Device and method for monitoring rotating speed of rotating nozzle under adjustable confining pressure condition

Abstract

The invention relates to the technical field of oil and gas well downhole tool tests, and discloses a rotating nozzle rotating speed monitoring device under an adjustable confining pressure condition, which comprises a confining pressure adjusting assembly, the confining pressure adjusting assembly comprises a non-magnetic shell and a non-magnetic short circuit, one end of the non-magnetic shell is provided with a sealing connecting piece, and the other end of the non-magnetic shell is provided with a nozzle seat; the nozzle seat is mounted between the non-magnetic outer shell and the non-magnetic short circuit through threads, and a nozzle seat inner shell is detachably connected with a nozzle; the rotating speed signal acquisition module comprises a rotating assembly located in the non-magnetic short circuit and an acquisition assembly located on the outer side of the non-magnetic shell; and the data processing module is electrically connected with the acquisition assembly. The problems that the rotating speed is difficult to directly obtain under the confining pressure environment, and the influence of the confining pressure on the rotating efficiency and the cutting / cleaning performance of the nozzle cannot be quantitatively analyzed are solved, and a basis is provided for structural design and process optimization of a rotating tool.

Description

Technical Field

[0001] This invention relates to the field of downhole tool testing and measurement technology for oil and gas wells, and in particular to a device and method for monitoring the rotational speed of a rotating nozzle under adjustable confining pressure. Background Technology

[0002] Rotary nozzle cutting or cleaning tools are widely used in coiled tubing cutting and cleaning operations in oil and gas wells. Experiments show that when tested under surface conditions without confining pressure, rotary nozzles can generally maintain a high and stable rotational speed, resulting in fast cutting speeds, smooth cut surfaces, and good cutting effects. However, in actual downhole operations, due to the high confining pressure at the well bottom, the rotational efficiency of the rotary nozzle decreases significantly, the cut surface becomes rough, and the cutting or wellbore cleaning quality declines significantly.

[0003] Field operations and experimental analysis revealed that changes in confining pressure significantly affect the rotational state of the rotary nozzle, particularly its rotational speed and stability. However, under current technological conditions, the actual rotational speed of the rotary nozzle in a confining pressure environment cannot be directly obtained, and effective monitoring methods are lacking. This makes it impossible to accurately analyze the relationship between confining pressure and the rotational speed and cutting performance of the rotary nozzle.

[0004] Existing technical solutions mainly fall into two categories, both of which have significant limitations and cannot meet the actual needs of rotating nozzle speed monitoring under confined pressure conditions. The first category is general sensor technology, which uses principles such as Hall effect, centrifugal force, and optical encoders to measure speed. Its design scenarios are atmospheric pressure or conventional industrial environments, and it is not specifically adapted to the special working conditions of oil and gas well downhole tool testing, such as high pressure, sealing, and complex fluid media. It also does not provide an engineering solution for anti-interference and non-contact real-time monitoring of high-speed rotating components inside a sealed confined pressure test cylinder, making it difficult to directly apply to the actual working performance testing of downhole rotating tools.

[0005] The second category comprises technologies related to downhole tools, focusing on the structural design, hydraulic performance optimization, and improvement of specific operating methods. These technologies generally lack quantitative and refined ground testing and evaluation methods for the dynamic performance of tools under confining pressure conditions. They also lack dedicated devices and standardized methods for simulating variable confining pressure and simultaneously monitoring core dynamic parameters. Performance evaluation of these tools often relies on costly and uncontrollable field tests, or only simple atmospheric pressure tests can be conducted. This fails to systematically reveal the inherent quantitative laws governing "confining pressure-tool dynamic speed-operating efficiency," severely restricting further structural optimization of rotary cutting tools and the precise design of process parameters.

[0006] To address this, a device and method for monitoring the rotational speed of a rotating nozzle under adjustable confining pressure is proposed. Summary of the Invention

[0007] The purpose of this invention is to provide a device and method for monitoring the rotational speed of a rotary nozzle under adjustable confining pressure, aiming to solve or improve at least one of the above-mentioned technical problems.

[0008] To achieve the above objectives, the present invention provides the following solution: The present invention provides a rotating nozzle rotation speed monitoring device under adjustable confining pressure conditions, comprising... A confining pressure regulating assembly includes a non-magnetic housing and a non-magnetic short circuit. A sealing connector is provided at one end of the non-magnetic housing. The sealing connector is threadedly installed between the non-magnetic housing and the non-magnetic short circuit. An upper connector is provided inside the sealing connector. A nozzle seat is provided at the other end of the non-magnetic housing. The nozzle seat is threadedly installed between the non-magnetic housing and the non-magnetic short circuit. A nozzle is detachably connected to the inner shell of the nozzle seat. A rotational speed signal acquisition module, comprising a rotating component located within the non-magnetic short circuit and an acquisition component located outside the non-magnetic housing; A data processing module is electrically connected to the acquisition component and is used to process the data acquired by the speed signal acquisition module.

[0009] Preferably, the rotating assembly includes a centralizer fixedly installed within the non-magnetic short circuit. The centralizer has a hollow structure, and one end of the centralizer is rotatably connected to a spray head, the spray head having a spray nozzle installed inside.

[0010] Preferably, the acquisition component includes a strong magnetic steel block fixedly installed on the nozzle, a Hall element installed on the side wall of the non-magnetic outer shell, the Hall element being correspondingly arranged with the strong magnetic steel block, and the Hall element being electrically connected to a data acquisition system.

[0011] Preferably, the data processing module includes a data processing computer, which is electrically connected to the data acquisition system.

[0012] Preferably, a pressure tapping channel is provided on the nozzle seat along its radial direction, and a pressure gauge is threadedly connected to the nozzle seat. The mounting port of the pressure gauge is connected to the pressure tapping channel. The end of the pressure tapping channel away from the pressure gauge is connected to the upstream main channel or pressure chamber of the nozzle. A damping orifice, a throttling orifice, or a buffer chamber is provided in the pressure tapping channel.

[0013] Preferably, the nozzle seat is threaded with an internal threaded connector at one end away from the non-magnetic outer shell, and the internal threaded connector is threaded with a discharge pipeline communicating with the lower tubing at one end away from the nozzle seat. The nozzle and the discharge pipeline are respectively arranged.

[0014] A method for monitoring the rotational speed of a rotating nozzle under adjustable confining pressure includes the following steps: Step 1: Assembly and connection check of the device; Seal and connect the upper connector, sealing connector, non-magnetic shell, non-magnetic short circuit, nozzle seat, nozzle, and discharge pipeline in sequence, check the sealing performance and flow continuity of the device, and confirm that the pressure gauge, Hall element, data acquisition system and data processing computer are working properly. Step 2, installation of the speed signal acquisition module; fix a strong magnet block on the outer surface of the nozzle; install a Hall element on the inner wall of the non-magnetic shell and adjust the radial gap between the Hall element and the strong magnet block; Step 3, confining pressure setting and stabilization; inject high-pressure fluid into the upper connector, place the device into the confining pressure test cylinder, increase the internal confining pressure by injecting fluid into the upper connector, and adjust the internal confining pressure by throttling the nozzle. The confining pressure can be adjusted by changing the nozzle specification or changing the throttling opening, and enter the data collection stage after the pressure stabilizes. Step 4, Data Acquisition and Processing: High-pressure fluid is continuously supplied to drive the nozzle to rotate. Simultaneously, the electrical signal output by the Hall element and the pressure signal from the pressure gauge are acquired through the data acquisition system to obtain data on the changes in voltage, current, and magnetic flux over time, and to obtain the electrical signal sequence and confining pressure data that change over time. The acquired electrical signals are filtered, shaped, and denoised using a data processing computer. The periodic characteristics of the signals are extracted and the main frequency is statistically analyzed. Combined with the number of strong magnetic steel blocks, the real-time rotational speed of the nozzle is calculated, and the stability index of the rotational speed is output. Step 5: Multi-containment pressure test and pattern analysis; change nozzles of different specifications to adjust the confining pressure value, repeat steps 3 and 4, complete the speed monitoring under different confining pressure conditions, form a confining pressure-speed-stability dataset, and analyze the influence of confining pressure on the rotation efficiency and operation effect of the nozzle based on the dataset.

[0015] Preferably, in step three, the nozzle specifications include 4mm, 4.5mm and 5mm. By changing the nozzle with different inner diameters, the confining pressure adjustment of 8MPa to 32MPa can be achieved within the theoretical flow range of 150L / min to 190L / min.

[0016] Preferably, the stability indicators in step four include average rotational speed, peak-to-peak fluctuation, and standard deviation data.

[0017] The present invention discloses the following technical effects: This invention is a confining pressure regulating component that forms a stable back pressure by throttling the nozzle. By changing nozzles of different diameters, it can achieve precise adjustment of the confining pressure in stages. With the pressure gauge at the nozzle seat, it can monitor and provide feedback on the pressure status in real time. It can stably simulate different levels of confining pressure conditions in the well, and solves the problems of uncontrollable confining pressure simulation and disconnect between the working conditions and the actual situation in the well in the existing tests. It provides a practical test basis for speed monitoring.

[0018] By employing a non-contact speed signal acquisition method that combines a strong magnetic steel block with a Hall element, real-time monitoring of nozzle speed is achieved under high-pressure sealed confining pressure. This overcomes the limitation that general-purpose sensors cannot achieve engineering monitoring under special working conditions in oil and gas well testing. The non-contact design avoids physical contact with high-speed rotating parts, ensuring the stability of the monitoring process.

[0019] The application of non-magnetic materials, including a non-magnetic shell and a non-magnetic short circuit, completely eliminates magnetic field interference from metal materials. The centralizer structure keeps the injection head rotating in the center, reducing signal fluctuations caused by eccentricity and significantly improving the accuracy and reliability of speed monitoring data. This solves the problems of large signal interference and low data accuracy in existing monitoring methods.

[0020] Based on this device and method, core data such as nozzle rotation speed and stability under multiple confining pressure conditions can be obtained, and a quantitative relationship between confining pressure, rotation speed and operating efficiency can be established. This replaces high-cost field tests and simple atmospheric pressure tests, and provides direct experimental basis for the structural improvement of rotary nozzle tools and the precise design of process parameters, effectively promoting the performance upgrade of downhole rotary tools. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the monitoring device structure of the present invention; Figure 2 This is a schematic diagram showing the interaction between the centralizer and the injection head. Figure 3 This is a schematic diagram showing the assembly of the nozzle and the spray head of the present invention; Figure 4 This is a schematic diagram of the sealing connector structure of the present invention; Figure 5 This is a schematic diagram of the nozzle structure of the present invention; Figure 6 This is a schematic diagram of the internal threaded connector structure of the present invention; Figure 7 This is a line graph of the rotational speed detection output data of the present invention.

[0023] The components include: 1. Upper connector; 2. Sealing connector; 3. Non-magnetic housing; 4. Non-magnetic short circuit; 5. Computer processing system; 6. Data processing computer; 7. Hall element; 8. Nozzle seat; 9. Pressure gauge; 10. Nozzle; 11. Discharge pipeline; 12. Internal threaded connector; 13. Spray head; 14. Strong magnetic steel block; 15. Centralizer. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Reference Figures 1-7 This invention provides a device for monitoring the rotational speed of a rotating nozzle under adjustable confining pressure, comprising: The confining pressure regulating assembly includes a non-magnetic housing 3 and a non-magnetic short-circuit 4. A sealing connector 2 is provided at one end of the non-magnetic housing 3, and the sealing connector 2 is threadedly installed between the non-magnetic housing 3 and the non-magnetic short-circuit 4. The threaded connection achieves a high-pressure sealing connection, creating a pressure-bearing and sealable pressure boundary within the internal space of the non-magnetic housing 3. An upper connector 1 is provided inside the sealing connector 2. A nozzle seat 8 is provided at the other end of the non-magnetic housing 3, and the nozzle seat 8 is threadedly installed between the non-magnetic housing 3 and the non-magnetic short-circuit 4. A nozzle 10 is detachably connected to the inner shell of the nozzle seat 8. The nozzle 10 throttles the outlet fluid, causing a pressure drop at the outlet and forming a stable back pressure upstream of the nozzle, which is the confining pressure condition that the device needs to simulate.

[0027] The rotation speed signal acquisition module includes a rotating component located inside the non-magnetic short circuit 4 and an acquisition component located outside the non-magnetic housing 3. The data processing module is electrically connected to the acquisition component and is used to process the data acquired by the speed signal acquisition module.

[0028] This invention provides a device and method for non-contact real-time monitoring of the actual rotational speed of a rotating nozzle 13 (or rotating cutting / cleaning nozzle assembly) under surface confining pressure test conditions. It establishes confining pressure conditions by creating a controllable back pressure through a throttling nozzle 10, achieving adjustable and high-precision simulation of downhole confining pressure conditions and providing stable experimental conditions for nozzle performance testing. A non-magnetic outer shell 3 and demagnetizing tubing are used to eliminate interference from metallic materials on the magnetic field signal, ensuring the accuracy of the measurement data. Furthermore, by setting magnetic elements on the rotating nozzle 13 and arranging Hall sensors outside the pressure boundary (or within the non-magnetic isolation cavity), the non-contact magnetoelectric conversion principle of the magnetic elements and Hall sensors is utilized to collect periodic magnetic field change signals. This allows for real-time acquisition of nozzle rotational speed and its stability data under confining pressure conditions, solving the problem of difficulty in directly obtaining rotational speed and quantitatively analyzing the impact of confining pressure on nozzle rotational efficiency and cutting / cleaning performance under confining pressure conditions. This provides a basis for the structural design and process optimization of rotating tools.

[0029] Furthermore, the upper connector 1 is a hollow connector, serving as the inlet interface between the external liquid supply or testing system and the interior of the device, through which fluid enters the device. Its lower end connects to the sealing connector 2, enabling the connection between the device and the lower injection system.

[0030] Furthermore, the non-magnetic outer shell 3 has a cylindrical structure and is made of non-magnetic material. It can accommodate the Hall element 7 and its related signal transmission components, thus avoiding interference from external magnetic fields in the acquisition of rotation speed signals.

[0031] Furthermore, the non-magnetic short circuit 4 is a hollow tubular structure, with its upper end connected to the sealing connector 2 and its lower end connected to the nozzle seat 8, used to transport high-pressure fluid to the injection head 13. The non-magnetic short circuit 4 needs to be demagnetized or made of non-magnetic materials in the experimental section to reduce magnetic field interference.

[0032] Further optimizing the design, the rotating assembly includes a centralizer 15 fixedly installed within the non-magnetic short-circuit 4. The centralizer 15 has a hollow structure, and one end of the centralizer 15 is rotatably connected to a jet head 13, which contains jet nozzles. There are at least two jet nozzles, symmetrically arranged about a center, with the nozzle axes not coinciding with the radius of the jet head 13. High-pressure fluid forms a jet stream through the jet nozzles, using the reaction force to drive the jet head 13 to rotate, thereby performing rotary cutting of the oil pipe. The centralizer 15, being hollow and connected to the jet head 13, keeps the jet head 13 centered within the non-magnetic short-circuit 4, reducing eccentric rotation of the jet head 13 during rotary cutting and improving measurement stability.

[0033] Further optimization of the scheme involves a data acquisition component including a strong magnetic steel block 14 fixedly mounted on the nozzle 13. The strong magnetic steel block 14 moves with the nozzle 13, thereby creating a periodic magnetic field change at the Hall element 7. A Hall element 7 is mounted on the side wall of the non-magnetic housing 3, corresponding to the strong magnetic steel block 14. The Hall element 7 is electrically connected to a data acquisition system. The data acquisition system receives the electrical signal output by the Hall element 7 and transmits the signal to the computer processing system 5. The Hall element 7, installed inside the non-magnetic housing 3, can sense the magnetic field change signal generated by the strong magnetic steel block 14 rotating with the nozzle.

[0034] The scheme has been further optimized, with the data processing module including a data processing computer 6, which is electrically connected to the data acquisition system. It is capable of processing, analyzing, and displaying the acquired speed signals.

[0035] To further optimize the design, a pressure tapping channel is provided on the nozzle seat 8 along its radial direction. A pressure gauge 9 is threadedly connected to the nozzle seat 8, and the mounting port of the pressure gauge 9 is connected to the pressure tapping channel. The end of the pressure tapping channel away from the pressure gauge 9 is connected to the upstream main channel or pressure chamber of the nozzle 10. A damping orifice, throttling orifice, or buffer chamber is provided in the pressure tapping channel to reduce the impact of pressure pulsation on the readings of the pointer gauge or sensor, and to avoid high-frequency fluctuations caused by nozzle throttling that lead to reading jitter. Through the pressure tapping hole of the nozzle seat 8 connected to the main channel, the upstream pressure of the nozzle 10 is displayed in real time. This pressure is used to characterize and monitor whether the current confining pressure condition has reached the target and whether it is stable.

[0036] Furthermore, the pressure gauge 9 and the nozzle seat 8 are preferably connected by a thread and a sealing structure is provided at the connection, and a gasket is used to achieve a pressure-resistant seal.

[0037] Furthermore, the nozzle 10 is a replaceable throttling element, located within the mounting cavity of the nozzle seat 8. The inner wall of the nozzle seat 8 forms a positioning step / limiting shoulder that matches the nozzle 10. The end face of the nozzle 10 abuts against the positioning step to achieve axial positioning, and the outer circle of the nozzle 10 mates with the inner hole of the nozzle seat 8 to achieve radial positioning. The downstream side of the nozzle is clamped and fixed by a downstream connector connected to the vent line 11, thereby preventing axial movement of the nozzle under high-pressure pulsating conditions.

[0038] Further optimization involves threaded connection of an internally threaded connector 12 to the end of the nozzle seat 8 furthest from the non-magnetic outer shell 3. The end of the internally threaded connector 12 furthest from the nozzle seat 8 is threaded to a discharge pipeline 11 connected to the lower tubing. The nozzle 10 is correspondingly positioned to the discharge pipeline 11. The internally threaded connector 12 is a hollow cylindrical structure with a through hole inside. It connects to the discharge pipeline 11 and the non-magnetic outer shell 3 via pipe threads, serving both connection and sealing functions. By comparing and analyzing rotational speed data under different confining pressure conditions, the variation law of the influence of confining pressure on the rotational speed of the rotary nozzle can be obtained, providing experimental basis for the subsequent structural design and process optimization of the rotary cutting tool.

[0039] The present invention sets up a nozzle throttling and pressure regulating structure in the confining pressure test device, and adjusts the confining pressure by changing the diameter of the nozzle 10, thereby establishing a correspondence between the confining pressure and the parameters of the nozzle 10.

[0040] Specifically, after the high-pressure fluid enters the injection head 13 through the tubing, it is discharged through the nozzle throttling device installed in the nozzle seat 8. Different nozzle diameters result in variations in outlet flow rate and pressure drop, thus creating stable environments with different confining pressures within the test chamber. By selecting different nozzle sizes 10 (e.g., 4mm, 4.5mm, 5mm), the confining pressure can be adjusted in stages to simulate different downhole confining pressure conditions. See the table below for details: Table 1. Experimental data on the effect of nozzle diameter on confining pressure regulation.

[0041] A method for monitoring the rotational speed of a rotating nozzle under adjustable confining pressure includes the following steps: Step 1: Assembly and connection check of the device; Seal and connect the upper connector 1, sealing connector 2, non-magnetic shell 3, non-magnetic short circuit 4, nozzle seat 8, nozzle 10, and discharge pipeline 11 in sequence, check the sealing performance and flow continuity of the device, and confirm that the pressure gauge 9, Hall element 7, data acquisition system and data processing computer 6 are working properly. Step 2, installation of the rotation speed signal acquisition module; fix the strong magnet 14 on the outer surface of the nozzle 13; install the Hall element 7 on the inner wall of the non-magnetic shell 3 and adjust the radial gap between the Hall element 7 and the strong magnet 14; Step 3, confining pressure setting and stabilization; inject high-pressure fluid into the upper connector 1, place the device into the confining pressure test cylinder, increase the internal confining pressure by injecting fluid into the upper connector 1, and adjust the internal confining pressure by throttling the nozzle. The confining pressure can be adjusted by changing the nozzle 10 specification or changing the throttling opening, and enter the sampling stage after the pressure stabilizes. Step 4, Data Acquisition and Processing: High-pressure fluid is continuously supplied to drive the nozzle 13 to rotate. At the same time, the electrical signal output by the Hall element 7 and the pressure signal of the pressure gauge 9 are synchronously acquired through the data acquisition system to obtain data on the changes of voltage, current and magnetic flux over time, and to obtain the electrical signal sequence and confining pressure data that change over time. The acquired electrical signal is filtered, shaped and denoised using the data processing computer 6, the periodic characteristics of the signal are extracted and the main frequency is statistically analyzed. Combined with the number of strong magnetic steel blocks 14, the real-time rotational speed of the nozzle 13 is calculated and the stability index of the rotational speed is output. Step 5: Multi-containment pressure test and pattern analysis; Replace nozzles 10 with different specifications to adjust the confining pressure value, repeat steps 3 and 4, complete the rotational speed monitoring under different confining pressure conditions, form a confining pressure-rotational speed-stability dataset, and analyze the influence of confining pressure on the rotational efficiency and working effect of the spray head 13 based on the dataset.

[0042] Further optimization of the scheme: In step three, the specifications of nozzle 10 include 4mm, 4.5mm and 5mm. By replacing nozzle 10 with different inner diameters, the confining pressure adjustment of 8MPa to 32MPa can be achieved within the theoretical flow range of 150L / min to 190L / min.

[0043] Further optimization of the scheme includes stability indicators such as average speed, peak-to-peak fluctuation, and standard deviation data in step four.

[0044] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0045] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A device for monitoring the rotational speed of a rotary nozzle under adjustable confining pressure, characterized in that: include A confining pressure regulating assembly includes a non-magnetic housing (3) and a non-magnetic short circuit (4). A sealing connector (2) is provided at one end of the non-magnetic housing (3). The sealing connector (2) is installed between the non-magnetic housing (3) and the non-magnetic short circuit (4) by threads. An upper connector (1) is provided inside the sealing connector (2). A nozzle seat (8) is provided at the other end of the non-magnetic housing (3). The nozzle seat (8) is installed between the non-magnetic housing (3) and the non-magnetic short circuit (4) by threads. A nozzle (10) is detachably connected to the inner shell of the nozzle seat (8). The rotation speed signal acquisition module includes a rotating component located inside the non-magnetic short circuit (4) and an acquisition component located outside the non-magnetic outer shell (3); A data processing module is electrically connected to the acquisition component and is used to process the data acquired by the speed signal acquisition module.

2. The adjustable confining pressure rotating nozzle rotation speed monitoring device according to claim 1, characterized in that: The rotating assembly includes a centralizer (15) fixedly installed in the non-magnetic short circuit (4). The centralizer (15) has a hollow structure. One end of the centralizer (15) is rotatably connected to a spray head (13). The spray head (13) has a spray nozzle installed inside.

3. The adjustable confining pressure rotating nozzle rotation speed monitoring device according to claim 2, characterized in that: The acquisition component includes a strong magnetic steel block (14) fixedly installed on the nozzle (13), and a Hall element (7) is installed on the side wall of the non-magnetic shell (3). The Hall element (7) is correspondingly arranged with the strong magnetic steel block (14), and the Hall element (7) is electrically connected to a data acquisition system.

4. The adjustable confining pressure rotating nozzle rotation speed monitoring device according to claim 3, characterized in that: The data processing module includes a data processing computer (6), which is electrically connected to the data acquisition system.

5. The adjustable confining pressure rotating nozzle rotation speed monitoring device according to claim 1, characterized in that: A pressure tapping channel is provided on the nozzle seat (8) along its radial direction. A pressure gauge (9) is threaded onto the nozzle seat (8). The mounting port of the pressure gauge (9) is connected to the pressure tapping channel. The end of the pressure tapping channel away from the pressure gauge (9) is connected to the upstream main channel or pressure chamber of the nozzle (10). A damping hole, a throttling hole, or a buffer chamber is provided in the pressure tapping channel.

6. The adjustable confining pressure rotating nozzle rotation speed monitoring device according to claim 1, characterized in that: The nozzle seat (8) is threaded with an internal thread connector (12) at one end away from the non-magnetic outer shell (3). The internal thread connector (12) is threaded with a discharge pipeline (11) communicating with the lower tubing at one end away from the nozzle seat (8). The nozzle (10) is set in correspondence with the discharge pipeline (11).

7. A method for monitoring the rotational speed of a rotary nozzle under adjustable confining pressure, based on the rotary nozzle rotational speed monitoring device under adjustable confining pressure as described in any one of claims 1-6, characterized in that, Includes the following steps: Step 1, device assembly and connection check; connect the upper connector (1), sealing connector (2), non-magnetic shell (3), non-magnetic short circuit (4), nozzle seat (8), nozzle (10), and discharge pipeline (11) in sequence, check the sealing performance and flow connectivity of the device, and confirm that the pressure gauge (9), Hall element (7), data acquisition system and data processing computer (6) are working normally; Step 2, installation of the rotation speed signal acquisition module; a strong magnetic steel block (14) is fixedly installed on the outer surface of the nozzle (13); a Hall element (7) is installed on the inner wall of the non-magnetic shell (3) and the radial gap between the Hall element (7) and the strong magnetic steel block (14) is adjusted; Step 3, setting and stabilizing confining pressure; inject high-pressure fluid into the upper connector (1), place the device into the confining pressure test cylinder, increase the internal confining pressure by injecting fluid into the upper connector (1), and adjust the internal confining pressure by throttling through the nozzle (10). The confining pressure is adjusted by changing the nozzle (10) specification or changing the throttling opening, and enter the sampling stage after the pressure stabilizes. Step 4, data acquisition and processing: High-pressure fluid is continuously introduced to drive the nozzle (13) to rotate. At the same time, the electrical signal output by the Hall element (7) and the pressure signal of the pressure gauge (9) are synchronously acquired through the data acquisition system to obtain the data of voltage, current and magnetic flux changing with time, and to obtain the electrical signal sequence and confining pressure data changing with time. The data processing computer (6) is used to filter, shape and denoise the acquired electrical signal, extract the periodic characteristics of the signal and count the main frequency. Combined with the number of strong magnetic steel blocks (14), the real-time rotation speed of the nozzle (13) is calculated and the stability index of the rotation speed is output. Step 5: Multi-containment pressure test and pattern analysis; Replace nozzles (10) of different specifications to adjust the containment pressure value, repeat steps 3 and 4, complete the speed monitoring under different containment pressure conditions, form a containment pressure-speed-stability dataset, and analyze the influence of containment pressure on the rotation efficiency and operation effect of the spray head (13) based on the dataset.

8. The method for monitoring the rotational speed of a rotary nozzle under adjustable confining pressure as described in claim 7, characterized in that: In step three, the specifications of the nozzle (10) include 4mm, 4.5mm and 5mm. By replacing the nozzle (10) with different inner diameters, the confining pressure adjustment of 8MPa to 32MPa can be achieved within the theoretical flow range of 150L / min to 190L / min.

9. The method for monitoring the rotational speed of a rotating nozzle under adjustable confining pressure as described in claim 7, characterized in that: The stability indicators in step four include average rotational speed, peak-to-peak fluctuation, and standard deviation data.

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