The field of this invention comprises methods of allowing the provision of conduits which can carry the power, signal, hydraulic, pressure, fiber optic cable, and other means of communication down to a bottom hole assembly where the completion requires multiple trips.
In certain types of completions, a bottom assembly such as, for example, gravel pack screens are assembled as part of the liner and a liner top packer and installed in the well bore. Various operations thereafter occur involving specialized equipment. For example, cementing the liner and gravel packing the screens. After the completion of such steps with specialized equipment, the production string is then tagged into the liner-top packer so that production can begin. Due to the multi-stage nature of such operations, prior techniques for mounting auxiliary conduits to the assembly as it is put together at the surface were not workable. For example, in completions where the liner, liner top packer, and production tubing are inserted in a single trip, the auxiliary conduits can be assembled to the liner and production tubing as the assembly is being put together at the surface. With these types of single step installations, the auxiliary conduits could be extended to the desired location without the need to disassemble the auxiliary conduits because subsequent trips would be required for different specialized tools.
As previously stated, where the completion requires multiple steps and trips into the well bore, if auxiliary conduits are to be provided to the producing zone, techniques in the past have not been developed to allow that to occur.
More recently a technique has been developed which is subject to a co-pending patent application which is literally repeated as part of this specification, a technique has been developed to allow auxiliary conduits to be sealingly connected to each other down hole. The availability of this development, to solve a different problem, has opened up a possibility of allowing auxiliary conduits to run down to the producing formations adjacent to the bottom hole assembly. The method of this invention is a procedure whereby such auxiliary conduits can be used in conjunction with a variety of down hole operations such as, for example, gravel pack screens. The auxiliary conduits can be used for a variety of purposes such as actuation of down hole flow control devices, chemical injection, actuation of down hole proppant/chemical injection placement valves, distributed temperature data through fiber optic lines, the disposition of discrete sensors whether electric or fiber, pressure measurements, fluid characterization, and flow rate measurements to name a few. The auxiliary conduits can also be used in the gravel packing operation itself. Stated differently, the method of the present invention allows real time feed back of down hole conditions as certain completion operations are undertaken as well as the ability to sense the formation conditions during production. Accordingly, through the use of fiber optics, one of the objectives of the invention is to sense a variety of data at different times, for example, in a gravel pack completion. The fiber optic cables can be used to sense through pressure impacting them the distribution of the gravel during the gravel packing operation. It can also detect changes in the formation down below during production. Thus, another objective of the invention through the incorporation of the fiber optic technology is to be able to take measurements such as density, impaction, and other physical characteristics of a gravel pack through the use of electrical or fiber optic sensors integrated with screens located in the gravel pack itself. Some of the variables that can be measured with the technique are strain temperature, vibration, pressure, and density to name a few.
Accordingly, it is the objective of the present invention to provide a method whereby auxiliary conduits can be instrumental in the performance of various operations essential to the completion as well as to provide data on a real-time basis of down hole conditions during production particularly in multi-step completion involving multiple trips into the well bore where prior techniques have not allowed auxiliary conduits to extend to the producing zones below a liner top packer, for example.
The following U.S. Patents relate to down hole sensing and also include the use of fiber optics as the sensing devices: U.S. Pat. Nos. 5,925,879; 5,804,713; 5,875,852; 5,892,860; 5,767,411; 5,892,176; 5,723,781; 5,789,662; 5,667,023; 5,579,842; 5,577,559; 5,582,064; 5,570,437; 5,443,119; 5,410,152; 5,386,875; 5,360,066; 5,309,405; 5,252,832; 4,919,201; and 4,783,995.
These patents generally relate to the need to measure parameters in the producing zones of oil, gas, and injection wells. The measurements are used to trace production flow, validate performance of the producing zones, and the equipment installed in those zones, and to optimize production. However, in situations involving multi-trip operations such as a gravel packing a well, such access was unavailable in the previously known devices. In some instances to compensate for this lack of ability to sense in the producing zone, production logging tools or memory logging tools were used. However, running these tools required interruption of production. While these tools provided data, it was only discrete snapshots of the production environment and such information was often provided at a significant direct and indirect cost. Accordingly, one of the objects of the present invention is to provide continuous on demand data to evaluate the performance and health of a well. This is particularly more critical in situations where the completion is complicated as is often used for horizontal and multi-lateral wells.
In the past companies such as Sensor Highway and Pruitt Industries have used control tubes as a means of deploying optical fiber as a distributed temperature sensor, DTS. A pump-down technique has been developed to deploy fiber optic cables in the control tubes. This technique is illustrated in U.S. Pat. No. 5,570,437.
Those skilled in the art will appreciate the scope of the method of the present invention by a description of the preferred embodiment which appears below.
A technique for providing auxiliary conduits in multi-trip completions is disclosed. The technique has particular applicability to liner mounted screens which are to be gravel packed. In the preferred embodiment, a protective shroud is run with the gravel pack screens with the auxiliary conduits disposed in between. The auxiliary conduits terminate in a quick connection at a liner top packer. The gravel packing equipment can optionally be secured in a flow relationship to the auxiliary conduits so as to control the gravel packing operation. Subsequent to the removal of the specialized equipment, the production tubing can be run with an auxiliary conduit or conduits for connection down hole to the auxiliary conduits coming from the liner top packer for a sealing connection. Thereafter, during production various data on the well can be obtained in real time despite the multiple trips necessary to accomplish completion. The various activities can also be accomplished using the auxiliary conduits such as actuation of down hole flow control devices, chemical injection, pressure measurement, distributed temperature sensing through fiber optics, as well as other down hole parameters.
a–c are a sectional elevational view of the outer or lower portion of the connector with the running tool inserted therein;
a–c show both portions of the connector in sectional elevation connected to each other;
a–d show a passage around a packer in sectional elevational view, indicating the path of the control line around the packer sealing and gripping assemblies;
a is an elevational view including two sections showing the quick connection between the shroud and tubular.
The preferred embodiment of the method of the present invention relates to the ability to place auxiliary conduits or/and fiber optics near gravel pack screens. Those skilled in the art will appreciate that other applications for auxiliary conduits adjacent the producing formation are within the scope of this invention. Most applicable are multi-trip completion procedures where there is still a need for real time communication to the surface from the zone where the completion is taking place or where ultimately the production continues, or below.
In the preferred embodiment, a shroud assembly 200 shown in
Those skilled in the art will appreciate that when the shroud assembly 200 is employed, it is assembled and supported from the rotary table. The screen assembly 210 is assembled into the shroud assembly 200 and they are joined at quick coupling 222, which is a known design. Referring to
Those skilled in the art will appreciate after the packer 220 is set, multiple trips are generally required to finish the gravel packing operation, using standard equipment and known techniques. The individual conduits provided by this invention can be utilized in the same manner on each of the successive trips or they may be used in differing manners depending on the requirements and equipment utilized during the completion and production phases of the well bore. The method of the present invention, however, allows the opportunity for communication through conduits such as 212 which can include the placement of fiber optics in the vicinity of the screens 214 and the communication of the data to the surface from the vicinity of the screen through signals of conditions sent through the fiber optic network surrounding the screens 214, in the various embodiments as will be described below in
As shown in
As shown in
The ability to provide one or more conduits down to the producing zone in a completion which requires multiple trips in the well provides numerous benefits. It allows verification and optimization of the performance of a gravel pack completion. It allows a means to continuously monitor the performance of a gravel pack while the reservoir is being produced. The sensors shown schematically as “S” in
Depending on the size of the down hole equipment, five or more isolated conduits such as 212 can be provided. The nature of the down hole equipment can be diverse as discrete sensors or optical fibers can be used in different conduits 212 which obtain different types of data from a variety of locations at the same time and on a real-time basis. The shroud assembly 200 provides protection for the conduits 212 or the exposed fibers such as illustrated in
Those skilled in the art will appreciate that the method of the present invention allows sensing of the early arrival of undesired fluid such as water, flash gas, into the log well bores, particularly in the horizontal well bore application. One of the disadvantages of known intelligent well systems and other monitoring systems involves costly on-the-fly joy stick control. However, since accurate monitoring is the overwhelming majority of the information needed for effective well control, the method of the present invention allows knowledge of what the well is doing at any given time and, therefore, allows for other remedial action such as optimized flow rate, altered water injections schemes, and other surface adjustments. Using on-off type methodology as opposed to sophisticated linear control, presents a simpler and more economical solution to the problem particularly in multi-trip completions.
The method of the present invention allows active monitoring of the quality of gravel pack both during gravel packing operations and throughout the life of the oil well. The technique is to measure density, compaction and other physical characteristics of the gravel pack through the use of electrical or fiber optic sensors that are integrated with the screen or located in the gravel pack itself. Typical parameters to be monitored include but are not limited to strain, temperature, vibration, pressure and density. In one embodiment, the optical fibers can be combined with strain sensors attached to the circumference of the sand control equipment in a configuration or pattern determined by the measurement density desired. Placement of sensors can provide full radius coverage generating a 360° stress profile where desired. The sensors can be installed to measure the changes and stresses of the screen or components of the screen during the gravel packing operation so as to track the progress and quality of the gravel pack. During production, the pressure applied to the screen and/or its outerjacket, if any, will be measured and localized as stress along the length of the circumference of the screen. This provides the operator with information on how the flow into the screen is progressing and also provides information as to the integrity of the well bore. Location and flow rate into the screen or shroud can be characterized both along the length of the tools and circumferentially by virtue of real time monitoring of the applied stresses. The integrity of the well bore can be measured by monitoring the value and location of the stresses applied to the screen or protective shroud due to partial or complete collapse of the well bore cavity. As shown in
A variation of this method would be to only loosely couple the fiber in the encapsulating tubing so as no external strain is transmitted to the fiber. As the tubing or drill stem is deployed into the well bore, very long lengths of the tubing could be automatically swedged onto the outside of the drill stem or tubing to provide a connector free fiber optic path to downhole devices such as motors, LWD, MWD, and gravel packers. When the drill stem or tubing is retrieved from the well bore, the communication tubing could be automatically removed from the tubing and stored for later reuse.
The optical strain sensor system with or without temperature compensation can incorporate one or multiple optical fibers with discreet sensors, one or multiple optical fibers with more than one optical strain sensor multiplexed into each fiber or one or multiple distributed strain sensors in which the strain of the fiber is measured directly in the fiber.
The electrical embodiment of the system is to substitute and/or combine the electrical sensors and systems for the fiber optic systems in the above embodiments to monitor the completion and operation of the sand control equipment.
In yet another embodiment of the method of the present invention, the fibers can be inserted into helical inlet channels used in conjunction with gravel pack screens to optimize production and delay water or gas coning in long, low-drawdown, high-rate horizontal wells. This product sold by Baker Hughes under the name Equalizer™ has in each segment of gravel pack screen an inlet helix. With fiber optics disposed in such a helix, the ability to sense differing densities in the flowing stream can be used to determine the composition of the inflowing stream into its separate gas or liquid components. The screen component just described is illustrated in
The nature of the quick coupling 22 will now be described.
Referring to
The running tool R is made up of a top sub 14, which is connected to a sleeve 16 at thread 18. Sleeve 16 is connected to sleeve 20 at thread 22. Sleeve 22 is connected to bottom sub 24 at thread 26. Bottom sub 24 has a bottom passage 28, as well as a ball seat assembly 30. The ball seat assembly 30 is held to the bottom sub 24 by shear pin or pins 32. Although a shear pin or pins 32 are shown, other types of breakable members can be employed without departing from the spirit of the invention. The ball seat assembly 30 has a tapered seat 34 to accept a ball 36 to build pressure in internal passage 38. Bottom sub 24 also has a lateral port 40 which, in the position shown in
The running tool R also has a groove 54 to accept a dog 56 which is held in place by assembly of retaining cap 58, as will be described below. When retaining cap 58 is secured to orientation sub 46 at thread 60, with dog 56 in place in groove 54, the running tool R is locked in position with respect to orientation sub 46.
Looking further down the running tool R as shown in
The lower body L includes a tubular housing 72 which, as previously stated, has a lower end 12 with a thread 10 for connection of the bottomhole assembly. In the preferred embodiment, a pair of control lines, only one of which 74 is shown, run longitudinally along the length of the tubular housing 72. The control line 74 terminates at an upper end 76 with a receptacle 78. In order to make the control line connection, the control line 74 becomes a passage 80 prior to the termination of passage 80 in the receptacle 78. Passage 80 is shown in alignment with passage 48. This occurs because when the running tool R is made up to the lower body L, preferably at the surface, an alignment flat 82 engages a similarly oriented alignment flat 84. Alignment flat 82 is on the housing 72, while alignment flat 84 is on communication crossover 86. The crossover 86 contains a passage 88 which is an extension of passage 48. Passage 88 terminates in a projection 90, which is sealed into the receptacle 78 by O-rings 92 and 94, which are mounted to the projection 90. Although O-rings 92 and 94 are shown, other sealing structures are within the scope of the invention. In essence, the receptacle 78 has a seal bore to accept the seals 92 and 94. The orientation of the opposed flats 82 and 84 ensure that the crossover 86 rotates to orient the projection 90 in alignment with receptacle 78 as the crossover 86 is advanced over the running tool R. To complete the assembly after proper alignment, the running tool R is firmly pushed into the lower body L so that the seal 62 engages seal bore 64, and the locking ratchet assembly 66 fully locks the running tool R to the lower body L. At this time, the crossover 86, which is made up over the running tool R and is now properly aligned, has its projection 90 progress into the receptacle 78. Thereafter, the projection 90 is fully advanced into a sealing relationship into the receptacle 78 so that its passage 48 is in alignment with port 44. This orientation is ensured by alignment of a window 96 in the orientation sub 46 with the groove 54 on the top sub 14 of the running tool R. When such an alignment is obtained, the dog 56 is pushed through window 96 so that it partially extends into the window and partially into groove 54. At that time, the retaining cap 58 is threaded onto thread 60 to secure the position of the dog 56, which, in turn, assures the alignment of port 44 with passage 48. The running tool R is now fully secured to the lower body L of the connection C. Rigid or coiled tubing can now be connected to the running tool R at thread 14.
The bottomhole assembly (not shown), which is supported off the lower end 12 of the body 72, can now be run into position in the wellbore while circulation continues through passage 38 and outlet 28. Ultimately, when the bottomhole assembly is stabbed into a sump packer, circulation ceases and a signal is thus given to surface personnel that the bottomhole assembly has landed in the desired position. At that time, the ball 36 is dropped against the seat 34, and pressure is built up in IC passage 38 above ball 36. This pressure communicates laterally through port 44 into passage 48 and, through the sealed connection of the projection 90 in the receptacle 78, the developed pressure communicates into the control line 74 to the bottomhole assembly. Since, in the preferred embodiment, there are actually a pair of control lines 74, there are multiple outlets 44 in the running tool R such that all the control lines 74 going down to the bottomhole assembly and making a U-turn and coming right back up adjacent the tubular housing 72 and terminating in a similar connection to that shown in
At this point the upper string 98, shown in
The upper body U has some constructional differences from the orientation sub 46 and the crossover 86 used in conjunction with the running tool R. Whereas the components 46 and 86 were assembled by hand at the surface, the counterpart components of the upper body U must connect automatically to the lower body L. Those skilled in the art will be appreciate that the view in
When disconnecting, collet 104 drops into groove 102, and the connection alignment sub 112 and housing 72 start to move apart. To ensure the collet 104 remaining in the groove 102, sleeve 17 (shown in section in
As shown in
Those skilled in the art will appreciate what has been shown is a simple way to test the control line 74 adjacent to the bottomhole assembly without running the upper string 98 with its attendant control line segments. Once the lower portion of the control line 74 has been tested and determined to be leak-free, the running tool R illustrated in
Multiple connectors C can be used in a given string, and the control lines 74 can have outlets at different locations in the well. One of the advantages of using the connector C is that the bottomhole assembly can be run into the well and fully tested along with its associated control lines while the production tubing can be installed at a later time with the remainder of the control line back to the surface. The control line in one application can run from the surface and be connected downhole, as previously described. The control line 74 can continue through a packer through a passage such as 132. Generally speaking, the control line 74 will have a connection immediately above the packer. In multiple packer completions, since it is known what the distance between one packer and the next packer downhole is going to be, a predetermined length of control line can extend out the lower end 134 when the packer shown in
Those skilled in the art will appreciate that the orientation of the male/female components to connect the control line 74 downhole can be in either orientation so that the male component is upwardly oriented or downwardly oriented without departing from the spirit of the invention. The invention encompasses as connector which can be put together downhole and which is built in a manner so as to allow control line testing, as well as functioning of bottomhole components, without having run the upper string and its attendant control line. Thus, it is also within the scope of the invention to connect the control line to the upper string in a multitude of different ways as long as the connection can be accomplished downhole and the connection is built to facilitate the testing of the control line adjacent the bottomhole components, as well as the subsequent operation of the necessary bottomhole components, all prior to inserting the upper string. Those skilled in the art will appreciate that the preferred embodiment described above illustrates a push-together technique with an orientation feature for the control line segment of the joint. However, different techniques can be employed to put the two segments of the connector together downhole without departing from the spirit of the invention.
Any number of different pressure-actuated components can be energized from the control line 74, such as plugs, packers, sliding sleeve valves, safety valves, or the like. The control line, since it runs from the surface down to the bottomhole assembly and back to the surface, can include any number of different instruments or sensors at discrete places, internally or externally along its path or continuously throughout its length, without departing from the spirit of the invention. As an example, the use of fiber optic cable from the surface to the bottomhole assembly and back to the surface is one application of the control line 74 illustrated in the invention. Any number of control lines can be run using the connector C of the present invention. Any number of connectors C can be employed in a string where different control lines terminate at different depths or extend to different depths in the wellbore before turning around and coming back up to the surface.
Certain applications in the context of gravel pack screens in conjunction with fiber optics will now be described.
Referring to
Also visible in
Referring now to
Referring to
In operation, the invention effectively and actively monitors the installation of sand control equipment, its integrity over time and the performance of that equipment. During installation, an exact depth of the sand control equipment is obtainable using a discrete optical signature in the fiber at the location of the downhole equipment and the length of the fiber optic cable that has entered the wellbore. In order to maintain the integrity of the installation and performance thereof, parameters such as chemical species present, vibration, acoustic recognition, pressure, temperature, strain, and density may be queried by the optical demodulator 19 through fiber 17 directly or through integrated sensors. If done directly, monitoring may take place through monitoring point or distributed measurand along the equipment directly through the fiber itself using for example microbending (pressure) Raman Backscatter and optical time domain reflectometry (temperature). Examples of integrated sensor used include interferometry (all parameters) grating, (all parameters) florescence (mostly chemical species, viscosity and temperature) and photoelasticity (temperature, acceleration, vibration and rotational position). From the various measurements, progress and quality of the sand control process can be monitored. The system also provides a real time check on the sand control equipment and will alert surface personnel to problems before damage is done.
It should be noted that the optical fiber 17 can be outside the sand equipment as shown in
Fiber Optic Monitoring of Sand Control Equipment
A method of actively monitoring the installation, integrity, and performance of sand control equipment for the control of unwanted fines that may occur during production, in a well. The instrument is comprised of optical fiber that is integral with, or attached to the inside or outside surfaces of the sand equipment. The optical fiber, or fibers, with or without integrated sensors, will monitor key parameters during the installation process to precisely locate the equipment in the well, monitor all aspects of the installation/completion process, including but not limited to adding aggregate, monitoring of the equipment and then monitoring the integrity and performance of the operational assembly. Typical parameters to be monitored include, but are not limited to chemical species, vibration, acoustic recognition of an event, pressure, temperature, strain, density, and vibration. An embodiment of the instrument is comprised of an optical fiber or fibers attached on the circumference of the sand control equipment in a configuration or pattern determined by the measurement point density desired. The optical fiber attaches to the equipment during the installation into the well. The optical fiber assembly can be comprised of bare optical fiber, or fibers, with or without a variety of coatings and buffers, or optical fiber(s) contained in a cable. The optical fiber assembly can be protected by installing the fiber in channels in the equipment or by the equipment having protuberances to keep the assembly from rubbing the wall of the well. The optical fiber assembly is connected to a fiber optic sensing demodulator either at the surface or at the wellhead. During installation, the exact depth of the sand control equipment can be determined by monitoring the length of the optical fiber from a known point to a location on the downhole equipment that has a discrete optical signature in the fiber. After the equipment is installed, the optical fiber is used to monitor the process of placement of aggregate material in the production interval(s). Through monitoring point or distributed measurand along the equipment, one method being to measure the pressure and temperature along the length of the equipment due to the aggregate being added, the operator can monitor and record the progress and quality of the process. Pressure measurements can be made using discrete sensors along microbending in the fiber or cable. Temperature along a fiber can be measured using combined Raman Backscatter and OTDR techniques. After the installation is complete and the well is in production, the optical fiber, with or without discrete sensors, can be used to monitor the performance and integrity of the sand control equipment and the production parameters of the well as a whole by monitoring point or distributed measurand.
Several embodiments of the fiber optic monitoring of Sand Control Equipment are possible:
A method of actively monitoring the installation process, integrity and operational performance of sand control equipment, for the control of unwanted fines that may occur during production, with a fiber optic system that is placed in proximity to the equipment. The invention is comprised of optical fiber, with integrated distributed or point sensors, placed in proximity to the sand control equipment. The optical fiber is connected to a fiber optic sensing demodulator, to convert the light signals to measurement parameters, at the wellhead or surface. The optical fiber, or fibers, with or without integrated sensors, will monitor key parameters during the installation process to precisely locate the equipment in the well, monitor all aspects of the installation/completion process, including but not limited to adding aggregate, of the equipment and then monitoring the integrity and performance of the operational assembly. Typical parameters to be monitored include but are not limited to chemical species, vibration, acoustic emission, pressure, temperature, strain, density, and vibration.
The primary embodiment of the instrument is comprised of an optical fiber or fibers integrated with a tubing string that is installed into a well and located in the area of the sand control equipment. The optical fiber(s) and tubing string can be continuous, or connected in segments to provide length needed to reach the area of interest in the well. During the installation process, the integrity of the optical fiber can be monitored through, but not limited to, optical time domain reflectometry techniques. Once in place, the optical fiber(s) is connected to a fiber optic sensing demodulator either at the surface or at the well head. During installation, the exact depth of the sand control equipment can be determined by monitoring the length of optical fiber from a known point to a location on the downhole equipment that has a discrete optical signature in aggregate material in the production interval(s). Through monitoring point or distributed measurand along the equipment, one method being to measure the change in temperature along the length of the equipment due to the aggregate being added, the operator can monitor and record the progress and quality of the process. Temperature along a fiber can be measured using combined Raman Backscatter and OTDR techniques, as well as other methods. After the installation is complete and the well is in production, the optical fiber, with or without discrete sensors, can be used to monitor the performance and integrity of the sand control equipment and the production parameters as well as a whole by monitoring point or distributed measurand.
Several embodiments of the fiber optic monitoring of Sand Control Equipment are possible:
The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made without departing from the spirit of the invention.
This nonprovisional U.S. Application claims the benefit of provisional application No. 60/174,412, filed on Jan. 5, 2000.
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Number | Date | Country | |
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Number | Date | Country | |
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60174412 | Jan 2000 | US |