An acoustic-electric coupling downhole intrusion monitoring device and its usage method

Abstract

The invention relates to the technical field of oil and gas drilling, and in particular to an acoustic-electric coupled downhole intrusion monitoring device for drilling and a method for using the same. The monitoring device comprises a centralizer and a monitoring unit, wherein the centralizer comprises a main body and ribs, wherein the ribs are arranged on the outer wall of the main body in parallel along the circumferential direction, and flow grooves are formed between adjacent ribs; the monitoring unit comprises a dielectric component, an acoustic wave component and a signal processing device, wherein the dielectric component comprises a positive electrode and a negative electrode, and the acoustic wave component comprises an acoustic wave transmitting device and an acoustic wave receiving device, wherein the positive electrode and the negative electrode are respectively fixed on the side walls of the ribs on both sides of the flow groove, and the acoustic wave transmitting device and the acoustic wave receiving device are respectively fixed on the side walls of the ribs on both sides of the flow groove, and the signal processing device is electrically connected to the positive electrode, the negative electrode, the acoustic wave transmitting device and the acoustic wave receiving device, and the signal processing device is used to receive signals of the positive electrode, the negative electrode, the acoustic wave transmitting device and the acoustic wave receiving device and process them to obtain monitoring information.

Description

Technical Field

[0001] The invention relates to the technical field of oil and gas drilling, and in particular to an acoustic-electric coupled downhole drilling intrusion monitoring device and a use method thereof. Background Art

[0002] The exploration and development of deepwater and deep-layer oil and gas resources is characterized by high safety risks, high operating costs, and high technical difficulties. Due to insufficient knowledge of deepwater and deep-layer formation information, various downhole accidents are often caused by gas invasion, dissolved gas invasion, and rock debris invasion during the exploration and development process. Therefore, early monitoring and control of invasion is one of the keys to avoiding major accidents such as blowouts.

[0003] Most of the existing intrusion monitoring devices are based on the ultrasonic principle for monitoring. For example, Chinese patent document CN 111364979A discloses a downhole gas intrusion monitoring system based on ultrasonic wave. This method separates the gas-liquid-solid three-phase flow through a turbine combination, and then receives the acoustic wave signal through a self-generated and self-received dual crystal probe and a single-transmitted / single-received single crystal oblique probe to realize the monitoring of early gas intrusion. However, this method has several shortcomings: first, the device is complex and requires the installation of a turbine and a turbine protection device, which cannot meet the complex working conditions downhole; second, the acoustic wave signal must first pass through the wellbore after being emitted, which will greatly attenuate the intensity of the acoustic wave signal; third, only a small part of the acoustic wave signal passing through the wellbore hits the bubble near the well wall and is reflected back and received by the dual crystal probe, and most of the acoustic wave signal is dissipated by refraction, scattering, etc., and the single crystal oblique probe cannot ensure that the installation angle conforms to the migration trajectory of the bottom hole bubble; for example, Chinese patent document CN 115596430 discloses a downhole gas intrusion monitoring system based on ultrasonic wave. A discloses a downhole multi-stage gas intrusion monitoring device and an oil and gas drilling gas intrusion identification method. The main body of the disclosed device is an arc-shaped plate, and a sound wave generator and a sound wave receiver are symmetrically arranged on the outer side of the arc-shaped plate. During use, the device needs to be cast and fixed in a cement ring in order to avoid the influence of the formation environment. This method also has several shortcomings. First, although the device can realize effective monitoring of gas intrusion, it cannot be reused because the device is cast in cement; second, the principle of the ultrasonic gas intrusion detection method is based on the scattering, absorption, and attenuation of ultrasonic signals at bubbles, and finally judging whether gas intrusion occurs at the bottom of the well by the change of the received ultrasonic signal. However, small solid particles such as rock cuttings are also generated during the production process of the oil well, which will also interact with the ultrasonic signal. Therefore, it is impossible to accurately judge whether it is rock cuttings or bubbles that affect the ultrasonic signal, thereby affecting the accuracy of the ultrasonic detection method.

[0004] Moreover, due to the limitation of the principle, the current ultrasonic monitoring of gas intrusion method only has good response characteristics for multiphase flow with obvious acoustic impedance interface (such as bubbles with physical form), but its response characteristics for gas intrusion in a dissolved state are not obvious.

[0005] Therefore, there is an urgent need for an intrusion monitoring device that can cope with complex underground conditions and can be reused to avoid major accidents during the drilling process. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and to provide an acoustic-electrically coupled downhole drilling intrusion monitoring device and a method of using the same. By fixing the monitoring unit on the side of the rib of the stabilizer, the influence of complex downhole conditions on the monitoring unit and the monitoring effect can be effectively overcome, and the device can be used repeatedly. At the same time, the cooperation of the acoustic wave component and the dielectric component can be used to achieve accurate and efficient judgment of various intrusion types.

[0007] In order to achieve the above technical effects, the present invention adopts the following technical solutions:

[0008] An acoustic-electric coupled downhole intrusion monitoring device for drilling, comprising a centralizer and a monitoring unit, wherein the centralizer comprises a main body and fins, wherein the main body is cylindrical, the fins are arranged on the outer wall of the main body in parallel along the circumferential direction, and flow grooves are formed between adjacent fins;

[0009] The monitoring unit includes a dielectric component, an acoustic wave component and a signal processing device, the dielectric component includes a positive electrode and a negative electrode, the acoustic wave component includes an acoustic wave transmitting device and an acoustic wave receiving device, the positive electrode and the negative electrode are respectively fixed on the rib side walls on both sides of the flow slot, the acoustic wave transmitting device and the acoustic wave receiving device are respectively fixed on the rib side walls on both sides of the flow slot, the signal processing device is electrically connected to the positive electrode, the negative electrode, the acoustic wave transmitting device and the acoustic wave receiving device, respectively, and the signal processing device is used to receive the signals of the positive electrode, the negative electrode, the acoustic wave transmitting device and the acoustic wave receiving device and process them to obtain monitoring information.

[0010] The monitoring device provided by the present invention replaces the traditional single-function centralizer with a centralizer with a monitoring unit, without occupying the limited underground space, and effectively overcomes the influence of complex underground conditions on the monitoring unit and the monitoring effect. The centralizer is lowered into the well and raised into the well together with the drill pipe. After the monitoring is completed during the drilling process, it can be removed and installed at the next drilling site that needs to be monitored. The monitoring device can be reused many times.

[0011] At the same time, in the monitoring device provided by the present invention, the monitoring devices in the monitoring unit, namely the positive and negative poles of the dielectric component and the transmitting and receiving devices of the acoustic wave device, are respectively fixed on the rib side walls on both sides of the same current slot. Compared with the existing monitoring device, the spacing between the monitoring devices is effectively reduced, ensuring that the measured data is more accurate.

[0012] Preferably, the side walls of the fins are provided with dielectric component fixing grooves and acoustic wave component fixing grooves.

[0013] Further preferably, the rib sidewall is also fixed with an acoustic wave component protection cover, and the acoustic wave component protection cover completely covers the acoustic wave component fixing groove. The acoustic waves generated by the acoustic wave component can pass through the acoustic wave component protection cover by the principle of transmission. Therefore, in order to prevent the rock debris, mud and sand and other solid particles carried in the multiphase flow from causing damage to the acoustic wave component, the acoustic wave component protection cover can be set to effectively protect the acoustic wave component.

[0014] Further preferably, a rounded corner is provided at the junction of the dielectric component fixing groove and the rib side wall. An electric field is generated between the positive and negative electrodes of the dielectric component for monitoring, and there must be no obstacles or protective covers between the two to ensure its monitoring accuracy. Therefore, the dielectric component fixing groove is not suitable for covering the protective cover. By providing a rounded corner at the junction of the dielectric component fixing groove and the rib side wall, the multiphase flow velocity flowing through the dielectric component fixing groove is slowed down by the rounded corner, so as to reduce the impact of solid particles contained in the multiphase flow on the dielectric component.

[0015] Preferably, the ribs are arranged in a spiral shape on the outer wall of the main body, and the spiral angle is 30°.

[0016] Further preferably, the positive electrode and the negative electrode on both sides of the flow slot are located in the same horizontal plane, and the sound wave transmitting device and the sound wave receiving device on both sides of the flow slot are located in the same horizontal plane.

[0017] Preferably, the outer wall of the main body is provided with 6 fins, and the dielectric component and the acoustic wave component are each provided with 6 groups.

[0018] The working principle of the present invention is as follows: the centralizer plays a role in supporting the well wall during the drilling process, the outer wall of the fin is close to the well wall, and the multiphase flow generated underground can only flow upward through the flow groove when passing through the centralizer during the rising process. At this time, the monitoring device can accurately monitor whether there are bubbles in the fluid. Among them, the transmitting and receiving devices of the acoustic wave component perform acoustic wave monitoring on the multiphase flow, and the positive and negative electrodes of the dielectric component perform electric field monitoring on the multiphase flow.

[0019] The present invention also provides a method for using the acoustic-electric coupled downhole drilling intrusion monitoring device, comprising the following steps:

[0020] S1. Determine the formation conditions, simulate the downhole invasion conditions, and obtain the acoustic signal change trend diagram and the dielectric signal change trend diagram under each invasion condition;

[0021] S2. Put the downhole intrusion monitoring device into the well to conduct real-time monitoring of acoustic signals and dielectric signals.

[0022] Preferably, the method of use further comprises:

[0023] S3. When an intrusion occurs, the type and amount of intrusion are determined based on the measured changes in the acoustic signal and the dielectric signal;

[0024] S31. If the acoustic signal does not change but the dielectric signal changes, it is determined that dissolved gas intrusion has occurred, and the intrusion amount can be obtained by querying the dielectric signal change trend chart;

[0025] S32. If the acoustic signal changes and the dielectric signal also changes, it is preliminarily determined to be gas intrusion. The intrusion amount is determined based on the corresponding acoustic signal change trend graph. If the measured dielectric signal value is consistent with the dielectric signal under the intrusion amount in the dielectric signal change trend graph, it is determined to be gas intrusion. If they are inconsistent, it is determined to be rock chip intrusion. The intrusion amount is based on the intrusion amount determined by the dielectric signal change trend graph corresponding to the measured dielectric signal value.

[0026] Preferably, in step S1, the formation conditions include temperature and pressure, and the invasion conditions include gas invasion, dissolved gas invasion and rock debris invasion.

[0027] The working mechanism of the monitoring device provided by the present invention is as follows:

[0028] When the multiphase flow contains bubbles, the amplitude of the signal received by the acoustic wave receiving device will change. At the same time, the different bubble contents will cause the dielectric constant of the multiphase flow to change, so that the electric field generated by the dielectric component measures signals of different amplitudes; when the multiphase flow contains solid particles such as rock cuttings, the amplitude of the signal received by the acoustic wave receiving device will also change. Therefore, the acoustic wave component alone cannot accurately identify the difference between solid particles such as rock cuttings and bubbles. At the same time, the increase of solid particles such as rock cuttings will also cause the dielectric constant of the multiphase flow to change. However, since the dielectric properties of solid particles such as rock cuttings and bubbles are quite different, when solid particles such as rock cuttings and bubbles flow through the detection device respectively, the signals received by the dielectric component will change, but the changes are different; when the multiphase flow contains bubbles in a dissolved state, the amplitude of the signal received by the acoustic wave receiving device will not change, but the bubbles in a dissolved state will cause the dielectric constant of the multiphase flow to change, so that the electric field generated by the dielectric component measures signals of different amplitudes; therefore, the changes in the signals received by the dielectric component and the acoustic wave component can be used to determine the intrusion state at the bottom of the well.

[0029] Beneficial effects of the present invention:

[0030] 1. The monitoring device provided by the present invention replaces the traditional single-function centralizer with a centralizer with a monitoring unit, which does not need to occupy the limited underground space, and effectively overcomes the influence of complex underground conditions on the monitoring unit and the monitoring effect. The centralizer is lowered and raised together with the drill pipe. After the monitoring is completed during the drilling process, it can be removed and installed at the next drilling site to be monitored. The monitoring device can be used repeatedly.

[0031] 2. In the monitoring device provided by the present invention, the monitoring devices in the monitoring unit, namely the positive and negative electrodes of the dielectric component and the transmitting and receiving devices of the acoustic wave device, are respectively fixed on the side walls of the ribs on both sides of the same flow slot. Compared with the existing monitoring device, the spacing between the monitoring devices is effectively reduced, ensuring that the measured data is more accurate.

[0032] 3. In the monitoring device provided by the present invention, an acoustic wave component protection cover and rounded corners are provided to protect the acoustic wave component and the dielectric component respectively, thereby effectively controlling the damage of solid particles in the multiphase flow to the monitoring device, and extending the overall service life and maintenance cost of the device.

[0033] 4. During use of the monitoring device provided by the present invention, the dielectric component and the acoustic wave component cooperate with each other. Compared with the traditional acoustic wave gas intrusion detection device, the ability to identify solid particles such as rock cuttings is enhanced, and the accuracy of identifying gas intrusion is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic structural diagram of the acoustic-electric coupled downhole drilling intrusion monitoring device provided in Example 1;

[0035] Figure 2 It is a dimensional diagram of the acoustic-electric coupled downhole drilling intrusion monitoring device provided in Example 1;

[0036] Figure 3 This is a monitoring principle diagram of the acoustic-electric coupled downhole drilling intrusion monitoring device provided in Example 1;

[0037] Figure 4 is a trend diagram of acoustic wave signal changes under different intrusion amounts of gas intrusion provided in Example 2;

[0038] Figure 5 is a trend diagram of acoustic wave signals of rock fragments invasion with different intrusion amounts provided in Example 2;

[0039] Figure 6 is a graph showing a change trend of a dielectric signal under different intrusion amounts of gas intrusion provided in Example 2;

[0040] Figure 7 is a trend diagram of dielectric signal changes under different amounts of dissolved gas intrusion provided in Example 2;

[0041] Figure 8 This is a trend diagram of dielectric signal changes for different intrusion amounts of rock fragments provided in Example 2.

[0042] Among them, 1. dielectric component; 2. acoustic wave component fixing groove; 3. acoustic wave component; 4. flow groove; 5. dielectric component fixing groove; 6. rib. DETAILED DESCRIPTION

[0043] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0044] Example 1

[0045] An acoustic-electric coupling downhole intrusion monitoring device, such as Figure 1 As shown, it includes a centralizer and a monitoring unit, the centralizer includes a main body and fins 6, the main body is cylindrical, the fins 6 are arranged on the outer wall of the main body in parallel along the circumferential direction, and flow grooves 4 are formed between adjacent fins 6;

[0046] The monitoring unit includes a dielectric component 1, an acoustic wave component 3 and a signal processing device, wherein the dielectric component 1 includes a positive electrode and a negative electrode, and the acoustic wave component 3 includes an acoustic wave transmitting device and an acoustic wave receiving device. The positive electrode and the negative electrode are respectively fixed on the side walls of the ribs 6 on both sides of the flow slot 4, and the acoustic wave transmitting device and the acoustic wave receiving device are respectively fixed on the side walls of the ribs 6 on both sides of the flow slot 4. The signal processing device is electrically connected to the positive electrode, the negative electrode, the acoustic wave transmitting device and the acoustic wave receiving device, respectively. In this embodiment, the signal processing device is connected to the dielectric component and the acoustic wave component by cable transmission, and the signal processing device is used to receive signals from the positive electrode, the negative electrode, the acoustic wave transmitting device and the acoustic wave receiving device and process them to obtain monitoring information.

[0047] The side wall of the rib 6 is provided with a dielectric component fixing groove 5 and an acoustic wave component fixing groove 2 .

[0048] The side wall of the rib 6 is also fixed with an acoustic wave component protection cover, and the acoustic wave component protection cover completely covers the acoustic wave component fixing groove 2.

[0049] A fillet is provided at the junction of the dielectric component fixing groove 5 and the side wall of the rib 6. An electric field is generated between the positive and negative electrodes of the dielectric component 1 for monitoring, and there must be no obstacles or protective covers between the two to ensure the monitoring accuracy. Therefore, the dielectric component fixing groove 5 is not suitable for covering the protective cover. By providing a fillet at the junction of the dielectric component fixing groove 5 and the side wall of the rib 6, the multiphase flow velocity flowing through the dielectric component fixing groove 5 is slowed down by the fillet, so as to reduce the impact of solid particles contained in the multiphase flow on the dielectric component 1.

[0050] The ribs 6 are arranged on the outer wall of the main body in a spiral shape, and the spiral angle is 30°.

[0051] The positive electrode and the negative electrode on both sides of the flow slot 4 are located in the same horizontal plane, the sound wave transmitting device and the sound wave receiving device on both sides of the flow slot 4 are located in the same horizontal plane, and the left and right relative positions of the positive electrode, the negative electrode and the sound wave generating device and the sound wave receiving device can be set as needed.

[0052] The outer wall of the main body is provided with six fins 6, and the dielectric component 1 and the acoustic wave component 3 are each provided with six groups.

[0053] like Figure 2 As shown, in this embodiment, the monitoring device is applied to 8 1 / 2 in (215.9mm) borehole, generally the target layer can be drilled after two or three openings during the drilling process. Downhole gas invasion generally occurs after two or three openings, so this embodiment selects 8 1 / 2 in is an example. After multiple structural optimizations, the structural dimensions of the centralizer with the best monitoring effect are as follows:

[0054] The maximum outer diameter is 210mm, the vertical length is 190mm, there are 6 ribs 6, each rib 6 is 53mm wide and 30mm high, the spiral angle is set to 30° based on the plumb line, the upper and lower chamfers are 60°, and the flow groove 4 is 20mm wide; the acoustic wave component fixing groove 5 is cylindrical, with a diameter of 10mm and a depth of 15mm; the dielectric component fixing groove 2 is semi-cylindrical and bent toward the inside of the rib 6, with a radius of 10mm, a width of 10mm along the protruding direction of the rib, and a fillet of 3mm; the acoustic wave component fixing groove 5 and the dielectric component fixing groove 2 are both located in the middle position of the protruding direction of the rib 6.

[0055] like Figure 3 As shown, the centralizer supports the well wall during the drilling process, and the outer wall of the fin 6 is close to the well wall. The multiphase flow generated underground can only flow upward through the flow groove 4 when passing through the centralizer during the rising process. At this time, the monitoring device can accurately monitor whether there are bubbles in the fluid. Among them, the transmitting and receiving devices of the acoustic wave component 3 perform acoustic wave monitoring on the multiphase flow, and the positive and negative electrodes of the dielectric component 1 perform electric field monitoring on the multiphase flow.

[0056] Example 2

[0057] A method for using the acoustic-electric coupled downhole intrusion monitoring device provided in Example 1. In this embodiment, the formation conditions are 50° C. and 10 MPa. The method for using the device specifically includes the following steps:

[0058] S1. Determine the formation conditions, simulate the downhole invasion conditions, and obtain the acoustic signal change trend diagram and the dielectric signal change trend diagram under each invasion condition;

[0059] In this embodiment, COMSOL software is used for simulation. For the acoustic field simulation, the flow slot and the acoustic wave component are modeled, an acoustic wave transmitting device is set on the relatively left side of the flow slot, and an ultrasonic excitation signal is established at the acoustic wave transmitting device. An acoustic wave receiving device is set on the relatively right side of the same flow slot to receive the ultrasonic signal. The type and content of the medium flowing through the flow slot are changed by COMSOL software to obtain the acoustic signal change trend diagram under various intrusion conditions, as shown in FIG. Figure 4 and Figure 5As shown in the figure, they are the acoustic wave signal variation trend diagrams under different intrusion amounts of gas invasion and the acoustic wave signal variation trend diagrams under different intrusion amounts of rock debris invasion. For the electric field simulation, the same modeling and excitation process as the acoustic field simulation is used to obtain the following Figures 6 to 8 The dielectric signal variation trend diagram under gas invasion, the dielectric signal variation trend diagram under dissolved gas invasion and the dielectric signal variation trend diagram under rock debris invasion are shown;

[0060] S2. Put the downhole intrusion monitoring device into the well to conduct real-time monitoring of acoustic signals and dielectric signals;

[0061] S3. When an intrusion occurs, the type and amount of intrusion are determined based on the measured changes in the acoustic signal and the dielectric signal;

[0062] S31. If the acoustic signal does not change but the dielectric signal changes, it is determined that dissolved gas intrusion has occurred, and the intrusion amount can be obtained by querying the dielectric signal change trend chart;

[0063] S32. If the acoustic signal changes and the dielectric signal also changes, it is preliminarily determined to be gas intrusion. The intrusion amount is determined based on the corresponding acoustic signal change trend graph. If the measured dielectric signal value is consistent with the dielectric signal under the intrusion amount in the dielectric signal change trend graph, it is determined to be gas intrusion. If they are inconsistent, it is determined to be rock chip intrusion. The intrusion amount is based on the intrusion amount determined by the dielectric signal change trend graph corresponding to the measured dielectric signal value.

Claims

1. A method for using an acoustic-electric coupled downhole intrusion monitoring device, comprising the following steps: S1. Determine the formation conditions, simulate the downhole invasion conditions, and obtain the acoustic signal change trend diagram and the dielectric signal change trend diagram under each invasion condition; S2. Put the downhole intrusion monitoring device into the well to perform real-time monitoring of acoustic signals and dielectric signals; S3. When an intrusion occurs, the intrusion type and amount are determined according to the measured acoustic signal changes and dielectric signal changes; S31. If the acoustic signal does not change but the dielectric signal changes, it is determined that dissolved gas intrusion has occurred, and the intrusion amount can be obtained by querying the dielectric signal change trend chart; S32. If the acoustic signal changes and the dielectric signal also changes, it is preliminarily determined to be gas invasion. The invasion amount is determined based on the corresponding acoustic signal change trend graph. If the measured dielectric signal value is consistent with the dielectric signal corresponding to the invasion amount in the dielectric signal change trend graph, it is determined to be gas invasion. If they are inconsistent, it is determined to be rock chip invasion. The invasion amount is based on the invasion amount determined by the dielectric signal change trend graph corresponding to the measured dielectric signal value; In step S1, the formation conditions include temperature and pressure, and the invasion conditions include gas invasion, dissolved gas invasion and rock debris invasion; An acoustic-electric coupled downhole intrusion monitoring device for drilling comprises a centralizer and a monitoring unit, wherein the centralizer comprises a main body and fins, wherein the main body is cylindrical, the fins are arranged on the outer wall of the main body in parallel along the circumferential direction, and flow grooves are formed between adjacent fins; The monitoring unit includes a dielectric component, an acoustic wave component and a signal processing device, the dielectric component includes a positive electrode and a negative electrode, the acoustic wave component includes an acoustic wave transmitting device and an acoustic wave receiving device, the positive electrode and the negative electrode are respectively fixed on the rib side walls on both sides of the flow slot, the acoustic wave transmitting device and the acoustic wave receiving device are respectively fixed on the rib side walls on both sides of the flow slot, the signal processing device is electrically connected to the positive electrode, the negative electrode, the acoustic wave transmitting device and the acoustic wave receiving device, respectively, and the signal processing device is used to receive the signals of the positive electrode, the negative electrode, the acoustic wave transmitting device and the acoustic wave receiving device and process them to obtain monitoring information.

2. The method of use according to claim 1, characterized in that: The side wall of the fin is provided with a dielectric component fixing groove and an acoustic wave component fixing groove.

3. The method of use according to claim 2, characterized in that: The rib side wall is also fixed with an acoustic wave component protection cover, and the acoustic wave component protection cover completely covers the acoustic wave component fixing groove.

4. The method of use according to claim 2, characterized in that: A rounded corner is provided at the junction of the dielectric component fixing groove and the rib side wall.

5. The method of use according to claim 1, characterized in that: The ribs are arranged in a spiral shape on the outer wall of the main body, and the spiral angle is 30°.

6. The method of use according to claim 1, characterized in that: The positive pole and the negative pole on both sides of the flow slot are located in the same horizontal plane, and the sound wave transmitting device and the sound wave receiving device on both sides of the flow slot are located in the same horizontal plane.

7. The method of use according to claim 1, characterized in that: The outer wall of the main body is provided with 6 fins, and the dielectric component and the acoustic wave component are each provided with 6 groups.

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