Overtemperature monitoring and early warning method and system for high-temperature heating surface pipe of boiler
By deploying a sensor array and using finite element thermal stress fitting on the high-temperature heating surface tubes of the boiler, the problem of the inability to identify overheated areas in real time in traditional boiler monitoring technology has been solved, realizing real-time safety monitoring and fault early warning of the boiler, and improving the safety and stability of equipment operation.
Patent Information
- Application Number
- CN202511540938.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-27
- Publication Date
- 2025-12-16
AI Technical Summary
Traditional boiler monitoring technology cannot capture the dynamic temperature changes of the boiler's high-temperature heating surface tubes in real time, which makes it impossible to identify potential overheating areas in a timely manner, increasing the risk of equipment operation and failure rate.
By deploying temperature and displacement sensor arrays on the high-temperature heating surface tubes of the boiler, and combining material property information and real-time operating parameters, finite element thermal stress fitting is performed to locate the over-temperature and stress concentration areas, and output real-time level warnings.
It enables real-time temperature monitoring and stress analysis of the high-temperature heating surface tubes of the boiler, improving monitoring coverage and accuracy, timely identification of overheating risks, reducing the occurrence of faults, and ensuring the safe operation of the boiler.
Smart Images
Figure CN121139944A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of overheat monitoring technology, and in particular to a method and system for monitoring and early warning of overheating of high-temperature heating surface tubes in boilers. Background Technology
[0002] Traditional boiler monitoring technologies typically employ static temperature and pressure monitoring, relying on sensors at fixed locations for periodic data collection. These technologies can only reflect temperature and pressure data at fixed measurement points and cannot capture the temperature distribution and dynamic changes between tubes. They also lack comprehensive assessment methods for the dynamic changes of boilers under different operating conditions.
[0003] However, under conditions such as rapid load changes and deep peak shaving, the temperature of the boiler's heating surface and tubes fluctuates greatly. In such cases, traditional methods cannot fully consider the impact of these dynamic changes on boiler components, nor can they effectively combine dynamic data and complex thermal stress changes under different operating conditions. This results in the inability to detect potential overheating areas of the boiler's high-temperature heating surface tubes in real time, which in turn leads to the inability to take timely measures, increasing the operational risks and failure rate of the equipment. Summary of the Invention
[0004] The purpose of this application is to provide a method and system for monitoring and early warning of overheating of boiler high-temperature heating surface tubes, in order to solve the technical problem that the existing technology lacks real-time dynamic feedback on the boiler status, cannot identify potential overheating areas of boiler high-temperature heating surface tubes in a timely manner, and increases the operational risk of the equipment.
[0005] Firstly, this application provides a method for monitoring and early warning of overheating of high-temperature heating surface tubes in a boiler, comprising: Step S1: Deploy measurement points in the easily overheated zone of the boiler's high-temperature heating surface tubes to obtain a temperature sensing array; Step S2: Pre-deploy displacement sensing arrays at key structural locations in the boiler furnace; Step S3: Interact to obtain the material property information of the high-temperature heating surface tube of the boiler, and aggregate the material design information based on the material property information to obtain the material design safety threshold. Step S4: In real time, compare whether the real-time wall temperature array returned by the temperature sensing array meets the material design safety threshold. If the conditions are not met, the real-time overheating area is located based on the spatial projection of the real-time wall temperature array onto the high-temperature heating surface tubes of the boiler. Step S5: Interact with the boiler to obtain real-time operating parameters, and combine the expansion data returned by the real-time wall temperature array and the displacement sensing array to perform finite element thermal stress fitting to locate the stress concentration area. Step S6: Based on the spatial correlation characteristics between the real-time over-temperature region and the stress concentration region, output a real-time level warning.
[0006] Furthermore, in step S3, the material property information of the boiler high-temperature heating surface tube is obtained interactively through local retrieval, and the material property information includes the material grade, material design temperature and material alarm temperature.
[0007] Furthermore, in step S3, the method further includes: retrieving historical material degradation data from a metal monitoring database based on the material grade, and associating it with historical overheating durations. The historical material degradation data includes oxide scale thickness, hardness degradation, and wall thickness reduction. Based on the historical material degradation data and the material design temperature, the material alarm temperature is used to correct for degradation, thereby obtaining a degradation temperature correction threshold. After interactively obtaining real-time operating conditions, the degradation temperature correction threshold is modified according to the real-time operating conditions, and the material design safety threshold is output.
[0008] Furthermore, in step S4, the method for locating the real-time overheating region based on the spatial projection of the real-time wall temperature array onto the high-temperature heating surface tubes of the boiler includes: By comparing the real-time wall temperature array with the material design safety threshold at each measurement point, multiple real-time over-temperature measurement points are obtained. A 3D model of four boiler tubes covering the high-temperature heating surface tubes of the boiler is pre-constructed, and the spatial regions of the tube segments are associated in the 3D model of four boiler tubes. After projecting the multiple real-time over-temperature measurement points onto the pipe segment space region, regional correlation analysis is performed on adjacent over-temperature measurement points to output the real-time over-temperature region, which is marked with a pipe segment number and an over-temperature extreme value.
[0009] Furthermore, step S5 includes: After constructing a dynamic finite element mesh based on the 3D model of the four-tube boiler, the finite element model of the four-tube boiler is generated by loading the real-time operating parameters, which include the real-time temperature field, internal pressure load and expansion displacement constraint. The real-time wall temperature array, the real-time operating parameters, and the expansion data returned by the displacement sensing array are loaded into the four-tube finite element model of the boiler to solve for transient thermal stress distribution and output the stress concentration region.
[0010] Furthermore, step S6 includes: Spatial coordinate mapping of the real-time overheating region and the stress concentration region is performed on the 3D model of the four tubes of the boiler to obtain the spatially overlapping region. Retrieve the extreme regional temperatures of the overlapping spatial regions; The percentage of overlapping area is calculated based on the union area of the real-time overheating region and the stress concentration region and the spatially overlapping region. The real-time level warning is obtained by matching the pipe segment number identifier and the over-temperature extreme value identifier of the real-time over-temperature zone, as well as the temperature extreme value of the zone and the percentage of the overlapping area, in the warning rule base.
[0011] Furthermore, step S1 includes: Step S11: Based on the initial monitoring accuracy, locate the basic measuring points of the high-temperature heating surface tubes of the boiler to obtain the initial temperature measuring point distribution; Step S12: Locate multiple overheat-prone areas of the boiler's high-temperature heating surface tubes; Step S13: Based on the structural characteristics of the temperature-overheating regions, temperature measurement points are located in the multiple temperature-overheating regions to obtain a structurally optimized measurement point distribution. Step S14: The compensation results of the initial temperature measuring point distribution are obtained by using the structure-optimized measuring point distribution, and a temperature sensing array is deployed on the high-temperature heating surface tube of the boiler.
[0012] Furthermore, step S13 includes: Step S131: Interact to obtain the first structure ID of the boiler structure to which the first overheating zone belongs; Step S132: After extracting the first region structural features of the first region prone to overheating, use the first region structural features and the first structure ID as search conditions to search the distribution of the first working fluid uneven flow region and the distribution of the first defect region online. Step S133: After solving the union of the distribution of the first uneven flow region of the working fluid and the distribution of the first defect region, the measurement points are deployed in a coverage manner to obtain the first optimized measurement point distribution. Step S134: By analogy, temperature measuring points are located in the multiple areas prone to overheating to obtain multiple optimized measuring point distributions, which constitute the structure-optimized measuring point distribution.
[0013] Furthermore, step S133 includes: performing spatial overlap analysis on the distribution of the first uneven flow region of the working fluid and the distribution of the first defect region to determine the union region, and optimizing the arrangement of measuring points based on the range of the union region.
[0014] Secondly, this application provides a boiler high-temperature heating surface tube overheating monitoring and early warning system, characterized in that it is applied to the boiler high-temperature heating surface tube overheating monitoring and early warning method described in any one of the preceding statements. The system includes: an easy overheating measurement point deployment module, a displacement sensor array deployment module, a material design information aggregation module, a real-time wall temperature array comparison module, a real-time overheating area positioning module, a finite element thermal stress fitting module, and a real-time level early warning output module, as well as a system control module.
[0015] Compared with existing technologies, the boiler high-temperature heating surface tube over-temperature monitoring and early warning method and system provided in this application deploys easily over-temperature measuring points on the boiler high-temperature heating surface tubes to obtain a temperature sensor array. This allows for real-time acquisition of temperature data from each measuring point, improving the coverage and accuracy of boiler tube temperature monitoring and providing a reliable data foundation for subsequent over-temperature early warning. By comparing the real-time wall temperature array returned by the temperature sensor array with the design safety threshold in real time, it can promptly identify whether there is an over-temperature risk in the boiler tubes, providing a real-time temperature control feedback mechanism for safe boiler operation. If an over-temperature risk is identified, it can accurately determine the location of the over-temperature risk through spatial projection. The system identifies real-time over-temperature zones, efficiently pinpointing the specific locations of abnormal internal boiler temperatures. This provides boiler maintenance personnel with clear spatial location information, improving maintenance efficiency and enhancing boiler operational safety. Furthermore, by combining real-time operating parameters, expansion data from real-time wall temperature arrays, and displacement sensor arrays for finite element thermal stress fitting, it locates stress concentration areas. Identifying these stress concentration areas can provide early warnings of potential pipe ruptures, fatigue, and other faults, reducing the occurrence of sudden accidents. Finally, by comprehensively analyzing the spatial correlation characteristics of real-time over-temperature zones and stress concentration areas, it outputs real-time level warnings. This warning mechanism can flexibly adjust the warning level based on the current boiler operating status, the current real-time over-temperature zone, and the stress concentration area, enabling timely detection of high-risk warnings. This provides a scientific basis for boiler operation and maintenance decisions, reduces the failure rate, and ensures long-term stable boiler operation. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0017] Figure 1 A flowchart of a boiler high-temperature heating surface tube over-temperature monitoring and early warning method provided in an embodiment of this application; Figure 2This is a schematic diagram of the structure of the boiler high-temperature heating surface tube over-temperature monitoring and early warning system provided in the embodiment of this application.
[0018] Figure label: 10-Easy Over-Temperature Measurement Point Deployment Module; 20-Displacement Sensor Array Deployment Module; 30-Material Design Information Aggregation Module; 40-Real-Time Wall Temperature Array Comparison Module; 50-Real-Time Over-Temperature Zone Location Module; 60-Finite Element Thermal Stress Fitting Module; 70-Real-Time Level Early Warning Output Module. Detailed Implementation
[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0020] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0021] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0022] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0023] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0024] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0025] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0026] like Figure 1 and Figure 2 As shown in the figure, this application provides a method for monitoring and early warning of overheating of boiler high-temperature heating surface tubes, and a system for monitoring and early warning of overheating of boiler high-temperature heating surface tubes using this method.
[0027] like Figure 1 As shown in the embodiments of this application, the boiler high-temperature heating surface tube over-temperature monitoring and early warning method includes: Step S1: Deploy measurement points in the easily overheated zone of the boiler's high-temperature heating surface tubes to obtain a temperature sensing array; Among them, the high-temperature heating surface tubes of the boiler are the parts most prone to exceeding the temperature limit, especially under certain operating conditions such as high load and deep temperature regulation. The purpose of deploying monitoring points in the easily overheated areas is to monitor the temperature of the boiler tubes in real time, to promptly detect potential overheating areas, and to take early warning measures in advance.
[0028] A temperature sensor array is a system composed of multiple temperature sensors that cover multiple key locations on the high-temperature heating surface tubes of a boiler. This arrangement allows for comprehensive monitoring of the temperature distribution on the boiler's heating surface tubes, timely detection of any possible temperature anomalies, and ensures that the boiler's temperature is controlled within a safe range.
[0029] Step S2: Pre-deploy displacement sensing arrays at key structural locations in the boiler furnace; The key structures of the boiler furnace include supports, support points, and connecting components. These support structures are affected by high temperature, expansion, and thermal stress, and may be subject to displacement or deformation.
[0030] Displacement sensor arrays are pre-deployed at key structural points in the boiler furnace to monitor the deformation of these key structures in real time, providing data support for analyzing the boiler's stress state and safety. These sensors are mainly deployed at load-bearing support points and bends in the boiler, areas prone to stress concentration.
[0031] Step S3: Interact to obtain the material property information of the boiler high-temperature heating surface tubes, and aggregate the material design information based on the material property information to obtain the material design safety threshold. Material property information refers to key characteristics related to the boiler tube material, such as material grade, design temperature, compressive strength, and creep resistance. These properties determine the material's durability and load-bearing capacity under high temperature and high pressure environments. Material property data for the boiler tubes is automatically acquired through interaction with the power plant's SIS (Safety Instrumented System) or IoT platform.
[0032] The material design safety threshold refers to the maximum safe temperature that a material can withstand, calculated based on its material properties. This threshold is the material's design safety limit and is used to determine whether the current temperature of the boiler tube is safe. It is specifically obtained by aggregating information such as the material's grade, design temperature, and alarm temperature to ensure that the temperature of the boiler tube does not exceed the material's design limit, thereby avoiding safety accidents caused by overheating.
[0033] Step S4: In real time, compare whether the real-time wall temperature array returned by the temperature sensing array meets the material design safety threshold. Among them, the real-time wall temperature array is the real-time wall temperature data returned from the temperature sensor array. During the boiler operation, the temperature value returned by each temperature sensor is monitored in real time and compared with the pre-calculated material design safety threshold to determine whether the temperature exceeds the safe range.
[0034] If the conditions are not met, the real-time overheating area is located based on the spatial projection of the real-time wall temperature array onto the high-temperature heating surface tubes of the boiler. During boiler operation, if the temperature data transmitted by the real-time wall temperature array exceeds the material design safety threshold, the real-time overheating area will be located based on the position of the corresponding temperature sensor. The real-time overheating area may cause the boiler tube material to overheat, deteriorate, or even rupture, resulting in safety accidents.
[0035] Step S5: Interactively acquire the real-time operating parameters of the boiler, and combine the expansion data returned by the real-time wall temperature array and displacement sensor array to perform finite element thermal stress fitting to locate the stress concentration area. Among them, by interacting with the power plant's SIS system (i.e., safety instrumented system) or IoT platform, real-time operating parameters such as pressure and load are obtained to indicate the boiler's operating status.
[0036] The expansion data returned by the displacement sensor array provides information on the displacement of the boiler tubes due to thermal expansion.
[0037] Step S6: Based on the spatial correlation characteristics of the real-time over-temperature area and the stress concentration area, output a real-time level warning.
[0038] Compared with the prior art, the boiler high-temperature heating surface tube over-temperature monitoring and early warning method and system provided in this application deploys measurement points in the easily over-temperature zone on the boiler high-temperature heating surface tube to obtain a temperature sensor array, which can acquire temperature data of each measurement point in real time, improves the coverage and accuracy of boiler tube temperature monitoring, and provides a reliable data foundation for subsequent over-temperature early warning.
[0039] By comparing the real-time wall temperature array returned by the temperature sensor array with the design safety threshold in real time, it can promptly identify whether there is an over-temperature risk in the boiler tubes, providing a real-time temperature control feedback mechanism for the safe operation of the boiler. If an over-temperature risk is identified, the real-time over-temperature area is accurately located through spatial projection, efficiently identifying the specific location of the abnormal temperature inside the boiler. At the same time, it provides clear spatial positioning for boiler maintenance personnel, helping to improve maintenance efficiency and enhance the safety of boiler operation.
[0040] By combining real-time operating parameters, expansion data from real-time wall temperature arrays and displacement sensor arrays, finite element thermal stress fitting is performed to locate stress concentration areas. Identification of these stress concentration areas can provide early warning of potential pipe rupture, fatigue, and other fault locations, thereby reducing the occurrence of sudden accidents.
[0041] Furthermore, by comprehensively analyzing the spatial correlation characteristics of real-time overheating areas and stress concentration areas, real-time level early warnings are output. This early warning mechanism can flexibly adjust the early warning level based on the current operating status of the boiler and the current real-time overheating and stress concentration areas, promptly obtaining high-risk warnings, providing a scientific basis for boiler operation and maintenance decisions, reducing the failure rate, and ensuring the long-term stable operation of the boiler.
[0042] Furthermore, in step S1, the specific implementation method may include: Step S11: Based on the initial monitoring accuracy, locate the basic measuring points of the boiler high-temperature heating surface tubes to obtain the initial temperature measuring point distribution. Among them, the basic measurement point location refers to determining the initial number and distribution of measurement points at key locations on the high-temperature heating surface tubes of the boiler, based on the boiler's design, operating load, historical data, and structural characteristics. The purpose of this process is to initially determine the areas in the boiler tubes that need to be monitored and to provide a basis for subsequent optimized deployment.
[0043] Step S12: Locate multiple overheat-prone areas of the boiler's high-temperature heating surface tubes; Among them, the overheating zone refers to the area in the boiler tube where the temperature is prone to exceed the standard. Based on the boiler's design structure, historical operating data and temperature change trends, combined with temperature measurement data and engineering experience, multiple overheating zones of the boiler's heating surface tubes are identified. Overheating zones usually include elbows, connection parts, support points, etc. of the boiler tubes. Due to factors such as thermal expansion and stress concentration, the temperature fluctuates greatly in these locations, so they need to be paid special attention to.
[0044] Step S13: Based on the structural characteristics of the temperature-over-temperature zone, temperature measurement points are located in multiple temperature-over-temperature zones to obtain a structurally optimized measurement point distribution. Among them, structural characteristics refer to the characteristics of temperature changes in different parts of the boiler tube due to factors such as geometry, heat flow distribution, tube bending degree, and support position. In areas prone to overheating, these structural characteristics may lead to uneven temperature distribution and temperature concentration.
[0045] Step S14: The measurement points of the initial temperature measurement point distribution are compensated by the structure-optimized measurement point distribution, and the temperature sensor array is deployed on the high-temperature heating surface tube of the boiler. For example, more measuring points are needed at bends or supports of boiler tubes to ensure coverage of areas with large temperature variations. By analyzing these structural characteristics and optimizing the distribution of measuring points, temperature monitoring in each area prone to overheating can be made more accurate.
[0046] Furthermore, in step S13, the specific implementation method may include: Step S131: Interact to obtain the first structure ID of the boiler structure to which the first overheating zone belongs; Among them, the first overheating zone is any one of the multiple overheating zones. As the current analysis object, the first structure ID is the unique identifier of the first overheating zone in the overall structure of the boiler.
[0047] Step S132: After extracting the first region structural features of the first region prone to overheating, use the first region structural features and the first structure ID as search conditions to search the distribution of the first working fluid flow uneven region and the distribution of the first defect region online. Regional structural characteristics refer to the physical structural features of a specific region of the boiler tubes, such as the tube's geometry (e.g., straight pipes, elbows, connection points), support locations, and heat flow distribution. Uneven fluid flow may exist in the boiler, meaning regions with low fluid velocity due to tube structure or boiler operating conditions cannot adequately distribute heat, easily leading to overheating. Physical defects in the boiler tubes, such as corrosion, wear, and cracks, typically increase thermal stress concentration, making these areas more prone to exceeding temperature limits.
[0048] Step S133: After solving the union of the distribution of the first working fluid flow uneven region and the distribution of the first defect region, the measurement points are deployed in a coverage manner to obtain the first optimized measurement point distribution. Specifically, a spatial overlap analysis is performed on the distribution of the first uneven flow region and the first defect region to determine their union region. Based on the range of the union region, the arrangement of measuring points is optimized to ensure that these high-risk areas are adequately monitored. Specifically, more temperature sensors are deployed around the uneven flow region and the defect region to more accurately monitor temperature changes in these high-risk areas. Sensors are rationally deployed based on the temperature change trends and heat load characteristics of the regions to ensure that overheating phenomena in these regions can be detected in a timely manner.
[0049] Step S134: By analogy, temperature measuring points are located in the multiple areas prone to overheating to obtain multiple optimized measuring point distributions, which constitute the structure-optimized measuring point distribution. Specifically, for each area prone to overheating, based on its structural characteristics, distribution of uneven flow areas and defect areas, a similar optimization method is adopted to arrange an appropriate number and location of measuring points. Through analogy optimization, a structurally optimized measuring point distribution is finally obtained to ensure that all key areas of the boiler's high-temperature heating surface tubes can be fully monitored.
[0050] Preferably, in step S3, the material property information of the boiler's high-temperature heating surface tube can be obtained interactively through local retrieval, and the material property information may specifically include the material grade, material design temperature, and material alarm temperature.
[0051] Furthermore, based on the material grade, historical material degradation data can be retrieved from the metal monitoring database, along with the historical over-temperature duration. This historical material degradation data includes oxide scale thickness, hardness degradation, and wall thickness reduction. Then, based on this historical material degradation data and the aforementioned material design temperature, the aforementioned material alarm temperature can be used to correct for degradation, resulting in a degradation temperature correction threshold. After interacting with the power plant's SIS system (i.e., safety instrumented system) or IoT platform to obtain real-time operating conditions, the aforementioned degradation temperature correction threshold can be modified according to the real-time operating conditions to output the material design safety threshold.
[0052] The material grade indicates the type and performance level of the material. Each material has a different grade based on its chemical composition, physical properties, and temperature resistance. The material design temperature is the maximum operating temperature of the material under standard working conditions. It determines the limit load that the material can withstand at high temperatures. The material alarm temperature refers to the temperature at which the alarm system will be triggered when the actual operating temperature of the material exceeds this temperature, indicating possible overheating or material damage.
[0053] The metal monitoring database stores historical data on material deterioration. Using the material grade as a search criterion, relevant deterioration data is retrieved from the database. This data is typically recorded by the power plant's monitoring system and includes the results of each equipment maintenance and inspection. The material deterioration data reflects the physical changes and degradation of boiler tubes during prolonged high-temperature operation. Specifically, under high-temperature conditions, oxide scale easily forms on the material surface. Excessive oxide scale thickness can affect the material's thermal conductivity and mechanical properties, leading to premature material deterioration. Creep is the result of long-term stress under high temperature and high pressure conditions, causing microstructural changes and resulting in decreased strength and toughness. The historical cumulative overheating time records the cumulative time the material has been under overheating conditions; the longer the overheating time, the more pronounced the fatigue damage and performance degradation of the material.
[0054] The alarm temperature for materials is adjusted for deterioration. For example, if the oxide scale thickness exceeds a certain value, such as 0.5 mm, the effective load-bearing capacity of the material will decrease due to the insulating effect of the oxide scale. Therefore, the alarm temperature needs to be lowered by 5-10°C. If the material has a long history of accumulated overheating, such as more than 100 hours / year, it indicates that the material's high-temperature resistance may have degraded. Therefore, the alarm temperature needs to be lowered by 10-15°C. Through this correction mechanism, the alarm temperature for materials can be dynamically adjusted to ensure that the boiler's true load-bearing capacity after material deterioration is reasonably reflected.
[0055] Real-time operating conditions include key parameters such as boiler load, pressure, and inlet water temperature. These parameters are obtained through interaction with the power plant's SIS system or IoT platform. This data reflects the current operating status of the boiler and affects the temperature and stress distribution of the boiler tubes.
[0056] Scenario-based correction refers to adjusting the degradation temperature correction threshold based on real-time operating conditions. Specifically, based on factors such as the boiler's current load, temperature, and pressure, the alarm temperature correction threshold is appropriately modified to ensure it accurately reflects the boiler's safety under current operating conditions. For example, if the boiler is operating under high load, the alarm temperature threshold needs to be further reduced to prevent overheating. After the above corrections, the final output material design safety threshold is used as the safety threshold for the boiler's high-temperature heating surface tubes.
[0057] Preferably, in step S4, the method for locating the real-time overheating region based on the spatial projection of the real-time wall temperature array onto the high-temperature heating surface tubes of the boiler may specifically include: By comparing the real-time wall temperature array with the material design safety threshold at each measurement point, multiple real-time over-temperature measurement points are obtained. A 3D model of the four boiler tubes covering the high-temperature heating surface tubes is pre-constructed, and the tube segment space region is associated in the 3D model of the four boiler tubes. After projecting multiple real-time over-temperature measurement points onto the tube segment space region, regional association analysis of adjacent over-temperature measurement points is performed to output the real-time over-temperature region, which is marked with the tube segment number and over-temperature extreme value.
[0058] The temperature value returned by each sensor is compared with the material design safety threshold. If the temperature at a certain measuring point exceeds the material design safety threshold, the measuring point is regarded as a real-time over-temperature measuring point.
[0059] The four-tube boiler 3D model is a three-dimensional spatial model of the entire high-temperature heating surface tubes of the boiler, constructed using 3D modeling technology based on the layout and structural design of the boiler tubes. Each tube segment in the four-tube boiler 3D model has specific spatial coordinates, and these regions correspond to different parts of the boiler and have different temperature and stress distribution characteristics.
[0060] In the 3D model of the four boiler tubes, the spatial coordinates of each real-time overheating measurement point are projected onto the tube segment's spatial region, accurately reflecting the specific location of the measurement point within the boiler. Then, a regional correlation analysis is performed on adjacent overheating measurement points, including merging adjacent or nearby points into a single region based on their spatial relationships, identifying real-time overheating areas. These areas represent temperature anomalies caused by overheating within the boiler tubes. Each real-time overheating area is labeled with its corresponding boiler tube segment number, helping maintenance personnel quickly locate the specific segment. Each real-time overheating area is also accompanied by its maximum temperature value, i.e., the overheating extreme value, which helps assess the severity of the risk in that area.
[0061] Preferably, step S5 may specifically include: After constructing a dynamic finite element mesh based on the 3D model of the four-tube boiler, the finite element model of the four-tube boiler is generated by loading real-time operating parameters. These real-time operating parameters may include real-time temperature field, internal pressure load, and expansion displacement constraint. The expansion data returned by the real-time wall temperature array, real-time operating parameters, and displacement sensing array are loaded into the finite element model of the four-tube boiler to solve the transient thermal stress distribution and output the stress concentration area.
[0062] The equivalent stress value in this stress concentration region exceeds 80% of the allowable stress of the material.
[0063] Real-time operating parameters refer to temperature, pressure, and expansion-related data collected during the actual operation of the boiler. These data reflect the current operating status of the boiler tubes. Among them, the real-time temperature field includes the temperature distribution at different locations within the boiler tubes, which is the basic data for determining whether the boiler tubes are overheating; the internal pressure load refers to the pressure distribution data inside the boiler; and the expansion displacement constraint is the displacement data of the boiler tubes caused by thermal expansion.
[0064] Dynamic finite element mesh divides the 3D model of the four boiler tubes into multiple small units. The physical properties and responses (such as stress, temperature, displacement, etc.) within each unit are calculated using the finite element method. As the boiler's operating status changes, the finite element mesh is dynamically adjusted based on real-time monitoring data to ensure that it can accurately reflect the thermal stress distribution of the boiler tubes under different operating conditions.
[0065] The temperature, pressure, and expansion of a boiler change continuously over different time periods. Transient analysis refers to calculating the thermal stress distribution within the boiler tubes in stages over time. Based on inputs such as real-time wall temperature arrays, internal pressure loads, and expansion displacement data, the stress conditions of the boiler tubes at instantaneous moments are calculated. Transient thermal stress distribution refers to the distribution of thermal stress at different locations, such as bends, joints, and support points of the boiler tubes.
[0066] Stress concentration areas refer to regions in boiler tubes where stress is locally concentrated due to structural inhomogeneity or temperature changes under the influence of thermal expansion and internal pressure. These areas may pose a risk of fatigue or material damage and must be taken seriously.
[0067] For these areas, the equivalent stress value is calculated and compared with the allowable stress of the material. When the equivalent stress value exceeds 80% of the allowable stress of the material, the area is considered to be at risk of material failure and requires timely maintenance or reinforcement.
[0068] Preferably, step S6 may specifically include: Spatial coordinate mapping of the real-time overheating region and stress concentration region is performed on the 3D model of the four tubes of the boiler to obtain the spatially overlapping region; the regional temperature extreme value of the spatially overlapping region is retrieved; the percentage of overlapping region is calculated based on the union area of the real-time overheating region and stress concentration region and the spatially overlapping region; the pipe segment number identifier and overheating extreme value identifier of the real-time overheating region, as well as the regional temperature extreme value and the percentage of overlapping region are used as early warning matching conditions, and real-time level early warning is obtained by matching in the early warning rule base.
[0069] The identified real-time overheating and stress concentration areas are mapped onto the 3D model of the boiler's four tubes. Through 3D modeling technology, it is ensured that the real-time overheating and stress concentration areas can be accurately aligned with the boiler's physical structure and the spatial position of each tube section.
[0070] The real-time over-temperature region and the stress concentration region are usually thermal stress-sensitive areas in boiler tubes. They may overlap in space. By mapping spatial coordinates, the intersection of these two regions in three-dimensional space can be identified, that is, the spatially overlapping region.
[0071] By extracting the temperature of each over-temperature measuring point in the spatially overlapping area from the data obtained from the temperature sensing array, the highest temperature in the area is calculated, i.e., the regional temperature extreme value.
[0072] The union area refers to the total area of the real-time overheating region and the stress concentration region, which is the total spatial area of the two combined. By calculating the proportion of the overlapping area to the union area, we can obtain the percentage of the overlapping area in the total area, i.e., the percentage of the overlapping area.
[0073] The pipe section number identifier, over-temperature extreme value identifier, regional temperature extreme value, and percentage of overlapping area are used as early warning matching conditions and matched with the preset early warning rule library. The early warning rule library sets different thresholds and rules according to different boiler operating conditions and risk assessment models. Based on these conditions, different levels of real-time early warning are generated.
[0074] like Figure 2 As shown in the embodiment of this application, the boiler high-temperature heating surface tube overheat monitoring and early warning system includes: an easy-overheating measurement point deployment module 10, used to deploy easy-overheating measurement points on the boiler high-temperature heating surface tube to obtain a temperature sensor array; a displacement sensor array deployment module 20, used to pre-deploy displacement sensor arrays at key structural locations in the boiler furnace; a material design information aggregation module 30, used to interactively obtain material property information of the boiler high-temperature heating surface tube, and aggregate material design information based on the material property information to obtain a material design safety threshold; a real-time wall temperature array comparison module 40, used to compare in real-time whether the real-time wall temperature array returned by the temperature sensor array meets the material design safety threshold; and a real-time overheating area positioning module. The positioning module 50 is used to locate the real-time overheating area based on the spatial projection of the real-time wall temperature array onto the high-temperature heating surface tubes of the boiler; the finite element thermal stress fitting module 60 is used to interactively acquire the real-time operating parameters of the boiler and combine them with the expansion data returned by the real-time wall temperature array and displacement sensor array to perform finite element thermal stress fitting and locate the stress concentration area; the real-time level warning output module 70 is used to output a real-time level warning based on the spatial correlation characteristics of the real-time overheating area and the stress concentration area; and the system control module controls the collaborative operation of the aforementioned modules according to the logical sequence of operation of the aforementioned method embodiments to realize the boiler high-temperature heating surface tube overheating monitoring and warning method provided by the aforementioned embodiments.
[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.
Claims
1. A method for monitoring and early warning of overheating of high-temperature heating surface tubes in a boiler, characterized in that, include: Step S1: Deploy measurement points in the easily overheated zone of the boiler's high-temperature heating surface tubes to obtain a temperature sensing array; Step S2: Pre-deploy displacement sensing arrays at key structural locations in the boiler furnace; Step S3: Interact to obtain the material property information of the high-temperature heating surface tube of the boiler, and aggregate the material design information based on the material property information to obtain the material design safety threshold. Step S4: In real time, compare whether the real-time wall temperature array returned by the temperature sensing array meets the material design safety threshold. If the conditions are not met, the real-time overheating area is located based on the spatial projection of the real-time wall temperature array onto the high-temperature heating surface tubes of the boiler. Step S5: Interact with the boiler to obtain real-time operating parameters, and combine the expansion data returned by the real-time wall temperature array and the displacement sensing array to perform finite element thermal stress fitting to locate the stress concentration area. Step S6: Based on the spatial correlation characteristics between the real-time over-temperature region and the stress concentration region, output a real-time level warning.
2. The boiler high-temperature heating surface tube over-temperature monitoring and early warning method according to claim 1, characterized in that, In step S3, the material property information of the boiler high-temperature heating surface tube is obtained interactively through local retrieval, and the material property information includes material grade, material design temperature and material alarm temperature.
3. The boiler high-temperature heating surface tube over-temperature monitoring and early warning method according to claim 2, characterized in that, Step S3 further includes: retrieving historical material degradation data from a metal monitoring database based on the material grade, and associating it with historical overheating durations. The historical material degradation data includes oxide scale thickness, hardness degradation, and wall thickness reduction. Based on the historical material degradation data and the material design temperature, the material alarm temperature is used to correct for degradation, thereby obtaining a degradation temperature correction threshold. After interactively obtaining real-time operating conditions, the degradation temperature correction threshold is modified according to the real-time operating conditions, and the material design safety threshold is output.
4. The boiler high-temperature heating surface tube over-temperature monitoring and early warning method according to any one of claims 1 to 3, characterized in that, In step S4, the method for locating the real-time overheating region based on the spatial projection of the real-time wall temperature array onto the high-temperature heating surface tubes of the boiler includes: By comparing the real-time wall temperature array with the material design safety threshold at each measurement point, multiple real-time over-temperature measurement points are obtained. A 3D model of four boiler tubes covering the high-temperature heating surface tubes of the boiler is pre-constructed, and the spatial regions of the tube segments are associated in the 3D model of four boiler tubes. After projecting the multiple real-time over-temperature measurement points onto the pipe segment space region, regional correlation analysis is performed on adjacent over-temperature measurement points to output the real-time over-temperature region, which is marked with a pipe segment number and an over-temperature extreme value.
5. The boiler high-temperature heating surface tube over-temperature monitoring and early warning method according to claim 4, characterized in that, Step S5 includes: After constructing a dynamic finite element mesh based on the 3D model of the four-tube boiler, the finite element model of the four-tube boiler is generated by loading the real-time operating parameters, which include the real-time temperature field, internal pressure load and expansion displacement constraint. The real-time wall temperature array, the real-time operating parameters, and the expansion data returned by the displacement sensing array are loaded into the four-tube finite element model of the boiler to solve for transient thermal stress distribution and output the stress concentration region.
6. The boiler high-temperature heating surface tube over-temperature monitoring and early warning method according to claim 5, characterized in that, Step S6 includes: Spatial coordinate mapping of the real-time overheating region and the stress concentration region is performed on the 3D model of the four tubes of the boiler to obtain the spatially overlapping region. Retrieve the extreme regional temperatures of the overlapping spatial regions; The percentage of overlapping area is calculated based on the union area of the real-time overheating region and the stress concentration region and the spatially overlapping region. The real-time level warning is obtained by matching the pipe segment number identifier and the over-temperature extreme value identifier of the real-time over-temperature zone, as well as the temperature extreme value of the zone and the percentage of the overlapping area, in the warning rule base.
7. The boiler high-temperature heating surface tube over-temperature monitoring and early warning method according to claim 1, characterized in that, Step S1 includes: Step S11: Based on the initial monitoring accuracy, locate the basic measuring points of the high-temperature heating surface tubes of the boiler to obtain the initial temperature measuring point distribution; Step S12: Locate multiple overheat-prone areas of the boiler's high-temperature heating surface tubes; Step S13: Based on the structural characteristics of the temperature-overheating regions, temperature measurement points are located in the multiple temperature-overheating regions to obtain a structurally optimized measurement point distribution. Step S14: The compensation results of the initial temperature measuring point distribution are obtained by using the structure-optimized measuring point distribution, and a temperature sensing array is deployed on the high-temperature heating surface tube of the boiler.
8. The boiler high-temperature heating surface tube over-temperature monitoring and early warning method according to claim 7, characterized in that, Step S13 includes: Step S131: Interact to obtain the first structure ID of the boiler structure to which the first overheating zone belongs; Step S132: After extracting the first region structural features of the first region prone to overheating, use the first region structural features and the first structure ID as search conditions to search the distribution of the first working fluid uneven flow region and the distribution of the first defect region online. Step S133: After solving the union of the distribution of the first uneven flow region of the working fluid and the distribution of the first defect region, the measurement points are deployed in a coverage manner to obtain the first optimized measurement point distribution. Step S134: By analogy, temperature measuring points are located in the multiple areas prone to overheating to obtain multiple optimized measuring point distributions, which constitute the structure-optimized measuring point distribution.
9. The boiler high-temperature heating surface tube over-temperature monitoring and early warning method according to claim 8, characterized in that, Step S133 includes: performing spatial overlap analysis on the distribution of the first uneven flow region of the working fluid and the distribution of the first defect region to determine the union region, and optimizing the arrangement of measuring points based on the range of the union region.
10. A boiler high-temperature heating surface tube over-temperature monitoring and early warning system, characterized in that, The boiler high-temperature heating surface tube overheating monitoring and early warning method applied to any one of claims 1 to 9, the system includes: an easy overheating measurement point deployment module, a displacement sensor array deployment module, a material design information aggregation module, a real-time wall temperature array comparison module, a real-time overheating area positioning module, a finite element thermal stress fitting module, and a real-time level early warning output module, as well as a system control module.