Method for rapidly detecting and evaluating aging of heat-resistant steel

Abstract

The invention relates to the aging detection content of electric and thermal heat-resistant steel pipes in the fields of nondestructive testing and physical and chemical inspection, in particular to a method for quickly detecting and evaluating the aging of heat-resistant steel, which comprises the following steps: selecting and manufacturing a metallographic analysis sample and a corresponding ultrasonic detection sample according to the information of a heat-resistant steel pipe to be detected; respectively obtaining the aging level and acoustic performance data of the sample through metallographic analysis and ultrasonic detection; establishing a database of the relationship between the sample aging level and the acoustic performance data; actual engineering detection is carried out to obtain acoustic performance data of the detected pipe, and the aging level and safety reliability of the detected pipe are searched and determined by a database, so that the pipes which can be continuously used and / or the pipes which need to be replaced due to serious aging are determined; therefore, the problems that a metallographic analysis method is tedious and complex in process, low in detection working efficiency, prone to causing health hazards and the like are solved, and the problems that other non-metallographic analysis methods are low in detection reliability and cannot meet actual engineering requirements and the like are solved.

Description

Technical Field

[0001] The present application relates to the technical content of aging detection of heat-resistant steel in power engineering and thermal engineering in the field of non-destructive testing and physical and chemical testing, and in particular to a method for quickly detecting and evaluating aging of heat-resistant steel. Background Art

[0002] To ensure the safety of life and property, the state has designated high-temperature, high-pressure thermal equipment, such as boilers, pressure vessels, and pressure piping, used in the power, energy, and chemical industries, as special equipment for regulatory oversight. A key component of this technical oversight is preventing heat-resistant steel high-temperature, high-pressure components from experiencing structural and performance degradation and failure under high-temperature, high-pressure conditions, which could affect the normal operation of thermal equipment and lead to serious accidents.

[0003] In related technologies, the aging of heat-resistant steel can be inspected and evaluated by metallographic analysis or by combining metallographic analysis with mechanical property tests. The metallographic analysis method inspects and evaluates the aging of heat-resistant steel through sampling, sample preparation, microscopic observation and analysis, and photography. The aging of heat-resistant steel can also be evaluated by some non-metallographic analysis methods, such as laser spectroscopy measurement calculations, magnetic state and oxide scale thickness, polarization curves, test data, etc.

[0004] However, among the related technologies, the metallographic analysis method has reliable test results, but the sample preparation process is cumbersome and time-consuming, and may produce health hazards such as dust, mechanical trauma, and chemicals during grinding, which lacks convenience and environmental protection; while the non-metallographic analysis method can easily ignore the influence of the initial state and other related factors, resulting in a large deviation between the predicted life and the actual engineering. Its reliability needs to be verified, and it cannot meet the actual use needs and is in urgent need of improvement. Summary of the Invention

[0005] The present application provides a method for rapidly detecting and evaluating the aging of heat-resistant steel to address the problems in related technologies, such as the cumbersome and time-consuming metallographic analysis method, which is prone to health hazards during sample preparation and polishing, and lacks convenience and environmental friendliness; and other non-metallographic analysis methods, whose detection effects and reliability need to be verified, cannot meet the actual use needs of engineering projects.

[0006] The first embodiment of the present application provides a method for quickly detecting and evaluating the aging of heat-resistant steel, comprising the following steps: based on information about steel pipes used in thermal equipment to be inspected, collecting heat-resistant steel pipe samples of relevant specifications and steel grades, and making the heat-resistant steel pipe samples into metallographic analysis samples and corresponding ultrasonic inspection samples; performing metallographic analysis on the metallographic analysis samples to determine the aging level of the metallographic analysis samples; performing ultrasonic inspection on the ultrasonic inspection samples to obtain ultrasonic acoustic performance parameters of the ultrasonic inspection samples; based on the aging level of the metallographic analysis samples and the ultrasonic acoustic performance parameters of the ultrasonic inspection samples, establishing a database of the relationship between the aging level of the heat-resistant steel pipe samples and the corresponding ultrasonic acoustic performance parameters; carrying out actual engineering inspections to obtain the ultrasonic acoustic performance parameters of the heat-resistant steel pipes of the thermal equipment inspected in the actual engineering, determining the aging level of the inspected heat-resistant steel pipes by searching the database, and determining the safety and reliability of the inspected heat-resistant steel pipes in the actual engineering based on the aging level of the inspected heat-resistant steel pipes, so as to determine which heat-resistant steel pipes in the thermal equipment can continue to be used and / or which heat-resistant steel pipes are severely aged and need to be replaced.

[0007] Through the above technical scheme, based on the information of the steel pipes used in the thermal equipment to be inspected, heat-resistant steel pipe samples of relevant specifications and steel types can be collected, and corresponding metallographic analysis samples and ultrasonic inspection samples can be made. The aging level of the metallographic analysis sample and the ultrasonic acoustic performance parameters of the ultrasonic inspection sample can be determined through metallographic analysis and ultrasonic inspection respectively, and then a database of the relationship between the aging level of the heat-resistant steel pipe sample and the corresponding ultrasonic acoustic performance parameters is established. When carrying out actual engineering inspections, the corresponding aging level is determined by searching the database according to the ultrasonic acoustic performance parameters of the inspected heat-resistant steel pipe, and the safety and reliability of the inspected heat-resistant steel pipe is determined, and then it is determined which heat-resistant steel pipes in the thermal equipment can continue to be used and / or which heat-resistant steel pipes need to be replaced. Aging detection of heat-resistant steel pipes of thermal equipment can be realized through ultrasonic inspection, the inspection speed is improved, the safety and reliability of heat-resistant steel pipes of thermal equipment are ensured, and the unplanned downtime losses of thermal equipment are reduced, the replacement cycle of heat-resistant steel pipes is accurately arranged, and costs are saved.

[0008] Optionally, in one embodiment of the present application, based on the information of the steel pipes used in the thermal equipment to be inspected, heat-resistant steel pipe samples of relevant specifications and steel grades are collected, and the heat-resistant steel pipe samples are made into metallographic analysis samples and corresponding ultrasonic inspection samples, including: preparing a preset number of pipe samples based on the heat-resistant steel pipes of the relevant specifications and steel grades, wherein the specifications and steel grades of the pipe samples are consistent with the pipes of the thermal equipment, and the aging range of the pipe samples includes various aging levels; processing the pipe samples, and making each pipe into a metallographic analysis sample and a corresponding ultrasonic inspection sample, wherein the length of the ultrasonic inspection sample meets the requirements of ultrasonic inspection.

[0009] Through the above technical solution, a certain number of pipe samples with the same specifications and steel grades as the thermal equipment are prepared to obtain pipe samples containing various aging levels. The pipe samples are then processed and each pipe is made into a corresponding metallographic analysis sample and ultrasonic testing sample.

[0010] Optionally, in one embodiment of the present application, the ultrasonic testing of the ultrasonic testing sample includes: cleaning and polishing the surface of the ultrasonic testing sample to meet the needs of ultrasonic testing; selecting the type and parameters of the sensor according to the outer diameter parameters and wall thickness parameters of the ultrasonic testing sample, and setting the distance between the two sensors.

[0011] Through the above technical solution, the surface can be cleaned and polished during ultrasonic testing to meet the needs of ultrasonic testing. The type and parameters of the sensor are selected according to the outer diameter parameters and wall thickness parameters of the ultrasonic testing sample, and the distance between the two sensors is set. By cleaning and polishing the surface, dirt, oxide layer and rough parts on the surface of the sample are removed, the accuracy and reliability of ultrasonic testing are improved, and the scattering and attenuation of ultrasonic waves are reduced. The reliability of detection is ensured by selecting sensors and setting the distance between the two serial sensors.

[0012] Optionally, in one embodiment of the present application, the ultrasonic detection of the ultrasonic detection sample includes: determining an ultrasonic frequency that meets preset working conditions based on the ultrasonic detection sample; selecting an ultrasonic instrument that can operate within the frequency range based on the ultrasonic frequency; determining a coupling agent material and / or a scanning method based on the ultrasonic frequency, the ultrasonic instrument, and the type and parameters of the sensor; and performing the ultrasonic detection based on the working frequency, the coupling material and / or the scanning method.

[0013] Through the above technical solution, the ultrasonic frequency that meets certain working conditions can be determined based on the ultrasonic test sample, and then an ultrasonic instrument that can work within the frequency range can be selected, and the coupling agent material and / or scanning method can be determined, so as to reliably perform ultrasonic testing.

[0014] Optionally, in one embodiment of the present application, before performing ultrasonic testing on the ultrasonic test sample, it also includes: testing the refraction angle or K value of the selected sensor; measuring the incident point position of the sensor on a standard test block, and marking the incident point position on the sensor; making an arc surface of the sensor detection surface according to the outer cylindrical surface of the pipe, ensuring that the detection surface is consistent with the outer cylindrical surface of the pipe being detected, and ensuring the directionality of the sensor's sound beam; making a clamping device for the sensor, ensuring that the sensor fits the pipe, and the two sensors used in series move synchronously and stably, and maintain a constant pressure between the pipe to ensure the accuracy of the test results; and designing the sensor spacing to be flexibly adjusted.

[0015] Through the above technical scheme, the refraction angle or K value of the sensor and the position of the incident point can be selected according to the comparative test results, and the arc surface of the sensor detection surface can be made according to the outer cylindrical surface of the pipe to ensure that the detection surface is well matched with the outer cylindrical surface of the pipe being detected, reduce the scattering and attenuation of sound waves, and improve the detection reliability; test the sound beam directionality of the selected sensor to ensure that the sound beam directionality of the sensor is good; make a clamping device to ensure that the sensor fits well with the pipe, and the two sensors used in series move synchronously and stably, and maintain a constant pressure between the pipe to ensure the accuracy of the detection results. The sensor spacing is designed to be flexibly adjusted, and the sensor spacing is adjusted according to different detection requirements to improve the flexibility and efficiency of detection.

[0016] Optionally, in one embodiment of the present application, the ultrasonic testing of the ultrasonic test sample to obtain the ultrasonic acoustic performance parameters of the ultrasonic test sample includes: obtaining the steel grade information and specification information corresponding to the heat-resistant steel pipe sample; obtaining the original spare pipe sample and the pipe samples with different aging levels through the steel grade information; performing ultrasonic testing on the original spare pipe sample to obtain the ultrasonic acoustic performance parameters of the unaged heat-resistant steel pipe sample; performing ultrasonic testing on the pipe samples with different aging levels to obtain the ultrasonic acoustic performance parameters corresponding to the heat-resistant steel pipe samples with different aging levels.

[0017] Through the above technical solution, original spare pipe samples and pipe samples with different aging levels can be obtained according to the steel type information and specification information corresponding to the heat-resistant steel pipe samples, and then the above pipe samples can be ultrasonically tested to obtain the ultrasonic acoustic performance parameters corresponding to the non-aged heat-resistant steel pipe samples and the heat-resistant steel pipe samples with different aging levels. By obtaining the steel type information and specification information of the heat-resistant steel pipe samples, the pertinence and accuracy of the detection are ensured. By obtaining the original spare pipe samples, a basis is provided for evaluating the microstructural state of the aged steel pipe, and then the influence of aging on the acoustic performance is studied, and the aging state of the steel pipe is evaluated.

[0018] Optionally, in one embodiment of the present application, the actual engineering inspection is carried out to obtain the ultrasonic acoustic performance parameters of the heat-resistant steel pipes of the thermal equipment inspected in the actual engineering, the aging level of the inspected heat-resistant steel pipes is determined by searching the database, and the safety and reliability of the inspected heat-resistant steel pipes in the actual engineering are determined based on the aging level of the inspected heat-resistant steel pipes, so as to determine which heat-resistant steel pipes in the thermal equipment can continue to be used and / or which heat-resistant steel pipes are severely aged and need to be replaced, including: carrying out actual engineering inspection, performing ultrasonic inspection on the heat-resistant steel pipes of the thermal equipment, and obtaining the ultrasonic acoustic performance parameters of the heat-resistant steel pipes of the thermal equipment; determining the aging level of the heat-resistant steel pipes of the thermal equipment by searching the database based on the ultrasonic acoustic performance parameters of the heat-resistant steel pipes of the thermal equipment; determining the safety and reliability of the heat-resistant steel pipes of the thermal equipment according to the aging level of the heat-resistant steel pipes of the thermal equipment, so as to determine which heat-resistant steel pipes in the thermal equipment can continue to be used and / or which are severely aged and need to be replaced.

[0019] Through the above technical solution, when carrying out actual engineering inspections, ultrasonic inspections can be performed on the heat-resistant steel pipes of the thermal equipment being inspected, and the corresponding ultrasonic acoustic performance parameters can be obtained. The corresponding aging level can be determined by searching the database, and the safety and reliability of the heat-resistant steel pipes of the thermal equipment being inspected can be determined. It can also be determined which heat-resistant steel pipes of the thermal equipment can continue to be used and / or which heat-resistant steel pipes need to be replaced due to severe aging, so as to ensure the safety, reliability and economy of the thermal equipment.

[0020] The embodiment of the present application can collect heat-resistant steel pipe samples of relevant specifications and steel grades based on the information of the steel pipes used in the thermal equipment to be inspected, and make corresponding metallographic analysis samples and ultrasonic testing samples. The aging level of the metallographic analysis sample and the ultrasonic acoustic performance parameters of the ultrasonic testing sample are determined through metallographic analysis and ultrasonic testing, respectively. Then, a database of the relationship between the aging level of the heat-resistant steel pipe samples and the corresponding ultrasonic acoustic performance parameters is established. When carrying out actual engineering inspections, the corresponding aging level is determined by searching the database based on the ultrasonic acoustic performance parameters of the heat-resistant steel pipes of the thermal equipment to be inspected, and the safety and reliability of the heat-resistant steel pipes of the thermal equipment to be inspected are determined. Then, which heat-resistant steel pipes of the thermal equipment can continue to be used and / or which heat-resistant steel pipes need to be replaced due to severe aging are determined, thereby improving the safety and reliability of the thermal equipment, reducing unplanned downtime losses, accurately arranging replacement cycles, and saving costs. Thus, the problems in the related art that the metallographic analysis method is cumbersome, the inspection work efficiency is low, and it is easy to cause health hazards during sample preparation and polishing; and other non-metallographic analysis methods have detection reliability that needs to be verified.

[0021] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0023] Figure 1 This is a flow chart of a method for rapidly detecting and evaluating aging of heat-resistant steel provided in accordance with an embodiment of the present application;

[0024] Figure 2 This is a flow chart of performing ultrasonic testing according to one embodiment of the present application;

[0025] FIG3( a ) is a flow chart of single-probe reflection measurement according to one embodiment of the present application;

[0026] FIG3( b ) is a flow chart of a dual-probe serial scanning method measurement according to one embodiment of the present application;

[0027] Figure 4 A flow chart of a serial scanning test according to one embodiment of the present application;

[0028] Figure 5 The present invention is a flowchart of the working principle of the method for rapid detection and evaluation of aging of heat-resistant steel provided according to one embodiment of the present application. DETAILED DESCRIPTION

[0029] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0030] The following describes, with reference to the accompanying drawings, a method for rapidly detecting and evaluating aging of heat-resistant steel according to an embodiment of the present application. The metallographic analysis method mentioned in the background art is cumbersome, inefficient, and prone to health hazards during sample preparation and polishing. The reliability of other non-metallographic analysis methods remains to be verified. The present application provides a method for rapidly detecting and evaluating the aging of heat-resistant steel. In this method, based on the information of the steel pipes used in the thermal equipment to be inspected, heat-resistant steel pipe samples of relevant specifications and steel grades can be collected and made into corresponding metallographic analysis samples and ultrasonic testing samples. The aging level of the metallographic analysis sample and the ultrasonic acoustic performance parameters of the ultrasonic testing sample are determined by metallographic analysis and ultrasonic testing, respectively. Then, a database of the relationship between the aging level of the heat-resistant steel pipe samples and the corresponding ultrasonic acoustic performance parameters is established. When carrying out actual engineering inspections, the corresponding aging level is determined by searching the database based on the ultrasonic acoustic performance parameters of the heat-resistant steel pipes of the thermal equipment to be inspected, and the safety and reliability of the heat-resistant steel pipes of the thermal equipment to be inspected are determined. Then, which heat-resistant steel pipes of the thermal equipment can continue to be used and / or which heat-resistant steel pipes need to be replaced due to severe aging, thereby improving the safety and reliability of the thermal equipment, reducing unplanned downtime losses, and saving costs. Thus, the method solves the problems in the related art that the metallographic analysis method is cumbersome and time-consuming, and is prone to health hazards during sample preparation and polishing; and other non-metallographic analysis methods have detection effects and reliability that need to be verified.

[0031] Specifically, Figure 1 The present invention provides a flowchart of a method for rapidly detecting and evaluating aging of heat-resistant steel according to an embodiment of the present application.

[0032] like Figure 1 As shown, the method for rapid detection and evaluation of heat-resistant steel aging includes the following steps:

[0033] In step S101, based on the information of the steel pipes used in the thermal equipment to be inspected, heat-resistant steel pipe samples of relevant specifications and steel types are collected, and the heat-resistant steel pipe samples are made into metallographic analysis samples and corresponding ultrasonic testing samples.

[0034] It can be understood that in the embodiment of the present application, the information of the steel pipe used in the thermal equipment to be tested may include but is not limited to the specifications and steel types of the steel pipe. Furthermore, in the embodiment of the present application, the specifications may include the outer diameter and wall thickness of the steel pipe, etc., and the present application does not impose specific restrictions; the steel type may include pearlite heat-resistant steel, martensite heat-resistant steel, austenitic stainless steel, etc., and the present application does not impose specific restrictions.

[0035] As a possible implementation method, the embodiment of the present application can make the heat-resistant steel pipe sample into a metallographic analysis sample and a corresponding ultrasonic detection sample based on the information of the steel pipe used in the thermal equipment to be detected. The main content is: the embodiment of the present application can determine the specifications and steel type of the heat-resistant steel pipe sample based on the information of the steel pipe used in the thermal equipment to be detected, and process the heat-resistant steel pipe sample to obtain metallographic analysis samples and corresponding ultrasonic detection samples of different aging levels to meet the needs of actual engineering detection.

[0036] For example, in this embodiment of the present application, representative tubes can be selected based on a comprehensive visual inspection and expansion measurement of a boiler's high-temperature superheater, and samples of approximately 500 mm in length can be cut. For example, a 500 mm section can be taken from each of the tubes that appear to be unaged or slightly aged, as well as moderately aged and severely aged, as indicated by both appearance and expansion measurement. From each of these sections, 20 mm to 30 mm sections can be cut as metallographic analysis samples. The remaining 470 mm to 480 mm section can be used as ultrasonic testing samples. Identification marks can be made on each sample.

[0037] Optionally, in one embodiment of the present application, based on information about steel pipes used in the thermal equipment to be inspected, heat-resistant steel pipe samples of relevant specifications and steel grades are collected, and the heat-resistant steel pipe samples are made into metallographic analysis samples and corresponding ultrasonic inspection samples, including: preparing a preset number of pipe samples based on the heat-resistant steel pipes of relevant specifications and steel grades, wherein the specifications and steel grades of the pipe samples are consistent with the pipes of the thermal equipment, and the aging range of the pipe samples includes various aging levels; processing the pipe samples, and making each pipe into a metallographic analysis sample and a corresponding ultrasonic inspection sample, wherein the length of the ultrasonic inspection sample meets the requirements of ultrasonic inspection.

[0038] It is understood that in the embodiments of this application, when preparing metallographic analysis specimens and corresponding ultrasonic testing specimens, the number of heat-resistant steel pipes must meet a certain number, and the aging range of the pipe samples must include various aging levels, such as unaged, slightly aged, moderately aged, and severely aged, and this application does not impose specific restrictions. The certain number can be set by those skilled in the art based on actual circumstances and is not specifically limited by this application.

[0039] Furthermore, the embodiment of the present application can process the tube sample, and then make each tube into a metallographic analysis sample and a corresponding ultrasonic detection sample, wherein the length of the metallographic analysis sample meets the needs of metallographic analysis, and the length of the ultrasonic detection sample meets the needs of ultrasonic detection. The specific setting can be made by technicians in this field according to actual conditions, and this application does not impose any specific restrictions.

[0040] Illustratively, the embodiments of the present application can be based on heat-resistant steel pipes of relevant specifications and steel grades, and according to the appearance inspection and expansion measurement results of the pipe samples, pipe samples that can represent the unaged, slightly aged, moderately aged and severely aged states can be selected. On the basis of meeting the representativeness, as few pipe samples as possible are cut, and the length of the pipe samples cut is about 500 mm; the pipe samples are processed, and 20 mm to 30 mm are cut from each pipe sample to make them into metallographic analysis samples. The remaining 470 mm to 480 mm long pipe sections are used as ultrasonic detection samples, and identification marks are made on each sample.

[0041] In step S102 , a metallographic analysis is performed on the metallographic analysis sample to determine the aging level of the metallographic analysis sample.

[0042] During the actual implementation process, the embodiment of the present application can perform metallographic analysis on the metallographic analysis sample, determine the aging level, and make marks corresponding to the ultrasonic detection sample, and then measure the ultrasonic transmission characteristics of the ultrasonic detection sample to obtain the corresponding ultrasonic acoustic performance parameters.

[0043] For example, the embodiment of the present application can perform metallographic analysis on the metallographic analysis sample to verify the aging level of the metallographic structure. Among them, the embodiment of the present application can divide the material aging level into 1 to 5 levels according to the metallographic analysis standard. It can be understood that in the embodiment of the present application, levels 1 and 2 are not aged or slightly aged, which does not affect its usability; levels 3 and 4 are moderately aged; level 5 is severely aged and there is a greater risk. Pipes with an aging level of 5 are generally replaced, otherwise risk protection and operation supervision should be done well. Therefore, if a sample with aging level 5 cannot be obtained, at least a sample with aging level 4 should be available, and the test value of the sample with aging level 5 is defined based on its test data.

[0044] Furthermore, the embodiment of the present application performs metallographic analysis on the metallographic analysis samples. For example, the non-aged or slightly aged samples are rated as level 2, the moderately aged samples are rated as level 3, and the severely aged samples are rated as level 5. The ultrasonic transmission characteristics of their respective corresponding ultrasonic detection samples can be measured. After the measurement is completed, data statistics are performed to obtain the corresponding ultrasonic acoustic performance parameters, providing basic data for subsequent engineering applications.

[0045] In step S103 , ultrasonic testing is performed on the ultrasonic testing sample to obtain ultrasonic acoustic performance parameters of the ultrasonic testing sample.

[0046] As a possible implementation method, the embodiment of the present application can perform ultrasonic testing on the ultrasonic testing sample, and then obtain corresponding ultrasonic acoustic performance parameters, such as ultrasonic sound pressure data and ultrasonic sound velocity data.

[0047] Optionally, in one embodiment of the present application, before performing ultrasonic testing on the ultrasonic test sample, it also includes: testing the refraction angle or K value of the selected sensor; measuring the incident point position of the sensor on the standard test block, and marking the injection point position on the sensor; making an arc surface of the sensor detection surface according to the outer cylindrical surface of the pipe, ensuring that the detection surface is consistent with the outer cylindrical surface of the pipe being detected, and ensuring the directionality of the sensor's sound beam; making a clamping device for the sensor to ensure that the sensor fits the pipe, and the two sensors used in series move synchronously and stably, and maintain a constant pressure between the pipe to ensure the accuracy of the test results; and designing the sensor spacing to be flexibly adjusted.

[0048] It can be understood that in the embodiments of the present application, the refraction angle or K value of the sensor is an important process parameter of ultrasonic detection, which greatly affects the detection reliability; and the position of the incident point of the sensor is also an important factor affecting the detection accuracy. Therefore, accurately testing the refraction angle and incident point position of the sensor is an important link to ensure the accuracy of the detection results. The aging of steel has a weak effect on the propagation performance of ultrasonic waves. If the measurement deviation of the detection system is too large, it will directly affect the measurement results.

[0049] In some embodiments, the embodiments of the present application can mark the sensor by testing the refraction angle or K value of the selected sensor and measuring the incident point position of the sensor on a standard test block, and then making the arc surface of the sensor detection surface according to the outer cylindrical surface of the pipe to ensure that the detection surface is well matched with the outer cylindrical surface of the pipe being detected, and the sound beam directionality of the sensor is good. The detection surface of the sensor should ensure the regularity of the cylindrical shape of the arc surface and ensure that the axis of the sound beam can basically be in the same plane as the axis of the pipe, that is, to ensure that the sound waves emitted by the sensor that emits sound waves can be effectively received by the sensor that receives sound waves, that is, the sound beam directionality of the sensor meets the needs.

[0050] Furthermore, embodiments of the present application can fabricate a sensor clamping device to ensure good adhesion between the sensor and the tube. Two sensors used in tandem can move synchronously and stably, maintaining constant pressure against the tube to ensure accurate test results. The sensor spacing can be flexibly adjusted. Testing can be performed using original spare tube samples, and test data can be screened to determine the optimal sensor spacing. The relevant process conditions can be set by those skilled in the art based on actual conditions and are not specifically limited by this application.

[0051] Optionally, in one embodiment of the present application, ultrasonic testing is performed on an ultrasonic testing sample, including: determining an ultrasonic frequency that meets preset working conditions based on the ultrasonic testing sample; selecting an ultrasonic instrument that can operate within the frequency range based on the ultrasonic frequency; determining a coupling agent material and / or scanning method based on the ultrasonic frequency, ultrasonic instrument, and sensor type and parameters; and performing ultrasonic testing based on the operating frequency, coupling material, and / or scanning method.

[0052] In some embodiments, when performing ultrasonic testing, the process is as follows: Figure 2 As shown, the main contents are:

[0053] Step S201: Obtain instrument information of a corresponding ultrasonic testing instrument.

[0054] Among them, the embodiment of the present application can determine the corresponding ultrasonic detection instrument when performing ultrasonic detection, and verify whether the performance of the current ultrasonic detection instrument meets the needs of the detection work. Before computer technology was applied to ultrasonic detection, ultrasonic detection instruments were "analog machines". The signals detected by the system were all transmitted from the sensor to the display screen, and there was no signal loss; while the "digital machine" using computer technology has a certain sampling rate, that is, the instrument records or extracts the signal sent back by the sensor once at a certain interval, and the signal that is not recorded or extracted is lost. The problem of sampling rate mainly involves the computing power of the chip used in the ultrasonic detection instrument and the storage capacity of the storage component. A high sampling rate means less signal loss, which is beneficial to the detection results, but the instrument has a large amount of computing and storage capacity, and the detection speed will be relatively slow. Although the "digital machine" has a development history of nearly 30 years, its performance still needs to be verified, otherwise the old "analog machine" must be used.

[0055] Step S202: Determine the operating frequency of the ultrasonic detection instrument.

[0056] The present embodiment of the present invention screens and determines the operating frequency of an ultrasonic testing instrument that meets certain operating conditions based on test results of samples of different steel grades and different aging levels. The operating frequency of an ultrasonic testing instrument is the primary parameter affecting the ultrasonic attenuation coefficient. Furthermore, specific operating conditions can be set by those skilled in the art based on actual circumstances and are not specifically limited in this application.

[0057] It should be noted that the goal of the embodiments of this application is to achieve nondestructive testing of in-service components, so testing the outer wall of the pipe is more reasonable. Shear wave sensors are used for testing thicker pipes, while shear wave sensors, plate wave sensors, or surface wave sensors are used for testing thinner pipes. A combination of shear wave sensors, plate wave sensors, or surface wave sensors can also be used based on the thickness of the pipe wall. Furthermore, the embodiments of this application can select the sensor chip size, angle, and other sensor parameters based on test results.

[0058] For example, in the embodiment of the present application, an ultrasonic testing instrument may be selected to determine that the operating frequency range is between 1 MHz and 20 MHz, and to confirm that its vertical linearity and horizontal linearity meet the standards.

[0059] Furthermore, the embodiments of the present application can respectively select shear wave sensors and plate wave sensors, and use original spare tube samples according to low frequency (1MHz~2.5MHz), medium frequency (5MHz) and high frequency (10MHz~15MHz) to test and determine the available working frequency and corresponding frequency sensors with high detection sensitivity.

[0060] Step S203: Determine the scanning method of ultrasonic testing.

[0061] Among them, since the embodiment of the present application does not detect defects and reflectors, it can achieve non-destructive testing and evaluation of heat-resistant steel components without sampling. It can adopt a serial scanning method of "one transmit and one receive" of two sensors to detect and obtain data on the outer surface of the pipe.

[0062] Step S204: Determine detection information of the ultrasonic detection instrument.

[0063] The present application also addresses the selection of the distance between sensors and the design of a sensor clamping device. If the distance between the two sensors is too small, the errors in the sound velocity and sound pressure attenuation of the tested material will be large, resulting in poor detection reliability. If the distance between the sensors is too large, the error in the sound velocity of the tested material will be small, but the sound pressure attenuation will be excessive, which will also increase the measurement error. Therefore, the spacing between the tandem sensors should be determined based on test results, pipes of different specifications, and materials. A sensor clamping device that allows for flexible adjustment of the sensor spacing should be designed based on the sensor type and the spacing between the tandem sensors.

[0064] Step S205: Determine the coupling agent material.

[0065] Among them, when obtaining the coupling agent material, the embodiment of the present application can reasonably select the coupling agent according to the operating frequency of the ultrasonic detection instrument, the type of sensor, etc., to ensure good coupling between the sensor and the pipe and the effectiveness of ultrasonic transmission; among them, when detecting austenitic steel, the embodiment of the present application selects a coupling agent that does not contain chloride ions.

[0066] Optionally, in one embodiment of the present application, ultrasonic testing is performed on the ultrasonic testing sample, including: cleaning and polishing the surface of the ultrasonic testing sample to meet the needs of ultrasonic testing; selecting the type and parameters of the sensor according to the outer diameter parameters and wall thickness parameters of the ultrasonic testing sample, and setting the distance between the two sensors.

[0067] As a possible implementation method, before testing, the embodiment of the present application should clean and polish the surface of the sample to remove debris, rust and oxide layer on the surface of the sample to ensure that the sensor can effectively fit the test sample and ensure the effectiveness of ultrasonic transmission.

[0068] Among them, the embodiment of the present application can select the type and parameters of the sensor and set the distance between the two sensors based on the outer diameter parameters and wall thickness parameters of the ultrasonic detection sample.

[0069] In addition, in order to ensure stable contact between the sensor and the sample and avoid changes in the sensor's pressing force on the sample surface causing excessive errors in the test sound wave attenuation, that is, affecting the sound velocity measurement results, the embodiment of the present application should try to ensure that the pressing force is constant.

[0070] Optionally, in one embodiment of the present application, ultrasonic testing is performed on the ultrasonic testing sample to obtain the ultrasonic acoustic performance parameters of the ultrasonic testing sample, including: obtaining the steel grade information and specification information corresponding to the heat-resistant steel pipe sample; obtaining the original spare pipe sample and the pipe samples with different aging levels through the steel grade information; performing ultrasonic testing on the original spare pipe sample to obtain the ultrasonic acoustic performance parameters of the unaged heat-resistant steel pipe sample; performing ultrasonic testing on the pipe samples with different aging levels to obtain the ultrasonic acoustic performance parameters corresponding to the heat-resistant steel pipe samples with different aging levels.

[0071] In some embodiments, the embodiments of the present application can obtain original spare pipe samples and pipe samples with different aging levels based on the steel grade information and specification information corresponding to the heat-resistant steel pipe samples, and perform ultrasonic testing on the original spare pipe samples and pipe samples with different aging levels respectively, so as to obtain the ultrasonic acoustic performance parameters of the unaged heat-resistant steel pipe samples and the ultrasonic acoustic performance parameters corresponding to the heat-resistant steel pipe samples with different aging levels.

[0072] In step S104, based on the aging level of the metallographic analysis sample and the ultrasonic acoustic performance parameters of the ultrasonic detection sample, a database of the relationship between the aging level of the heat-resistant steel pipe sample and the corresponding ultrasonic acoustic performance parameters is established.

[0073] In some embodiments, the present application can analyze and demonstrate the impact of the structural properties of different heat-resistant steel materials on ultrasonic propagation characteristics, including the impact of material structural changes on sound pressure data during ultrasonic transmission and the impact of material property changes on ultrasonic propagation speed data. Furthermore, the present application can generate a database based on the relationship between different aging levels and ultrasonic acoustic performance parameters. The main contents are:

[0074] (1) The influence of creep aging of heat-resistant steel on the propagation velocity of ultrasonic waves in it.

[0075] In the embodiments of the present application, the sound velocity of a solid medium is related to the density and elastic modulus of the medium. Different media have different sound velocities. In an infinite solid medium (with a size much larger than the wavelength), the expression for the shear wave sound velocity is:

[0076]

[0077] Among them, E is the Young's modulus of elasticity of the medium; G is the shear elastic modulus of the medium; ρ is the density of the medium; σ is the Poisson's ratio of the medium. The Poisson's ratio of all solid media is between 0 and 0.5.

[0078] Furthermore, in the embodiments of this application, elastic modulus can be understood as the proportional relationship or proportional coefficient between stress and strain in a material during its elastic deformation phase. It is a physical quantity related to the material's strength and elastic-plastic properties. As heat-resistant steel ages, its elastic modulus changes due to creep, and its density also changes due to creep expansion. Therefore, creep aging can affect the speed of ultrasound waves within it.

[0079] (2) The influence of creep aging of heat-resistant steel on the sound pressure of ultrasonic waves propagating in it.

[0080] In the embodiments of this application, as ultrasound propagates through a medium, its energy gradually weakens (ultrasonic attenuation) and its sound pressure decreases with increasing distance. Causes of ultrasonic attenuation can include beam diffusion, grain scattering, and medium absorption, as well as dislocations, domain walls, and residual stress. The specific attenuation can be determined by those skilled in the art based on actual conditions and is not a limitation of this application.

[0081] Furthermore, the embodiment of the present application also considers scattering attenuation and absorption attenuation to calculate the medium attenuation. The medium attenuation coefficient is equal to the sum of the scattering attenuation coefficient and the absorption attenuation coefficient, and its expression can be, but is not limited to,:

[0082] α=α s +α a ,

[0083] Among them, α is the medium attenuation coefficient, α s is the scattering attenuation coefficient; αa is the absorption attenuation coefficient.

[0084] It should be noted that in the embodiments of the present application, scattering attenuation is closely related to the grain size of the material. When the grains are coarse, the scattering attenuation is severe; absorption attenuation is the attenuation caused by internal friction and heat conduction between material particles; after aging of heat-resistant steel, its grain size, internal friction between particles and heat conduction characteristics will change, and its dislocations, magnetic domain walls and residual stresses will change, so its attenuation coefficient will also change significantly.

[0085] (3) Measurement of sound velocity of heat-resistant steel after creep aging.

[0086] Among them, if the embodiment of the present application adopts a sampling measurement method, ultrasonic longitudinal waves can be used to measure the sound velocity of the sample. As shown in Figure 3(a), a single probe can be used to measure using the single reflection method; as shown in Figure 3(b), a dual probe can be used to measure using the serial scanning method.

[0087] Furthermore, in the embodiment of the present application, if the method of FIG. 3( a ) is followed, the instrument system transmits an ultrasonic sound beam from the sensor at end A of the sample, which reaches end B and is reflected by the end face and then returns to the sensor. The entire distance is S = 2L. Assuming that the time taken is 2t, the expression for the propagation speed of the ultrasonic wave in the sample can be, but is not limited to,:

[0088]

[0089] Where C is the speed of ultrasonic wave propagation in the sample; L is the length of the sample; and t is the time required for ultrasonic wave to travel from end A to end B of the sample.

[0090] In addition, in the embodiment of the present application, if the method of FIG. 3( b ) is followed, the sensor at the end A of the sample transmits ultrasonic waves that are received by the sensor at the end B. The entire distance is S=L. Assuming that the time taken is t, the expression for the measured sound speed is:

[0091]

[0092] It should be noted that if the accuracy of the test is considered in the embodiment of the present application, the distance from the sensor chip to the detection surface, which is the so-called "zero point" problem, must also be considered, that is, the "zero point" of the instrument system must be correctly adjusted.

[0093] However, when testing power equipment, it is natural to use non-destructive methods to measure the ultrasonic sound velocity of various metal parts. For power pipelines, the most suitable method to measure the ultrasonic sound velocity without sampling is to use shear waves or plate waves (thin-walled parts) and serial scanning tests. The specific operation method is as follows: Figure 4The distance of ultrasonic wave propagation should be calculated based on the distance L between the incident points of the two sensors and the refraction angle β or K value of the sensor, that is, S = K × L = tanβ × L, where β is the refraction angle of the sensor.

[0094] (4) Measurement of sound pressure after creep aging of heat-resistant steel.

[0095] Among them, in the embodiment of the present application, the ultrasonic detection instrument tests the sound pressure value of the ultrasonic beam. Therefore, the attenuation of the ultrasonic beam energy is usually determined and often characterized by sound pressure attenuation.

[0096] The attenuation of ultrasonic sound pressure is typically determined by the shape of the reflector being detected. The serial scanning method does not involve the specific reflectors detected by the direct beam method. Therefore, the present embodiment can be used to obtain relevant reference data through experimental testing on selected samples. This method does not consider reflection losses from the pipe wall, and can also avoid deviations or errors caused by theoretical calculations, making the data more reliable.

[0097] In step S105, actual engineering inspection is carried out to obtain ultrasonic acoustic performance parameters of the heat-resistant steel pipes of the thermal equipment inspected in the actual project, and the aging level of the inspected heat-resistant steel pipes is determined by searching the database. The safety and reliability of the heat-resistant steel pipes inspected in the actual project are determined based on the aging level of the inspected heat-resistant steel pipes, so as to determine which heat-resistant steel pipes in the thermal equipment can continue to be used and / or which heat-resistant steel pipes are severely aged and need to be replaced.

[0098] In some embodiments, the embodiments of the present application can determine the aging level of the actual heat-resistant steel pipe samples using a database based on the ultrasonic acoustic performance parameters of the heat-resistant steel pipes of the thermal equipment being tested when conducting actual engineering inspections, and then determine the safety and reliability of the heat-resistant steel pipes of the thermal equipment being tested, and judge which steel pipes in the thermal equipment can continue to be used and which need to be replaced due to severe aging.

[0099] It can be understood that when determining the aging level of the heat-resistant steel pipe of the thermal equipment being tested, in order to make the test results more reasonable, the embodiment of the present application can combine the database of the relationship between the aging level obtained by metallographic analysis and the ultrasonic acoustic performance parameters corresponding to ultrasonic testing.

[0100] The embodiment of the present application finds relevant regularities through statistical analysis of the database, and uses "extrapolation" or theoretical analysis methods to correct the data. When testing pipes of different specifications of the same steel material, it can be used as basic data for determining the basis or reference of the test results, thereby avoiding the problem of obtaining too few samples and insufficient representativeness of the test data.

[0101] Optionally, in one embodiment of the present application, actual engineering inspections are carried out to obtain ultrasonic acoustic performance parameters of the heat-resistant steel pipes of the thermal equipment inspected in the actual engineering, the aging level of the inspected heat-resistant steel pipes is determined by searching a database, and the safety and reliability of the heat-resistant steel pipes inspected in the actual engineering are determined based on the aging level of the inspected heat-resistant steel pipes, so as to determine which heat-resistant steel pipes in the thermal equipment can continue to be used and / or which heat-resistant steel pipes are severely aged and need to be replaced, including: carrying out actual engineering inspections, performing ultrasonic inspections on the heat-resistant steel pipes of the thermal equipment, and obtaining ultrasonic acoustic performance parameters of the heat-resistant steel pipes of the thermal equipment inspected; determining the aging level of the heat-resistant steel pipes of the thermal equipment inspected by searching a database based on the ultrasonic acoustic performance parameters of the heat-resistant steel pipes of the thermal equipment inspected; determining the safety and reliability of the heat-resistant steel pipes of the thermal equipment inspected based on the aging level of the heat-resistant steel pipes of the thermal equipment inspected, so as to determine which heat-resistant steel pipes in the thermal equipment inspected can continue to be used and / or which are severely aged and need to be replaced.

[0102] As a possible implementation method, the embodiment of the present application can perform ultrasonic testing on the heat-resistant steel pipes of the thermal equipment being tested during actual engineering testing, thereby obtaining corresponding ultrasonic acoustic performance parameters, and then determining the aging level of the heat-resistant steel pipes of the thermal equipment being tested through database search, thereby determining the usable and replaceable steel pipes in the thermal equipment.

[0103] The working principle of the method for rapid detection and evaluation of aging of heat-resistant steel proposed in the embodiments of the present application is introduced below in combination with multiple embodiments.

[0104] in, Figure 5 The present invention is a flowchart of the working principle of the method for rapid detection and evaluation of aging of heat-resistant steel provided according to one embodiment of the present application.

[0105] Example 1: A tandem shear wave sensor is used to detect and evaluate the aging level of the high-temperature superheater tubes of boiler A.

[0106] Step S501: Prepare a sample.

[0107] In this embodiment of the present application, representative tubes of Boiler A's high-temperature superheater are selected based on a comprehensive visual inspection and expansion measurement. Samples of approximately 500 mm in length are then cut from these tubes. For example, a 500 mm section is taken from each of the tubes that appear to be unaged or mildly aged, as well as moderately aged and severely aged, as indicated by both appearance and expansion measurement. Samples of 20 to 30 mm in length are then cut from each section for metallographic analysis. The remaining 470 to 480 mm section is then used as an ultrasonic testing sample. Identification marks are then placed on each sample.

[0108] Step S502: Determine the aging level.

[0109] Among them, the embodiment of the present application can perform metallographic analysis on the metallographic analysis sample to verify the aging level of the metallographic structure.

[0110] Step S503: Perform ultrasonic testing.

[0111] Combine Figure 2 As shown, the embodiment of the present application can polish and clean the ultrasonic detection sample to remove the ash and oxide layer on the surface that affects the transmission of ultrasonic waves, revealing the metallic luster.

[0112] If it is the first detection, the embodiment of the present application can select an ultrasonic detection instrument with an operating frequency range of 0MHz to 20MHz, select shear wave ultrasonic sensors with three frequencies of 5MHz, 10MHz and 15MHz, select sensor K values ​​of 1, 1.5 and 2 respectively, and test the incident point of the sensor on a standard test block.

[0113] Furthermore, embodiments of the present application can fabricate a clamping device that can flexibly adjust the spacing between the tandem sensors, ensuring that the pressure applied by the sensors to the pipe remains constant during testing. The spacing between the tandem sensors can be, but is not limited to, 100 mm, 200 mm, and 300 mm, and this application does not impose any specific restrictions.

[0114] Furthermore, the embodiments of the present application can be tested on ultrasonic testing specimens. Assume that two sensors are numbered A and B respectively. Let sensor A be fixed on the clamping device, and sensor B can be flexibly moved to adjust the distance between it and sensor A. First, test with a distance of 100 mm between the two sensors. After applying coupling agent on the pipe detection area, place the two sensors on the pipe, move sensor B back and forth, let the amplitude on the instrument display reach the maximum value, and record the distance between the sensors and the amplitude value displayed on the instrument at this time. Test each item according to the aforementioned sensor parameters, and determine the optimal combination process with high detection sensitivity and strong data contrast based on statistical data analysis, so as to obtain good detection results in practical applications.

[0115] In addition, in the embodiment of the present application, the arc surface of the sensor detection surface is made according to the outer cylindrical surface of the pipe to ensure good directivity of the sensor's sound beam; the detection area of ​​the pipe is polished and cleaned; a coupling agent is selected; the instrument system is calibrated during the detection; and relevant detection records are kept.

[0116] Step S504: Determine the aging level of the heat-resistant steel pipe of the thermal equipment being tested.

[0117] Among them, the embodiment of the present application can determine the aging level of the detected heat-resistant steel pipe of the thermal equipment through the database based on the ultrasonic acoustic performance parameters of the detected heat-resistant steel pipe of the thermal equipment.

[0118] Example 2: Using a serial plate wave sensor to detect and evaluate the aging level of the high-temperature reheater tubes of boiler B.

[0119] It can be understood that in the embodiment of the present application, the ultrasonic plate wave is easier to propagate in thin-walled tubes, and there is no need to consider the influence of wall reflection. Therefore, it is more effective in detecting and evaluating the aging level of thin-walled small-diameter tubes such as high-temperature reheaters of thermal power boilers.

[0120] Step S501: Prepare a sample.

[0121] In this embodiment, a comprehensive visual inspection and expansion measurement of the high-temperature reheater of boiler B can be performed. Representative tubes are selected and pipe samples are cut approximately 500 mm in length. For example, a 500 mm section is taken from each of the tubes that appear to be unaged or slightly aged, moderately aged, and severely aged, as determined by both appearance and expansion measurement. From this section, 20 mm to 30 mm sections are cut as metallographic analysis samples. The remaining 470 mm to 480 mm section is used as ultrasonic testing sample. Identification marks are then made on each sample.

[0122] Step S502: Determine the aging level.

[0123] Among them, the embodiment of the present application can perform metallographic analysis on the metallographic analysis sample to verify the aging level of the metallographic structure.

[0124] Step S503: Perform ultrasonic testing.

[0125] Among them, the embodiment of the present application can polish and clean the ultrasonic detection sample to remove the ash and oxide layer on the surface that affects the transmission of ultrasonic waves, revealing the metallic luster.

[0126] If it is the first test, the embodiment of the present application can select an ultrasonic detection instrument with an operating frequency range of 0MHz to 20MHz, select plate wave ultrasonic sensors with three frequencies of 5MHz, 10MHz and 15MHz, and test the incident point of the sensor on a standard test block.

[0127] Furthermore, embodiments of the present application can fabricate a clamping device that can flexibly adjust the spacing between the tandem sensors, ensuring that the pressure applied by the sensors to the pipe remains constant during testing. The spacing between the tandem sensors can be, but is not limited to, 100 mm, 200 mm, and 300 mm, and this application does not impose any specific restrictions.

[0128] Furthermore, the embodiments of the present application can be tested on ultrasonic specimens. Assume that two sensors are numbered A and B respectively. Let sensor A be fixed on the clamping device, and sensor B can be flexibly moved to adjust the distance between it and sensor A. First, test with a distance of 100 mm between the two sensors. After applying coupling agent on the pipe detection area, place the two sensors on the pipe, move sensor B back and forth, and let the amplitude on the instrument display reach the maximum value. Record the distance between the sensors and the amplitude value displayed on the instrument at this time. Test each item according to the aforementioned sensor parameters, and determine the optimal combination process with high detection sensitivity and strong data contrast based on statistical data analysis, so as to obtain good detection results in practical applications.

[0129] In addition, in the embodiment of the present application, the arc surface of the sensor detection surface is made according to the outer cylindrical surface of the pipe to ensure good directivity of the sensor's sound beam; the detection area of ​​the pipe is polished and cleaned; a coupling agent is selected; the instrument system is calibrated during the detection; and relevant detection records are kept.

[0130] It should be noted that in the embodiment of the present application, since the specifications and steel types of the actual tested pipes are exactly the same as those of the samples in Example 1, the aging level of the material can be determined directly based on the comparison of the test results with the aforementioned experimental results; if the ultrasonic test samples are insufficient and cannot fully cover the aging levels of 1 to 5, the relevant methods in Example 1 or Example 2 can be referred to.

[0131] Step S504: Determine the aging level of the heat-resistant steel pipe of the thermal equipment being tested.

[0132] Among them, the embodiment of the present application can determine the aging level of the detected heat-resistant steel pipe of the thermal equipment through the database based on the ultrasonic acoustic performance parameters of the detected heat-resistant steel pipe of the thermal equipment.

[0133] Example 3: Using an ultrasonic serial scanning method to detect and evaluate the aging level of large-diameter heat-resistant steel pipes or components.

[0134] In summary, the embodiments of the present application can determine the coupling mode between the sensor and the sample according to the surface condition of the sample; determine the waveform to be adopted according to the structural shape of the sample; determine the detection method to be adopted according to the structural shape of the sample; for other issues, refer to Embodiment 1 and Embodiment 2.

[0135] According to the method for rapid detection and evaluation of heat-resistant steel aging proposed in the embodiment of the present application, based on the information of the steel pipes used in the thermal equipment to be tested, heat-resistant steel pipe samples of relevant specifications and steel grades can be collected, and corresponding metallographic analysis samples and ultrasonic testing samples can be made. The aging level of the metallographic analysis sample and the ultrasonic acoustic performance parameters of the ultrasonic testing sample are determined by metallographic analysis and ultrasonic testing, respectively. Then, a database of the relationship between the aging level of the heat-resistant steel pipe samples and the corresponding ultrasonic acoustic performance parameters is established. When carrying out actual engineering testing, the corresponding aging level is determined by searching the database based on the ultrasonic acoustic performance parameters of the heat-resistant steel pipes of the thermal equipment to be tested, and the safety and reliability of the heat-resistant steel pipes of the thermal equipment to be tested are determined. Then, which heat-resistant steel pipes of the thermal equipment can continue to be used and / or which heat-resistant steel pipes need to be replaced due to severe aging, thereby improving the safety and reliability of the thermal equipment and reducing unplanned downtime losses. This solves the problem in the related art that the metallographic analysis method is cumbersome and time-consuming, and is prone to health hazards during sample preparation and polishing; and other non-metallographic analysis methods have detection effects and reliability that need to be verified.

Claims

1. A method for rapid detection and evaluation of heat-resistant steel aging, characterized in that: The following steps are involved: Based on the information of the steel pipes used in the thermal equipment to be tested, heat-resistant steel pipe samples of relevant specifications and steel grades are collected, and the heat-resistant steel pipe samples are made into metallographic analysis samples and corresponding ultrasonic testing samples; Performing metallographic analysis on the metallographic analysis sample to determine the aging level of the metallographic analysis sample; Performing ultrasonic testing on the ultrasonic testing sample to obtain ultrasonic acoustic performance parameters of the ultrasonic testing sample; Based on the aging level of the metallographic analysis sample and the ultrasonic acoustic performance parameters of the ultrasonic detection sample, a database of the relationship between the aging level of the heat-resistant steel pipe sample and the corresponding ultrasonic acoustic performance parameters is established; Conduct actual engineering inspections to obtain ultrasonic acoustic performance parameters of heat-resistant steel pipes of thermal equipment inspected in the actual engineering, determine the aging level of the inspected heat-resistant steel pipes by searching the database, and determine the safety and reliability of the inspected heat-resistant steel pipes in the actual engineering based on the aging level of the inspected heat-resistant steel pipes, so as to determine which heat-resistant steel pipes in the thermal equipment can continue to be used and / or which heat-resistant steel pipes are severely aged and need to be replaced.

2. The method according to claim 1, characterized in that The method includes collecting heat-resistant steel pipe samples of relevant specifications and steel types based on the information of the steel pipes used in the thermal equipment to be tested, and making the heat-resistant steel pipe samples into metallographic analysis samples and corresponding ultrasonic testing samples, including: Based on the heat-resistant steel pipes of the relevant specifications and steel grades, a preset number of pipe samples are prepared, wherein the specifications and steel grades of the pipe samples are consistent with the pipes of thermal equipment, and the aging range of the pipe samples includes various aging levels; The tube samples are processed, and each tube is made into a metallographic analysis sample and a corresponding ultrasonic detection sample, wherein the length of the ultrasonic detection sample meets the requirements of ultrasonic detection.

3. The method according to claim 1, characterized in that The ultrasonic testing of the ultrasonic testing sample comprises: Cleaning and polishing the surface of the ultrasonic testing sample to meet the needs of ultrasonic testing; According to the outer diameter parameters and wall thickness parameters of the ultrasonic testing sample, the type and parameters of the sensor are selected and the distance between the two sensors is set.

4. The method according to claim 1, wherein The ultrasonic testing of the ultrasonic testing sample comprises: Determining an ultrasonic frequency that meets preset working conditions based on the ultrasonic testing sample; Based on the ultrasonic frequency, selecting an ultrasonic instrument that can operate within the frequency range; Determining the coupling agent material and / or scanning method according to the ultrasonic frequency, the ultrasonic instrument, and the type and parameters of the sensor; The ultrasonic detection is performed based on the operating frequency, the coupling material and / or the scanning method.

5. The method according to claim 1, wherein Before performing ultrasonic testing on the ultrasonic testing sample, the method further includes: Test the refraction angle or K value of the selected sensor; Measuring the incident point position of the sensor on a standard test block, and marking the incident point position on the sensor; The arc surface of the sensor detection surface is made according to the outer cylindrical surface of the pipe, ensuring that the detection surface is consistent with the outer cylindrical surface of the pipe being detected and ensuring the directivity of the sensor's sound beam; Make a clamping device for the sensor to ensure that the sensor fits the pipe, and the two sensors used in series move synchronously and stably, and maintain constant pressure between them and the pipe to ensure the accuracy of the detection results; The sensor spacing is designed to be flexibly adjusted.

6. The method according to claim 1, wherein The ultrasonic testing of the ultrasonic testing sample to obtain ultrasonic acoustic performance parameters of the ultrasonic testing sample includes: Obtaining steel grade information and specification information corresponding to the heat-resistant steel pipe sample; Obtaining original spare pipe samples and pipe samples with different aging levels through the steel grade information; Performing ultrasonic testing on the original spare pipe sample to obtain ultrasonic acoustic performance parameters of the unaged heat-resistant steel pipe sample; Ultrasonic testing is performed on the pipe samples of different aging levels to obtain ultrasonic acoustic performance parameters corresponding to the heat-resistant steel pipe samples of different aging levels.

7. The method according to claim 1, characterized in that The actual engineering inspection is carried out to obtain ultrasonic acoustic performance parameters of the heat-resistant steel pipes of the thermal equipment inspected in the actual engineering, the aging level of the inspected heat-resistant steel pipes is determined by searching the database, and the safety and reliability of the inspected heat-resistant steel pipes in the actual engineering are determined based on the aging level of the inspected heat-resistant steel pipes, so as to determine which heat-resistant steel pipes in the thermal equipment can continue to be used and / or which heat-resistant steel pipes are severely aged and need to be replaced, including: Carry out actual engineering testing, perform ultrasonic testing on the heat-resistant steel pipes of the thermal equipment, and obtain ultrasonic acoustic performance parameters of the tested heat-resistant steel pipes of the thermal equipment; Determining the aging level of the heat-resistant steel pipe of the thermal equipment under test by searching the database according to the ultrasonic acoustic performance parameters of the heat-resistant steel pipe of the thermal equipment under test; The safety and reliability of the heat-resistant steel pipes of the thermal equipment under test are determined according to their aging levels, so as to determine which heat-resistant steel pipes in the thermal equipment under test can continue to be used and / or which ones are severely aged and need to be replaced.

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