NO20120677A1 - Apparatus and technique for communicating with a rudder-promoted perforation gun - Google Patents

Abstract

One technique that can be used with a well includes the use of a string that includes a pipe-transported perforation gun (TCP). The technique includes using a wellbore component of the string to communicate up from the wellbore an indication of at least one depth or orientation of the cannon.

Description

APPARATUS AND TECHNIQUE FOR COMMUNICATING WITH A TUBE-PORTED PERFORATING GUN

CROSS REFERENCE

This application is an international application of US Non-Provisional Application Serial No. 12/632,083 (Attorney Docket No. 22.1652), entitled “Apparatus and Technique for Communicating with a Pipe-Transported Perforator Gun” filed on Dec. 7, 2009 and incorporated hereby reference

BACKGROUND

[001] The invention generally relates to an apparatus and a technique for communicating with a pipe-transported perforating gun.

[002] For the purpose of producing well fluid from a formation, the formation is usually perforated from within a wellbore to improve fluid communication between the reservoir and the wellbore. To perform the perforation, a perforating gun is typically lowered downhole (eg, on a string) within the borehole of the area of the formation to be perforated. The perforating gun typically contains perforating charges (eg, matched charges) that are arranged in a phased pattern around the longitudinal axis of the cano and are radially oriented toward the wellbore wall. The perforating charges are fired to pierce the casing string of the wellbore (if the well is cased) and produce radially extended perforating tunnels into the formation.

[003] Modern perforation technology has evolved from simply making simple holes in the casing string to being custom-made, objective-oriented services that are integrated into sophisticated and versatile completion designs. Perforation is now used to optimize both permanent completions and temporary completions, such as completions of drill string tests and completions of well overhauls. Together with services such as hydraulic fracturing, sand management, awik drilling of high deviation and horizontal wells, completion fluid technique and well testing, completed perforation to achieve communication between the formation and the borehole has become an important factor in improving the productivity of the well.

[004] There are many factors in a successful perforating operation, such as the ability to accurately control the depth of the perforating gun or the angular orientation of the perforating gun about the longitudinal axis of the gun. Another factor associated with the success of a perforation operation is the time needed to perform the operation.

[005] The manner in which a perforating operation is carried out also depends on the type of perforating gun. For example, the setting of a conventional pipe-transported perforating gun (TCP) is usually controlled solely on logs and other data obtained prior to the perforating operation. Furthermore, parts of the operations' success and performance are usually assessed after the job, i.e., after the gun string is pulled out of the hole and other services are performed (eg, a production logging tool to measure flow rates in the wellbore.)

SUMMARY

[006] As an example, one technique that can be used with a well includes obtaining a string that includes a pipe-transported perforating gun (TCP). The technique includes using a wellbore component of the string to communicate up the wellbore an indication of at least one depth or orientation of the gun.

[007] As another example, a system that can be used with a well includes a string to be placed in the well. A TCP cannon and a transmitter are placed in the string. The transmitter communicates up from the wellbore an indication of at least one depth or orientation of the TCP gun.

[008] Advantages and other functions of the invention will be clear from the following drawings, descriptions and patent claims.

BRIEF DESCRIPTION OF THE DRAWING

[009] Figures 1 and 3 are schematic diagrams of the pipe transport perforating gun (TCP) systems according to various examples.

[0010] Fig. 2 is a flow diagram showing a technique for positioning and firing a TCP cannon according to various examples.

[0011] Fig. 4 is a flow diagram showing a technique for placing and firing multiple TCP guns according to an example.

DETAILED DESCRIPTION

[0012] In the following description, a number of details are presented to provide an understanding of the present invention. However, it will be understood by those skilled in the art that the present invention can be used without these details and that a number of variations or modifications of the described embodiments are possible.

[0013] As used herein, the terms "above" and "below", "up" and "down", "upper" and "lower", "up" and "down", and other similar terms indicating relative positions above or below a given point or element, used in this specification to describe more clearly some embodiments of the invention. However, in the case of equipment and methods for use in wells that are deflected or horizontal, such designations may refer to a left-to-right, right-to-left, or diagonal relationship as appropriate.

[0014] Fig. 1 shows an example of a pipe-transported perforation system (TCP) 5 according to an example. Typically, the TCP system 5 includes a tubing string 14 extending down a wellbore 11. The tubing string 14 may be one of many different types of tubing strings, such as a production tubing string, a test string, a drill stem test string (DST), etc. Regardless of its particular use, the pipe string 14 includes at least one TCP perforating gun, such as a TCP gun 30 which is described in FIG. 1.

[0015] In the context of this application, a "TCP gun" means a perforating gun designed to be fired in response to a pressure-based stimulation or pressure-based stimulations that are communicated downhole through a central passage in a tubing string from the surface of the well to a position close (eg, within 10 feet) or at the TCP cannon. The pressure stimulation or stimulations may be in the form of command coded pressure pulses, absolute pressure, differential pressure, etc. As a non-limiting example, the perforating charges of the TCP gun 30 may be fired by being fired by increasing the internal pressure of the tubing string 14 above a threshold, so that the TCP gun 30 responds to the increased pressure level by firing its perforating charges.

[0016] It is noted that, as described below, string 14 includes a wellbore telemetry system 20 for the purpose of establishing uphole communications, and the uphole communications may involve, e.g., the use of pressure-based stimuli communicated up from the borehole through the string, as well as the use of other types of stimuli (acoustic stimuli, electromagnetic stimuli, etc.) which may or may not be communicated through the string 14.

[0017] Even on fig. 1 shows the pipe string 14 as extended down into the borehole inside a borehole 11 which is lined with a casing string 13, it is noted that fig. 1 is only one example among many possible implementations of a TCP system. In this way, the borehole where the TCP gun 30 is extended can be lined or unlined, depending on the particular design. Furthermore, the TCP gun 30 may be extended in a lateral deviation or high deviation borehole, according to other embodiments. In addition, the TCP perforation system 5 can be used in a subterranean well or a subsea well, depending on the particular design.

[0018] Before the perforating charges of the TCP gun 30 are fired, the TCP gun is first driven downhole as part of the string and using real-time position feedback provided by the downhole telemetry system 20 (as described below), the TCP canoe is set correctly. Thereby, unlike conventional TCP systems, the TCP gun 30 is not placed blindly, but on the contrary, real-time feedback is provided about the well position, which allows an operator at the surface of the well to monitor the feedback and make the necessary adjustments to accurately place the gun 30. Typically, the TCP gun "position" refers to the angular orientation of the TCP gun 30 (ie, the azimuth or angle of the TCP gun 30 impinging on the longitudinal axis 19 of the gun and referred to herein as the gun "orientation") and the depth of the gun 30.

[0019] The wellbore telemetry system 20 is placed in the borehole close to (within, e.g., ten feet of) the TCP gun 30 and is designed to communicate with a telemetry system 12 that is placed on the surface of the well. The communication between telemetry systems 12 and 20 may be through the pipe string 14 (acoustic or liquid pulse type communication), for example, through wired communication lines, through electromagnetic (EM) communication telemetry through signals 16 and 17 as shown in FIG. 1 or through some other type of wireless or wired telemetry communication plan or medium, depending on the particular implementation.

[0020] Typically, a transmitter 27 in the downhole telemetry system 20 is constructed to generate stimuli (pressure stimuli, acoustic stimuli, electrical stimuli, electromagnetic (EM) stimuli, etc.) that are received by the surface telemetry system 12 for the purpose of communicating an indication of the position ( orientation and/or depth) to the TCP gun to the surface of the well in real time. For example, the transmitter 27 may communicate indications of the orientation and depth of the TCP gun 30 to the surface telemetry system 12. Therefore, an operator at the surface of the well, based on the received position of the TCP gun 30, may take appropriate action to ensure that The TCP gun 30 is in the correct position before taking action to fire perforating charges from the gun 30.

[0021] The downhole telemetry system 20 may also include a receiver 28. Typically, the receiver 28 may communicate with the surface telemetry system 12 for the purpose of receiving command coded stimuli that direct the location of the TCP 30, according to some embodiments. In other embodiments, commands are not communicated downhole for the purpose of changing the position of the TCP gun 30, but instead the string 14 is physically manipulated to change the position of the gun, as further described below. It is noted that receiver 28 may also serve the dual function of receiving a pressure stimulus encoding a command to fire the gun's perforating charge, although a separate receiver (not shown in Fig. 1) may be part of the TCP gun for this purpose. purpose, in other embodiments.

[0022] In addition to the downhole telemetry system 20, the tubing string 14 may include other equipment associated with providing feedback on the position of the TCP gun and positioning the gun 30. For example, the tubing string 14 may include an energy source stored in the wellbore, such as a battery 22, for the purpose of supplying power to the electrical components in the string 14, such as the borehole telemetry system 20. The battery 22 can supply power to other components in the pipe string 14, such as a depth measurement equipment 24, an orientation sensor equipment 33, a gun orientation equipment 31 (if an active power-consuming device) and other power-consuming components of the TCP cannon 30, as non-limiting examples.

[0023] The depth measurement equipment 24 can take a variety of forms, such as a casing collar locator (CCL), a gamma ray equipment, etc., depending on the particular embodiment. In this regard, the signal provided by the CCL or the gamma ray equipment in real time to the surface of the well (via the borehole telemetry system 20) can be correlated at the surface with a previous well log to determine the depth of the TCP gun 30. Therefore, regardless of its particular form, the depth measurement equipment 24 is designed to provide an indication of the depth of the perforating gun 30 and interact with the transmitter 27 for the purpose of communicating an indication of the depth of the TCP gun 30 to the surface of the well in real time.

[0024] The orientation sensor device 33 senses the angular orientation of the TCP gun 30. As a non-limiting example, the orientation sensor device 33 may be a gyroscope in one embodiment. The signal given by the orientation sensor equipment 33 is given to the transmitter 27, which sends the signal to the surface of the well in real time.

[0025] In some embodiments, the gun orienting equipment 31 is an active orienting equipment that orients the TCP gun based on a command that is communicated in the wellbore and is received by the receiver 28. More specifically, in some embodiments, the gun orienting equipment responds to command coded stimuli that are sent from the surface to incrementally or completely orient the TCP guns 30. As a non-limiting example, the orientation equipment 31 may include an electric motor (as a non-limiting example), which receives electrical power from the battery 22 and a command interface (not shown) to receive signals that is received by the borehole telemetry system 20. The command interface decodes all commands for the equipment 31 and generates the appropriate control signals for the motor to rotate the TCP gun 30 at the desired position.

[0026] As a non-limiting example, in one embodiment, the surface telemetry system 12 and the borehole telemetry system 20 may communicate wirelessly using extremely low frequency electromagnetic (EM) signals. For this purpose, the two-way signals 16 and 17, which are communicated between the electrical systems 12 and 20, may use electromagnetic carrier waves having frequencies in the range of 0.1 to 1.0 hertz (Hz). As a more specific example, the frequency range may be in the range of 0.25 to 8 Hz as a non-limiting example. As another non-limiting example, the distance between the telemetry systems 12 and 20 may be between about 3000 meters (m), in some embodiments, although greater or lesser distances may exist in other applications.

[0027] In some embodiments, the EM communication between the telemetry systems 12 and 20 is achieved by the injection of a modulated voltage into the formation via an electric dipole. The voltage difference induced by the current in a closed circuit is measured along the walls of the casing string 12 with a relay or between the wellhead and a distant post on the surface. The voltage is demodulated to extract the information from the signal. The communication itself may be based on phase modulation of the injected voltage, although other types of modulation (eg, frequency modulation) may be used in other embodiments. As a non-limiting example, the bit rate may be about one bit per second, and data frames in the messages may be about a minute long, although other data rates and frame rates are contemplated in other embodiments.

[0028] With reference to fig. 2 together with fig. 1, according to some embodiments, a technique 100 may be used for the purpose of placing and firing the TCP gun 30.1 according to the technique 100, a rod containing a TCP gun is driven into a well, according to block 104. A procedure then begins to position the TCP guns correctly at the appropriate orientation and depth. In this position, an indication of at least one depth or orientation of the gun is communicated in real time from a location in the borehole near the gun to a location near the surface of the well, according to block 108.

[0029] Based on the indication(s), a decision is then made (diamond 112) whether the TCP gun is ready to fire. If not, then at least one iteration is performed adjusting the position of the TCP cannon. For example, an indication of at least one command to regulate the orientation of the TCP cannon may be wirelessly communicated from the surface to a position near the cannon, according to block 114. These actions may also or alternatively include selectively physically manipulating the string containing The TCP gun to adjust the depth of the gun, according to block 116. The iterations continue by returning to block 108 where an indication of at least the depth or azimuth of the gun is communicated up the borehole, according to block 108. The TCP gun is finally fired (block 120) when the iteration ends at the decision that the TCP cannon is ready to fire, according to rhombus 112.

[0030] Other embodiments are being considered and are within the scope of the attached patent claims. For example, in another embodiment, the TCP gun may be oriented using a passive orientation system, such as pivots and weights, instead of the active orientation system described above. For this passive orientation system, the string 14 may be lifted, driven downhole and/or rotated to adjust the orientation of the TCP gun 30 based on the indication of the gun's orientation provided in real time by the downhole telemetry system 20. In this way, by adjusts the depth of the string 14, the rotations of the TCP gun 30 are also adjusted due to the changed inclination of the borehole 11.

[0031] As another example of a variation, although FIG. 1 shows a TCP system 5 for a single TCP cannon, the systems and techniques disclosed herein may similarly be applied to a pipe string 202 containing multiple TCP cannons 30, as shown in FIG. 3.1 in this respect, with reference to fig. 3, the tubing string 202 of a multiple TCP gun perforating system 200 includes two or more perforating units 220 (perforating units 220i through 220N, which are shown as examples in FIG. 3), which are spaced apart at desired intervals in the well. In this example, each perforation hole 200 includes a TCP gun 30, a depth gauge device 24, an orientation sensor device 33, and an orientation device 31.

[0032] In each unit 220, the depth measurement equipment 24 senses the depth of the relevant TCP gun 30 and communicates this depth to the transmitter 27, which then wirelessly communicates an indication of this depth to the surface in real time.

[0033] Likewise, the orientation sensor equipment 33 for each unit 220 communicates an indication of the measured orientation of the associated TCP cannon 30 and communicates this measured orientation to the transmitter 27, which then communicates an indication of the orientation to the surface in real time. In addition, the orientation equipment 31 of each unit 220 passively or actively orients its associated TCP cannon 30, as described above.

[0034] It is noted that fig. 3 only shows an example of a string with multiple TCP canons. Other variants are being considered and are within the scope of the attached patent claims. For example, in other arrangements, each perforating gun unit 220 may include a telemetry system similar in design to the telemetry system 20 . As another example, orientation or depth sensing equipment may be shared by one or more TCP guns 30. As another example, a single motor or a single weight and rotation system may be used to orient multiple TCP guns 30.

[0035] Several TCP guns in a particular pipe string can be positioned and fired according to a technique 300 which is shown in FIG. 4. With reference to fig. 4, the technique 300 includes driving a string containing multiple TCP guns into a well, according to block 304. For each of the TCP guns, an indication of at least the depth or orientation of the gun is communicated to the surface of the well in real time, in follow block 308. Based on these indications, a decision is then made, according to block 312, whether the TCP guns are ready to fire. If so, then the TCP guns are fired, in accordance with block 320. Otherwise, for each gun that is not properly aligned, an indication of at least one command may be wirelessly communicated in the borehole to regulate the orientation of the gun, in accordance with block 314. Further, the string may be physically manipulated to adjust the depth of the guns, according to block 316. Alternatively, the string may be physically manipulated to control a passive orientation system. When a decision is finally made that the guns are correctly positioned, according to diamond 312, the perforation guns are fired, according to block 320.

[0036] It is noted that fig. 4 is only an example since other variants are being considered and are within the scope of the appended patent claims. For example, as another variation, not all of the cannons may be finally positioned before they are fired. In this respect, in this embodiment, one or more TCP cannons may be positioned and then fired, another set of one or more TCP cannons may then be positioned and fired, etc.

[0037] While the present invention has been described with respect to a limited number of embodiments, those skilled in the art having the benefit of this disclosure will appreciate that there are countless modifications and variations thereof. It is intended that the appended claims cover all such modifications and variations as fall within the true spirit and scope of the present invention.

Claims (20)

1. A method usable in a well comprising: obtaining a string comprising a pipe-transported perforating gun in the well, and using a component of the string in the wellbore to communicate up from the wellbore an indication of at least a depth or an orientation of the cannon. 2. The method of patent claim 1, where the use includes communicating the indication in real time. 3. The method of patent claim 1, where the use includes wirelessly communicating the indication. 4. The method of patent claim 1, where the use comprises communicating an electromagnetic signal which has a frequency in the value range 0.1 to 1.0 hertz. 5. The method of patent claim 1, which further comprises: Measuring at least the depth of the perforating gun or the orientation of the perforating gun. 6. The method of claim 1, further comprising: communicating to the borehole from the surface of the well an indication of a command to control the orientation of the perforating gun. 7. The method of claim 1, further comprising: physically manipulating the string to adjust the depth of the perforating gun in response to the communication. 8. The method of claim 1, further comprising: physically manipulating the string to adjust the orientation of the cannon in response to the communication. 9. The method of patent claim 1, which further comprises: Firing the perforation cannon after the communication. 10. A system that can be used with a well, comprising: a string to be placed in the well, a pipe-borne perforating gun to be placed in the string, and a transmitter to be placed in the string to communicate up the borehole an indication at least one depth or one orientation of the cannon. 11. The system of claim 10, wherein the transmitter is part of a wireless telemetry system to communicate the indication wirelessly. 12. The system of claim 10, where the transmitter is adapted to communicate the indication in real time. 13. The system of claim 10, further comprising: An orientation device that can be placed in the string near the perforating gun to orient the canoe in response to a remote communication from the surface of the well. 14. The system of claim 10, which further comprises: A battery to power the transmitter. 15. The system of claim 10, wherein the transmitter is adapted to communicate the indication using an electromagnetic carrier wave having an associated carrier frequency in the range of 0.1 to 1.0 hertz. 16. The system of claim 10, which further comprises: A depth measuring device which is placed on the string to measure the depth of the perforating gun. 17. The system of claim 10, which further comprises: An orientation sensor device that is placed in the string to measure the orientation of the perforating gun. 18. The system of claim 17, wherein the orienting equipment comprises a motor to selectively rotate the perforating gun in response to a command received at a position near the perforating gun near the surface. 19. The system of claim 10, further comprising: A receiver positioned in the string to receive an indication of an indication of a command to control an orientation of the perforating gun, the indication being communicated from a position near the surface of the well to a position near the perforating gun. 20. The system of claim 10, further comprising: at least one additional pipe-borne perforating gun to be placed in the string, wherein the transmitter is part of a transmission system to be placed in the string to communicate from a first position near the surface of the well an indication of at least one depth or one orientation of each of said at least one further cannon.