Device and method for measuring cementing strength of high-temperature and high-pressure well and thermal recovery well cement ring interface

Abstract

The application provides a high-temperature and high-pressure well and thermal recovery well cement sheath interface cementation strength measuring device and method, and relates to the field of oil and gas field exploration and development. A hydrothermal kettle, a casing pressure control system, a confining pressure control system, a first test system, a second test system and an acoustic variable density logging system are provided. The hydrothermal kettle comprises a kettle body. A formation model is arranged in the kettle body, and a casing is arranged in the model. The model and the kettle body form a confining pressure cavity, and the casing and the model form an annular structure for forming a cement sheath. The first and second interfaces are the interfaces of the cement sheath and the casing and the model. The casing pressure control system comprises first and second pipelines, and the first pipeline is connected with a heater. The confining pressure control system comprises third and fourth pipelines. The first test system comprises fifth, sixth, seventh and eighth pipelines. Pressure gauges are arranged on the pipelines. The second test system comprises first and second pressure sensors. The logging system comprises an ultrasonic assembly and an acoustic variable density logging instrument. The problem of incomplete cementation strength evolution of cementation surface under the conditions of high temperature and thermal recovery well circulation temperature is solved.

Description

Technical Field

[0001] This application relates to the field of oil and gas field exploration and development, and in particular to a device and method for measuring the bonding strength of the cement sheath interface in high-temperature and high-pressure wells and thermal recovery wells. Background Technology

[0002] The cement sheath bonding strength directly affects the sealing performance of cementing, wellbore stability, and the smooth operation of downhole work. Therefore, the cement sheath bonding strength is crucial for the lifespan and wellhead safety of oil and gas wells. Furthermore, the cement sheath bonding strength is closely related to the long-term safety and economic benefits of oil and gas wells, making the monitoring of cement sheath bonding strength under different operating conditions particularly important.

[0003] Existing technologies mainly focus on testing in ambient temperature wells. A cement sheath bond strength evaluation device based on ambient temperature wells has been developed, and tests on cement sheath bond strength under varying casing internal pressure conditions have been conducted. The measurement results of the cementing surface bond strength experiments have been reported. However, the evolution of cementing surface bond strength under high temperature conditions and thermal recovery well circulation temperature conditions is not comprehensive enough. Summary of the Invention

[0004] This application provides a device and method for measuring the bonding strength of the cement sheath interface in high-temperature and high-pressure wells and thermal recovery wells, in order to solve the technical problem that the existing technology does not fully cover the evolution of the bonding strength of the cementing surface under high-temperature conditions and thermal recovery well circulation temperature conditions.

[0005] In a first aspect, this application provides a device for measuring the bonding strength of the cement sheath interface in high-temperature and high-pressure wells and thermally recovered wells, comprising:

[0006] Hydrothermal reactor, casing pressure control system, confining pressure control system, first testing system, second testing system, and acoustic variable density logging system;

[0007] The hydrothermal reactor includes a reactor body; a formation model is installed inside the reactor body, and a sleeve is installed inside the formation model;

[0008] A confining pressure cavity is formed between the formation model and the vessel body, and an annular structure is formed between the casing and the formation model. The annular structure is used to form a cement sheath. The first interface of the cementing bonding surface is the interface between the cement sheath and the casing, and the second interface of the cementing bonding surface is the interface between the cement sheath and the formation model.

[0009] The sleeve pressure control system includes a first pipe and a second pipe, the first pipe being connected to a heater; the first pipe and the second pipe are used together to adjust the pressure applied to the sleeve.

[0010] The confining pressure control system includes a third pipe and a fourth pipe; the third pipe and the fourth pipe are used together to adjust the pressure applied to the confining pressure chamber;

[0011] The first testing system includes a fifth pipe, a sixth pipe, a seventh pipe, and an eighth pipe; the fifth pipe and the sixth pipe are used together to adjust the pressure applied to the first interface of the cementing surface, and the seventh pipe and the eighth pipe are used together to adjust the pressure applied to the second interface of the cementing surface.

[0012] Each of the aforementioned pipes is equipped with a pressure gauge;

[0013] The second testing system includes a first pressure sensor and a second pressure sensor; the first pressure sensor is used to monitor the pressure applied to the first interface of the cementing surface, and the second pressure sensor is used to monitor the pressure applied to the second interface of the cementing surface.

[0014] The acoustic variable density logging system includes an ultrasonic component and an acoustic variable density logging instrument, which are used together to detect the amplitude of the first wave of the casing inside the casing and to determine the cementing status of the cementing surface based on the amplitude.

[0015] In one possible design, the first pipeline is further equipped with a first constant speed and constant pressure pump and a first control valve, and the second pipeline is further equipped with a second control valve; the first pipeline is connected to the pressure storage tank through the heater, and the second pipeline is connected to the pressure storage tank.

[0016] In one possible design, the third pipeline is also equipped with a second constant speed and constant pressure pump and a third control valve, and the fourth pipeline is also equipped with a fourth control valve; the third pipeline is connected to the injection tank, and the fourth pipeline is connected to the waste liquid tank.

[0017] In one possible design, the fifth pipeline is also equipped with a third constant speed and constant pressure pump and a fifth control valve, and the sixth pipeline is also equipped with a sixth control valve; the fifth pipeline is connected to the first gas injection tank, and the sixth pipeline is connected to the first waste gas tank.

[0018] In one possible design, the seventh pipeline is also equipped with a fourth constant speed and constant pressure pump and a seventh control valve, and the eighth pipeline is also equipped with an eighth control valve; the seventh pipeline is connected to the second gas injection tank, and the eighth pipeline is connected to the second waste gas tank.

[0019] In one possible design, one end of each of the first pipe and the second pipe passes through the vessel body and is placed inside the pressure chamber, and the other end of each of the first pipe and the second pipe is connected to the pressure storage tank.

[0020] One end of each of the third and fourth pipes passes through the vessel body and is placed inside the confining pressure chamber. The other end of the third pipe is connected to the injection tank, and the other end of the fourth pipe is connected to the waste liquid tank.

[0021] One end of each of the fifth and sixth pipes passes through the vessel body and is placed within the annular structure. The other end of the fifth pipe is connected to the first gas injection tank, and the other end of the sixth pipe is connected to the first waste gas tank.

[0022] One end of each of the seventh and eighth pipes passes through the vessel body and is placed within the annular structure. The other end of the seventh pipe is connected to the second gas injection tank, and the other end of the eighth pipe is connected to the second waste gas tank.

[0023] In one possible design, the formation model is cylindrical in shape; a wellbore is located at the center of the formation model, and the casing is disposed within the wellbore;

[0024] An ultrasonic component is installed at the center of the casing, and the ultrasonic component is connected to an acoustic variable density logging tool; wherein, the ultrasonic component and the acoustic variable density logging tool are used together to measure the attenuation value and amplitude of the casing wave in the circumferential direction of the wellbore.

[0025] Secondly, this application provides a method for measuring the bonding strength of the cement sheath interface in high-temperature and high-pressure wells and thermal recovery wells. The method is used in the high-temperature and high-pressure well and thermal recovery well cement sheath interface bonding strength measuring device provided in the first aspect of this application. The device includes: a hydrothermal reactor and a casing pressure control system; wherein the hydrothermal reactor includes a reactor body, a formation model is disposed within the reactor body, and a casing is disposed within the formation model; the casing pressure control system includes a first pipe connected to a heater, and an annular structure is formed between the casing and the formation model, the annular structure being used to form a cement sheath; the first interface of the cementing bonding surface is the interface between the cement sheath and the casing, and the second interface of the cementing bonding surface is the interface between the cement sheath and the formation model, then the method includes:

[0026] The temperature conditions of the first pipeline are adjusted by the heater, and the hydraulic bonding strength of the first interface of the cementing surface, the hydraulic bonding strength of the second interface of the cementing surface, the mechanical bonding strength of the first interface of the cementing surface, and the mechanical bonding strength of the second interface of the cementing surface are tested under different temperature conditions; wherein, the temperature conditions include high temperature conditions and circulating temperature conditions, and the high temperature conditions are conditions higher than the preset temperature.

[0027] In one possible design, the device further includes a second testing system, wherein the first testing system in the device further includes a fifth pipe, a sixth pipe, a seventh pipe, an eighth pipe, and a pressure gauge disposed on each of the pipes; wherein the second testing system includes a first pressure sensor and a second pressure sensor;

[0028] The step of adjusting the temperature conditions of the first pipeline through the heater and testing the hydraulic bonding strength of the first interface, the hydraulic bonding strength of the second interface, the mechanical bonding strength of the first interface, and the mechanical bonding strength of the second interface of the cementing surface under different temperature conditions includes:

[0029] Record the initial reading of the pressure gauge on the fifth pipeline, apply pressure to the fifth pipeline, and stop applying pressure to the fifth pipeline when the reading of the pressure gauge on the sixth pipeline starts to increase. When the reading of the pressure gauge on the sixth pipeline is equal to the reading of the pressure gauge on the fifth pipeline, obtain the hydraulic bonding strength of the first interface of the cementing surface under the preset temperature based on the difference between the reading of the pressure gauge on the sixth pipeline and the reading of the pressure gauge on the fifth pipeline when the pressure increase value changed last time.

[0030] Record the initial reading of the pressure gauge on the seventh pipe, apply pressure to the seventh pipe, and stop applying pressure to the seventh pipe when the reading of the pressure gauge on the eighth pipe starts to increase. When the reading of the pressure gauge on the eighth pipe is equal to the reading of the pressure gauge on the seventh pipe, obtain the hydraulic bonding strength of the second interface of the cementing surface under the preset temperature based on the difference between the reading of the pressure gauge on the eighth pipe and the reading of the pressure gauge on the seventh pipe when the pressure increase value changed last time.

[0031] Pressure is applied to the casing, and the value of the first pressure sensor is observed in real time. When the cement sheath separates from the casing, the mechanical bonding strength of the first interface of the cementing surface is obtained under the preset temperature based on the value of the first pressure sensor when the pressure value changes last time.

[0032] Pressure is applied to the cement sheath, and the value of the second pressure sensor is observed in real time. When the cement sheath separates from the formation model, the mechanical bonding strength of the second interface of the cementing surface is obtained under the preset temperature based on the value of the second pressure sensor when the pressure value changes last time.

[0033] Specifically, the cement ring is obtained by injecting cement slurry into the annular structure; when the preset temperature value is determined according to the high temperature conditions, the curing temperature of the cement ring is set to the preset temperature value; when the preset temperature value is determined according to the circulating temperature conditions, the gas temperature in the first pipeline is adjusted to the preset temperature value by the heater.

[0034] In one possible design, the device further includes a first upper vessel cover and a second upper vessel cover, the second upper vessel cover having a recessed structure, the first upper vessel cover having a first injection port, a second injection port, a third injection port and a fourth injection port, and the second upper vessel cover having a fifth injection port and a sixth injection port.

[0035] Before obtaining the hydraulic bonding strength of the first interface of the cementing surface at the preset temperature, the method further includes:

[0036] Install the first upper vessel cover, and connect the first pipe, the third pipe, the fifth pipe and the seventh pipe to the first upper vessel cover through the first injection port, the second injection port, the third injection port and the fourth injection port respectively;

[0037] Before obtaining the mechanical bonding strength of the first interface of the cementing surface at the preset temperature, the method further includes:

[0038] Replace the first upper vessel cover with the second upper vessel cover, and connect the first pipe and the third pipe to the second upper vessel cover through the first injection port and the second injection port, respectively.

[0039] This application provides a device and method for measuring the bonding strength of the cement sheath interface in high-temperature, high-pressure wells and thermal recovery wells, comprising: a hydrothermal reactor, a casing pressure control system, a confining pressure control system, a first testing system, a second testing system, and an acoustic variable density logging system; the hydrothermal reactor includes a reactor body, a formation model is disposed within the reactor body, and a casing is disposed within the formation model; a confining pressure cavity is formed between the formation model and the reactor body, and an annular structure is formed between the casing and the formation model, the annular structure being used to form a cement sheath; the first interface of the cement bonding surface is the interface between the cement sheath and the casing, and the second interface of the cement bonding surface is the interface between the cement sheath and the formation model; the casing pressure control system includes a first pipe and a second pipe, the first pipe being connected to a heater; the confining pressure control system includes a third pipe and a fourth pipe; the first testing system includes a fifth pipe, a sixth pipe, a seventh pipe, and an eighth pipe; pressure gauges are installed on each pipe; the second testing system includes a first pressure sensor and a second pressure sensor; the acoustic variable density logging system includes an ultrasonic component and an acoustic variable density logging instrument, which are used together to detect the amplitude of the first wave of the casing wave inside the casing and to determine the bonding condition of the cement bonding surface based on the amplitude. Through the above structural design, the following technical effects are achieved: The first pipeline is connected to the heater. The temperature of the high-temperature gas injected into the first pipeline is adjusted using an electric heater. The temperature on the first pipeline is observed. Considering the actual temperature variation range of the wellbore in thermal recovery wells, the casing temperature is increased from the initial formation temperature to the corresponding wellbore temperature when hot steam is injected. Considering the actual well-closing time, the final wellbore temperature after closing, and the number of cycles, the system temperature reduction gradient, final temperature, and number of cycles are set to simulate the steam injection process of thermal recovery wells. This allows for the measurement of the cementing strength of the cemented surface in thermal recovery wells under multiple cycle temperature conditions, overcoming the limitation of existing equipment for measuring the cementing strength of thermal recovery wells, which cannot continuously measure mechanical or hydraulic cementing. The challenge of cement bond strength is addressed by simulating the effects of different temperatures and pressures on the cement bond strength of cemented surfaces under high-temperature and high-pressure conditions, based on the actual conditions of high-temperature and high-pressure gas wells. This allows for the measurement of cement bond strength under high-temperature conditions. The first testing system measures the hydraulic cement bond strength, while the second system measures the mechanical cement bond strength. By changing the testing systems, the mechanical cement bond strength can be measured under different temperature and pressure conditions, providing a basis for measuring the cement bond strength and solving the problem that existing cement bond performance testing equipment cannot meet the requirements for measuring mechanical cement bond strength under high-temperature and high-pressure conditions. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0042] Figure 1 Schematic diagram of the structure of the cement sheath interface bonding strength measuring device for high-temperature and high-pressure wells and thermal recovery wells provided in this application embodiment. Figure 1 ;

[0043] Figure 2 Schematic diagram of the structure of the cement sheath interface bonding strength measuring device for high-temperature and high-pressure wells and thermal recovery wells provided in this application embodiment. Figure 2 .

[0044] Figure label:

[0045] 100-Hydrothermal reactor; 110-Reactor body; 200-Containing pressure control system; 210-First pipeline; 2101-First constant speed and constant pressure pump; 2102-First control valve; 220-Second pipeline; 2201-Second control valve; 300-Containing pressure control system; 310-Third pipeline; 3101-Second constant speed and constant pressure pump; 3102-Third control valve; 320-Fourth pipeline; 3201-Fourth control valve; 400-First testing system; 410-Fifth pipeline; 41 01-Third constant speed and pressure pump; 4102-Fifth control valve; 420-Sixth pipeline; 4201-Sixth control valve; 430-Seventh pipeline; 4301-Fourth constant speed and pressure pump; 4302-Seventh control valve; 440-Eighth pipeline; 4401-Eighth control valve; 500-Second testing system; 510-First pressure sensor; 520-Second pressure sensor; 600-Sonic variable density logging system; 610-Ultrasonic component; 620-Sonic variable density logging tool; 710-Formation model; 720-Casing; 730-Containing pressure cavity; 740-Cement sheath; 750-First interface of cementing bonding surface; 760-Second interface of cementing bonding surface; 770-Heater; 810-Casing pressure gas storage tank; 820-Injection tank; 830-Waste liquid tank; 840-First injection tank; 850-First waste gas tank; 860-Second injection tank; 870-Second waste gas tank; 880-Casing pressure cavity; 910-Universal pressure testing machine; 920-Hydraulic press; 930-Upper cement sheath pressure sensor; 940-Lower cement sheath force transmission component; 950-Upper cement sheath force transmission component; 960-Casing force transmission component; 970-First upper cover; 980-Second upper cover; 990-Upper sealing ring; 991-Lower sealing ring. Detailed Implementation

[0046] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of the embodiments of this invention.

[0047] In the embodiments of this application, the terms "first" and "second" are used to distinguish identical or similar items with substantially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that "first" and "second" do not necessarily imply difference. It should be noted that in the embodiments of this application, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design scheme described as "exemplary" or "for example" in the embodiments of this application should not be construed as being better or more advantageous than other embodiments or design schemes. Specifically, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner. In the embodiments of this application, "at least one" refers to one or more, and "more than one" refers to two or more.

[0048] It should be noted that the phrase "at the moment when..." in the embodiments of this application can refer to the instant at which a certain situation occurs, or to a period of time after the occurrence of a certain situation; the embodiments of this application do not specifically limit this. Furthermore, the device for measuring the bonding strength of the cement sheath interface in high-temperature, high-pressure wells and thermally recovered wells provided in the embodiments of this application is merely an example; the device for measuring the bonding strength of the cement sheath interface in high-temperature, high-pressure wells and thermally recovered wells may also include more or fewer components.

[0049] First, the terms used in the embodiments of this application will be explained accordingly:

[0050] Cement sheath interface bonding strength: Cement sheath interface bonding strength refers to the bonding strength between the cement sheath and the casing interface and between the cement sheath and the simulated formation interface, including the hydraulic bonding strength and mechanical bonding strength of the cement sheath and the casing interface, as well as the hydraulic bonding strength and mechanical bonding strength of the cement sheath and the simulated formation interface.

[0051] The first interface of the cementing bonding surface: The hydrothermal reactor includes a reactor body, inside which a formation model is installed, and within the formation model is a casing. An annular structure is formed between the casing and the formation model. When measuring the cementing strength of the cementing surface, cement slurry is injected into the annular structure to obtain a cement sheath. The first interface of the cementing bonding surface is the interface between the cement sheath and the casing.

[0052] The second interface of the cementing bonding surface: The hydrothermal reactor includes a reactor body, inside which a formation model is installed, and a casing is installed inside the formation model. An annular structure is formed between the casing and the formation model. When measuring the cementing strength of the cementing bonding surface, cement slurry is injected into the annular structure to obtain a cement sheath. The second interface of the cementing bonding surface is the interface between the cement sheath and the formation model.

[0053] In order to clearly understand the technical solutions of the embodiments of this application, the solutions of the prior art will be described in detail first.

[0054] Existing technologies mainly focus on testing in ambient temperature wells. A cement sheath bond strength evaluation device based on ambient temperature wells has been developed, and tests on cement sheath bond strength under variable casing internal pressure conditions have been conducted, with relevant measurement results reported. However, the evolution of cement sheath bond strength under high temperature conditions and thermal recovery well circulation temperature conditions is not comprehensive enough.

[0055] Therefore, how to design a cement sheath interface bonding strength measuring device that can measure the bonding strength of cementing surfaces under high temperature conditions and thermal recovery well circulation temperature conditions is a problem that urgently needs to be solved in the embodiments of this application.

[0056] Therefore, in view of the above-mentioned technical problems existing in the prior art, the present application provides a device and method for measuring the bonding strength of cement sheath interface in high-temperature and high-pressure wells and thermal recovery wells, which can be used in the field of oil and gas field exploration and development, and is intended to measure the bonding strength of cementing surface under high temperature conditions and thermal recovery well circulation temperature conditions.

[0057] The following describes the application scenarios of a device and method for measuring the bonding strength of the cement sheath interface in high-temperature, high-pressure wells and thermal recovery wells, as provided in the embodiments of this application. These application scenarios are merely examples, intended to help those skilled in the art understand the technical content of the embodiments of this application, but do not imply that the embodiments of this application cannot be used in other devices, systems, environments, or scenarios.

[0058] 1) Oil and Gas Extraction: In the process of oil and gas extraction, especially in deep wells and high-temperature environments, cement sheaths are used to fix the wellbore and protect the pipeline. The bonding strength between the cement sheath and the well wall directly affects the stability of the cementing process. The apparatus provided in this application embodiment can measure the bonding strength between the cement sheath and the well wall, thereby analyzing the cementing effect, ensuring the stability of the wellbore, preventing wellbore collapse or fluid leakage, and guaranteeing the safety and efficiency of the oil and gas extraction process.

[0059] 2) Downhole operations in high-temperature environments: In some deep wells, geothermal wells, or deep oil and gas wells, downhole temperatures can reach hundreds of degrees Celsius. The bonding strength of cement sheaths may decrease with increasing temperature, making it crucial to test their performance under high-temperature conditions. The device provided in this application can simulate high-temperature environments under actual working conditions, thereby providing accurate bonding strength data to help optimize the selection of cementing materials and construction schemes.

[0060] 3) Circulating Temperature Conditions in Thermal Recovery Wells: During thermal recovery operations, such as the extraction of oil and gas and geothermal energy, the wellbore experiences circulating temperature changes. These temperature changes affect the bonding strength between the cement sheath and the wellbore, potentially leading to a decrease in bonding strength and consequently impacting cementing quality. The apparatus provided in this application embodiment can analyze changes in the bonding strength of the cement sheath under simulated circulating temperature conditions, thereby ensuring long-term stability during thermal recovery well operations.

[0061] 4) Cementing Quality Analysis and Repair: After the cementing process is completed, the bonding strength of the cement sheath in the well may be affected by factors such as temperature changes and pressure. Regularly using the device provided in the embodiments of this application can detect the bonding strength of the cement sheath, promptly identify defects in cementing quality, provide a basis for subsequent repair or reinforcement measures, and ensure the safety and effectiveness of downhole operations.

[0062] The embodiments of this application are described below with reference to the accompanying drawings.

[0063] Figure 1 Schematic diagram of the structure of the cement sheath interface bonding strength measuring device for high-temperature and high-pressure wells and thermal recovery wells provided in this application embodiment. Figure 1 , Figure 2 Schematic diagram of the structure of the cement sheath interface bonding strength measuring device for high-temperature and high-pressure wells and thermal recovery wells provided in this application embodiment. Figure 2 ,like Figure 1 and Figure 2 As shown in the embodiment of this application, a device for measuring the bonding strength of the cement sheath interface between a high-temperature, high-pressure well and a thermal recovery well is provided.

[0064] It includes a hydrothermal reactor 100, a casing pressure control system 200, a confining pressure control system 300, a first testing system 400, and a second testing system 500.

[0065] The hydrothermal reactor 100 includes a reactor body 110; a formation model 710 is installed inside the reactor body 110, and a casing 720 is installed inside the formation model 710.

[0066] In this embodiment, the vessel body 110 includes a cylindrical vessel wall and a lower vessel bottom. A formation model 710 is provided inside the vessel body 110, and a sleeve 720 is provided inside the formation model 710.

[0067] A confining pressure cavity 730 is formed between the formation model 710 and the vessel body 110, and an annular structure is formed between the casing 720 and the formation model 710. The annular structure is used to form the cement sheath 740. The first interface 750 of the cementing bonding surface is the interface between the cement sheath 740 and the casing 720, and the second interface 760 of the cementing bonding surface is the interface between the cement sheath 740 and the formation model 710.

[0068] In this embodiment, optionally, the outer wall of the formation model 710 is wrapped in a high-temperature resistant rubber sleeve, and the high-temperature resistant rubber sleeve and the inner wall of the vessel body 110 form a confining pressure cavity 730.

[0069] An annular structure is formed between the casing 720 and the formation model 710. When measuring the cementing strength of the cementing surface, the cement slurry used in the experiment is first prepared, and then the prepared cement slurry is injected into the annular structure to form a cement sheath 740. Among them, the interface between the cement sheath 740 and the casing 720 is the first interface 750 of the cementing surface, and the interface between the cement sheath 740 and the formation model 710 is the second interface 760 of the cementing surface.

[0070] The pressure control system 200 includes a first pipe 210 and a second pipe 220, with the first pipe 210 connected to the heater 770.

[0071] In this embodiment, the first pipe 210 and the second pipe 220 are used together to adjust the pressure applied to the sleeve 720.

[0072] Specifically, the casing pressure control system 200 is used to apply internal pressure to the casing 720, and includes a first pipe 210 and a second pipe 220, with the first pipe 210 connected to the heater 770. The first pipe 210 is the inlet pipe of the casing pressure control system 200, and the second pipe 220 is the outlet pipe. By injecting high-temperature, high-pressure gas into the first pipe 210, the pressure applied to the casing 720 can be adjusted. Two casing pressure sensors are installed to monitor the internal pressure of the casing 720.

[0073] The first pipeline is connected to a heater. The temperature of the high-temperature gas injected into the first pipeline is adjusted using an electric heater. The temperature on the first pipeline is observed. Considering the actual temperature variation range of the wellbore in the thermal recovery well, the casing temperature is increased from the initial formation temperature to the corresponding wellbore temperature when hot steam is injected. Considering the actual well-closing time, the final wellbore temperature after closing, and the number of cycles, the system temperature reduction gradient, final temperature, and number of cycles are set to simulate the steam injection process of the thermal recovery well. This allows for the measurement of the cementing strength of the cementing surface of the thermal recovery well under multiple cycle temperature conditions. This overcomes the problem that existing equipment for measuring the cementing strength of the cementing surface in thermal recovery wells cannot continuously measure the mechanical or hydraulic cementing strength.

[0074] The confining pressure control system 300 includes a third pipe 310 and a fourth pipe 320.

[0075] In this embodiment, the third pipe 310 and the fourth pipe 320 are used together to adjust the pressure applied to the confining pressure chamber 730.

[0076] Specifically, the confining pressure control system 300 is used to apply confining pressure and includes a third pipe 310 and a fourth pipe 320. The third pipe 310 is the inlet pipe of the confining pressure control system 300, and the fourth pipe 320 is the outlet pipe. By injecting high-pressure liquid into the third pipe 310, the pressure applied to the confining pressure chamber 730 can be adjusted. Two confining pressure sensors are installed to monitor the pressure applied to the confining pressure chamber 730.

[0077] The first test system 400 includes a fifth pipe 410, a sixth pipe 420, a seventh pipe 430, and an eighth pipe 440.

[0078] In this embodiment, the fifth pipe 410 and the sixth pipe 420 are used together to adjust the pressure applied to the first interface 750 of the cementing surface, and the seventh pipe 430 and the eighth pipe 440 are used together to adjust the pressure applied to the second interface 760 of the cementing surface.

[0079] Specifically, the first testing system 400 is used to measure the hydraulic bonding strength of the cementing surface, including a fifth pipe 410, a sixth pipe 420, a seventh pipe 430, and an eighth pipe 440. The fifth pipe 410 is the inlet pipe of the first interface 750 of the cementing surface, the sixth pipe 420 is the outlet pipe of the first interface 750, the seventh pipe 430 is the inlet pipe of the second interface 760, and the eighth pipe 440 is the outlet pipe of the second interface 760. Injecting high-temperature, high-pressure gas into the fifth pipe 410 can adjust the pressure applied to the first interface 750; similarly, injecting high-temperature, high-pressure gas into the seventh pipe 430 can adjust the pressure applied to the second interface 760. Two pressure sensors are installed to monitor the pressure applied to the first interface 750 and the second interface 760. Based on the actual conditions of high-temperature and high-pressure gas wells, the effects of different temperatures and pressures on the cementing strength of the cementing surface are simulated, thereby measuring the cementing strength of the cementing surface under high-temperature conditions.

[0080] Pressure gauges are installed on all pipelines.

[0081] In this embodiment, pressure gauges are installed on the first pipe 210, the second pipe 220, the third pipe 310, the fourth pipe 320, the fifth pipe 410, the sixth pipe 420, the seventh pipe 430, and the eighth pipe 440. Each pressure gauge is used to measure the pressure value on the corresponding pipe.

[0082] The second test system 500 includes a first pressure sensor 510 and a second pressure sensor 520.

[0083] In this embodiment, the first pressure sensor 510 is used to monitor the pressure applied to the first interface 750 of the cementing surface, and the second pressure sensor 520 is used to monitor the pressure applied to the second interface 760 of the cementing surface.

[0084] Specifically, the second testing system 500 is used to measure the mechanical bonding strength of the cementing surface, including a first pressure sensor 510 and a second pressure sensor 520. The first pressure sensor 510 monitors the pressure applied to the first interface 750 of the cementing surface, and the second pressure sensor 520 monitors the pressure applied to the second interface 760 of the cementing surface.

[0085] Optionally, in this embodiment, the mechanical bonding strength of the cementing surface is measured by the second testing system 500, the universal pressure testing machine 910, the hydraulic press 920, the upper cement sheath pressure sensor 930, the lower cement sheath force transmission component 940, the upper cement sheath force transmission component 950, and the casing force transmission component 960.

[0086] The first testing system is used to measure the hydraulic bonding strength of the cementing surface, and the second testing system is used to measure the mechanical bonding strength of the cementing surface. By changing different testing systems, the mechanical bonding strength of the cementing surface can be measured under different temperature and pressure conditions while measuring the hydraulic bonding strength of the cementing surface. This provides a basis for measuring the bonding strength of the cementing surface and solves the problem that existing cementing surface performance testing equipment cannot meet the requirements for measuring mechanical bonding strength under high temperature and high pressure conditions.

[0087] Optionally, in this embodiment, the first testing system 400 is connected to the first upper vessel cover 970, and the second testing system 500 is connected to the second upper vessel cover 980. When measuring the cement sheath interface bonding strength, an upper sealing ring 990 and a lower sealing ring 991 are also provided, both used to seal the first interface and the second interface of the cementing bonding surface to prevent gas intrusion.

[0088] The acoustic variable density logging system 600 includes an ultrasonic component 610 and an acoustic variable density logging instrument 620, which are used together to detect the amplitude of the first wave of the casing 720 and to determine the cementing condition of the cementing surface based on the amplitude.

[0089] In this embodiment, the ultrasonic component 610 is turned on, and the acoustic variable density logging tool 620 is used to measure the amplitude of the first wave inside the casing 720 in real time, and the cementing condition of the cementing surface is judged based on the amplitude.

[0090] This application provides a device for measuring the bonding strength of the cement sheath interface in high-temperature, high-pressure wells and thermal recovery wells, comprising: a hydrothermal reactor, a casing pressure control system, a confining pressure control system, a first testing system, a second testing system, and an acoustic variable density logging system; the hydrothermal reactor includes a reactor body, a formation model is disposed within the reactor body, and a casing is disposed within the formation model; a confining pressure cavity is formed between the formation model and the reactor body, and an annular structure is formed between the casing and the formation model, the annular structure being used to form a cement sheath, the first interface of the cement bonding surface is the interface between the cement sheath and the casing, and the second interface of the cement bonding surface is the interface between the cement sheath and the formation model; the casing pressure control system includes a first pipe and a second pipe, the first pipe being connected to a heater; the confining pressure control system includes a third pipe and a fourth pipe; the first testing system includes a fifth pipe, a sixth pipe, a seventh pipe, and an eighth pipe; pressure gauges are installed on each pipe; the second testing system includes a first pressure sensor and a second pressure sensor; the acoustic variable density logging system includes an ultrasonic component and an acoustic variable density logging instrument, which are used together to detect the amplitude of the first wave of the casing wave inside the casing and to determine the bonding condition of the cement bonding surface based on the amplitude. Through the above structural design, the following technical effects are achieved: The first pipeline is connected to the heater. The temperature of the high-temperature gas injected into the first pipeline is adjusted using an electric heater. The temperature on the first pipeline is observed. Considering the actual temperature variation range of the wellbore in thermal recovery wells, the casing temperature is increased from the initial formation temperature to the corresponding wellbore temperature when hot steam is injected. Considering the actual well-closing time, the final wellbore temperature after closing, and the number of cycles, the system temperature reduction gradient, final temperature, and number of cycles are set to simulate the steam injection process of thermal recovery wells. This allows for the measurement of the cementing strength of the cemented surface in thermal recovery wells under multiple cycle temperature conditions, overcoming the limitation of existing equipment for measuring the cementing strength of thermal recovery wells, which cannot continuously measure mechanical or hydraulic cementing. The challenge of cement bond strength is addressed by simulating the effects of different temperatures and pressures on the cement bond strength of cemented surfaces under high-temperature and high-pressure conditions, based on the actual conditions of high-temperature and high-pressure gas wells. The first testing system measures the hydraulic cement bond strength, while the second system measures the mechanical cement bond strength. By changing the testing systems, the mechanical cement bond strength can be measured under different temperature and pressure conditions, providing a basis for measuring the cement bond strength and solving the problem that existing cement bond performance testing equipment cannot meet the requirements for measuring mechanical cement bond strength under high-temperature and high-pressure conditions.

[0091] In one possible design, based on the above embodiments, this application provides a device for measuring the bonding strength of the cement sheath interface between high-temperature and high-pressure wells and thermal recovery wells.

[0092] The formation model 710 is cylindrical in shape; a wellbore is located at the center of the formation model 710, and the casing 720 is installed inside the wellbore.

[0093] In this embodiment, the formation model 710 has a cylindrical structure with a wellbore centrally located inside, and a casing 720 is installed inside the wellbore.

[0094] An ultrasonic component 610 is installed at the center of the casing 720, and the ultrasonic component 610 is connected to the acoustic variable density logging tool 620.

[0095] In this embodiment, the ultrasonic component 610 and the acoustic variable density logging tool 620 are used to measure the attenuation value and amplitude of the casing wave in the circumferential direction of the wellbore. The usage method and effect of the ultrasonic component 610 and the acoustic variable density logging tool 620 in this embodiment are similar to those in the above embodiments, and will not be repeated here.

[0096] Based on the above embodiments, this application provides a device for measuring the bonding strength of the cement sheath interface between high-temperature and high-pressure wells and thermal recovery wells.

[0097] The first pipeline 210 is also equipped with a first constant speed and constant pressure pump 2101 and a first control valve 2102, and the second pipeline 220 is also equipped with a second control valve 2201; the first pipeline 210 is connected to the pressure storage tank 810 through a heater 770, and the second pipeline 220 is connected to the pressure storage tank 810.

[0098] In this embodiment, the first constant-speed and constant-pressure pump 2101 and the first control valve 2102 are a constant-speed and constant-pressure pump and a control valve installed on the first pipeline 210, and the second control valve 2201 is a control valve installed on the second pipeline 220. The first constant-speed and constant-pressure pump 2101 is used to maintain the stability of the gas flow rate and pressure in the first pipeline 210. The advantage of this arrangement is that the system flow rate and pressure are stabilized through automatic adjustment of the pump, unaffected by changes in external system demand. The first control valve 2102 is used to control the flow rate of the gas in the first pipeline 210, and the second control valve 2201 is used to control the flow rate of the gas in the second pipeline 220. The advantage of this arrangement is that the gas flow rate can be precisely controlled through the control valves, ensuring that the gas flow rate in the pipeline meets the system design requirements. The pressure storage tank 810 is used to discharge high-temperature gas. The function and effect of the second control valve 2201 are similar to those of the first control valve 2102, and will not be described again here.

[0099] Based on the above embodiments, this application provides a device for measuring the bonding strength of the cement sheath interface between high-temperature and high-pressure wells and thermal recovery wells.

[0100] The third pipe 310 is also equipped with a second constant speed and constant pressure pump 3101 and a third control valve 3102, and the fourth pipe 320 is also equipped with a fourth control valve 3201; the third pipe 310 is connected to the injection tank 820, and the fourth pipe 320 is connected to the waste liquid tank 830.

[0101] In this embodiment, the second constant-speed and constant-pressure pump 3101 and the third control valve 3102 are a constant-speed and constant-pressure pump and a control valve installed on the third pipeline 310, and the fourth control valve 3201 is a control valve installed on the fourth pipeline 320. The second constant-speed and constant-pressure pump 3101 is used to maintain the stability of the flow rate and pressure of the liquid flowing into the third pipeline 310, the third control valve 3102 is used to control the flow rate of the liquid flowing into the third pipeline 310, the fourth control valve 3201 is used to control the flow rate of the liquid in the fourth pipeline 320, the injection tank 820 is used to discharge the high-temperature liquid, and the waste liquid tank 830 is used to collect the high-temperature liquid. The effects of the constant-speed and constant-pressure pump and control valve in this embodiment are similar to those in the above embodiments, and will not be described again here.

[0102] Based on the above embodiments, this application provides a device for measuring the bonding strength of the cement sheath interface between high-temperature and high-pressure wells and thermal recovery wells.

[0103] The fifth pipeline 410 is also equipped with a third constant speed and constant pressure pump 4101 and a fifth control valve 4102, and the sixth pipeline 420 is also equipped with a sixth control valve 4201; the fifth pipeline 410 is connected to the first gas injection tank 840, and the sixth pipeline 420 is connected to the first waste gas tank 850.

[0104] In this embodiment, the third constant-speed and constant-pressure pump 4101 and the fifth control valve 4102 are a constant-speed and constant-pressure pump and control valve installed on the fifth pipeline 410, and the sixth control valve 4201 is a control valve installed on the sixth pipeline 420. The third constant-speed and constant-pressure pump 4101 is used to maintain the stability of the gas flow rate and pressure in the fifth pipeline 410, the fifth control valve 4102 is used to control the gas flow rate in the fifth pipeline 410, the sixth control valve 4201 is used to control the gas flow rate in the sixth pipeline 420, the first gas injection tank 840 is used to discharge high-temperature gas, and the first waste gas tank 850 is used to collect high-temperature gas. The effects of the constant-speed and constant-pressure pump and control valve in this embodiment are similar to those in the above embodiments, and will not be described again here.

[0105] Based on the above embodiments, this application provides a device for measuring the bonding strength of the cement sheath interface between high-temperature and high-pressure wells and thermal recovery wells.

[0106] The seventh pipe 430 is also equipped with a fourth constant speed and constant pressure pump 4301 and a seventh control valve 4302, and the eighth pipe 440 is also equipped with an eighth control valve 4401; the seventh pipe 430 is connected to the second gas injection tank 860, and the eighth pipe 440 is connected to the second waste gas tank 870.

[0107] In this embodiment, the fourth constant-speed and constant-pressure pump 4301 and the seventh control valve 4302 are a constant-speed and constant-pressure pump and control valve installed on the seventh pipeline 430, and the eighth control valve 4401 is a control valve installed on the eighth pipeline 440. The fourth constant-speed and constant-pressure pump 4301 is used to maintain the stability of the gas flow rate and pressure in the seventh pipeline 430, the seventh control valve 4302 is used to control the gas flow rate in the seventh pipeline 430, the eighth control valve 4401 is used to control the gas flow rate in the eighth pipeline 440, the second gas injection tank 860 is used to discharge high-temperature gas, and the second waste gas tank 870 is used to collect high-temperature gas. The effects of the constant-speed and constant-pressure pump and control valve in this embodiment are similar to those in the above embodiments, and will not be described again here.

[0108] Based on the above embodiments, this application provides a device for measuring the bonding strength of the cement sheath interface between high-temperature and high-pressure wells and thermal recovery wells.

[0109] One end of each of the first pipe 210 and the second pipe 220 passes through the vessel body 110 and is placed inside the pressure chamber 880. The other end of each of the first pipe 210 and the second pipe 220 is connected to the pressure storage tank 810.

[0110] In this embodiment, the lower end of the vessel body 110 is provided with a casing pressure outlet, a confining pressure outlet, a first interface outlet for cementing bonding, a second interface outlet for cementing bonding, and a lower sealing ring. The casing pressure outlet is connected to the casing pressure cavity 880, the confining pressure outlet is connected to the confining pressure cavity 730, the first interface outlet for cementing bonding is connected to the first interface 750 of the cementing bonding, and the second interface outlet for cementing bonding is connected to the second interface 760 of the cementing bonding. The lower sealing ring is used to seal the first interface and the second interface of the cementing bonding to prevent gas intrusion.

[0111] One end of the first pipe 210 passes through the pressure injection port and extends into the vessel body 110, and is placed inside the pressure chamber 880. The other end of the first pipe 210 is connected to the pressure storage tank 810. One end of the second pipe 220 passes through the pressure outlet and extends into the vessel body 110, and is placed inside the pressure chamber 880. The other end of the second pipe 220 is connected to the pressure storage tank 810.

[0112] One end of each of the third pipe 310 and the fourth pipe 320 passes through the vessel body 110 and is placed in the confining pressure chamber 730. The other end of the third pipe 310 is connected to the injection tank 820, and the other end of the fourth pipe 320 is connected to the waste liquid tank 830.

[0113] In this embodiment, one end of the third pipe 310 extends into the vessel body 110 through the confining pressure injection port and is placed inside the confining pressure cavity 730, while the other end of the third pipe 310 is connected to the injection tank 820; one end of the fourth pipe 320 extends into the vessel body 110 through the confining pressure outlet and is placed inside the confining pressure cavity 730, while the other end of the fourth pipe 320 is connected to the waste liquid tank 830.

[0114] One end of each of the fifth pipe 410 and the sixth pipe 420 passes through the vessel body 110 and is placed inside the annular structure. The other end of the fifth pipe 410 is connected to the first gas injection tank 840, and the other end of the sixth pipe 420 is connected to the first waste gas tank 850.

[0115] In this embodiment, one end of the fifth pipe 410 passes through the injection port of the first interface of the cementing surface and extends into the vessel body 110, and is placed inside the annular structure. The other end of the fifth pipe 410 is connected to the first gas injection tank 840. One end of the sixth pipe 420 passes through the outlet of the first interface of the cementing surface and extends into the vessel body 110, and is placed inside the annular structure. The other end of the sixth pipe 420 is connected to the first waste gas tank 850.

[0116] One end of the seventh pipe 430 and the eighth pipe 440 are both placed inside the annular structure through the vessel body 110. The other end of the seventh pipe 430 is connected to the second gas injection tank 860, and the other end of the eighth pipe 440 is connected to the second waste gas tank 870.

[0117] In this embodiment, one end of the seventh pipe 430 passes through the injection port of the second interface of the cementing surface and extends into the vessel body 110, and is placed inside the annular structure. The other end of the seventh pipe 430 is connected to the second gas injection tank 860. One end of the eighth pipe 440 passes through the outlet of the second interface of the cementing surface and extends into the vessel body 110, and is placed inside the annular structure. The other end of the eighth pipe 440 is connected to the second waste gas tank 870.

[0118] This embodiment provides a method for measuring the bonding strength of the cement sheath interface in high-temperature, high-pressure wells and thermal recovery wells. The method uses the bonding strength measuring device for the cement sheath interface in high-temperature, high-pressure wells and thermal recovery wells provided in the above embodiment. The device includes a hydrothermal reactor and a casing pressure control system. The hydrothermal reactor includes a reactor body, a formation model is installed inside the reactor body, and a casing is installed inside the formation model. The casing pressure control system includes a first pipe connected to a heater, forming an annular structure between the casing and the formation model. The annular structure is used to form a cement sheath. The first interface of the cementing bonding surface is the interface between the cement sheath and the casing, and the second interface of the cementing bonding surface is the interface between the cement sheath and the formation model. The method includes:

[0119] S101. Adjust the temperature conditions of the first pipeline by using a heater, and test the hydraulic bonding strength of the first interface of the cementing surface, the hydraulic bonding strength of the second interface of the cementing surface, the mechanical bonding strength of the first interface of the cementing surface, and the mechanical bonding strength of the second interface of the cementing surface under different temperature conditions.

[0120] In this embodiment, the temperature conditions include high temperature conditions and cyclic temperature conditions. High temperature conditions are conditions that are higher than the preset temperature.

[0121] Based on the above embodiments, this application provides a method for measuring the bonding strength of the cement sheath interface in high-temperature and high-pressure wells and thermal recovery wells. The cement sheath interface bonding strength measuring device further includes a second testing system. The first testing system in the device further includes a fifth pipe, a sixth pipe, a seventh pipe, an eighth pipe, and a pressure gauge installed on each pipe. The second testing system includes a first pressure sensor and a second pressure sensor.

[0122] Cement grout is injected into the annular structure to obtain a cement ring; when the preset temperature value is determined based on high temperature conditions, the curing temperature of the cement ring is set as the preset temperature value; when the preset temperature value is determined based on the circulating temperature conditions, the gas temperature in the first pipeline is adjusted to the preset temperature value by the heater.

[0123] In this embodiment, the cement slurry used in the experiment is prepared, and then the prepared cement slurry is injected into the annular structure to form a cement ring.

[0124] After determining the preset temperature value based on the high-temperature conditions, and on the basis of conducting normal temperature tests, the cement bonding strength of the cementing surface of high-temperature wells at different temperatures is further measured. At this time, the curing temperature of the cement sheath needs to be set to the preset temperature value, that is, the curing temperature of the cement sheath needs to be set to the temperature of the required high-temperature well. S101 specifically includes the following steps:

[0125] S201. Record the initial reading of the pressure gauge on the fifth pipe. Apply pressure to the fifth pipe. When the reading of the pressure gauge on the sixth pipe begins to increase, stop applying pressure to the fifth pipe. When the reading of the pressure gauge on the sixth pipe is equal to the reading of the pressure gauge on the fifth pipe, obtain the hydraulic bonding strength of the first interface of the cementing surface under the preset temperature based on the difference between the readings of the pressure gauges on the sixth and fifth pipes when the pressure increase value changed last time.

[0126] In this embodiment, S201 includes the following steps:

[0127] S2011. Open the fifth and sixth control valves, adjust the third constant speed and pressure pump, and inject gas into the injection port of the first interface of the cementing surface through the fifth pipeline. Record the initial reading P1 of the pressure gauge on the fifth pipeline. Combined with the reading of the pressure gauge on the fifth pipeline, increase the gas pressure in the fifth pipeline in increments of 0.5 MPa. After each increase in gas pressure, let it stand for more than 10 minutes. Observe the readings of the pressure gauges on the fifth and sixth pipelines in real time to obtain the pressure change at the outlet of the first interface of the cementing surface. When the reading of the pressure gauge on the sixth pipeline remains unchanged, it indicates that the first interface of the cementing surface can withstand the pressure difference between the inlet and outlet ends.

[0128] S2012. Continue to introduce gas through the fifth pipeline, pressurizing the injection port of the first interface of the cementing surface at a pressurization value of 0.5 MPa each time, so that the pressure difference between the injection port and the outlet of the first interface of the cementing surface gradually increases. Observe the reading of the pressure gauge on the sixth pipeline in real time. When the reading of the pressure gauge on the sixth pipeline begins to increase, stop pressurizing the first interface of the cementing surface and let it stand for 10 minutes for observation.

[0129] S2013. As the pressure difference between the injection port and the outlet of the first interface of the cementing surface continues to increase, when the pressure gauge value on the sixth pipeline suddenly increases to the pressure gauge value on the fifth pipeline, it indicates that the first interface of the cementing surface has debonded. Record the pressure gauge values ​​Pi1 on the fifth pipeline and Po1 on the sixth pipeline when the pressure increase value changes last time. Calculate the difference between Po1 and Pi1 to obtain the maximum sealing pressure difference that the first interface of the cementing surface can withstand when it debonds, that is, to obtain the hydraulic bonding strength of the first interface of the cementing surface under high temperature conditions. At the same time, observe the debonding phenomenon between the casing and the cement sheath using the logging results obtained by the sonic variable density logging tool.

[0130] S202. Record the initial reading of the pressure gauge on the seventh pipe. Apply pressure to the seventh pipe. When the reading of the pressure gauge on the eighth pipe begins to increase, stop applying pressure to the seventh pipe. When the reading of the pressure gauge on the eighth pipe is equal to the reading of the pressure gauge on the seventh pipe, obtain the hydraulic bonding strength of the second interface of the cementing surface under the preset temperature based on the difference between the readings of the pressure gauges on the eighth and seventh pipes when the pressure value changed last time.

[0131] In this embodiment, S202 includes the following steps:

[0132] S2021. Open the seventh and eighth control valves, adjust the fourth constant speed and pressure pump, and inject gas into the injection port of the second interface of the cementing surface through the seventh pipeline. Record the initial reading P2 of the pressure gauge on the seventh pipeline. Combined with the reading of the pressure gauge on the seventh pipeline, increase the gas pressure in the seventh pipeline in increments of 0.5 MPa. After each increase in gas pressure, let it stand for more than 10 minutes. Observe the readings of the pressure gauges on the seventh and eighth pipelines in real time to obtain the pressure change at the outlet of the second interface of the cementing surface. When the reading of the pressure gauge on the eighth pipeline remains unchanged, it indicates that the second interface of the cementing surface can withstand the pressure difference between the inlet and outlet ends.

[0133] S2022. Continue to introduce gas through the seventh pipe, pressurizing the injection port of the second interface of the cementing surface at a pressurization value of 0.5 MPa each time, so that the pressure difference between the injection port and the outlet of the second interface of the cementing surface gradually increases. Observe the reading of the pressure gauge on the eighth pipe in real time. When the reading of the pressure gauge on the eighth pipe begins to increase, stop pressurizing the second interface of the cementing surface and let it stand for 10 minutes for observation.

[0134] S2023. As the pressure difference between the injection port and the outlet of the second interface of the cementing surface continues to increase, when the reading of the pressure gauge on the eighth pipe suddenly increases to the reading of the pressure gauge on the seventh pipe, it indicates that the second interface of the cementing surface has debonded. Record the readings Pi2 of the pressure gauge on the seventh pipe and Po2 of the pressure gauge on the eighth pipe when the pressure increase value changes last time. Calculate the difference between Po2 and Pi2 to obtain the maximum sealing pressure difference that the second interface of the cementing surface can withstand when it debonds, that is, to obtain the hydraulic bonding strength of the second interface of the cementing surface under high temperature conditions. At the same time, the logging results obtained by the sonic variable density logging tool are used to simultaneously observe the debonding phenomenon between the formation model and the cement sheath.

[0135] S203. Apply pressure to the casing and observe the value of the first pressure sensor in real time. When the cement sheath separates from the casing, obtain the mechanical bonding strength of the first interface of the cementing surface under the preset temperature based on the value of the first pressure sensor when the pressure value changes last time.

[0136] In this embodiment, S203 includes the following steps:

[0137] S2031. Turn on the universal pressure testing machine and adjust the pressure applied to the lower part of the cement sheath through the force transmission component installed at the bottom of the cement sheath, i.e., the lower cement sheath force transmission component. Turn on the hydraulic press and apply the same pressure as the force transmission component installed at the bottom of the cement sheath through the force transmission component installed at the top of the cement sheath, i.e., the upper cement sheath force transmission component, to prevent the cement sheath from slipping when measuring the mechanical bonding strength of the first interface of the cementing bonding surface.

[0138] S2032. A force transmission component, namely the casing force transmission component, is installed at the lower part of the casing. A first pressure sensor is installed on the force transmission component. The pressure applied to the casing is gradually increased by a loading amplitude of 0.5 MPa based on the reading of the first pressure sensor. The reading of the first pressure sensor is observed in real time to obtain the pressure change of the first interface of the cementing surface.

[0139] S2033. As the pressure on the first interface of the cementing surface continues to increase, when the casing leaves the top of the cement sheath to the upper end, it indicates that the casing and cement sheath have separated. Record the pressure applied when the pressure value changed last time to obtain the mechanical bonding strength of the first interface of the cementing surface, that is, to obtain the mechanical bonding strength of the first interface of the cementing surface under high temperature conditions. At the same time, the logging results obtained by using the sonic variable density logging tool are used to simultaneously observe the separation phenomenon between the casing and the cement sheath.

[0140] Each system in this embodiment is connected to a computer.

[0141] S204. Apply pressure to the cement sheath and observe the value of the second pressure sensor in real time. When the cement sheath separates from the formation model, obtain the mechanical bonding strength of the second interface of the cementing surface under the preset temperature based on the value of the second pressure sensor when the pressure value changes last time.

[0142] In this embodiment, S204 includes the following steps:

[0143] S2041. Turn off the hydraulic press and release the pressure applied to the upper end of the cement ring.

[0144] S2042. Restart the universal pressure testing machine. Through the force transmission component installed at the bottom of the cement sheath, combined with the reading of the second pressure sensor installed on the force transmission component, gradually increase the pressure applied to the cement sheath in increments of 0.5 MPa. Observe the reading of the second pressure sensor in real time to obtain the pressure change of the second interface of the cementing bonding surface.

[0145] S2043. As the pressure on the second interface of the cementing surface continues to increase, when the cement sheath leaves the top of the formation model and reaches the upper end, it indicates that the cement sheath and the formation model have separated. Record the pressure applied when the pressure value changed last time to obtain the mechanical bonding strength of the second interface of the cementing surface, that is, to obtain the mechanical bonding strength of the second interface of the cementing surface under high temperature conditions. At the same time, the logging results obtained by the sonic variable density logging tool are used to simultaneously observe the separation phenomenon between the cement sheath and the formation model.

[0146] After determining the preset temperature value based on the circulating temperature conditions, the cement bonding strength of the cement sheath in the thermal recovery well is measured under multiple circulating temperature conditions. After simulating the curing process of the cement sheath and determining its solidification state, if the strength of the cement sheath no longer changes, the temperature of the high-temperature gas flowing out of the casing pressure storage tank is adjusted using an electric heater. The readings of the temperature sensor on the first pipeline are observed. Considering the actual temperature variation range of the thermal recovery wellbore, the casing temperature is increased from the initial formation temperature to the temperature corresponding to the wellbore when injecting hot steam. Considering the actual well-closing time, the final wellbore temperature after closing, and the number of cycles, the system temperature reduction gradient, final temperature, and number of cycles are set. Simultaneously, a sonic variable density logging tool is used for measurement, and the strength change of the cement sheath is observed synchronously under different temperature changes and number of cycles. Then, S101 includes S201, S202, S203, and S204. Specifically, S201 includes S2011, S2012, and S2013, through which the hydraulic bonding strength of the first interface of the cementing surface under the set circulating temperature condition is finally obtained; S202 includes S2021, S2022, and S2023, through which the hydraulic bonding strength of the second interface of the cementing surface under the set circulating temperature condition is finally obtained; S203 includes S2031, S2032, and S2033, through which the mechanical bonding strength of the first interface of the cementing surface under the set circulating temperature condition is finally obtained; and S204 includes S2041, S2042, and S2043, through which the mechanical bonding strength of the second interface of the cementing surface under the set circulating temperature condition is finally obtained. The contents of S201, S202, S203, S204, S2011, S2012, S2013, S2021, S2022, S2023, S2031, S2032, S2033, S2041, S2042, and S2043 have been described in detail above and will not be repeated here.

[0147] This embodiment provides a method for measuring the bonding strength of the cement sheath interface between high-temperature and high-pressure wells and thermally recovered wells. This method can achieve the same effect as the method provided in the above embodiment, and will not be described again here.

[0148] Based on the above embodiments, this application provides a method for measuring the bonding strength of the cement sheath interface between a high-temperature, high-pressure well and a thermally recovered well. The measuring device for the bonding strength of the cement sheath interface between a high-temperature, high-pressure well and a thermally recovered well further includes a first upper cover and a second upper cover. The second upper cover includes a recessed structure. The first upper cover is provided with a first injection port, a second injection port, a third injection port, and a fourth injection port. The second upper cover is provided with a fifth injection port and a sixth injection port.

[0149] Before proceeding with S201, the following is also included:

[0150] Install the first upper vessel cover, and connect the first, third, fifth, and seventh pipes to the first upper vessel cover through the first, second, third, and fourth injection ports, respectively.

[0151] The first upper cover is also equipped with an upper sealing ring, which is used to seal the first interface of the cementing surface and the second interface of the cementing surface to prevent gas intrusion.

[0152] After S202 is executed, but before S203 is executed, the following is also included:

[0153] Replace the first upper vessel cover with the second upper vessel cover, and connect the first pipe and the third pipe to the second upper vessel cover through the first injection port and the second injection port, respectively.

[0154] In this embodiment, the first injection port is a casing pressure injection port, the second injection port is a confining pressure injection port, the third injection port is a first interface injection port for the cementing bonding surface, and the fourth injection port is a second interface injection port for the cementing bonding surface. The top of the vessel body is fixedly connected to the first or second upper vessel cover by bolts. The first upper vessel cover is used when measuring hydraulic bonding strength, and the second upper vessel cover is used when measuring mechanical bonding strength. By changing different upper vessel covers, the mechanical bonding strength can be measured without removing the cement sheath when measuring the hydraulic bonding strength of the cementing bonding surface under different temperature and pressure conditions. This solves the problem that existing cementing bonding surface performance testing equipment cannot meet the requirements for measuring mechanical bonding strength under high temperature and high pressure conditions.

[0155] The following are specific methods for measuring the bonding strength of cementing surfaces in wells at room temperature:

[0156] S301. Prepare a formation model. The formation model has a cylindrical structure with a wellbore located in the center inside.

[0157] S302. The formation model is wrapped in a high-temperature resistant rubber sleeve and placed in the body of the hydrothermal reactor. The casing is then placed in the wellbore of the formation model in the center. Finally, the ultrasonic component is placed in the casing in the center.

[0158] S303, Prepare cement slurry for the experiment.

[0159] S304. The prepared cement slurry is injected into the annular structure to form a cement ring. The first interface of the cementing bonding surface is the interface between the cement ring and the casing, and the second interface of the cementing bonding surface is the interface between the cement ring and the formation model. The top of the hydrothermal reactor body is sealed with the first upper reactor cover. The casing pressure control system, the confining pressure control system, the first testing system, and the acoustic variable density logging system are installed in sequence.

[0160] S305, pressure tests were conducted on the sleeve pressure chamber, confining pressure chamber, and annular structure to ensure that the hydrothermal reactor has good sealing performance.

[0161] S306. After the pressure test is completed, the casing pressure control system is activated, and high-pressure gas is pumped into the casing pressure chamber to simulate the internal pressure of the casing and the ground temperature. Containing pressure is applied to the confining pressure chamber, and annular pressure is applied to the annular structure to simulate the curing process of the cement annulus. The specific steps include:

[0162] S3061. Open the third and fourth control valves, adjust the second constant speed and constant pressure pump, and inject high-pressure liquid into the confining pressure chamber through the third pipeline to simulate the in-situ stress on the formation model. Observe the reading of the pressure gauge on the third pipeline in real time. When the reading of the pressure gauge on the third pipeline reaches the preset confining pressure value, close the third control valve, the fourth control valve, and the second constant speed and constant pressure pump to stop injecting high-pressure liquid into the confining pressure chamber and maintain the confining pressure value of the formation model.

[0163] S3062. Open the first control valve and the second control valve, adjust the first constant speed and constant pressure pump, and inject high temperature and high pressure gas into the casing pressure chamber through the first pipeline to simulate the casing internal pressure and normal well temperature. Observe the reading of the pressure gauge on the first pipeline and the reading of the temperature sensor installed on the first pipeline in real time. When the reading of the pressure gauge on the first pipeline reaches the preset casing internal pressure value and the reading of the temperature sensor installed on the first pipeline reaches the preset normal temperature value, continuously circulate the high pressure gas under the current temperature and pressure conditions to maintain the pressure and temperature values ​​of the casing.

[0164] S3063. Open the fifth and sixth control valves, adjust the third constant speed and constant pressure pump, and inject high-pressure gas into the annular structure through the fifth pipeline to simulate the internal pressure of the annular structure. Observe the reading of the pressure gauge on the sixth pipeline in real time. When the reading of the pressure gauge on the sixth pipeline reaches the preset annular pressure value, close the fifth and sixth control valves, stop injecting high-pressure liquid into the annular structure, and maintain the annular pressure value to hold the pressure.

[0165] S307. Wait for more than 48 hours until the cement slurry solidifies, then turn on the ultrasonic component and use the acoustic variable density logging tool to measure the attenuation of the casing wave in real time. Based on the attenuation of the casing wave, determine the strength change of the cement sheath and the solidification state of the cement sheath. After the strength of the cement sheath no longer changes, start the cement sheath sealing performance test experiment.

[0166] S308, execute S2011, S2012 and S2013. S2013 yields the hydraulic bonding strength of the first interface of the cementing surface under normal temperature conditions. After executing S2013, execute S2021, S2022 and S2023. S2023 yields the hydraulic bonding strength of the second interface of the cementing surface under normal temperature conditions.

[0167] S309. Without installing the first test system, replace the second upper vessel cover and install the second test system. Repeat S301-S307 to re-simulate the same temperature and pressure environment as when measuring the hydraulic bonding strength at room temperature.

[0168] S310, execute S2031, S2032 and S2033, and obtain the mechanical bonding strength of the first interface of the cementing surface under normal temperature conditions through S2033; execute S2041, S2042 and S2043, and obtain the mechanical bonding strength of the second interface of the cementing surface under normal temperature conditions through S2043.

[0169] The following are specific methods for measuring the cement bond strength of cemented surfaces in high-temperature wells under different temperature conditions:

[0170] S401, execute S301-S307, but in S306, the curing temperature of the cement ring must be set to the temperature of the required high-temperature well.

[0171] S402, execute S2011, S2012 and S2013. S2013 yields the hydraulic bonding strength of the first interface of the cementing surface under high temperature conditions. After executing S2013, execute S2021, S2022 and S2023. S2023 yields the hydraulic bonding strength of the second interface of the cementing surface under high temperature conditions.

[0172] S403. Without installing the first test system, replace the second upper vessel cover and install the second test system. Repeat S301-S307 to re-simulate the temperature and pressure environment of the required high-temperature well.

[0173] S404, execute S2031, S2032 and S2033, and obtain the mechanical bonding strength of the first interface of the cementing surface under high temperature conditions through S2033; execute S2041, S2042 and S2043, and obtain the mechanical bonding strength of the second interface of the cementing surface under high temperature conditions through S2043.

[0174] The following is a specific method for measuring the cement bond strength of cemented surfaces in thermal recovery wells under set circulation temperature conditions:

[0175] S501 executes S301-S307, but S3062 simulates the internal pressure of the thermal recovery well casing and the actual initial formation temperature of the thermal recovery well.

[0176] S502. After the strength of the cement sheath no longer changes, use an electric heater to adjust the temperature of the high-temperature gas flowing out of the casing pressure storage tank, observe the reading of the temperature sensor installed on the first pipeline, consider the actual temperature variation range of the wellbore in the thermal recovery well, and raise the casing temperature from the initial formation temperature to the temperature corresponding to the wellbore when injecting hot steam. Consider the actual well-closing time, the final temperature of the wellbore after closing, and the number of cycles, set the system temperature reduction gradient, the final temperature, and the number of cycles. At the same time, use an acoustic variable density logging tool to measure, and simultaneously observe the strength change of the cement sheath under different temperature changes and number of cycles.

[0177] S503, execute S2011, S2012 and S2013. S2013 yields the hydraulic bonding strength of the first interface of the cementing surface under the set circulation temperature. After executing S2013, execute S2021, S2022 and S2023. S2023 yields the hydraulic bonding strength of the second interface of the cementing surface under the set circulation temperature.

[0178] S504. Without installing the first test system, replace the second upper vessel cover and install the second test system. Repeat S301-S307 to re-simulate and measure the same temperature and pressure environment as when measuring the hydraulic bonding strength under the set circulating temperature conditions.

[0179] S505, execute S2031, S2032 and S2033, and obtain the mechanical bonding strength of the first interface of the cementing surface under the set circulating temperature conditions through S2033; execute S2041, S2042 and S2043, and obtain the mechanical bonding strength of the second interface of the cementing surface under the set circulating temperature conditions through S2043.

[0180] By combining the results of acoustic variable density logging with the measurement, the cementing strength of the cementing surface was accurately measured. At the same time, the change of cementing strength of the cement sheath was observed simultaneously using an acoustic variable density logging tool, overcoming the problem that existing equipment for measuring the cementing strength of thermal recovery wells cannot continuously measure the mechanical or hydraulic cementing strength.

[0181] So far, the technical solutions of the embodiments of this application have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is readily understood by those skilled in the art that the protection scope of the embodiments of this application is obviously not limited to these specific embodiments. The above embodiments are only used to illustrate the technical solutions of the embodiments of this application, and not to limit them. Although the embodiments of this application have been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of this application.

Claims

1. A device for measuring the bonding strength of the cement sheath interface in high-temperature and high-pressure wells and thermal recovery wells, characterized in that, include: The system includes a hydrothermal reactor (100), a casing pressure control system (200), a confining pressure control system (300), a first testing system (400), a second testing system (500), and an acoustic variable density logging system (600). The first testing system (400) is used to measure the hydraulic bonding strength of the cementing surface, and the second testing system (500) is used to measure the mechanical bonding strength of the cementing surface. The hydrothermal reactor (100) includes a reactor body (110); a formation model (710) is provided inside the reactor body (110), and a casing (720) is provided inside the formation model (710); the formation model (710) is cylindrical in shape; a wellbore is provided at the center of the formation model (710), and the casing (720) is provided inside the wellbore; A confining pressure cavity (730) is formed between the formation model (710) and the vessel body (110), and an annular structure is formed between the casing (720) and the formation model (710). The annular structure is used to form a cement sheath (740). The first interface (750) of the cementing bonding surface is the interface between the cement sheath (740) and the casing (720), and the second interface (760) of the cementing bonding surface is the interface between the cement sheath (740) and the formation model (710). The sleeve pressure control system (200) includes a first pipe (210) and a second pipe (220), the first pipe (210) being connected to a heater (770); the first pipe (210) and the second pipe (220) are used together to adjust the pressure applied to the sleeve (720); The confining pressure control system (300) includes a third pipe (310) and a fourth pipe (320); the third pipe (310) and the fourth pipe (320) are used together to adjust the pressure applied to the confining pressure chamber (730); the third pipe (310) is also equipped with a second constant speed and constant pressure pump (3101) and a third control valve (3102), and the fourth pipe (320) is also equipped with a fourth control valve (3201); the third pipe (310) is connected to the injection tank (820), and the fourth pipe (320) is connected to the waste liquid tank (830); The first testing system (400) includes a fifth pipe (410), a sixth pipe (420), a seventh pipe (430), and an eighth pipe (440); the fifth pipe (410) and the sixth pipe (420) are used together to adjust the pressure applied to the first interface (750) of the cementing surface, and the seventh pipe (430) and the eighth pipe (440) are used together to adjust the pressure applied to the second interface (760) of the cementing surface. Each of the aforementioned pipes is equipped with a pressure gauge; The second testing system (500) includes a first pressure sensor (510) and a second pressure sensor (520); the first pressure sensor (510) is used to monitor the pressure applied to the first interface (750) of the cementing surface, and the second pressure sensor (520) is used to monitor the pressure applied to the second interface (760) of the cementing surface. The acoustic variable density logging system (600) includes an ultrasonic component (610) and an acoustic variable density logging tool (620). The ultrasonic component (610) is located at the center of the casing (720) and connected to the acoustic variable density logging tool (620). The ultrasonic component (610) and the acoustic variable density logging tool (620) are used together to measure the attenuation value and amplitude of the casing wave in the circumferential direction of the wellbore, and to determine the cementing condition of the cementing surface based on the amplitude. The device further includes a first upper lid and a second upper lid, the first test system (400) is connected to the first upper lid (970), and the second test system (500) is connected to the second upper lid (980); the first upper lid (970) is provided with a first injection port, a second injection port, a third injection port and a fourth injection port, and the second upper lid (980) includes a recessed structure and is provided with two injection ports; The first upper vessel cover (970) is provided with an upper sealing ring (990), and the lower end of the vessel body (110) is provided with a lower sealing ring (991), a first interface outlet for cementing bonding surface and a second interface outlet for cementing bonding surface; the upper sealing ring (990) and the lower sealing ring (991) are both used to seal the first interface (750) and the second interface (760) of cementing bonding surface. One end of the fifth pipe (410) is connected to the first interface (750) of the cementing surface through the third injection port; one end of the sixth pipe (420) is connected to the first interface (750) of the cementing surface through the outlet of the first interface; one end of the seventh pipe (430) is connected to the second interface (760) of the cementing surface through the fourth injection port; and one end of the eighth pipe (440) is connected to the second interface (760) of the cementing surface through the outlet of the second interface, thereby forming independent air intake and exhaust passages corresponding to the first interface (750) and the second interface (760) of the cementing surface, respectively. When the first upper vessel cover is installed, the first pipe (210), the third pipe (310), the fifth pipe (410), and the seventh pipe (430) are connected to the first upper vessel cover (970) through the first injection port, the second injection port, the third injection port, and the fourth injection port, respectively; when the second upper vessel cover is replaced, the first pipe (210) and the third pipe (310) are connected to the two injection ports of the second upper vessel cover (980), respectively. The second testing system (500) is also used in conjunction with a universal pressure testing machine (910), a hydraulic press (920), an upper cement sheath pressure sensor (930), a lower cement sheath force transmission component (940), an upper cement sheath force transmission component (950), and a casing force transmission component (960) to measure the mechanical bonding strength of the first interface (750) and the second interface (760) of the cementing surface. The first pressure sensor (510) is located at the casing force transmission component (960), and the second pressure sensor (520) is located at the lower cement sheath force transmission component (940).

2. The device for measuring the bonding strength of the cement sheath interface in high-temperature and high-pressure wells and thermal recovery wells according to claim 1, characterized in that, The first pipeline (210) is also equipped with a first constant speed and constant pressure pump (2101) and a first control valve (2102), and the second pipeline (220) is also equipped with a second control valve (2201); the first pipeline (210) is connected to the pressure storage tank (810) through the heater (770), and the second pipeline (220) is connected to the pressure storage tank (810).

3. The device for measuring the bonding strength of the cement sheath interface in high-temperature and high-pressure wells and thermal recovery wells according to claim 2, characterized in that, The fifth pipe (410) is also equipped with a third constant speed and constant pressure pump (4101) and a fifth control valve (4102), and the sixth pipe (420) is also equipped with a sixth control valve (4201); the fifth pipe (410) is connected to the first gas injection tank (840), and the sixth pipe (420) is connected to the first waste gas tank (850).

4. The device for measuring the bonding strength of the cement sheath interface in high-temperature and high-pressure wells and thermal recovery wells according to claim 3, characterized in that, The seventh pipe (430) is also equipped with a fourth constant speed and constant pressure pump (4301) and a seventh control valve (4302), and the eighth pipe (440) is also equipped with an eighth control valve (4401); the seventh pipe (430) is connected to the second gas injection tank (860), and the eighth pipe (440) is connected to the second waste gas tank (870).

5. The device for measuring the bonding strength of the cement sheath interface in high-temperature and high-pressure wells and thermal recovery wells according to claim 4, characterized in that, One end of each of the first pipe (210) and the second pipe (220) passes through the vessel body (110) and is placed in the pressure chamber (880), and the other end of each of the first pipe (210) and the second pipe (220) is connected to the pressure storage tank (810); One end of each of the third pipe (310) and the fourth pipe (320) passes through the vessel body (110) and is placed in the confining pressure cavity (730). The other end of the third pipe (310) is connected to the injection tank (820), and the other end of the fourth pipe (320) is connected to the waste liquid tank (830). One end of each of the fifth pipe (410) and the sixth pipe (420) passes through the vessel body (110) and is placed inside the annular structure. The other end of the fifth pipe (410) is connected to the first gas injection tank (840), and the other end of the sixth pipe (420) is connected to the first waste gas tank (850). One end of each of the seventh pipe (430) and the eighth pipe (440) passes through the vessel body (110) and is placed inside the annular structure. The other end of the seventh pipe (430) is connected to the second gas injection tank (860), and the other end of the eighth pipe (440) is connected to the second waste gas tank (870).

6. The device for measuring the bonding strength of the cement sheath interface in high-temperature and high-pressure wells and thermal recovery wells according to claim 1, characterized in that, The outer wall of the formation model (710) is wrapped with a high-temperature resistant rubber sleeve, and the high-temperature resistant rubber sleeve forms the confining pressure cavity (730) between the inner wall of the vessel body (110).

7. A method for measuring the bonding strength of the cement sheath interface in high-temperature, high-pressure wells and thermal recovery wells, characterized in that, The method is used in the cement sheath interface bonding strength measuring device for high-temperature and high-pressure wells and thermal recovery wells as described in any one of claims 1 to 6. The device comprises: a hydrothermal reactor and a casing pressure control system; wherein the hydrothermal reactor includes a reactor body, a formation model is disposed within the reactor body, and a casing is disposed within the formation model; the casing pressure control system includes a first pipe connected to a heater, and an annular structure is formed between the casing and the formation model, the annular structure being used to form a cement sheath; the first interface of the cementing bonding surface is the interface between the cement sheath and the casing, and the second interface of the cementing bonding surface is the interface between the cement sheath and the formation model, then the method comprises: The temperature conditions of the first pipeline are adjusted by the heater, and the hydraulic bonding strength of the first interface of the cementing surface, the hydraulic bonding strength of the second interface of the cementing surface, the mechanical bonding strength of the first interface of the cementing surface, and the mechanical bonding strength of the second interface of the cementing surface are tested under different temperature conditions; wherein, the temperature conditions include high temperature conditions and circulating temperature conditions, and the high temperature conditions are conditions higher than the preset temperature.

8. The method for measuring the bonding strength of the cement sheath interface in high-temperature and high-pressure wells and thermal recovery wells according to claim 7, characterized in that, The device further includes a second testing system, wherein the first testing system in the device further includes a fifth pipe, a sixth pipe, a seventh pipe, an eighth pipe, and a pressure gauge installed on each of the pipes; wherein the second testing system includes a first pressure sensor and a second pressure sensor; The step of adjusting the temperature conditions of the first pipeline through the heater and testing the hydraulic bonding strength of the first interface, the hydraulic bonding strength of the second interface, the mechanical bonding strength of the first interface, and the mechanical bonding strength of the second interface of the cementing surface under different temperature conditions includes: Record the initial reading of the pressure gauge on the fifth pipeline, apply pressure to the fifth pipeline, and stop applying pressure to the fifth pipeline when the reading of the pressure gauge on the sixth pipeline starts to increase. When the reading of the pressure gauge on the sixth pipeline is equal to the reading of the pressure gauge on the fifth pipeline, obtain the hydraulic bonding strength of the first interface of the cementing surface under the preset temperature based on the difference between the reading of the pressure gauge on the sixth pipeline and the reading of the pressure gauge on the fifth pipeline when the pressure increase value changed last time. When testing the mechanical bonding strength of the first interface of the cementing surface, a universal pressure testing machine is turned on, and pressure is applied to the lower part of the cement sheath through the lower cement sheath force transmission component. At the same time, a hydraulic press is turned on, and the same pressure is applied to the upper part of the cement sheath through the upper cement sheath force transmission component to limit the slippage of the cement sheath. Then, pressure is applied to the casing through the casing force transmission component, and the value of the first pressure sensor is observed in real time. When the cement sheath separates from the casing, the mechanical bonding strength of the first interface of the cementing surface is obtained according to the value of the first pressure sensor when the pressure value changes last time. When testing the mechanical bonding strength of the second interface of the cementing surface, the hydraulic press is turned off and the pressure applied to the upper end of the cement sheath is released. The universal pressure testing machine is restarted, and pressure is applied to the cement sheath through the lower cement sheath force transmission component. The value of the second pressure sensor is observed in real time. When the cement sheath separates from the formation model, the mechanical bonding strength of the second interface of the cementing surface is obtained according to the value of the second pressure sensor when the pressure value changes last time. Record the initial reading of the pressure gauge on the seventh pipe, apply pressure to the seventh pipe, and stop applying pressure to the seventh pipe when the reading of the pressure gauge on the eighth pipe starts to increase. When the reading of the pressure gauge on the eighth pipe is equal to the reading of the pressure gauge on the seventh pipe, obtain the hydraulic bonding strength of the second interface of the cementing surface under the preset temperature based on the difference between the reading of the pressure gauge on the eighth pipe and the reading of the pressure gauge on the seventh pipe when the pressure increase value changed last time. Pressure is applied to the casing, and the value of the first pressure sensor is observed in real time. When the cement sheath separates from the casing, the mechanical bonding strength of the first interface of the cementing surface is obtained under the preset temperature based on the value of the first pressure sensor when the pressure value changes last time. Pressure is applied to the cement sheath, and the value of the second pressure sensor is observed in real time. When the cement sheath separates from the formation model, the mechanical bonding strength of the second interface of the cementing surface is obtained under the preset temperature based on the value of the second pressure sensor when the pressure value changes last time. Specifically, the cement ring is obtained by injecting cement slurry into the annular structure; when the preset temperature value is determined according to the high temperature conditions, the curing temperature of the cement ring is set to the preset temperature value; when the preset temperature value is determined according to the circulating temperature conditions, the gas temperature in the first pipeline is adjusted to the preset temperature value by the heater.

9. The method for measuring the bonding strength of the cement sheath interface in high-temperature and high-pressure wells and thermal recovery wells according to claim 8, characterized in that, The device further includes a first upper vessel cover and a second upper vessel cover. The second upper vessel cover includes a recessed structure. The first upper vessel cover is provided with a first injection port, a second injection port, a third injection port, and a fourth injection port. The second upper vessel cover has two injection ports. Before obtaining the hydraulic bonding strength of the first interface of the cementing surface at the preset temperature, the first upper vessel cover is installed, and the first pipe, the third pipe, the fifth pipe, and the seventh pipe are connected to the first upper vessel cover through the first injection port, the second injection port, the third injection port, and the fourth injection port, respectively. The first upper vessel cover is provided with an upper sealing ring, which is used to seal the first interface of the cementing surface and the second interface of the cementing surface. Before obtaining the mechanical bonding strength of the first interface of the cementing surface at the preset temperature, the first upper vessel cover is replaced with the second upper vessel cover, and the first pipe and the third pipe are respectively connected to the two injection ports of the second upper vessel cover, thereby replacing the first testing system with the second testing system.

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