Method for monitoring physical performance of in-service equipment of nuclear power station based on EMAT

Abstract

The invention discloses a nuclear power station in-service equipment physical performance monitoring method based on EMAT, and belongs to the field of nuclear power station equipment service performance detection. The method comprises the following steps: simultaneously exciting ultrasonic transverse and longitudinal waves by using an EMAT probe; the EMAT sensor is designed to resist high temperature; ultrasonic sound velocity correction in a high-temperature environment; key physical performance parameters such as elastic modulus and Poisson's ratio of in-service equipment in a high-temperature environment are continuously monitored by utilizing sound velocity data of transverse waves and longitudinal waves excited by an EMAT probe. Based on the electromagnetic ultrasonic principle, the method can effectively monitor the elasticity modulus, Poisson's ratio and other key physical performance parameters of the in-service equipment of the nuclear power station at high temperature, corrects the measurement error caused by high temperature, provides an important basis for the health management of the equipment of the nuclear power station, and ensures the feasibility and safety of the equipment.

Description

Technical Field

[0001] The present invention belongs to the technical field of non-destructive testing of nuclear power plants, and more specifically, relates to an electromagnetic ultrasonic method and device for monitoring the physical properties of high-temperature in-service equipment in nuclear power plants. Background Art

[0002] In the inspection of in-service equipment in current nuclear power plants, common non-destructive testing methods include electromagnetic testing, visual inspection, ultrasonic testing, etc. In some special environments, the on-site temperature of nuclear power plants can reach 300 °C and above. For example, the design temperature of the hot section pipe of the primary loop pipeline of a nuclear power plant is 350 °C, and the average temperature during the actual stable operation stage remains at 291 - 310 °C. Therefore, it is necessary to select a suitable inspection method for in-service equipment and design equipment that can meet the requirements of high-temperature applications to effectively complete the monitoring of equipment and meet the monitoring needs in high-temperature environments.

[0003] To ensure the safety performance of in-service equipment in nuclear power plants, non-destructive testing of equipment in high-temperature environments can be achieved through ultrasonic testing. For example, Chinese Patent CN108120768 A discloses an ultrasonic testing method and device for high-temperature elastic modulus, which consists of a heating furnace for placing specimens, a vacuum pump for evacuating the heating furnace, transducers for acoustic wave emission and reception, a water cooler for cooling the transducers, a high-pressure argon gas cylinder for providing inert gas to the heating furnace, and a heating temperature control system to form the entire testing system, and measures the elastic modulus of workpieces using the acoustic wave method. Chinese Patent CN114088815 A discloses a high-temperature material mechanical property elastic modulus and damage holographic testing device, which consists of a left-end hydraulic clamping device, a two-dimensional array phased array ultrasonic testing device, a disk array phased array ultrasonic testing device, an induction heating coil, and a right-end hydraulic clamping device. The disk array phased array detection device is used to transmit and receive longitudinal wave ultrasonic waves for 3D holographic imaging of internal damage defects, and the two-dimensional array phased array detection device is used to transmit and receive transverse wave ultrasonic waves and combine them with the longitudinal wave ultrasonic waves transmitted and received by the disk array phased array detection device to calculate the high-temperature elastic modulus, and the induction heating coil can uniformly heat the specimen.

[0004] The above patents all use ultrasonic testing methods to perform non-destructive testing on workpieces to be tested in high-temperature environments, demonstrating the ability of ultrasonic technology in evaluating the performance of high-temperature materials. However, the above methods are mainly based on piezoelectric ultrasonic methods, usually only capable of short-time detection in high-temperature environments, or requiring the configuration of corresponding water cooling devices. However, in the inspection of in-service equipment in nuclear power plants, online monitoring is particularly important. Therefore, there is an urgent need to design a method that can achieve continuous performance monitoring of high-temperature in-service equipment in nuclear power plants. In contrast, electromagnetic ultrasonic (EMAT) technology can achieve continuous physical property monitoring of high-temperature in-service equipment in nuclear power plants, overcoming the limitation that general ultrasonic sensors can only detect briefly in high-temperature environments. Summary of the Invention

[0005] 1. Problem to be Solved

[0006] The object of the present invention is to provide a method for monitoring the physical properties of in-service equipment in nuclear power plants based on EMAT, so as to effectively and continuously monitor the changes in physical properties in the high-temperature environment of nuclear power plants, and then evaluate the potential failure risks of the equipment.

[0007] 2. Technical Solution

[0008] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0009] The present invention provides a method for monitoring the physical properties of in-service equipment in nuclear power plants based on EMAT, including:

[0010] Designing an EMAT probe to simultaneously excite ultrasonic shear waves and longitudinal waves;

[0011] Designing the EMAT sensor for high-temperature resistance;

[0012] Compensating and correcting the shear wave velocity and longitudinal wave velocity excited by the EMAT probe in a high-temperature environment;

[0013] Using the compensated and corrected shear wave velocity data and longitudinal wave velocity data to continuously monitor key physical property parameters such as elastic modulus and Poisson's ratio of in-service equipment in a high-temperature environment.

[0014] Based on the EMAT detection principle, the present invention designs a high-temperature-resistant EMAT sensor for the special application scenario of nuclear power plants, and uses the working mechanism of EMAT to continuously monitor the physical properties of in-service high-temperature equipment in nuclear power plants. To avoid the sound velocity error caused by temperature, by fitting the ultrasonic sound velocity values within the temperature conditions and obtaining the temperature influence coefficient based on the normal-temperature standard sound velocity, the sound velocity error caused by high temperature is eliminated. Finally, combining the shear wave velocity and longitudinal wave velocity simultaneously excited by EMAT, the compensated and corrected shear wave velocity and longitudinal wave velocity are used to monitor key physical property parameters such as elastic modulus and Poisson's ratio of in-service equipment in nuclear power plants in a high-temperature environment, and a real-time and effective assessment of potential risks that may exist is made.

[0015] Furthermore, different from traditional piezoelectric ultrasonic detection, the design of the EMAT probe to simultaneously excite ultrasonic shear waves and longitudinal waves specifically includes: EMAT has the advantages of non-contact and no need for a coupling agent, and its flexible magnetic field composition enables it to excite multi-modal ultrasonic wave types according to measurement requirements. The static magnetic field provided by the permanent magnet and the dynamic magnetic field generated by the coil show a diverse distribution in space.

[0016] Furthermore, the static magnetic field provided by the permanent magnet and the dynamic magnetic field generated by the coil exhibit diverse distributions in space, specifically including: the dynamic magnetic field generated by the coil only exists on the surface of the medium, and the induced eddy current is always parallel to the surface of the medium. In the permanent magnet, a bias magnetic field in the vertical direction is mainly generated in the area directly below, which causes particle vibrations parallel to the surface of the medium and perpendicular to the ultrasonic propagation direction after interacting with the dynamic magnetic field, thereby exciting transverse waves; on both sides of the permanent magnet, a bias magnetic field in the horizontal direction is provided, prompting the particles to vibrate perpendicular to the surface of the medium and parallel to the ultrasonic propagation direction, and then exciting longitudinal waves.

[0017] Furthermore, the high-temperature resistant design of the EMAT sensor specifically includes: selecting samarium cobalt magnets as the permanent magnet, with a maximum operating temperature of up to 350 °C. For the coil part, a butterfly coil is selected, and the coil is filled by means of die processing. The outside of the die is sintered with ceramics. A silver sheet is placed between the magnet and the coil for electromagnetic shielding. A ceramic sheet is placed below the coil as a wear-resistant layer, and at the same time, further heat insulation treatment is carried out. The sensor housing is made of 316 stainless steel, and the probe wiring is insulated with a fiberglass sleeve. The gap between the housing, the magnet, and the coil is filled with ceramic adhesive to stabilize the internal structure of the sensor and further effectively insulate heat.

[0018] Furthermore, different from the EMAT detection at normal temperature, the present invention uses the least squares method to fit the linear relationship between the ultrasonic sound velocity and the detection temperature, and obtains the relationship formula V T = aT + b, where V T is the sound velocity value after compensation at the detection temperature, a is the regression coefficient, representing the rate of change of the ultrasonic sound velocity with temperature; b is the intercept, representing the sound velocity value when the temperature T is 0; T is the temperature detected on the surface of the in-service equipment; the ultrasonic sound velocity compensation and correction in the high-temperature environment specifically include:

[0019] First, in combination with the application scenario of nuclear power in-service equipment, the temperature working condition range is set from 25 °C to 350 °C;

[0020] Second, to ensure the accuracy of ultrasonic sound velocity measurement, within the set temperature working conditions, the ultrasonic sound velocity (including ultrasonic shear wave velocity and ultrasonic longitudinal wave velocity) is measured every 1 °C;

[0021] Third, measure the corresponding ultrasonic shear and longitudinal wave velocity values at multiple temperature points respectively to obtain a series of data, and use the least squares method to fit the ultrasonic shear and longitudinal wave velocities within the set temperature working condition range to obtain the compensated ultrasonic shear wave value Vs and the compensated ultrasonic longitudinal wave value Vp.

[0022] Taking 20# steel as an example, the fitted formula is as follows:

[0023] V s= -0.51776T + 3256.5595

[0024] V p = -0.82755T + 5968.4119

[0025] In the formula, V s is the shear wave sound velocity corresponding to temperature T, V p is the longitudinal wave sound velocity corresponding to temperature T, and T is the workpiece surface temperature.

[0026] Furthermore, different from the normal temperature EMAT detection, the ultrasonic sound velocity compensation under the high temperature environment specifically includes: dividing the ultrasonic sound velocity V T (the shear wave sound velocity is denoted as V s , and the longitudinal wave sound velocity is denoted as V p、 sound velocity 、 ) at different temperatures by the standard sound velocity V 0 without the influence of high temperature (normal temperature) to obtain the influence coefficient f(T) of temperature on the ultrasonic sound velocity at different temperatures. The formula is as follows:

[0027]

[0028] In the formula, f(T) is the temperature influence coefficient, V is the ultrasonic sound velocity corresponding to temperature T, and V 0 is the ultrasonic sound velocity at normal temperature.

[0029] Furthermore, different from the normal temperature EMAT detection, the ultrasonic sound velocity correction under the high temperature environment specifically includes: using the temperature coefficient formula obtained by fitting to establish the corresponding relationship between the current temperature and the ultrasonic sound velocity at this temperature to achieve temperature compensation. The formula is as follows:

[0030] V T = V 0 * f(T)

[0031] In the formula, V 0 is the ultrasonic sound velocity at normal temperature, and V T is the ultrasonic sound velocity after temperature compensation.

[0032] Furthermore, different from the physical property detection at normal temperature, the shear wave and longitudinal wave sound velocity data excited by the EMAT probe are used to continuously monitor the key physical property parameters such as elastic modulus and Poisson's ratio of in-service equipment in a high-temperature environment. Specifically, it includes: based on the design of an EMAT high-temperature-resistant sensor, and the characteristic that EMAT can excite multi-modal waveforms, it is possible to continuously collect the shear wave and longitudinal wave sound velocity data inside the in-service equipment of a nuclear power plant under high-temperature conditions, and use the temperature compensation formula to correct the ultrasonic sound velocity error under high-temperature conditions, and finally calculate the elastic modulus and Poisson's ratio to achieve continuous monitoring of physical properties in a high-temperature environment. Since the material density is less affected by high temperature, the standard density at normal temperature can be used. The specific calculation formula is as follows:

[0033]

[0034] In the formula, E is the elastic modulus of the material, u is the Poisson's ratio of the material, ρ is the material density, V p is the longitudinal wave propagation sound velocity, V s

[0035] is the shear wave propagation sound velocity.

[0036] 3. Beneficial effects

[0037] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0038] (1) The monitoring method of the present invention is based on an EMAT sensor. Utilizing the characteristic that the EMAT sensor can withstand high temperatures for a long time, it fits the ultrasonic sound velocity data corresponding to each degree within the required temperature working condition of the EMAT sensor, and combines with the standard sound velocity at normal temperature to obtain the temperature influence coefficient at different temperatures, and finally establishes the corresponding relationship between temperature and ultrasonic sound velocity, correcting the sound velocity value in a high-temperature environment and effectively avoiding measurement errors caused by high temperature.

[0039] (2) The temperature influence coefficient obtained by experimental fitting in the present invention can obtain accurate shear and longitudinal wave sound velocities in a high-temperature environment, and then continuously monitor key physical property parameters such as elastic modulus and Poisson's ratio in a high-temperature environment, realizing non-destructive and continuous monitoring of high-temperature in-service equipment in a nuclear power plant, providing a strong basis for the in-service safety of key equipment in a nuclear power plant.

[0040] (3) The present invention uses an EMAT sensor, which does not require a coupling agent, has low requirements for the surface of the workpiece to be measured, and the designed EMAT sensor has a maximum heat-resistant temperature of 350 °C, which is suitable for high-temperature application scenarios in a nuclear power plant and can meet the monitoring requirements in harsh environments. Compared with traditional ultrasonic detection methods, the present invention can continuously monitor the physical properties of in-service equipment in a high-temperature environment without complex design, which is efficient and convenient. Description of the drawings

[0041] Figure 1 Flow chart of the physical property monitoring method in a high-temperature environment according to an embodiment of the present invention;

[0042] Figure 2 Waveform diagram of the transverse and longitudinal waves excited by EMAT in an embodiment of the present invention;

[0043] Figure 3 Schematic diagram of a high-temperature resistant EMAT sensor in an embodiment of the present invention;

[0044] In the figure:

[0045] 1. Magnet; 2. Coil; 3. Wear-resistant layer; 4. Ceramic adhesive; 5. Silver sheet; 6. Glass fiber sleeve; 7. Shell; Specific implementation manner

[0046] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0047] As Figure 1 shown, this embodiment provides a method for monitoring the physical properties of in-service equipment in a nuclear power plant at high temperature, including:

[0048] Design an EMAT probe to simultaneously excite ultrasonic transverse and longitudinal waves;

[0049] High-temperature resistant design of the EMAT sensor;

[0050] Ultrasonic sound speed compensation and correction in a high-temperature environment;

[0051] Utilize the transverse and longitudinal wave sound speed data excited by the EMAT probe to continuously monitor key physical property parameters such as elastic modulus and Poisson's ratio of the in-service equipment in a high-temperature environment.

[0052] Specifically, based on the EMAT detection principle, the present invention designs a high-temperature resistant EMAT sensor for the special application scenario of a nuclear power plant. As Figure 3As shown in the figure, the EMAT sensor of this embodiment is designed to be heat-resistant, specifically including: selecting samarium cobalt magnet as the heat-resistant magnet 1, whose maximum operating temperature can reach 350 °C, selecting a butterfly coil for the coil 2 part, filling the coil 2 by means of die processing, sintering ceramics on the outside of the die, putting a silver sheet 5 between the magnet and the coil for electromagnetic shielding, putting a ceramic sheet under the coil as a wear-resistant layer 3, and further performing heat insulation treatment at the same time. The sensor housing 7 is made of 316 stainless steel, and the probe wiring part is heat-insulated with a fiberglass sleeve 6. The gap between the housing 7, the magnet, and the coil 2 is filled with a ceramic adhesive 4 to further effectively insulate while stabilizing the internal structure of the sensor.

[0053] In addition, combined with Figure 2 , the EMAT sensor probe designed in this embodiment simultaneously excites ultrasonic shear waves and longitudinal waves. Taking advantage of the non-contact and non-coupling agent characteristics of EMAT, its flexible magnetic field composition enables it to generate multi-modal ultrasonic waveforms according to measurement requirements. The static magnetic field provided by the permanent magnet and the dynamic magnetic field generated by the coil show diverse distributions in space.

[0054] The dynamic magnetic field generated by the coil only exists on the surface of the medium, and the induced eddy current is always parallel to the surface of the medium. In the permanent magnet, a vertical bias magnetic field is mainly generated in the area directly below. After interacting with the dynamic magnetic field, it causes particle vibrations parallel to the surface of the medium and perpendicular to the ultrasonic propagation direction, thus exciting shear waves; on both sides of the permanent magnet, a horizontal bias magnetic field is provided, prompting the particles to vibrate perpendicular to the surface of the medium and parallel to the ultrasonic propagation direction, thereby exciting longitudinal waves.

[0055] The applicant has found through research that when using an EMAT sensor to continuously monitor the physical properties of in-service equipment in a nuclear power plant, due to the special application scenario of the nuclear power plant (higher temperature), the direct monitoring error is relatively large. To avoid the sound speed error caused by temperature, by fitting the ultrasonic sound speed values within the temperature condition and obtaining the temperature influence coefficient based on the normal temperature standard sound speed, the sound speed error caused by high temperature is eliminated. Finally, by combining the shear wave and longitudinal wave sound speeds simultaneously excited by EMAT and using the temperature compensation formula to correct the ultrasonic sound speed error under high temperature conditions, the key physical property parameters such as elastic modulus and Poisson's ratio of the in-service equipment in the nuclear power plant in a high temperature environment can be monitored, and real-time and effective assessment of potential risks that may exist can be made.

[0056] Compensate and correct the ultrasonic sound velocity at high temperatures. In this embodiment, the EMAT sensor is connected to the workpiece to be measured, a K-type thermocouple is placed on the surface of the workpiece, and the surface temperature of the workpiece is used as the standard. In this embodiment, the temperature condition is specifically set to 350 °C, and the ultrasonic sound velocity is recorded degree by degree to obtain a series of data (T, V). As the temperature rises, the ultrasonic sound velocity excited by the EMAT shows a monotonic decrease. Taking the measurement result of 20# steel as an example, the ultrasonic shear and longitudinal wave velocities within the set temperature condition (350 °C) are fitted using the least squares method. Taking 20# steel as an example, the fitted formula is as follows:

[0057] V s =-0.51776T + 3256.5595

[0058] V p =-0.82755T + 5968.4119

[0059] In the formula, V s is the shear wave velocity corresponding to the temperature T, V p is the longitudinal wave velocity corresponding to the temperature T, and T is the surface temperature of the workpiece.

[0060] In this embodiment, the compensation of the ultrasonic sound velocity in a high-temperature environment specifically includes: dividing the ultrasonic sound velocity V T at different temperatures by the standard sound velocity V 0 without the influence of high temperature (room temperature) to obtain the influence coefficient f(T) of temperature on the ultrasonic sound velocity at different temperatures. The formula is as follows:

[0061]

[0062] In the formula, f(T) is the temperature influence coefficient, V T is the ultrasonic sound velocity (such as shear wave or longitudinal wave) corresponding to the temperature T, and V 0 is the ultrasonic sound velocity at room temperature. Using this method can compensate the ultrasonic shear and longitudinal wave values measured at high temperatures, so as to accurately monitor the physical properties of in-service equipment in nuclear power plants.

[0063] It should be noted that to ensure the accuracy of the shear wave velocity calibration at 25 °C room temperature, the sensor is connected to the workpiece and placed in a constant temperature chamber to measure the shear wave velocity, avoiding the local temperature difference caused by heat flow and temperature gradient. Thus, an ideal room temperature condition can be obtained. The sound velocity data is processed by the circuit module and displayed on the PC side. The average value of 10 measurement values is taken as the final calibration value V 0 .

[0064] Using the temperature coefficient formula obtained after fitting, establish the corresponding relationship between the current temperature and the ultrasonic sound velocity at this temperature to achieve temperature compensation. The formula is as follows:

[0065] VT = V 0 * f(T)

[0066] Wherein, V 0 is the ultrasonic sound velocity at room temperature (including shear wave or longitudinal wave), and V T is the ultrasonic sound velocity after temperature compensation.

[0067] The present invention utilizes the shear wave and longitudinal wave sound velocity data excited by an EMAT probe to continuously monitor key physical property parameters such as elastic modulus and Poisson's ratio of in-service equipment in a high-temperature environment. Specifically, it includes: a sensor design based on the high-temperature resistance of EMAT, and the characteristic that EMAT can excite multi-modal waveforms, which can continuously collect the shear wave and longitudinal wave sound velocity data inside the in-service equipment of a nuclear power plant under high-temperature conditions, and correct the ultrasonic sound velocity error under high-temperature conditions using a temperature compensation formula. Finally, the elastic modulus and Poisson's ratio are calculated to achieve continuous monitoring of the physical properties of in-service equipment in a high-temperature environment. Since the material density is less affected by high temperature, the standard density at room temperature can be used. The specific calculation formula is as follows:

[0068]

[0069] Wherein, E is the elastic modulus of the material, u is the Poisson's ratio of the material, ρ is the density of the material, and V p is the longitudinal wave propagation sound velocity, and V s is the shear wave propagation sound velocity.

[0070] Taking 20# steel as the monitoring object, Table 1 shows some elastic modulus and Poisson's ratio data of this workpiece in a high-temperature environment.

[0071] Table 1 Monitoring results of physical properties in a high-temperature environment

[0072] Temperature / °C Shear wave velocity / (m / s) Longitudinal wave velocity / (m / s) Elastic modulus / GPa Poisson's ratio 25 3237 5939 212 0.289 100 3206 5885 208 0.289 150 3183 5841 205 0.289 200 3158 5808 202 0.290 250 3130 5792 199 0.294 300 3101 5717 195 0.292 350 3069 5659 191 0.292

[0073] According to the above technical solution of the embodiment of the present invention, by designing a high-temperature-resistant EMAT sensor and using the working mechanism of EMAT to continuously monitor the physical properties of in-service high-temperature equipment in a nuclear power plant. To avoid the sound velocity error caused by temperature, by fitting the ultrasonic sound velocity values within the temperature condition and obtaining the temperature influence coefficient based on the standard sound velocity at room temperature, the sound velocity error caused by high temperature is eliminated. Finally, combining the shear wave and longitudinal wave sound velocities simultaneously excited by EMAT, key physical property parameters such as elastic modulus and Poisson's ratio of in-service equipment in a nuclear power plant in a high-temperature environment are monitored, providing a strong basis for the safe operation of in-service nuclear power plant equipment.

[0074] Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for monitoring the physical properties of in-service equipment in a nuclear power plant based on EMAT, characterized in that: include: The EMAT probe is designed to excite ultrasonic transverse and longitudinal waves simultaneously; High temperature resistant design of EMAT sensor; Compensation and correction of shear wave and longitudinal wave velocities excited by EMAT probe in high temperature environment; The compensated and corrected shear wave sound velocity data and longitudinal wave sound velocity data are used to continuously monitor the physical performance parameters of in-service equipment in high temperature environments.

2. The monitoring method according to claim 1, characterized in that: The high temperature resistant design of the EMAT sensor includes selecting a samarium cobalt magnet as a permanent magnet (1), selecting a butterfly coil as a coil (2), using 316 stainless steel for the housing (7), and using a glass fiber sleeve (6) at the probe wiring point.

3. The monitoring method according to claim 2, characterized in that: The coil (2) is filled by mold processing, the outside of the mold is sintered with ceramics, a ceramic sheet is placed under the coil (2) as a wear-resistant layer (3), and the gap between the shell (7) and the magnet (1) and the coil (2) is filled with a ceramic adhesive (4).

4. The monitoring method according to claim 1, characterized in that: The specific method of ultrasonic sound velocity compensation and correction in high temperature environment is as follows: the linear relationship between ultrasonic sound velocity and detection temperature is fitted by the least square method, and the relationship V is obtained. T =aT+b,V T is the sound velocity value after compensation at the detection temperature, a is the regression coefficient, which indicates the rate at which the ultrasonic sound velocity changes with temperature, b is the intercept, which indicates the sound velocity value when the temperature T is 0, and T is the temperature detected on the surface of the in-service equipment; then V T By comparing with the standard sound velocity V0 at room temperature, the influence coefficient of temperature on ultrasonic sound velocity f(T) is obtained, and the formula is as follows: Where f(T) is the temperature influence coefficient, V T is the ultrasonic sound velocity corresponding to temperature T, and V0 is the ultrasonic sound velocity at room temperature.

5. The monitoring method according to claim 4, characterized in that: Specifically, the ultrasonic sound velocity compensation and correction steps are as follows: First, set the detection temperature operating range based on the application scenarios of nuclear power equipment in service; Second, to ensure the accuracy of ultrasonic sound velocity measurement, the ultrasonic sound velocity is measured every 1°C within the set temperature range; Third, the ultrasonic transverse and longitudinal wave sound velocity values ​​corresponding to multiple temperature points are measured respectively to obtain a series of data. The ultrasonic transverse and longitudinal wave sound velocities within the set temperature operating range are fitted using the least squares method to obtain the compensated ultrasonic transverse wave value Vs and the compensated ultrasonic longitudinal wave value Vp.

6. The monitoring method according to claim 5, characterized in that: The physical performance parameters of the in-service equipment tested include elastic modulus and Poisson's ratio.

7. The monitoring method according to claim 6, characterized in that: The elastic modulus of the in-service equipment is calculated using the compensated and corrected ultrasonic sound velocity, and the formula is as follows: In the formula, E is the elastic modulus of the material, ρ is the material density, V p is the speed of sound of longitudinal wave propagation, V s is the speed of sound for shear wave propagation.

8. The monitoring method according to claim 6, characterized in that: The Poisson's ratio of the in-service equipment is calculated using the compensated and corrected ultrasonic sound velocity, and the formula is as follows: Where u is the Poisson's ratio of the material, V p is the speed of sound of longitudinal wave propagation, V s is the speed of sound for shear wave propagation.

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