embodiment, the step of detecting acoustic variations by the fibre optical cable sensor is performed using Rayleigh scatter based sensing as known by a person skilled in the art. The laser thus sends coherent laser light pulse along the fibre optical cable sensor and the intensity of the reflected laser light as a function of time after transmission of the laser pulse is detected in the detector and a position of the defect valve is determined.
The system may further comprise an adjustment device for adjusting the installed valve to be more open or closed. In order to determine if the valve is leaking, the well may be closed while conducting an acoustic detection by means of the leak detection device.
By fluid or well fluid is meant any kind of fluid that may be present in oil or gas wells downhole, such as natural gas, oil, oil mud, crude oil, water, etc. By gas is meant any kind of gas composition present in a well, completion, or open hole, and by oil is meant any kind of oil composition, such as crude oil, an oil-containing fluid, etc. Gas, oil, and water fluids may thus all comprise other elements or substances than gas, oil, and/or water, respectively.
By a casing is meant any kind of pipe, tubing, tubular, liner, string etc.
used downhole in relation to oil or natural gas production.
In the event that the tool is not submergible all the way into the casing, a downhole tractor can be used to push the tool all the way into position in the well. A downhole tractor is any kind of driving tool capable of pushing or pulling tools in a well downhole, such as a Well Tractor .
Although the invention has been described in the above in connection with preferred embodiments of the invention, it will be evident for a person skilled in the art that several modifications are conceivable without departing from the invention as defined by the following claims.
In Fig. 4, the fibre optical cable sensor is part of a wireline, e-line or slickline connected to the tool string 8 in order to retrieve the tool string. The wires 26 are arranged on the outside and the optical fibre 14 on the inside. The wireline may also comprise electrical cables 27 as illustrated in Fig. 4.
In Fig. 5, the valve changing system 1 has the retrieving tool 4, the installation tool 9, the leak detection device 14 and two driving tools 13 in the form of a stroking tool and a downhole tractor. The stroking tool provides the axial force to replace the valve and the downhole tractor drives the valve changing system 1 back and forth in the well so as to move the valve changing system 1 into a specific position to perform a certain operation.
The valve changing system 1 is thus used to determine if a valve needs to be replaced or which valve needs to be replaced, to replace the valve and verify that the valve has been correctly installed and functions as intended.
If the well only has one gas lift valve and production is not running, the valve changing system is entered into the well and the valve changing system is moved to a position in which the retrieving tool is opposite at least one valve in the well.
Subsequently, the valve is retrieved by means of the retrieving tool, and the valve changing system is moved so that the installation tool is in the position opposite the opening in which the valve is to be installed and the installation tool installs another valve by means of the installation tool, and then the valve changing system is moved backwards so that the leak detection device passes the installed valve and detects the temperature and/or acoustic variations opposite the at least one valve by means of the fibre optical cable sensor. If the valve is functioning perfectly, the valve changing system is pulled out of the well.
If e.g. a dummy valve is leaking and the well has been closed, the leak detection device 14 is able to detect the flow around the valve by means of acoustic sensing. When the gas lift valve is functioning, the leak detection device 14 is able to detect the gas flowing in by means of acoustic sensing. Temperature sensing is another way of detecting flow as the temperature will change locally.
When having several valves in the well, the defect valve needs to be located.
After lowering the system into the well, the valve changing system is moved so that the leak detection device 14 passes a plurality of valves in order to detect which valve is defect, and then the valve changing system is moved to a position so that the retrieving tool is opposite the defect valve, the defect valve is retrieved by means of the retrieving tool, and then the valve changing system is moved again so that the installation tool is in the position, and another valve is installed by means of the installation tool. Subsequently, the valve changing system 1 is moved back and forth so that the leak detection device 14 passes the installed valve 2 and detects any temperature and/or acoustic variations opposite the at least one valve by means of the leak detection device 14. By having such system, the detection of which valve to replace, the replacement operation and the verification step can be performed in one run instead of in many runs as is the case when using prior art tools.
The invention further relates to the valve changing method for changing a valve in a well by entering the aforementioned valve changing system into the well for detecting which valve of a plurality of valves is leaking by moving the valve changing system so that the leak detection device 14 passes all the valves 2 in order to detect which valve is defect. When the leaking valve is located, the valve changing system is moved to the position so that the retrieving tool is opposite the defect valve, and then the connector 7 of the retrieving tool connects with the defect valve by moving the arm of the retrieving tool. When the defect valve has been removed by retracting the arm, the valve changing system is moved so that the installation tool is in the position and the new valve is installed by means of the arm of the installation tool.
The invention further relates to the valve changing method for changing a valve in a well by entering the aforementioned valve changing system into the well for detecting if the valve is leaking by moving the valve changing system. The valve changing system is moved so that the leak detection device passes the installed valve and detects temperature and/or acoustic variations opposite the at least one valve by means of the fibre optical cable sensor. If the valve is defect, the valve changing system is moved to a position in which the retrieving tool is opposite at least one valve in the well and the defect valve is removed. Then the installation tool is moved opposite the position for installing another valve.
When the defect valve has been replaced, the valve changing system verifies that the valve is functioning. The system is moved so that the leak detection device passes the installed valve and the leak detection device detects acoustic variations or even temperature variation opposite the at least one valve by means of the leak detection device. The verification may be performed in two steps. First, the valve is in its closed position and the leak detection device 14 is moved past to verify that the valve is installed correctly in that the leak detection device 14 senses no variations opposite the newly installed valve apart from the normal variations in the well. Second, the valve is set in its operation mode so that gas is let in through the valve and the leak detection device 14 is moved past to verify that sound variations is detected opposite the valve.
In one embodiment, the step of detecting acoustic variations by the fibre optical cable sensor is performed using Rayleigh scatter based sensing as known by a person skilled in the art. The laser thus sends coherent laser light pulse along the fibre optical cable sensor and the intensity of the reflected laser light as a function of time after transmission of the laser pulse is detected in the detector and a position of the defect valve is determined.
The system may further comprise an adjustment device for adjusting the installed valve to be more open or closed. In order to determine if the valve is leaking, the well may be closed while conducting an acoustic detection by means of the leak detection device.
By fluid or well fluid is meant any kind of fluid that may be present in oil or gas wells downhole, such as natural gas, oil, oil mud, crude oil, water, etc. By gas is meant any kind of gas composition present in a well, completion, or open hole, and by oil is meant any kind of oil composition, such as crude oil, an oil-containing fluid, etc. Gas, oil, and water fluids may thus all comprise other elements or substances than gas, oil, and/or water, respectively.
By a casing is meant any kind of pipe, tubing, tubular, liner, string etc.
used downhole in relation to oil or natural gas production.
In the event that the tool is not submergible all the way into the casing, a downhole tractor can be used to push the tool all the way into position in the well. A downhole tractor is any kind of driving tool capable of pushing or pulling tools in a well downhole, such as a Well Tractor .
Although the invention has been described in the above in connection with preferred embodiments of the invention, it will be evident for a person skilled in the art that several modifications are conceivable without departing from the invention as defined by the following claims.
Claims (28)
1. A valve changing system (1) for retrieving and installing a valve (2) in a well (3), comprising - a tool string comprising:
- a retrieving tool (4) for taking out the valve, comprising a housing (5) and an arm (6) pivotally connected with the housing, said arm having a connector (7) for connection to the valve, and - an installation tool (9) for installing another valve connected with the retrieving tool forming a tool string (8), the installation tool comprising a housing (10) and an arm (11) which is pivotally connected with the housing and has a connector (12) for connection to another valve, - a driving tool (13) connected with the installation tool and the retrieving tool for providing an axial movement In order to install or retrieve the valve, and - a leak detection device (14) for detecting temperature and/or acoustic variations, the leak detection device being arranged In one end of the tool string, wherein the driving tool comprises a stroking tool comprising a motor (15) and a pump (16) driven by the motor, the pump pumping fluid into a piston chamber (17) in the stroking tool moving a piston (18) connected with a piston shaft (19), said shaft being connected with the retrieving tool or installation tool for transferring the axial movement.
- a retrieving tool (4) for taking out the valve, comprising a housing (5) and an arm (6) pivotally connected with the housing, said arm having a connector (7) for connection to the valve, and - an installation tool (9) for installing another valve connected with the retrieving tool forming a tool string (8), the installation tool comprising a housing (10) and an arm (11) which is pivotally connected with the housing and has a connector (12) for connection to another valve, - a driving tool (13) connected with the installation tool and the retrieving tool for providing an axial movement In order to install or retrieve the valve, and - a leak detection device (14) for detecting temperature and/or acoustic variations, the leak detection device being arranged In one end of the tool string, wherein the driving tool comprises a stroking tool comprising a motor (15) and a pump (16) driven by the motor, the pump pumping fluid into a piston chamber (17) in the stroking tool moving a piston (18) connected with a piston shaft (19), said shaft being connected with the retrieving tool or installation tool for transferring the axial movement.
2. A valve changing system according to claim 1, wherein the leak detection device is a pressure sensor, a temperature sensor, a flow meter or an acoustic sensor, such as a microphone:
3. A valve changing system according to claim 1 or 2, wherein the tools are aligned along a tool string centre axis and the leak detection device is arranged substantially in line with the tool centre axis.
4. A valve changing system according to any of the preceding claims, wherein the leak detection device is arranged in front of one of the Installation tool and the retrieving tool or arranged behind one of the installation tool and the retrieving tool closest to a well head of the well.
5. A valve changing system according to any of the preceding claims, wherein the leak detection device Is a fibre optical cable sensor.
6. A valve changing system according to claim 5, wherein the fibre optical cable sensor comprises a single mode fibre operating at a wavelength of 1000 nm-2000 nm, preferably at a wavelength of 1200 nm-1800 nm, and more preferably at a wavelength of 1400 nm-1600 nm, such as at a wavelength of 1550 nm.
7. A valve changing system according to claim 5 or 6, wherein the fibre optical cable sensor operates at an attenuation of 0.1-0.3 dB/km.
8. A valve changing system according to any or preceding claims, further comprising a wireline (21) for powering the tools.
9. A valve changing system according to claim 8, wherein the leak detection device is a fibre optical cable sensor being part of a wireline, an e-line or a slickline connected to the tool string in order to retrieve the tool string.
10, A valve changing system according to any of claims 5-9, wherein the fibre optical cable sensor is a distribution temperature sensor and/or a distribution acoustic sensor,
11. A valve changing system according to any claims 5-10, wherein the tool comprises a laser for sending light pulses through the fibre optical cable sensor.
12. A valve changing system according to claim 11, wherein the tool comprises a detector for detecting the intensity of the reflected light pulses.
13. A valve changing system according to any of the preceding claims, wherein the retrieving tool further comprises a contact (50) for detecting a connection between the connector (7) and the valve.
14. A valve changing system according to claim 13, wherein the contact is in communication with an activation device of the installation tool.
15. A valve changing system according to any of the preceding claims, wherein the driving tool comprises a downhole tractor, said driving tool also being capable of driving the system forward in the well.
16. A valve changing system according to claim 15, wherein the driving tool comprises wheels arranged on a wheel arm and has an electrical motor (15) driving a pump (16) which drives the wheel to move the system forward in the well.
17. A valve changing system according to any of the preceding claims, wherein the driving tool comprises an electrical power device (20) to power the tools.
18. A valve changing system according to claim 1, wherein the piston divides the piston chamber of the stroking tool into a first chamber part (22) and a second chamber part (23), and the pump pumps fluid Into the first chamber part and sucks fluid out of the second chamber part.
19. A valve changing system according to any of claims 1 or 18, wherein the stroking tool comprises several pistons, each piston being arranged in a piston chamber,
20. A valve changing system according to any of the preceding claims, further comprising an anchoring section (24).
21. A valve changing method for changing a valve in a well, comprising the steps of:
- entering the valve changing system according to any of claims 1-20, - moving the valve changing system so that the leak detection device passes a plurality of valves in order to detect which valve is defect, - moving the valve changing system to a position so that the retrieving tool is opposite the defect valve, - retrieving the defect valve by means of the retrieving tool, - moving the valve changing system so that the installation tool is In the position, and - installing another valve by means of the installation tool.
- entering the valve changing system according to any of claims 1-20, - moving the valve changing system so that the leak detection device passes a plurality of valves in order to detect which valve is defect, - moving the valve changing system to a position so that the retrieving tool is opposite the defect valve, - retrieving the defect valve by means of the retrieving tool, - moving the valve changing system so that the installation tool is In the position, and - installing another valve by means of the installation tool.
22. A valve changing method according to claim 21, further comprising the step of moving the valve changing system so that the leak detection device passes the Installed valve, and detecting temperature and/or acoustic variations opposite the at least one valve by means of the leak detection device.
23. A valve changing method comprising the steps of:
- entering the valve changing system according to any of claims 1-20, - moving the valve changing system to a position in which the retrieving tool is opposite at least one valve in the well, - retrieving the valve by means of the retrieving tool, - moving the valve changing system so that the installation tool is In the position, - Installing another valve by means of the installation tool, - moving the valve changing system so that the leak detection device passes the installed valve, and - detecting temperature and/or acoustic variations opposite the at least one valve by means of the leak detection device.
- entering the valve changing system according to any of claims 1-20, - moving the valve changing system to a position in which the retrieving tool is opposite at least one valve in the well, - retrieving the valve by means of the retrieving tool, - moving the valve changing system so that the installation tool is In the position, - Installing another valve by means of the installation tool, - moving the valve changing system so that the leak detection device passes the installed valve, and - detecting temperature and/or acoustic variations opposite the at least one valve by means of the leak detection device.
24. A valve changing method according to any of claims 21-23, wherein the leak detection device is a fibre optical sensor and the step of detecting acoustic variations Is performed using Rayleigh scatter based sensing.
25. A valve changing method according to any of claims 21-24, further comprising the step of sending a coherent laser light pulse along the leak detection device being a fibre optical cable sensor.
26. A valve changing method according to any of claims 21-25, further comprising the step of measuring of the intensity of the reflected laser light as a function of time after transmission of the laser pulse.
27. A valve changing method according to claim 21 or 26, further comprising the step of adjusting the installed valve to be more open or closed.
28. A valve changing method according to any of claims 21-27, further comprising the step of closing the well while conducting an acoustic detection by means of the leak detection device.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP11172157A EP2540955A1 (en) | 2011-06-30 | 2011-06-30 | Gas lift kickover system |
| EP11172157.7 | 2011-06-30 | ||
| PCT/EP2012/062698 WO2013001062A1 (en) | 2011-06-30 | 2012-06-29 | Gas lift kickover system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2840463A1 true CA2840463A1 (en) | 2013-01-03 |
Family
ID=46397286
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2840463A Abandoned CA2840463A1 (en) | 2011-06-30 | 2012-06-29 | Gas lift kickover system |
Country Status (7)
| Country | Link |
|---|---|
| EP (2) | EP2540955A1 (en) |
| CN (1) | CN103649453A (en) |
| AU (1) | AU2012277781A1 (en) |
| BR (1) | BR112013032672A2 (en) |
| CA (1) | CA2840463A1 (en) |
| MX (1) | MX2013014575A (en) |
| WO (1) | WO2013001062A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2886790A1 (en) * | 2013-12-18 | 2015-06-24 | Welltec A/S | Downhole deployment system for ejecting a tracer and/or taking a fluid sample |
| AR127268A1 (en) * | 2021-10-08 | 2024-01-03 | Impact Selector Int Llc | KICKOVER TOOL |
| CN115162985B (en) * | 2022-06-15 | 2023-06-13 | 四川大学 | Deep in-situ fidelity core calibration platform safety monitoring system |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4703459A (en) * | 1984-12-03 | 1987-10-27 | Exxon Production Research Company | Directional acoustic logger apparatus and method |
| US6955218B2 (en) * | 2003-08-15 | 2005-10-18 | Weatherford/Lamb, Inc. | Placing fiber optic sensor line |
| WO2007003445A1 (en) * | 2005-02-03 | 2007-01-11 | Philip Head | Sensor system for gas lift wells |
| US7451810B2 (en) * | 2006-05-18 | 2008-11-18 | Schlumberger Technology Corporation | Kickover tool and selective mandrel system |
| US7967075B2 (en) * | 2007-08-31 | 2011-06-28 | Schlumberger Technology Corporation | High angle water flood kickover tool |
| EP2208039B1 (en) * | 2007-10-10 | 2015-09-02 | Tecwel AS | Method and system for registering and measuring leaks and flows |
| NO333413B1 (en) * | 2009-12-07 | 2013-06-03 | Petroleum Technology Co As | Downhole estimation tool |
-
2011
- 2011-06-30 EP EP11172157A patent/EP2540955A1/en not_active Withdrawn
-
2012
- 2012-06-29 CN CN201280032180.0A patent/CN103649453A/en active Pending
- 2012-06-29 BR BR112013032672A patent/BR112013032672A2/en not_active IP Right Cessation
- 2012-06-29 WO PCT/EP2012/062698 patent/WO2013001062A1/en active Application Filing
- 2012-06-29 EP EP12730560.5A patent/EP2780535A1/en not_active Withdrawn
- 2012-06-29 MX MX2013014575A patent/MX2013014575A/en unknown
- 2012-06-29 CA CA2840463A patent/CA2840463A1/en not_active Abandoned
- 2012-06-29 AU AU2012277781A patent/AU2012277781A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| WO2013001062A1 (en) | 2013-01-03 |
| MX2013014575A (en) | 2014-03-21 |
| AU2012277781A1 (en) | 2013-05-02 |
| EP2780535A1 (en) | 2014-09-24 |
| EP2540955A1 (en) | 2013-01-02 |
| BR112013032672A2 (en) | 2017-01-24 |
| CN103649453A (en) | 2014-03-19 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |
Effective date: 20150630 |