Apparatus and Method For Remote Actuation of A Downhole Assembly
An apparatus and method is disclosed for remotely operating a downhole tool within a wellbore. The wellbore extends from a ground or subsea surface downward into the earth. The apparatus includes a tool having a production assembly with at least one sleeve adapted for movement from a first sleeve position facilitating entry of formation fluids past the sleeve into the wellbore to a second sleeve position that retards entry of formation fluids. The downhole tool may be configured to resume production following fracturing, gravel packing or other operations without the need for additional trips into the well for the purpose of opening production sleeves. A fluid pressure pulse or electromagnetic signal or other signal may be delivered downhole for remote mechanical actuation of the apparatus.
This application claims priority to U.S. Provisional Patent Application No. 61/358,331, filed Jun. 24, 2010.
FIELD OF THE INVENTIONThe invention is directed to apparatus, systems and methods for remotely actuating equipment in a wellbore.
BACKGROUNDIn the production of oil and gas, recently drilled deep wells reach as much as 25,000 or even 30,000 feet or more below the ground or subsea surface. Offshore wells may be drilled in water with a depth of as much as 10,000 feet or more. The total depth from offshore platform to the bottom of the wellbore can be as much as eight miles. Such extraordinary distances in modern well construction cause significant challenges in equipment, drilling and servicing procedures.
Tubular strings are introduced into a well in different ways. A wellbore service string may require many days to make a “trip” into a wellbore, which may be due in part to the time consuming practice of making and breaking pipe joints. The time required to assemble and deploy any service tool assembly downhole for such a long distance is very time consuming and costly. In well service operations, saving time and steps is very important, because the cost per hour to operate a drilling or production rig is very expensive. Each trip into the wellbore adds expense. and increases the possibility that tools may become lost in the wellbore requiring still further operations for their retrieval.
Various companies offer enhanced so-called “single trip” multizone systems that are designed to enable the fracturing and/or gravel packing of multiple oil producing zones. Such systems, including the ESTMZ™ system marketed by Halliburton Energy Services of Dallas, Tex. are directed at minimizing the number of rig days required to complete conventional fracture and gravel packing operations in multiple pay zones. By “single trip”, it is meant that the service of fracturing or gravel packing multiple zones may be performed in some instances using one trip into the wellbore for such operations. The systems allow an operator to fracture and gravel pack wells without making multiple “trips” into the well for each fracturing or gravel packing operation.
However, once the fracturing operations are complete, and the fracturing fluid has been pumped through the service tool into the formation in multiple zones, it is customary to proceed into the wellbore once more (another time or trip) using an isolation string carrying a mechanical shifting tool. Such a shifting tool is employed to open mechanical sliding sleeves that were closed during the fracturing operations, thereby allowing production of formation fluids into the wellbore.
Another commercially available system is known as ComPlete™ MST multizone system marketed by BJ Services Company of Houston, Tex. This system isolates and then fractures individual zones in a multizone well using a mechanical assembly. It is common for such mechanical assembly systems to have a total length of 1,000 feet or more. Then, after the zones are isolated and treated with this lengthy assembly, using one trip, it is common to run another trip into the well employing an upper production string or “inner” string. This additional step typically requires running back into the well to open production sleeves with mechanical shifting tools, thereby allowing formation fluids to flow into the wellbore.
In many deep wells offshore, the amount of time needed to run an additional string down the wellbore following a fracturing event, to close production sleeves and facilitate production may be very significant. For example, it is not unusual for such a trip procedure to require as much as 10-30 hours of time on a drilling rig. On some offshore rigs, the calculated daily cost of “rig time” can be as much as one million dollars per day, or more. Thus, the cost measured in time of a single trip may be very large.
Mechanical shifting tools contact and mechanically shift production sleeves to facilitate production of formation fluids into the wellbore. Unfortunately, in soft rock formations, significant losses of completion fluids of as much as 300 barrels of completion fluids per hour may be experienced once the first screen or sleeve is opened. These losses may occur into the subterranean formation. Drilling rigs are limited in the quantity of completion brine carried on the rig. Large losses of brine to the formation may lead to the necessity to use viscous pills or other means to reduce such losses. Viscous pills may cause formation damage, especially if they are used subsequent to fracturing operations.
A continuing challenge in the industry is to develop and complete multi-zone wells using the least amount of rig time and the least amount of trips into the wellbore. Furthermore, it is a challenge to conduct wellbore operations while reducing losses of completion fluid to the formation. This invention is directed to improvements in apparatus and methods for conducting such operations.
BRIEF SUMMARY OF THE INVENTIONAn apparatus and method is disclosed for remotely operating a downhole tool within a wellbore. The wellbore extends from a ground or subsea surface downward into the earth. The apparatus may comprise a downhole tool having a production assembly with at least one sleeve adapted for movement from a first sleeve position facilitating entry of formation fluids past the sleeve into the wellbore to a second sleeve position that retards entry of formation fluids. The downhole tool may be provided with an internal cavity adapted for passage of wellbore fluids under elevated pressure. The downhole tool may be operated in connection with tubular screens or sand screens provided with annular concentric flowpaths separating the fluid from the internal cavity. Further, there may be a separation between the concentric space within the downhole tool and the production sleeve having an external shroud.
The apparatus may include a sensor configured to measure a value as a function of time. In some embodiments, this value(s) transmitted comprises fluid pressure as a function of time, in which the sensor is a pressure sensor configured to receive pressure pulses and generate electrical signals correlated to the value of such pressure pulses. In other embodiments, the sensor may be an electromagnetic sensor adapted to sense electromagnetic signals, and then generate electrical signals. In either of such embodiments, a control module may be adapted for receiving and analyzing electrical signals received by the control module from the sensor. The control module may include operating instructions representing predetermined parameters, and may be configured to receive from the sensor signals corresponding to transmitted values. A control module is capable of comparing such values to predetermined parameters so that when such values exceed predetermined parameters the control module sends action signals.
A motor is configured to receive action signals sent from the control module. A motor may be adapted for applying direct or indirect force to open or close a sleeve of a production assembly to alter the flow path of formation fluids through the sleeve. For example, following fracturing one or more producing zones, it may be desirable to open the sleeve of a production assembly to facilitate the flow of formation fluids beyond the sleeve into the production assembly.
In one embodiment of the invention, a hydraulic system may be connected to a motor. The hydraulic system may include a pump configured for applying hydraulic forces to control lines. Control lines may be operatively engaged, directly or indirectly, to the sleeve of the production assembly. Upon activation of control lines, it is possible to open or close the sleeve, thereby altering flow path of formation fluids. The sleeve may be opened or closed several times as required by deployment or production operations.
The invention may be observed by reference to one or more Figures as follows.
As indicated, a sensor may be employed to receive signals in the practice of the invention. These signals are not random, but instead are deliberate and designed to be of a format (intensity and time) that would not occur under normal conditions. Thus, a signal generating device may be employed and positioned remotely from the sensor. The signal generating device (such as a pump, electromagnetic generating apparatus or other similar device) may be configured to create signals. Such signals may represent, in some cases, pressure pulses in fluids passing through or along the internal cavity from a point adjacent the ground or subsea surface to a lower position downhole. In other embodiments, the signal generating device may be configured to produce electromagnetic signals. Such signals typically will be created for predetermined intensity and time values. Such values are chosen to avoid intensity and time values that would be seen in normal operation, to avoid an inadvertent trigger of the apparatus.
In the practice of the invention, the signal generating device could be a commercially manufactured pump, as would be used in oilfield service industry for fluid pumping applications. In other embodiments, the signal generating device may be an electromagnetic signal generating device.
A battery may be configured for supplying power to the sensor, the control module and/or the motor. The apparatus may be configured for deployment in connection with a multi-zone wellbore completion system having a number of screen assemblies. A shroud is provided, the shroud being configured as a conduit for flow of formation fluids among or between a number of screen assemblies.
In other embodiments of the invention which employ pressure pulses, such embodiments may employ a second or additional pressure sensor wherein the second pressure sensor is positioned near or opposite the first pressure sensor, and can be used to determine the difference in pressure between the two sensors. The additional pressure sensor may be configured to receive pressure pulses and generate signals to the control module. The additional pressure sensor may be configured to measure changes in pressure due to frictional pressure drop generated by turbulent flow. The control module may be configured to evaluate the difference between pressure signals measured at both pressure sensors when more than one such sensor is employed.
In another aspect of the invention, a first temperature sensor may be positioned below the ground or subsea surface. The first temperature sensor may be configured to measure temperature, and the control module may include instructions representing predetermined temperature parameters. These temperature parameters may be pre-loaded into the control module and selected for a particular well servicing event. The control module may be configured to refrain from sending action signals so long as the temperature measured at the first temperature sensor is below a predetermined minimum temperature parameter. In this manner, the chances of accidental or inadvertent sending of action signals may be minimized by combining temperature and pressure measurements.
The invention also may be described as a method for remotely controlling the production flow path of formation fluids through the sleeve of a production assembly in a fluid-containing wellbore. The method may include the step of generating signals for transmission in a wellbore, such that the signals travel downhole from a point near the ground or subsea surface. The signals may be pressure pulses and may have certain defined and predetermined intensity and time values. The pressure pulses may propagate from a position near the ground or subsea surface through the fluid and into a cavity within the wellbore to a production assembly positioned downhole. In other applications, the signals may be electromagnetic signals.
It is desirable in certain applications of the invention to activate a pressure sensor, the sensor being configured to measure fluid pressure variations as a function of time. The pressure sensor may be adapted to receive pressure pulses and then generate in response electrical signals correlated to the value of received pressure pulses.
A control module may detect electrical signals from the pressure sensor. The control module may be adapted for receiving signals from the pressure sensor. The control module may be pre-loaded with operating instructions having predetermined pressure and temperature parameters chosen by an operator for a particular well or well configuration. The control module may be configured to receive from the pressure sensor electrical signals corresponding to pressure pulse values.
The control module may be configured to compare received pressure pulse values to predetermined parameters to determine if the measured pressure pulse values exceed predetermined parameters. If the values exceed or meet predetermined parameters, action signals may be sent to a motor. Then, it may be useful to manipulate the sleeve of a production assembly to alter the flow of formation fluids beyond the sleeve and into the wellbore, allowing production of formation fluids to commence.
The motor may be connected to the sleeve of the production assembly. In some applications, a hydraulic system may be connected to the motor. The hydraulic system may be configured with a pump to receive forces from the motor. The hydraulic system may include as well hydraulic control lines that are capable of applying force to the sleeve of a production assembly. In many cases, a sleeve will be opened using the hydraulic system to facilitate flow of formation fluids beyond the sleeve and into the production assembly. The method may be performed following the fracturing (i.e. stimulation) of one or more zones of the formation. The method in some cases may be performed following gravel packing operations or other operations, including for example squeeze and circulating procedures and real time annulus monitoring operations.
In one embodiment of the invention, a control module may be used to control a hydraulic tool. The hydraulic system may include control lines for providing forces to the sleeve. A pump may drive hydraulic fluid along a circuit, the pump being controlled by electronic signals from a control module. The control module may be programmed to respond to a specific trigger, such as a pressure pulse, or a signal representing a temperature measurement, or an electromagnetic signal, or any of these types of signals. This may be accomplished with or without control lines, depending upon the configuration.
In one specific embodiment, the system may respond to a pre-defined pressure pulse generated at the surface for a pre-defined period of time. In such a case, it is advantageous to choose a pressure pulse that would be highly unlikely to be produced during normal operations to avoid inadvertent triggering of the motor by the control module. Pressures applied outside of the predetermined values and time intervals may be ignored, allowing unlimited pressure points to be applied downhole without activating the apparatus. The control module may be configured to distinguish its own commands from naturally occurring applied pressures or pressure pulses generated by the gravel pack or fracturing operations. Once a trigger has been detected and executed, the apparatus is capable of reset to wait for another trigger to initiate the next task.
It is anticipated that the control module could be applied to essentially any hydraulically operated tool. The system facilitates remote and wireless communication with a downhole production assembly. In some applications, the energy storage capacity, or battery life, may limit the amount of time that the apparatus is capable of responding, but in the practice of the invention a battery configuration may be chosen that will develop sufficient power for a sufficient length of time to achieve the advantages of the invention. The invention may be coupled with downhole power generation sources to recharge the battery or directly power the control module, sensors and motor/pump assembly. Downhole power may be generated from the surface and transmitted by various means available (i.e. fluid, tubing, control line). Energy available downhole can be used to drive an in situ power generation system in some embodiments of the invention.
Referring now to the Figures,
In
A second embodiment of the invention is illustrated schematically in
The second embodiment of the invention is illustrated by
Pressure sensor 102 (
Further, as shown in
For purposes of this invention, it is believed that a battery of about 7 to about 22 volts can be used as a source of power, for either the first or second described embodiments. The pump may be chosen to deliver in the range about 5,000 psi of pumping force, but less or more force could be deployed, for example about 3000 to about 10,000 psi, depending upon the configuration.
An additional pressure sensor could be positioned on mandrel 110 on the opposite end to the first sensor 100. A second sensor could measure pressure and/or temperature inside annular space 112. A third sensor could be positioned on the same end of mandrel 110 as the first sensor 102, but measuring pressure and temperature inside annular space 112. The difference in pressure between the second and third pressure sensors could provide an indication of the rate of production whether or not the frictional loss in annular space 112 is such that sleeve 106 should be opened. It is assumed that apparatus 75 would have remained closed by choice. Further sensor arrangements could be designed as to detect water production and shut off flow from annulus 112 into cavity 92 (
In another embodiment of the invention (not specifically illustrated in the Figures), the control module could be physically separated a considerable distance from the production sleeves. The control module could be provided having one or several pressure and temperature sensors, an electric motor, and a hydraulic pump connected to one or more hydraulic control lines. The control module could be located above the modular screens (uphole) and quite some distance away from the screens. In such an embodiment, the control module could be connected to the multiple production sleeves by hydraulic control lines running along the screens inside cavities provided for this purpose, for a considerable distance along the apparatus. The control lines would be capable of transmitting hydraulic power to multiple production sleeves adjacent to multiple producing zones of a formation to shift them open or closed, as required. Thus, the invention could find application in production assemblies designed for many producing zones in a formation.
This disclosure and description of the invention are illustrative, and various changes in the method of deployment of the apparatus of the invention may be employed without departing from the spirit and scope of the invention. By way of example, the signal generating device described herein could be an electromagnetic signal generator that is used with corresponding receivers (such as electromagnetic sensors) to achieve the purpose or advantages of the invention. In one such embodiment, a wireless data communications system could be employed either as one way or bi-directional, and this could be accomplished using a wireless transmission method, including for example acoustic waves, acoustic stress waves, electrical, electromechanical force, electromagnetic force (“EMF”), optical or other means.
Claims
1. An apparatus for remotely operating a downhole tool within a wellbore, the wellbore extending from a ground or subsea surface downward into the earth, the downhole tool comprising a production assembly having at least one sleeve adapted for movement from a first closed position blocking entry of formation fluids past the sleeve and into the wellbore to a second open position that allows entry of formation fluids, the downhole tool having an internal cavity, the internal cavity being adapted for passage of wellbore fluids, the apparatus comprising:
- (a) a sensor, the sensor being configured to receive transmitted signals and then generate electrical signals responsive to the value of such transmitted signals;
- (b) a control module, the control module being adapted for receiving electrical signals from the sensor, the control module further comprising operating instructions representing predetermined parameters, the control module being configured to receive from the sensor signals corresponding to values and to compare such values to predetermined parameters such that when received values exceed predetermined parameters the control module is capable of sending action signals in response; and
- (c) a motor configured to receive such action signals from the control module, the motor being adapted for applying force to open or close a sleeve of a production assembly to alter the flow path of formation fluids through the sleeve.
2. The apparatus of claim 1 additionally comprising the following:
- (d) a hydraulic system connected to the motor, the hydraulic system further comprising a pump, the pump being configured for applying hydraulic force to control lines, the control lines being operatively engaged to a sleeve of the production assembly to open or close the sleeve, thereby altering the flow path of formation fluids.
3. The apparatus of claim 1 further wherein the sensor is a pressure sensor, further wherein the pressure sensor is adapted for receiving pressure pulse signals, further comprising a signal generating device positioned remotely from the pressure sensor, the signal generating device being configured to create pressure pulses in a fluid passing through the internal cavity, the pressure pulses having predetermined intensity and time values.
4. The apparatus of claim 1 further comprising a battery configured for supplying power to at least one of the following: sensor, control module, motor.
5. The apparatus of claim 1 configured for deployment in connection with a multi-zone wellbore completion system having a plurality of production assemblies.
6. The apparatus of claim 1 further comprising a shroud and mandrel, the shroud being configured as a conduit for flow of formation fluids among a plurality of production assemblies, further wherein the shroud is configured to be lockable in rotation with the mandrel.
7. The apparatus of claim 3 further comprising an additional pressure sensor, wherein the additional pressure sensor is positioned downhole, the additional pressure sensor being configured for measuring changes in pressure due to pressure drop generated by turbulent flow.
8. The apparatus of claim 1 wherein the apparatus further comprises a first temperature sensor positioned below the ground or subsea surface, the first temperature sensor being configured to measure temperature, further wherein the control module comprises instructions representing predetermined temperature parameters.
9. The apparatus of claim 8 wherein the control module comprises instructions to refrain from sending action signals when the temperature measured by said first temperature sensor is below a predetermined minimum temperature parameter.
10. The apparatus of claim 1 wherein the sensor comprises an electromagnetic sensor.
11. A method for remotely controlling the production flow path of formation fluids through the sleeve of a production assembly in a fluid-containing wellbore, the wellbore extending from a ground or subsea surface downhole into a subterranean formation, the subterranean formation having at least one producing zone, the method of the invention comprising the steps of:
- (a) activating a sensor, the sensor being adapted to receive transmitted signals and generate in response electrical signals correlated to the value of received transmitted signals;
- (b) detecting with a control module electrical signals from the sensor, the control module being adapted for receiving signals from the sensor, the control module further comprising operating instructions having predetermined parameters, the control module being configured to receive from the sensor electrical signals;
- (c) comparing received signal values to predetermined parameters to determine if measured signal values exceed predetermined parameters, thereby triggering the production of action signals;
- (d) sending action signals to a motor, the motor being configured to receive action signals and apply forces which operate on the sleeve in response, and
- (e) manipulating the sleeve of the production assembly to alter the flow of formation fluids.
12. The method of claim 11 wherein a pumping apparatus generates such transmitted signals in the form of pressure pulses in the fluid within the wellbore, such pressure pulses having certain defined and predetermined intensity and time values, the pulses propagating from a position near the ground or subsea surface through the fluid and into a cavity within the wellbore to a production assembly positioned downhole.
13. The method of claim 11, wherein the motor is operably connected to the sleeve of the production assembly, wherein the manipulating step further comprises activating a hydraulic system connected to the motor, such hydraulic system being configured with a pump that receives forces from the motor, the hydraulic system having hydraulic control lines capable of applying force to the sleeve of the production assembly.
14. The method of claim 11 wherein the manipulating step comprises opening the sleeve to facilitate the flow of formation fluids beyond the sleeve and into the production assembly.
15. The method of claim 12 wherein, prior to the step of generating pressure pulses, a fracturing fluid is passed through the wellbore and into the subterranean formation, thereby fracturing a first zone of the subterranean formation to form a first fractured zone.
16. The method of claim 15 further including the step of gravel packing the first fractured zone following the fracturing step.
17. The method of claim 11 wherein the sensor comprises an electromagnetic sensor.
Type: Application
Filed: Jun 23, 2011
Publication Date: Mar 15, 2012
Inventor: Christian Capderou (Cypress, TX)
Application Number: 13/167,376
International Classification: E21B 34/06 (20060101); E21B 34/00 (20060101);