Turbine rotor performance evaluation and life prediction method, device, medium and equipment

Abstract

The present disclosure relates to the technical field of steam turbine state evaluation, and provides a steam turbine rotor performance evaluation and life prediction method, device, medium and equipment, comprising: obtaining an evaluation data set of a steam turbine rotor to be evaluated; dividing the operation process of the steam turbine rotor to be evaluated into multiple working condition sections based on operation data; dividing the steam turbine rotor to be evaluated into multiple evaluation sub-zones based on structure data and operation data; determining damage evaluation information of each evaluation sub-zone according to the operation data corresponding to each working condition section; performing sub-zone corresponding checking on the damage evaluation information of each evaluation sub-zone and the overhaul detection data corresponding to each evaluation sub-zone, and determining residual life information of the steam turbine rotor to be evaluated based on the checking result. In this embodiment, the rotor operation process is divided into multiple working condition sections, the structure is divided into multiple evaluation sub-zones, and the sub-zone checking is performed in combination with the overhaul detection data, thereby realizing accurate prediction of the residual life of the steam turbine rotor and effective improvement of the operation reliability.

Description

Technical Field

[0001] This disclosure relates to the field of steam turbine condition assessment technology, and more specifically, to a method, apparatus, medium, and equipment for steam turbine rotor performance assessment and life prediction. Background Technology

[0002] As deep peak shaving and wide-load operation of thermal power units become increasingly common, the alternating thermal stress and centrifugal force coupled to the turbine rotor under frequent start-ups and shutdowns and load fluctuations are significantly enhanced. This leads to increasingly severe problems of low-cycle fatigue and high-temperature creep cumulative damage. Accurately assessing the rotor's remaining life is of great engineering significance for ensuring the safe and extended operation of the unit. At the same time, the need for life extension of in-service units is becoming increasingly urgent, placing higher demands on the accuracy of life assessment.

[0003] However, the turbine rotor has a complex geometry, and the stress and strain field distributions of each stage of the impeller along the axial direction and local areas such as the radial center hole and blade root grooves are significantly different. Moreover, the actual operation process covers a variety of transient and steady conditions, and the contribution of different stages to damage varies greatly, which makes the rotor damage evolution exhibit significant non-uniformity and time-varying characteristics.

[0004] In related technologies, the life assessment of steam turbine rotors often uses finite element numerical simulation to calculate the overall stress distribution and combines it with linear cumulative damage theory to estimate fatigue and creep damage. However, this method usually treats the rotor as a single whole for macroscopic analysis, and the assessment results are difficult to accurately reflect the true damage state of each part of the rotor. Summary of the Invention

[0005] This disclosure provides at least one method, apparatus, medium, and equipment for evaluating the performance and predicting the life of a steam turbine rotor. By dividing the rotor operation process into multiple operating condition segments and the structure into multiple evaluation zones, and combining maintenance and testing data for zone verification, it achieves accurate prediction of the remaining life of the steam turbine rotor and effectively improves its operational reliability.

[0006] This disclosure provides a method for evaluating the performance and predicting the lifespan of a steam turbine rotor, including: Obtain the evaluation dataset of the turbine rotor to be evaluated; wherein, the evaluation dataset includes structural data, operational data, and maintenance and inspection data; Based on the operational data, the operating process of the turbine rotor to be evaluated is divided into multiple operating condition segments; and based on the structural data and the operational data, the turbine rotor to be evaluated is divided into multiple evaluation zones. Based on the operating data corresponding to each of the aforementioned operating conditions, the damage assessment information for each of the aforementioned assessment zones is determined; The damage assessment information of each assessment zone is checked against the maintenance and inspection data corresponding to each assessment zone, and the remaining life information of the turbine rotor to be assessed is determined based on the check results.

[0007] This disclosure provides a device for evaluating the performance and predicting the lifespan of a steam turbine rotor, comprising: The data acquisition module is used to acquire the evaluation dataset of the turbine rotor to be evaluated; wherein, the evaluation dataset includes structural data, operational data, and maintenance and inspection data; The region division module is used to divide the operating process of the turbine rotor to be evaluated into multiple operating condition segments based on the operating data; and to divide the turbine rotor to be evaluated into multiple evaluation zones based on the structural data and the operating data. The damage assessment module is used to determine the damage assessment information of each assessment zone based on the operating data corresponding to each of the operating conditions. The lifespan determination module is used to perform partition-based verification of the damage assessment information of each assessment partition with the maintenance and inspection data corresponding to each assessment partition, and determine the remaining lifespan information of the turbine rotor to be assessed based on the verification results.

[0008] This disclosure provides a computer device, including a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the computer device is running, the processor communicates with the memory via the bus. When the machine-readable instructions are executed by the processor, they perform the turbine rotor performance evaluation and life prediction method as described in any of the above possible embodiments.

[0009] This disclosure provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the turbine rotor performance evaluation and life prediction method as described in any of the above possible embodiments.

[0010] The turbine rotor performance evaluation and life prediction method, apparatus, medium, and equipment provided in this disclosure divide the turbine rotor's operation process into multiple operating condition segments and divides the rotor into multiple evaluation zones based on structural and operational data. This achieves differentiated characterization of damage evolution in different regions of the rotor under specific operating stages, significantly improving the pertinence and accuracy of damage evaluation. Simultaneously, by verifying the damage evaluation information of each evaluation zone against the corresponding zone's actual maintenance and inspection data zone by zone, the deviation between theoretical calculations and engineering measurements can be effectively corrected, eliminating the cumulative error caused by a single global evaluation. This significantly improves the reliability and engineering credibility of the remaining life prediction results, helping to extend the rotor's service life while ensuring operational safety.

[0011] To make the above-mentioned objects, features and advantages of this disclosure more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0012] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings referenced in the embodiments will be briefly described below. These drawings are incorporated in and constitute a part of this specification. They illustrate embodiments conforming to this disclosure and, together with the specification, serve to explain the technical solutions of this disclosure. It should be understood that the following drawings only show some embodiments of this disclosure and should not be considered as limiting the scope. Those skilled in the art can obtain other related drawings based on these drawings without creative effort.

[0013] Figure 1 A flowchart of a method for evaluating the performance and predicting the life of a steam turbine rotor provided in an embodiment of this disclosure is shown; Figure 2 A flowchart of an evaluation partitioning method provided by an embodiment of this disclosure is shown; Figure 3 A flowchart of a method for determining damage assessment information provided by an embodiment of this disclosure is shown; Figure 4 A flowchart of a method for generating operational suggestion information provided in an embodiment of this disclosure is shown; Figure 5 This diagram illustrates the structure of a turbine rotor performance evaluation and life prediction device provided in an embodiment of this disclosure. Figure 6 A schematic diagram of the structure of a computer device provided in an embodiment of this disclosure is shown. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. The components of the embodiments of this disclosure described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this disclosure provided in the accompanying drawings is not intended to limit the scope of the claimed disclosure, but merely represents selected embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without inventive effort are within the scope of protection of this disclosure.

[0015] 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.

[0016] In this document, the term "and / or" merely describes a relationship, indicating that three relationships can exist. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. Furthermore, the term "at least one" in this document means any combination of at least two of any one or more elements. For example, including at least one of A, B, and C can mean including any one or more elements selected from the set consisting of A, B, and C.

[0017] To facilitate understanding of this embodiment, the executing entity of the turbine rotor performance evaluation and life prediction method provided in this disclosure will first be described in detail. The executing entity of the turbine rotor performance evaluation and life prediction method provided in this disclosure is a computer device. This computer device can be a terminal device or a server. The terminal device can also be a mobile device, user terminal, terminal, handheld device, computing device, vehicle-mounted device, wearable device, etc. The server can be an independent physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud storage, big data, and artificial intelligence platforms. Optionally, this method can also be applied to an implementation environment composed of computer equipment and servers.

[0018] The method for evaluating the performance and predicting the lifespan of a steam turbine rotor provided in this application will be described in detail below with reference to the accompanying drawings. See also Figure 1 The diagram shows a flowchart of a method for evaluating the performance and predicting the lifespan of a steam turbine rotor according to an embodiment of this disclosure. The method includes the following steps S101 to S104: S101, Obtain the evaluation dataset of the turbine rotor to be evaluated.

[0019] Understandably, the turbine rotor to be evaluated refers to a turbine rotor component that has completed a certain period of service and requires a reassessment of its current condition. The turbine rotor is the core rotating component in a turbine unit, used to convert the thermal energy of high-temperature, high-pressure steam into mechanical energy, which drives a generator to produce electrical energy. During operation, this rotor is subjected to a long-term service environment of high temperature, high pressure, and high-speed rotation. Its structure is typically divided into multiple stages along the axial direction. Each stage includes an impeller and moving blades mounted on the impeller. The rotor has journal sections at both ends for support, and a center hole is machined along the axial direction at the center of the rotor. Different degrees of geometric abrupt changes exist at the impeller roots, shoulder transitions, and shaft seals of each stage. The turbine rotors to be evaluated can be categorized into different material batches based on their manufacturing batches. For example, rotors made of FB2 material and rotors made of 30Cr1Mo1V material exhibit significant differences in high-temperature creep strength, low-cycle fatigue performance, and creep characteristics, resulting in different life assessment curves and damage accumulation patterns. They can also be categorized into different operational history types based on their service experience. For instance, rotors operating under basic load for extended periods are primarily damaged by high-temperature creep, while rotors undergoing frequent start-stop peak-shaving operations are primarily damaged by low-cycle fatigue. Rotors that have experienced abnormal transient events such as load shedding or overspeeding also suffer additional damage from impact loads. Furthermore, they can be categorized into different structural configurations based on their structural design. For example, rotors with a central bore and solid rotors without a central bore, welded rotors and forged rotors, as well as rotors with different impeller stages and shaft diameters. The stress concentration locations and stress distribution characteristics of rotors with different structural configurations vary considerably, directly affecting the zoning of the evaluation areas and the key areas of focus for damage calculation.

[0020] Here, the evaluation dataset corresponding to the turbine rotor to be evaluated refers to the dataset that provides information on the rotor's original design state, actual service history, and measured state after operation. It serves as the fundamental data source for subsequent determination of operating condition sections, evaluation zones, and damage assessment information. The evaluation dataset specifically includes structural data, operational data, and maintenance and inspection data.

[0021] Specifically, structural data refers to data used to characterize the inherent physical properties and design and manufacturing status of the turbine rotor to be evaluated. This data can be used to express information such as the rotor's geometric configuration, material properties, manufacturing process, and maintenance history. Specifically, it can include design drawings, material quality certificates, heat treatment records, factory mechanical performance records, factory non-destructive testing records, and maintenance records of the turbine rotor to be evaluated. The design drawings of the turbine rotor to be evaluated are a digital representation of the rotor's engineering drawings, providing geometric parameters such as the geometric dimensions of each impeller stage, journal diameter, center hole diameter, transition fillet radius, axial spacing of each stage, and design tolerances for each part. The material quality certificates are the technical data in the quality certificates provided by the supplier with the raw materials used in the rotor. This information can be used to determine whether the chemical composition, furnace number, batch number, and various mechanical performance indicators of the rotor materials meet the procurement technical requirements at the time of delivery. Heat treatment record information refers to the records of process parameters for each heat treatment performed on the rotor during manufacturing. Specifically, this may include normalizing temperature, normalizing holding time, tempering temperature, tempering holding time, and cooling method. Factory mechanical property record information consists of measured data from the mechanical property inspection report provided with the rotor after processing at the manufacturer. This data provides the rotor material's yield strength, tensile strength, elongation after fracture, reduction of area, and impact absorption energy in its factory condition. Factory non-destructive testing record information comprises the original records and evaluation conclusions generated after the rotor has been processed at the manufacturer, using non-destructive testing methods to inspect various parts of the rotor. This data provides the location, size, and evaluation level of internal and surface defects at the time of the rotor's shipment. The maintenance records are written records of the rotor after each unit overhaul, showing the inspection and maintenance of the rotor. They can provide the inspection data of various parts of the rotor during each overhaul, the defects or abnormalities found, and the repair measures taken. They can reflect the evolution of damage to the rotor over time during its service life.

[0022] Specifically, operational data refers to the process data related to the operating status of the turbine rotor under evaluation, collected and stored by the unit control system and field monitoring instruments throughout its entire service life. It records the external conditions such as temperature, pressure, load, and speed actually experienced by the rotor. Operational data specifically includes steam temperature data, steam pressure data, unit load data, rotor speed data, start-up and shutdown time data, load increase / decrease process data, cumulative operating time data, and abnormal operating event records for the turbine rotor under evaluation during operation. Among these, steam temperature data is a sequence of temperature values ​​collected from temperature measuring points at each extraction port and main steam pipeline during unit operation, reflecting the temperature level of the environment in which various parts of the rotor are located during operation. Steam pressure data is a sequence of pressure values ​​collected from pressure measuring points at the main steam pipeline and extraction ports at each stage during unit operation, reflecting the steam pressure level experienced by various parts of the rotor. Unit load data is a real-time recorded value of the generator output power during unit operation, representing the magnitude of the mechanical power transmitted by the rotor. Rotor speed data is a sequence of rotational speed values ​​collected by speed sensors installed at the rotor end during unit operation, indicating the actual rotational speed of the rotor. Start-up and shutdown time data records the specific time and duration of each unit start-up and shutdown operation, determining the number of cold, warm, and hot starts experienced by the rotor, as well as the corresponding temperature and speed-up rates for each start-up method. Load increase / decrease process data shows the load change over time during each load increase and decrease operation, determining the number of load changes and the rate of load change experienced by the rotor. Cumulative operating time data is the total operating time of the rotor since commissioning, along with the time distribution within each load range. Abnormal operating event record data is a detailed record of events deviating from normal operating conditions during unit operation, specifically including the time and magnitude of load shedding events, the maximum speed and duration of overspeed events, the triggering cause and time of abnormal shutdowns, the temperature and rate of cooling medium during rapid cooling operations, and the time and magnitude of vibration abrupt changes.

[0023] Specifically, maintenance and testing data refers to the measured results obtained by on-site maintenance personnel using various testing methods to conduct on-site inspections of various parts of the turbine rotor under evaluation during post-operation maintenance. This data can be used for zonal verification with the damage assessment information calculation results. Specifically, it can include hardness test data, ultrasonic test data, phased array test data, magnetic particle test data, penetrant test data, metallographic test data, rotor bending amount test data, roundness test data, coaxiality test data, and vibration analysis data obtained during the post-operation maintenance of the turbine rotor under evaluation.

[0024] The hardness test data consists of hardness values ​​measured on the surface of various test parts of the rotor using a portable hardness tester. These values ​​are used to indirectly infer whether the rotor material has undergone structural aging by observing changes in hardness. The ultrasonic test data consists of the location and equivalent size of defects recorded after an ultrasonic flaw detector emits ultrasonic waves into the rotor and receives the echo signals. This data can detect the presence of volumetric defects such as cracks, inclusions, or white spots inside the rotor. The phased array test data is obtained by electronically controlling the excitation timing of multiple ultrasonic transducer crystals using a phased array ultrasonic testing instrument to achieve beam deflection and focusing. Scanning image data enables internal defect detection and dimensional quantification in areas with complex rotor geometry. Magnetic particle inspection data, obtained by applying a magnetic field to the rotor surface and spraying magnetic powder using a magnetic particle flaw detector, shows the location and shape of defects by observing the magnetic traces formed when the magnetic powder accumulates at the defects. This data can be used to detect cracks, hairline cracks, or folds on and near the rotor surface. Penetrant testing data, obtained by applying a dye-containing penetrant to the inspected surface of the rotor and developing the image, shows the location and morphology of defects by observing the seepage at the defects. This data can be used to detect open defects on the rotor surface. Metallographic testing data consists of metallographic images and rating conclusions obtained from various tested areas of the rotor using a portable metallographic microscope. These images are used to observe the grain size, microstructure, and microstructural changes of the rotor material, such as grain boundary creep voids or carbide precipitation. Rotor bending data is calculated by measuring the radial runout at each journal of the rotor during rotation using a dial indicator. This determines whether the rotor has undergone plastic bending deformation. Roundness data is calculated by measuring the diameter in multiple directions at each journal and the outer edge of the impeller using an outside micrometer. The cross-sectional roundness deviation value can be used to determine whether the rotating cross sections of the rotor have been out of round; the coaxiality detection data is the coaxiality deviation value of the outer edge of the impeller and the journal of each stage of the rotor relative to the central axis of the rotor, which is measured by a laser alignment instrument and can be used to determine whether the stage of the rotor has been eccentric or offset; the vibration analysis data is the vibration amplitude, vibration frequency and vibration phase data obtained by the frequency spectrum analysis after the rotor vibration signal is collected by the speed sensor and acceleration sensor installed on the bearing housing, which can be used to determine whether the rotor has vibration faults such as imbalance, misalignment, oil film oscillation or dynamic and static rubbing.

[0025] In some possible embodiments, to ensure the validity and traceability of the assessment dataset, various types of data in the dataset can be verified, recording the data source, time range, sampling interval, measurement point location, and verification status for each type of data, forming a data quality record for each type of data. Data whose source cannot be clearly traced, whose recording time is obviously discontinuous and cannot be verified through other means, or whose data values ​​do not conform to the relationship between adjacent physical quantities, are marked as restricted-use data. Restricted-use data is used only as reference data in subsequent damage assessment information calculations and is not used as the sole basis for forming assessment conclusions, in order to eliminate the interference of unreliable data on the accuracy of the assessment results.

[0026] In some possible embodiments, considering the potential differences in sampling frequency and recording granularity among different types of data in the evaluation dataset, data cleaning operations such as time alignment and unit unification can be performed after acquiring the evaluation dataset. Time alignment refers to interpolating and resampling data sequences with different sampling frequencies, such as steam temperature data, steam pressure data, unit load data, and rotor speed data, according to a unified time coordinate, so that the physical quantities at the same moment are comparable and correlated; unit unification refers to converting the units of all physical quantities in the evaluation dataset to the same unit system to avoid errors in subsequent numerical calculations due to mixed units.

[0027] In some other embodiments, the aforementioned evaluation dataset may use one or more types of data included in each of the structural data, operational data, and maintenance and inspection data mentioned above. In addition, it may include on-site inspection data such as surface dye penetrant testing data and eddy current testing data recorded by the rotor during each maintenance. Alternatively, it may include dynamic balance test data of the rotor at the time of leaving the factory and dynamic balance retest data after each maintenance. Those skilled in the art may appropriately supplement or delete the specific content of the evaluation dataset according to the completeness of the actual unit's data and the differences in on-site inspection conditions, without making specific limitations here.

[0028] S102, based on the operating data, the operating process of the turbine rotor to be evaluated is divided into multiple operating condition segments; and based on the structural data and the operating data, the turbine rotor to be evaluated is divided into multiple evaluation zones.

[0029] Furthermore, after obtaining the operating data of the turbine rotor to be evaluated, the entire operating process of the turbine rotor can be divided into multiple operating condition segments based on the start-up and shutdown time data, load increase / decrease process data, and cumulative operating time data in the operating data, thus obtaining the corresponding subset of operating data for each operating condition segment. Here, an operating condition segment refers to a time interval obtained by dividing the continuous operating time axis according to the unit's operating state and load change characteristics. It is the basic unit of time for subsequent temperature history analysis, stress history analysis, and load cycle counting, and can include operating conditions such as start-up operating condition segments, steady-state high-temperature operating condition segments, peak-shaving operating condition segments, and shutdown operating condition segments.

[0030] Here, when dividing the rotor's operating process into different operating conditions, operating condition boundaries can be identified based on parameters such as the unit start / stop flags, load change rate, and load stability duration recorded in the operating data. This allows for the determination of the start-up and grid connection times for each start-up process, the disconnection and coasting end times for each shutdown process, the start and end times for each steady-state operation segment, and the start and end times for each load decrease and load increase during peak-shaving processes. Each operating condition segment corresponds to a continuous time interval, with at least one set of steam temperature data, steam pressure data, unit load data, and rotor speed data for that time interval. Furthermore, since abnormal transient events deviating from normal operating conditions may occur during rotor operation, although these events are short-lived, their contribution to rotor damage is not negligible. Therefore, abnormal operating events recorded in the operating data can be processed separately, establishing separate abnormal transient operating condition segments to include load shedding events, overspeed events, abnormal shutdown events, rapid cooling events, and sudden vibration events within the evaluation scope.

[0031] Understandably, due to significant differences in temperature, stress, and load cycle amplitude across different parts of the rotor during operation, the damage accumulation rate and primary damage mechanism may differ for each evaluation zone. Therefore, after dividing the rotor's operating process into service condition segments using operational data, the rotor can be further divided into spatial regions based on structural and operational data. This allows for more refined rotor performance evaluation and life prediction at the level of each evaluation zone. An evaluation zone represents a three-dimensional spatial region obtained by dividing the rotor's geometric space according to structural characteristics, service temperature level, stress concentration, and detection accessibility. It corresponds to a specific physical part of the rotor and is the smallest spatial unit for damage calculation and mapping of detection results.

[0032] Specifically, the design drawings in the structural data provide detailed axial and radial geometry of the rotor; the steam temperature data in the operational data provides information on the temperature environment of various parts of the rotor during service; and the maintenance records provide information on parts of the rotor that have experienced abnormalities in the past. Therefore, when dividing the turbine rotor to be evaluated into multiple evaluation zones, refer to... Figure 2 As shown, the steps S201~S204 may be included: S201, based on the design drawing information in the structural data, determine the journal area, disk or impeller transition area, geometric change area, shaft seal area, and area adjacent to the center hole or inner hole on the turbine rotor to be evaluated.

[0033] Here, based on the axial dimensions, diameter dimensions, transition fillet radii, and local structural features of each rotor stage marked in the design drawings, combined with industry experience, we can identify locations on the rotor where geometric configurations change abruptly and areas experiencing significant stress concentration. This allows us to determine the structural feature areas requiring focused attention. Specifically, the journal region, the shaft sections at both ends of the rotor that support it on the bearings, is a critical area for vibration transmission and load support. The impeller-disc transition region refers to the transition sections where the diameter changes significantly between the impeller rim and wheel surface, and between the impeller root and the rotor body. This indicates locations where the geometric dimensions of each impeller stage change abruptly with the rotor body, and this region experiences significant stress concentration under centrifugal loads. Geometric abrupt change regions refer to locations on the rotor's outer surface where the axial diameter changes drastically. These can include shoulder transitions, the root of the steam seal teeth, the balance piston, and step locations where the diameter changes abruptly between stages. Geometric discontinuities at these locations cause distortion of the local stress field. The shaft seal area is the part of the rotor that passes through the cylinder shaft seal holes at both ends. It prevents steam from leaking outward along the rotor. This area is affected by the temperature changes of the steam supplied to the shaft seal during unit start-up and shutdown, and its surface temperature changes rapidly. The area adjacent to the center hole or inner hole refers to the inner surface of the through hole or blind hole machined along the rotor's central axis and the adjacent internal material area of ​​the rotor. It is a sensitive area for the propagation of internal defects in the rotor.

[0034] In some possible embodiments, due to the differences in the structural design of different models of steam turbine rotors, the identified structural feature areas may only be a few of the five areas mentioned in step S201 above, or there may be more areas that need to be focused on than the above areas. Specifically, the identification and determination can be based on the design drawings of the actual rotor to be evaluated, and no specific limitation is made here.

[0035] S202, Based on the design drawing information in the structural data and the steam temperature data in the operating data, determine the high-temperature steam action area on the turbine rotor to be evaluated.

[0036] Understandably, the steam temperature decreases progressively along the turbine's flow path, resulting in significant temperature differences between each impeller stage. The high-temperature impellers operate at consistently higher temperatures, leading to a significantly higher rate of creep damage accumulation compared to the mid- and low-temperature impellers. Therefore, based on the steam temperature data corresponding to each stage's extraction port under various load conditions in the operating data, and combined with the axial position correspondence between each impeller stage and its extraction port in the design drawings, the temperature distribution experienced by each axial position of the rotor during service can be determined. This allows for the selection of several impellers with consistently high operating temperatures and their adjacent shaft sections as the high-temperature steam impact zone. This high-temperature steam impact zone experiences even higher metal temperatures during operation, resulting in lower high-temperature creep strength margins and faster creep damage accumulation. It is the axial section that requires focused attention during creep damage assessment of this rotor.

[0037] S203, Based on the maintenance record information in the structural data, determine the historical abnormality area on the turbine rotor to be evaluated.

[0038] Specifically, the maintenance records document the locations and types of defects discovered during each maintenance of the rotor through non-destructive testing, areas of abnormal hardness identified by hardness testing, areas of abnormal microstructure discovered by metallographic testing, and locations of abnormal vibration responses identified by vibration analysis. Based on the abnormal detection results recorded in the maintenance records and their corresponding axial and circumferential positions of the rotor, historical abnormal areas on the rotor where defects or abnormalities have previously occurred can be identified. These areas will then be included as part of the subsequent evaluation zoning for focused tracking and re-inspection. These historical abnormal areas may have a tendency for defect expansion, or they may have been repaired during maintenance. Regardless of whether they have been repaired, these areas are areas that require continuous monitoring in subsequent evaluations.

[0039] S204, two or more of the journal region, the impeller or wheel transition region, the geometric change region, the shaft seal region, the region adjacent to the center hole or inner hole, the high-temperature steam action region, and the historical abnormality region are designated as the evaluation partitions.

[0040] Furthermore, after obtaining the above-mentioned structural characteristic regions and operational characteristic regions, in order to perform targeted calculations and evaluations on the parts of the rotor with different damage mechanisms and damage rates, two or more of the journal region, impeller or wheel transition region, geometric change region, shaft seal region, central hole or inner hole adjacent region, high-temperature steam action region, and historical abnormal region can be combined as the evaluation partition set of the rotor, so as to determine the damage evaluation information of each evaluation partition in the subsequent process.

[0041] It should be noted that when a certain part belongs to multiple of the above-mentioned area types, it can be classified into one of the area types as an assessment zone, or it can be classified as an overlapping area of ​​multiple area types and divided into a separate assessment zone. The specific classification method can be determined based on the actual stress level and damage risk of the part.

[0042] In this embodiment of the disclosure, by dividing the operating data into operating condition segments and combining structural data with operating data into evaluation partitions, the time segmentation of the operating process and the spatial partitioning of the rotor structure are realized, so that targeted damage calculations can be performed on different evaluation partitions under different operating condition segments in subsequent steps, thereby improving the precision of damage assessment.

[0043] S103, Based on the operating data corresponding to each of the aforementioned operating conditions, determine the damage assessment information for each of the aforementioned assessment zones.

[0044] Furthermore, after completing the division of operating conditions and evaluation zones, since the temperature load, mechanical load, and cyclic load applied to each evaluation zone of the rotor differ across operating conditions, damage calculations can be performed on each evaluation zone based on the corresponding operating data for each operating condition. This allows for the determination of the accumulated damage level of each evaluation zone during its current service life. Specifically, the loads borne by each evaluation zone during operation mainly include creep loads under prolonged high-temperature conditions, low-cycle fatigue loads caused by start-up, shutdown, and load fluctuations, as well as creep-fatigue interactive loads generated under alternating high-temperature load maintenance and load cycles. After calculating the damage contribution of these three loads to the rotor separately, the calculation results are comprehensively evaluated to obtain the damage assessment information corresponding to each evaluation zone.

[0045] In some possible embodiments, considering that the main factors affecting the damage state of each assessment zone are temperature history, stress level, and number of load cycles, the damage assessment information for each assessment zone is determined by referring to... Figure 3 As shown, the following steps S301~S304 may be included: S301, based on the operating data corresponding to each operating condition segment, determine the temperature history information, stress state information and load cycle information of each evaluation zone during operation.

[0046] Specifically, temperature history information refers to a complete record of the metal temperature change over time for each evaluation zone throughout its service life. It represents the temperature level of the zone at different times, as well as the rate and magnitude of temperature change, and is the fundamental input for determining the degree of high-temperature creep strength degradation in creep damage calculations. Stress state information refers to the distribution of equivalent stress or principal stresses experienced by each evaluation zone during operation over time. It is a comprehensive characterization of the internal stress level of the zone under the combined action of centrifugal loads, thermal loads, and torsional loads, and can be used to determine the allowable creep life of the zone at a given temperature. Load cycle information is the statistical result of the amplitude, mean, and number of stress or strain cycles experienced by each evaluation zone during its service life, which can be used to determine the fatigue life consumption of the zone under each cycle category.

[0047] For example, when determining the above information for each zone based on the operating data corresponding to each operating condition, the finite element analysis method can be used. First, a three-dimensional finite element model of the turbine rotor to be evaluated is established. The steam temperature boundary conditions and heat transfer coefficient corresponding to each operating condition are applied to the model, and transient thermal analysis is performed to obtain the temperature field change of each node of the rotor over time, thereby extracting the temperature history information corresponding to each evaluation zone. Second, based on the temperature field analysis results, centrifugal load, torque load, and constraint boundary conditions are applied, and thermal-structural coupling analysis is performed to obtain the stress field change of each node over time, thereby determining the stress state information corresponding to each evaluation zone. The load cycle information can be statistically determined by using the cycle counting method based on the number of start-stop cycles, the number of load increases and decreases, and the corresponding stress amplitude changes for each operating condition.

[0048] In some other embodiments, temperature and stress can be quickly estimated by analytical calculation methods, thereby obtaining temperature history information and stress state information corresponding to each evaluation zone. For example, one-dimensional heat conduction analytical formula and elasticity analytical formula can be used to simplify the calculation of the key section of the rotor, or engineering empirical formulas can be used to quickly statistically analyze the load cycle. No specific limitations are made here.

[0049] S302, calculate the creep damage of each evaluation partition based on the temperature history information and stress state information of each evaluation partition; and calculate the low-cycle fatigue damage of each evaluation partition based on the load cycle information and stress state information of each evaluation partition.

[0050] Specifically, creep damage refers to the damage caused by slow plastic deformation that accumulates over time under the combined and sustained action of high temperature and stress. It is the sum of the damage accumulated in each high-temperature load-bearing segment of the region. By combining the temperature history and stress state information of each evaluation region with the high-temperature creep strength curves or creep fracture life curves of the material in that region at different temperatures and stress levels, the amount of creep damage accumulated in each operating period of the region can be calculated, representing the share of service life consumed by the high-temperature creep mechanism during the service life of that region.

[0051] For example, when calculating creep damage, the linear cumulative damage calculation method can be used, and its calculation expression can be expressed as: ; in, It represents the creep damage amount of the kth evaluation zone, which is a dimensionless cumulative damage value used to measure the share of creep life consumed by the high-temperature creep mechanism during the service of this zone. The duration of the i-th high-temperature load-preserving sub-segment is represented by the statistical analysis of the temperature history information corresponding to the evaluation partition, and the unit is hours. This represents the allowable service time of the material in the i-th high-temperature load-bearing segment of the evaluation partition under the corresponding temperature and equivalent stress conditions. It is obtained from the high-temperature creep strength curve or creep fracture life curve of the material in that partition at the corresponding temperature and stress level, and is expressed in hours. In the above formula, i is the sequence number of the high-temperature load-bearing segment, m is the total number of high-temperature load-bearing segments participating in the creep damage calculation within the evaluation partition, and the summation sign indicates that the damage share of all high-temperature load-bearing segments within the evaluation partition is accumulated.

[0052] Specifically, low-cycle fatigue damage refers to the damage that occurs when a material, under cyclic plastic deformation, develops cracks and propagates to fracture after a finite number of load cycles. It is the sum of the accumulated fatigue damage shares of a given region under each cycle category. Based on the load cycle information and stress state information of each evaluation region, combined with the low-cycle fatigue life curves of the material in that region under different temperature and strain amplitude conditions, the accumulated low-cycle fatigue damage of that region under each cycle category can be calculated to represent the share of service life consumed by the cyclic loading mechanism during the service life of that region.

[0053] For example, when calculating low-cycle fatigue damage, a linear cumulative damage calculation method can be used, and its calculation expression can be expressed as: ; in, It represents the low-cycle fatigue damage of the k-th evaluation zone, which is a dimensionless cumulative damage value used to measure the share of fatigue life consumed by the zone during service due to cyclic loading. This represents the actual number of cycles corresponding to the j-th type of load cycle, which is obtained by statistically counting all types of load cycles experienced by the evaluation partition throughout its entire service life, in units of cycles. This represents the allowable number of cycles corresponding to the j-th type of load cycle, i.e., the fatigue fracture life of the material in this evaluation zone under the corresponding temperature and strain amplitude conditions. It is obtained from the low-cycle fatigue life curve of the material in this zone at the corresponding temperature and strain amplitude, and the unit is cycles. In the above formula, j is the sequence number of the load cycle category, n is the total number of load cycle categories participating in the low-cycle fatigue damage calculation within this evaluation zone, and the summation sign indicates that the damage share of all load cycle categories within this evaluation zone is accumulated.

[0054] S303, calculate the creep-fatigue interactive damage of each evaluation partition based on the temperature history information, stress state information, load cycle information, creep damage, and low-cycle fatigue damage of each evaluation partition.

[0055] Furthermore, since the rotor is subjected to alternating high-temperature load and load cycles during peak operation and start-up / shutdown, there is an interactive effect of mutual acceleration between creep damage and fatigue damage. The damage generated by this interactive effect is often greater than the linear superposition of creep damage and fatigue damage. Therefore, in order to more accurately assess the true damage state of the rotor under interactive conditions, additional damage under creep-fatigue interaction can be calculated based on the temperature history information, stress state information, load cycle information, and the calculated creep damage and low-cycle fatigue damage of each assessment zone. This additional damage can then be quantified separately and incorporated into the damage assessment system.

[0056] For example, the creep-fatigue interaction diagram or interaction damage criterion corresponding to the material in the partition can be used to calculate the amount of creep-fatigue interaction damage in the partition under the current temperature and load cycle conditions. The specific process can be summarized as follows: First, determine the temperature and holding time of each high-temperature holding stage based on the temperature history information; determine the equivalent stress level borne by the corresponding stage based on the stress state information; and determine the cycle amplitude and number of cycles for the corresponding stage based on the load cycle information. Then, input the creep damage and low-cycle fatigue damage into the interaction diagram for interpolation to obtain the interaction damage amount, or substitute the creep damage, low-cycle fatigue damage, and load state parameters into the interaction damage criterion to calculate the interaction damage amount.

[0057] In some possible embodiments, when the evaluation partition does not meet the conditions of alternating high-temperature load and cyclic load, or when the material test data corresponding to the evaluation partition is insufficient to support the calculation of creep-fatigue interactive damage, creep-fatigue interactive damage may not be calculated. In subsequent steps, only creep damage and low-cycle fatigue damage are used to determine the control damage, and the reason for not calculating interactive damage is noted in the evaluation report.

[0058] S304, based on the creep damage, low-cycle fatigue damage and creep-fatigue interaction damage of each evaluation partition, determine the control damage of each evaluation partition, and use the control damage of each evaluation partition as the damage evaluation information of each evaluation partition.

[0059] It is understandable that the control damage for each assessment zone refers to the maximum damage value or equivalent damage value that plays a dominant role in controlling the safety margin of the zone among the three damage quantities—creep damage, low-cycle fatigue damage, and creep-fatigue interaction damage—that have been calculated for that zone. This value can serve as a comprehensive evaluation index of the current damage state of that zone. By solving for the creep damage, low-cycle fatigue damage, and creep-fatigue interaction damage quantities for each assessment zone according to steps S301-S303, the maximum value among the three can be taken as the control damage for that zone, or the equivalent damage value calculated using the creep-fatigue interaction criterion corresponding to the material of that zone can be used as the control damage. After obtaining the control damage for each assessment zone, this control damage can be used as the damage assessment information for each assessment zone, for subsequent steps to verify the zone correspondence with maintenance and inspection data.

[0060] S104, the damage assessment information of each assessment zone is checked against the maintenance and inspection data corresponding to each assessment zone, and the remaining life information of the turbine rotor to be assessed is determined based on the check results.

[0061] It is understandable that since damage assessment information is a theoretical assessment result obtained through finite element analysis and damage accumulation calculation based on operating data, design drawing information, and material performance data, while maintenance and inspection data is the measured state data obtained after on-site inspection of various parts of the rotor, the two types of data differ in source and nature. Therefore, after completing the damage calculation for each assessment zone of the rotor, the damage assessment information of each assessment zone can be checked against the corresponding maintenance and inspection data of each assessment zone to determine whether the theoretical calculation value matches the measured state and how to handle any discrepancies.

[0062] Here, the zone correspondence verification refers to comparing and judging the consistency of the controlled damage value calculated on each assessment zone with the inspection and testing results of the assessment zone at the same physical location. This comparison can verify the accuracy of the damage assessment information and thus discover the deviation that may be introduced by relying solely on calculation or the hidden damage that may be missed by relying solely on detection.

[0063] Specifically, when performing zonal verification of each assessment zone based on the damage assessment information of each assessment zone, the controlled damage of each assessment zone can be compared with the corresponding maintenance and testing data of each assessment zone. The calculated value of the controlled damage belonging to the same assessment zone and the maintenance and testing results such as the hardness test value, ultrasonic test rating, and metallographic structure rating of that zone are collected under that zone name. It is then determined whether the degree of damage reflected by the controlled damage is consistent with the actual measured state reflected by the maintenance and testing data, so as to determine the degree of matching between theoretical calculation and field measurement.

[0064] Here, when the damage level reflected by the damage control is higher than the preset damage threshold, but the actual measured state reflected by the maintenance and inspection data shows no abnormalities, it indicates that the calculated damage assessment result may be too conservative or the model boundary conditions may be too stringent. The actual material state of that rotor section has not yet reached the performance degradation level corresponding to this damage level. In this case, the completeness of the operating data and the calculation process data of temperature history, stress state, and load cycle information can be reviewed. Check whether the temperature boundary conditions are reasonable, whether the stress concentration factor is appropriate, and whether the material life curve matches the actual material state of the rotor. Based on the review results, determine whether to correct the temperature history, stress state, or load cycle information. If the review confirms that the operating data record is complete and the calculation process is correct, this section can be listed as a key tracking area, and re-inspection items can be added or the re-inspection cycle shortened in subsequent maintenance. If the review finds that the temperature boundary condition setting is too high or the stress concentration factor selection is too conservative, the corresponding temperature history, stress state, or load cycle information can be corrected based on the actual data found during the review.

[0065] The completeness of operational data refers to whether the steam temperature data, steam pressure data, unit load data, rotor speed data, start-up and shutdown time data, load increase / decrease process data, cumulative operating time data, and abnormal operation event record data corresponding to each operating condition section continuously cover the entire service period on the time axis, and whether the data are physically and logically consistent with each other. The calculation process data of stress state information and load cycle information is a complete record of the modeling parameters used in finite element analysis, such as mesh model, boundary conditions, load application methods, material constitutive parameters, and analysis step settings. By reviewing the above operational data and calculation process data, the specific causes of calculation deviations can be located, thereby determining whether corrections are needed and how to correct them.

[0066] Here, the preset damage threshold is a pre-set damage value used to determine whether the damage level of each assessment zone has reached the threshold requiring special attention or intervention. It can be comprehensively set based on the allowable damage limit determined by the high-temperature creep strength curve, low-cycle fatigue life curve, and creep-fatigue interaction diagram of the rotor material under corresponding service temperature and stress conditions, combined with the rotor's design life target and the manufacturer's technical specifications. For example, a creep fracture life consumption ratio of 0.5 or a low-cycle fatigue life consumption ratio of 0.7 corresponding to the rotor material at the service temperature can be used as a reference value for the preset damage threshold. Alternatively, the cumulative damage value corresponding to historical failure cases of rotors of the same type under similar service conditions can be used as a reference for the preset damage threshold. Furthermore, rotors with different material grades and different design life targets can have different preset damage threshold values, which can be individually calibrated based on the actual material performance data and design service life requirements of the rotor.

[0067] In contrast to the above situation, when the damage level reflected by the controlled damage is not higher than the preset damage threshold, but the measured state reflected by the maintenance and inspection data is abnormal, it indicates that the calculated damage assessment result may not fully reflect the actual degradation of the rotor in that section, and there are damage mechanisms or local abnormal factors that have not been included in the calculation. At this time, it is possible to check whether there are abnormal operating event records corresponding to the assessment section in the operating data, such as local overheating, water impact, or abnormal vibration that have occurred near the section but are not fully reflected in the regular operating records. It is also necessary to check whether the geometric structural features of the assessment section determined by the design drawings in the structural data accurately reflect the actual structure, such as whether there are local sharp corners or actual fillet radii smaller than the design value due to processing deviations in the section. Based on the verification results, it is necessary to determine whether to correct the geometric structural features of the assessment section or add the inspection data of the assessment section, so that the corrected calculation model can reflect the true geometric state and load conditions of the section.

[0068] It is understandable that, considering the uncertainties that may exist in the recording of operational data, the establishment of finite element models, and the selection of material parameters, when the degree of damage reflected by the control damage is inconsistent with the measured state reflected by the maintenance and inspection data, the verification results and the content to be corrected can be submitted to the user terminal for manual confirmation. Then, the user terminal can receive the corrected data for the verification results, and update the temperature history information, stress state information, and load cycle information based on the corrected data, so as to adjust the calculation input and re-evaluate the damage after obtaining new data or expert judgment.

[0069] Furthermore, after obtaining the updated temperature history, stress state, and load cycle information for each assessment zone, the remaining service life information of the turbine rotor to be assessed can be determined based on the verification results. This information can then guide the formulation of subsequent maintenance plans and operation control strategies. Here, the remaining service life information is the range of time or number of cycles within which the rotor can continue to serve safely, calculated based on the currently accumulated damage and the predetermined subsequent operating mode and load conditions. This information can serve as a quantitative basis for formulating maintenance plans, adjusting operating parameters, and assessing the feasibility of extending service life.

[0070] For example, when determining the remaining service life information, the control damage of each evaluation zone can be re-determined based on the updated temperature history information, stress state information, and load cycle information. That is, under the corrected calculation input conditions, the creep damage, low-cycle fatigue damage, and, if necessary, creep-fatigue interactive damage of each evaluation zone are recalculated, thereby obtaining the verified control damage of each evaluation zone, which serves as the final damage assessment result after verification by the test data. Then, based on the verified control damage of each evaluation zone and combined with the preset damage limit value, the remaining allowable service time or allowable number of cycles from the current state to reaching the damage limit of each evaluation zone can be determined, i.e., the remaining service life sub-information of each evaluation zone.

[0071] Thus, after obtaining the remaining life sub-information for each assessment zone, the remaining life information of the turbine rotor to be assessed can be determined based on the remaining life sub-information for each assessment zone. The shortest remaining life value in each zone is taken as the lower limit of the remaining life of the entire rotor, and the remaining life range is given according to the remaining life distribution of different zones. At this point, the minimum remaining life value of each assessment zone can be used as a conservative estimate of the remaining life of the entire rotor, or a weighted comprehensive method can be used to determine the remaining life assessment value of the entire rotor based on the damage status and importance of different zones.

[0072] In some possible embodiments, in order to provide users with more intuitive evaluation conclusions and directly serve subsequent maintenance and operation decisions, and to achieve a closed-loop process from damage calculation to maintenance measures, after obtaining the controlled damage of each evaluation zone after verification, refer to Figure 4 As shown, the process includes the following steps S401~S403: S401, based on the control damage of each of the assessment partitions after verification, determine the master control damage mechanism information and master control damage partition information of each of the assessment partitions.

[0073] It is understandable that the control damage in each assessment zone may originate from one or more of creep damage, low-cycle fatigue damage, or creep-fatigue interactive damage. Different damage mechanisms correspond to different subsequent operational control strategies and maintenance priorities. Therefore, when assessing the condition of each assessment zone, the dominant damage mechanism and dominant damage zone information for each assessment zone can be determined based on the damage type corresponding to the control damage in each zone. This means clarifying the dominant damage mechanism in each assessment zone and the location of the zone with the most severe damage across the entire rotor. For example, when the creep damage value of an assessment zone is significantly higher than the low-cycle fatigue damage value and interactive damage is not dominant, the dominant damage mechanism of that zone is creep damage. When an assessment zone is located in the impeller root transition zone and the control damage mainly originates from low-cycle fatigue damage accumulated during start-stop cycles, the dominant damage mechanism of that zone is low-cycle fatigue damage, and this zone is identified as the dominant damage zone.

[0074] S402, based on the control damage of each of the assessment zones after verification, determine the performance degradation level information of the turbine rotor to be assessed.

[0075] Specifically, based on the controlled damage values ​​of each assessment zone after verification and their relative relationship with the preset classification boundaries, the performance degradation level of the turbine rotor to be assessed can be determined. The performance degradation level information refers to the classification result used to qualitatively describe the current overall health level of the rotor. It is a status indicator of whether the rotor is suitable for continued operation and in what manner, and can include normal operation level, concern operation level, conditional operation level, and level where continued operation under current conditions is not recommended. For example, when the controlled damage of all assessment zones is at a low level and the maintenance and inspection data shows no abnormalities, it indicates that the overall condition of the rotor is good, and it can be determined as a normal operation level. Alternatively, when the controlled damage of a certain assessment zone is close to the preset classification boundary and the maintenance and inspection data of the corresponding part shows a decreasing trend in hardness or slight degradation of the metallographic structure, it indicates that the zone has entered a stage of accelerated damage development, and it can be determined as a concern operation level or conditional operation level.

[0076] Here, the preset grading boundary refers to the damage judgment standard that is pre-set to divide the boundaries between different performance degradation levels. It can be the control damage critical value corresponding to each level, or it can be a set of parameter threshold combinations used to define the judgment conditions of different levels. Specifically, it can be set according to the material performance data of the rotor, the historical state assessment data of rotors of the same type of unit, and the technical operation specifications provided by the manufacturer. No specific limitation is made here.

[0077] S403, based on the performance degradation level information, the main control damage mechanism information, and the main control damage partition information, generate subsequent operation suggestion information.

[0078] Furthermore, performance degradation level information can provide an overall assessment of the rotor's current operating state, serving as a macro-level basis for formulating subsequent operating strategies. The main control damage mechanism information and main control damage zone information represent the most critical damage types and the specific spatial locations of damage concentrations for the rotor. Based on the performance degradation level information and main control damage mechanism information, it is possible to determine which operating parameters require key control and which zones require key monitoring during subsequent operation, generating corresponding subsequent operating recommendations for different levels and mechanisms.

[0079] Specifically, subsequent operational recommendations can be generated based on different performance degradation levels or different main control damage mechanisms. These recommendations may include start-stop curve adjustment information, load increase / decrease rate limit information, steam temperature deviation control information, load range limit information, re-inspection cycle adjustment information, supplementary testing information, local treatment information, return-to-factory evaluation information, or replacement recommendations. The recommendations can be generated specifically based on the current performance degradation level and main control damage mechanism of the rotor, without any specific limitations here.

[0080] For example, when generating subsequent operational recommendations, the recommendations can be comprehensively determined based on the performance degradation level and the main control damage mechanism. When the performance degradation level is the normal operation level, the subsequent operational recommendations include information on operating according to the established operating mode and conducting scheduled re-inspections; when the performance degradation level is the concern operation level, the subsequent operational recommendations include information on identifying key tracking zones and shortening the re-inspection cycle; when the performance degradation level is the conditional operation level, the subsequent operational recommendations include information on limiting start-stop curves, limiting load increase / decrease rates, controlling steam temperature deviations, or limiting load ranges; when the performance degradation level is the level where continued operation under current conditions is not recommended, the subsequent operational recommendations include information on shutdown maintenance, return to plant assessment, localized treatment, parameter reduction operation assessment, or replacement. Meanwhile, the focus of the operational recommendations may vary depending on the main damage mechanism. When creep damage is dominant, the focus is on controlling the high-temperature holding time and steam temperature deviation. When low-cycle fatigue damage is dominant, the focus is on optimizing the start-stop curve and limiting the peak shaving amplitude. When creep-fatigue interactive damage is dominant, both high-temperature holding time and cyclic load intensity can be controlled simultaneously. When there are local defects, it is necessary to propose supplementary testing, local treatment, return to factory for evaluation, or replacement.

[0081] In this way, by completing the entire process from damage calculation to zonal verification and then to operation recommendations, the entire chain of steam turbine rotor condition quantitative assessment and maintenance strategy generation is achieved, which can better serve the power plant's maintenance decision-making and operation control.

[0082] The turbine rotor performance evaluation and life prediction method, apparatus, medium, and equipment provided in this disclosure divide the turbine rotor's operation process into multiple operating condition segments and divides the rotor into multiple evaluation zones based on structural and operational data. This achieves differentiated characterization of damage evolution in different regions of the rotor under specific operating stages, significantly improving the pertinence and accuracy of damage evaluation. Simultaneously, by verifying the damage evaluation information of each evaluation zone against the corresponding zone's actual maintenance and inspection data zone by zone, the deviation between theoretical calculations and engineering measurements can be effectively corrected, eliminating the cumulative error caused by a single global evaluation. This significantly improves the reliability and engineering credibility of the remaining life prediction results, helping to extend the rotor's service life while ensuring operational safety.

[0083] Those skilled in the art will understand that, in the above-described method of the specific implementation, the order in which each step is written does not imply a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of each step should be determined by its function and possible internal logic.

[0084] Based on the same inventive concept, this disclosure also provides a turbine rotor performance evaluation and life prediction device corresponding to the turbine rotor performance evaluation and life prediction method. Since the principle of the device in this disclosure for solving the problem is similar to the turbine rotor performance evaluation and life prediction method described above in this disclosure, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be described again.

[0085] Reference Figure 5 The diagram shown is a schematic of a turbine rotor performance evaluation and life prediction device 500 provided in an embodiment of this disclosure. The device includes: The data acquisition module 501 is used to acquire the evaluation dataset of the turbine rotor to be evaluated; wherein, the evaluation dataset includes structural data, operational data and maintenance and inspection data; The region division module 502 is used to divide the operation process of the turbine rotor to be evaluated into multiple operating condition segments based on the operation data; and to divide the turbine rotor to be evaluated into multiple evaluation zones based on the structural data and the operation data. The damage assessment module 503 is used to determine the damage assessment information of each assessment zone based on the operating data corresponding to each of the operating conditions. The lifespan determination module 504 is used to perform partition correspondence verification between the damage assessment information of each assessment partition and the maintenance and inspection data corresponding to each assessment partition, and determine the remaining lifespan information of the turbine rotor to be assessed based on the verification results.

[0086] In some possible embodiments, the structural data includes design drawings, material quality certificates, heat treatment records, factory mechanical performance records, factory non-destructive testing records, and maintenance records of the turbine rotor to be evaluated. The operational data includes steam temperature data, steam pressure data, unit load data, rotor speed data, start-up and shutdown time data, load increase and decrease process data, cumulative operating time data, and abnormal operation event record data of the turbine rotor to be evaluated during operation. The maintenance and testing data includes hardness test data, ultrasonic test data, phased array test data, magnetic particle test data, penetrant test data, metallographic test data, rotor bending amount test data, roundness test data, coaxiality test data, and vibration analysis data obtained during the maintenance of the turbine rotor to be evaluated after operation.

[0087] In some possible embodiments, the region division module 502 is specifically used for: Based on the design drawing information in the structural data, determine the journal area, disk or impeller transition area, geometric change area, shaft seal area, and area adjacent to the center hole or inner hole on the turbine rotor to be evaluated. Based on the design drawing information in the structural data and the steam temperature data in the operating data, the high-temperature steam action area on the turbine rotor to be evaluated is determined; Based on the maintenance records in the structural data, the historical abnormality areas on the turbine rotor to be evaluated are determined. Two or more of the journal region, the impeller or wheel transition region, the geometric change region, the shaft seal region, the region adjacent to the center hole or inner hole, the high-temperature steam action region, and the historical abnormality region are designated as the evaluation zones.

[0088] In some possible embodiments, the damage assessment module 503 is specifically used for: Based on the operating data corresponding to each operating condition segment, determine the temperature history information, stress state information, and load cycle information of each evaluation zone during operation; Based on the temperature history information and stress state information of each evaluation partition, the creep damage of each evaluation partition is calculated; and based on the load cycle information and stress state information of each evaluation partition, the low-cycle fatigue damage of each evaluation partition is calculated. Based on the temperature history information, stress state information, load cycle information, creep damage, and low-cycle fatigue damage of each evaluation zone, calculate the creep-fatigue interactive damage of each evaluation zone. Based on the creep damage, low-cycle fatigue damage, and creep-fatigue interaction damage of each evaluation partition, the control damage of each evaluation partition is determined, and the control damage of each evaluation partition is used as the damage evaluation information of each evaluation partition.

[0089] In some possible embodiments, the lifetime determination module 504 is specifically used for: The controlled damage of each evaluation zone is compared with the maintenance and inspection data corresponding to each evaluation zone to determine whether the degree of damage reflected by the controlled damage is consistent with the measured state reflected by the maintenance and inspection data. When the degree of damage reflected by the controlled damage is higher than the preset damage threshold, and no abnormality is found in the actual measured state reflected by the inspection and detection data, the integrity of the operating data and the calculation process data of the temperature history information, the stress state information and the load cycle information are reviewed, and it is determined whether to correct the temperature history information, the stress state information or the load cycle information based on the review results. When the degree of damage reflected by the controlled damage is not higher than the preset damage threshold, and the measured state reflected by the inspection and testing data is abnormal, check whether there is an abnormal operation event record in the operation data corresponding to the evaluation partition, and check whether the geometric structural features of the evaluation partition determined according to the design drawing information in the structural data accurately reflect the actual structure, and determine whether to correct the geometric structural features of the evaluation partition or add the detection data of the evaluation partition based on the verification results. When the degree of damage reflected by the controlled damage is inconsistent with the measured state reflected by the inspection and testing data, the system receives the correction data from the user terminal for the review results, and updates the temperature history information, the stress state information, and the load cycle information based on the correction data.

[0090] In some possible embodiments, the lifetime determination module 504 is specifically used for: Based on the updated temperature history information, stress state information and load cycle information, the control damage of each evaluation zone is re-determined to obtain the verified control damage of each evaluation zone. Based on the control impairment of each of the assessment partitions after verification, determine the remaining lifetime sub-information of each of the assessment partitions; The remaining life information of the turbine rotor to be evaluated is determined based on the remaining life sub-information of each evaluation partition.

[0091] In some possible embodiments, the lifetime determination module 504 is further configured to: Based on the control damage of each evaluation partition after verification, determine the main control damage mechanism information and main control damage partition information of each evaluation partition; Based on the control damage of each of the assessment zones after verification, the performance degradation level information of the turbine rotor to be assessed is determined; wherein, the performance degradation level information includes normal operation level, attention operation level, conditional operation level, and level that does not recommend continuing to operate under the current conditions; Based on the performance degradation level information, the main control damage mechanism information, and the main control damage zoning information, subsequent operation suggestions are generated; wherein, the subsequent operation suggestions include start-stop curve adjustment information, load increase / decrease rate limit information, steam temperature deviation control information, load range limit information, re-inspection cycle adjustment information, supplementary testing information, local treatment information, return-to-factory evaluation information, or replacement suggestion information.

[0092] Based on the same technical concept, this disclosure also provides a computer device. (See also...) Figure 6 The diagram shows the structure of a computer device 600 provided in this embodiment of the present disclosure, including a processor 601, a memory 602, and a bus 603. The memory 602 stores execution instructions and includes a main memory 6021 and an external memory 6022. The main memory 6021, also called internal memory, is used to temporarily store computational data in the processor 601 and data exchanged with external memory 6022 such as a hard disk. The processor 601 exchanges data with the external memory 6022 through the main memory 6021.

[0093] In this embodiment, the memory 602 is specifically used to store application code that executes the solution of this application, and its execution is controlled by the processor 601. That is, when the computer device 600 is running, the processor 601 communicates with the memory 602 through the bus 603, so that the processor 601 executes the application code stored in the memory 602, and then executes the method described in any of the foregoing embodiments.

[0094] The memory 602 may be, but is not limited to, random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc.

[0095] Processor 601 may be an integrated circuit chip with signal processing capabilities. The aforementioned processor can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it can also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this invention. The general-purpose processor can be a microprocessor or any conventional processor.

[0096] It is understood that the structures illustrated in the embodiments of this application do not constitute a specific limitation on the computer device 600. In other embodiments of this application, the computer device 600 may include more or fewer components than illustrated, or combine some components, or split some components, or have different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0097] This disclosure also provides a computer-readable storage medium storing a computer program. When executed by a processor, the computer program performs the steps of the turbine rotor performance evaluation and life prediction method described in the above-described method embodiments. The storage medium can be a volatile or non-volatile computer-readable storage medium.

[0098] This disclosure also provides a computer program product carrying program code. The program code includes instructions that can be used to execute the steps of the turbine rotor performance evaluation and life prediction method described in the above method embodiments. For details, please refer to the above method embodiments, which will not be repeated here.

[0099] The aforementioned computer program product can be implemented through hardware, software, or a combination thereof. In one optional embodiment, the computer program product is specifically embodied in a computer storage medium; in another optional embodiment, the computer program product is specifically embodied in a software product, such as a software development kit (SDK), etc.

[0100] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems and devices described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. In the several embodiments provided in this disclosure, it should be understood that the disclosed systems and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division; in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection may be through some communication interfaces; the indirect coupling or communication connection of devices or units may be electrical, mechanical, or other forms.

[0101] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0102] In addition, the functional units in the various embodiments of this disclosure can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0103] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this disclosure, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this disclosure. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0104] Finally, it should be noted that the above-described embodiments are merely specific implementations of this disclosure, used to illustrate the technical solutions of this disclosure, and not to limit them. The protection scope of this disclosure is not limited thereto. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features within the scope of the technology disclosed in this disclosure. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure, and should all be covered within the protection scope of this disclosure.

Claims

1. A method for evaluating the performance and predicting the lifespan of a steam turbine rotor, characterized in that, include: Obtain the evaluation dataset of the turbine rotor to be evaluated; wherein, the evaluation dataset includes structural data, operational data, and maintenance and inspection data; Based on the operational data, the operating process of the turbine rotor to be evaluated is divided into multiple operating condition segments; and based on the structural data and the operational data, the turbine rotor to be evaluated is divided into multiple evaluation zones. Based on the operating data corresponding to each of the aforementioned operating conditions, the damage assessment information for each of the aforementioned assessment zones is determined; The damage assessment information of each assessment zone is checked against the maintenance and inspection data corresponding to each assessment zone, and the remaining life information of the turbine rotor to be assessed is determined based on the check results.

2. The method according to claim 1, characterized in that, The structural data includes the design drawings, material quality certificates, heat treatment records, factory mechanical performance records, factory non-destructive testing records, and maintenance records of the turbine rotor to be evaluated. The operational data includes steam temperature data, steam pressure data, unit load data, rotor speed data, start-up and shutdown time data, load increase and decrease process data, cumulative operating time data, and abnormal operation event record data of the turbine rotor to be evaluated during operation. The maintenance and testing data includes hardness test data, ultrasonic test data, phased array test data, magnetic particle test data, penetrant test data, metallographic test data, rotor bending amount test data, roundness test data, coaxiality test data, and vibration analysis data obtained during the maintenance of the turbine rotor to be evaluated after operation.

3. The method according to claim 2, characterized in that, Based on the structural data and the operational data, the turbine rotor to be evaluated is divided into multiple evaluation zones, including: Based on the design drawing information in the structural data, determine the journal area, disk or impeller transition area, geometric change area, shaft seal area, and area adjacent to the center hole or inner hole on the turbine rotor to be evaluated. Based on the design drawing information in the structural data and the steam temperature data in the operating data, the high-temperature steam action area on the turbine rotor to be evaluated is determined; Based on the maintenance records in the structural data, the historical abnormality areas on the turbine rotor to be evaluated are determined. Two or more of the journal region, the impeller or wheel transition region, the geometric change region, the shaft seal region, the region adjacent to the center hole or inner hole, the high-temperature steam action region, and the historical abnormality region are designated as the evaluation zones.

4. The method according to claim 2, characterized in that, The determination of damage assessment information for each assessment zone includes: Based on the operating data corresponding to each operating condition segment, determine the temperature history information, stress state information, and load cycle information of each evaluation zone during operation; Based on the temperature history information and stress state information of each evaluation partition, the creep damage of each evaluation partition is calculated; and based on the load cycle information and stress state information of each evaluation partition, the low-cycle fatigue damage of each evaluation partition is calculated. Based on the temperature history information, stress state information, load cycle information, creep damage, and low-cycle fatigue damage of each evaluation zone, calculate the creep-fatigue interactive damage of each evaluation zone. Based on the creep damage, low-cycle fatigue damage, and creep-fatigue interaction damage of each evaluation partition, the control damage of each evaluation partition is determined, and the control damage of each evaluation partition is used as the damage evaluation information of each evaluation partition.

5. The method according to claim 4, characterized in that, The step of performing a partition-based verification between the damage assessment information of each assessment partition and the corresponding maintenance and inspection data of each assessment partition includes: The controlled damage of each evaluation zone is compared with the maintenance and inspection data corresponding to each evaluation zone to determine whether the degree of damage reflected by the controlled damage is consistent with the measured state reflected by the maintenance and inspection data. When the degree of damage reflected by the controlled damage is higher than the preset damage threshold, and no abnormality is found in the actual measured state reflected by the inspection and detection data, the integrity of the operating data and the calculation process data of the temperature history information, the stress state information and the load cycle information are reviewed, and it is determined whether to correct the temperature history information, the stress state information or the load cycle information based on the review results. When the degree of damage reflected by the controlled damage is not higher than the preset damage threshold, and the measured state reflected by the inspection and testing data is abnormal, check whether there is an abnormal operation event record in the operation data corresponding to the evaluation partition, and check whether the geometric structural features of the evaluation partition determined according to the design drawing information in the structural data accurately reflect the actual structure, and determine whether to correct the geometric structural features of the evaluation partition or add the detection data of the evaluation partition based on the verification results. When the degree of damage reflected by the controlled damage is inconsistent with the measured state reflected by the inspection and testing data, the system receives the correction data from the user terminal for the review results, and updates the temperature history information, the stress state information, and the load cycle information based on the correction data.

6. The method according to claim 5, characterized in that, The determination of the remaining life information of the turbine rotor to be evaluated based on the verification results includes: Based on the updated temperature history information, stress state information and load cycle information, the control damage of each evaluation zone is re-determined to obtain the verified control damage of each evaluation zone. Based on the control impairment of each of the assessment partitions after verification, determine the remaining lifetime sub-information of each of the assessment partitions; The remaining life information of the turbine rotor to be evaluated is determined based on the remaining life sub-information of each evaluation partition.

7. The method according to claim 6, characterized in that, After determining the remaining life information of the turbine rotor to be evaluated, the process includes: Based on the control damage of each of the assessment partitions after verification, determine the main control damage mechanism information and main control damage partition information of each assessment partition; Based on the control damage of each of the assessment zones after verification, the performance degradation level information of the turbine rotor to be assessed is determined; wherein, the performance degradation level information includes normal operation level, attention operation level, conditional operation level, and level that does not recommend continuing to operate under the current conditions; Based on the performance degradation level information, the main control damage mechanism information, and the main control damage zoning information, subsequent operation suggestions are generated; wherein, the subsequent operation suggestions include start-stop curve adjustment information, load increase / decrease rate limit information, steam temperature deviation control information, load range limit information, re-inspection cycle adjustment information, supplementary testing information, local treatment information, return-to-factory evaluation information, or replacement suggestion information.

8. A device for evaluating the performance and predicting the lifespan of a steam turbine rotor, characterized in that, include: The data acquisition module is used to acquire the evaluation dataset of the turbine rotor to be evaluated; wherein, the evaluation dataset includes structural data, operational data, and maintenance and inspection data; The region division module is used to divide the operating process of the turbine rotor to be evaluated into multiple operating condition segments based on the operating data; and to divide the turbine rotor to be evaluated into multiple evaluation zones based on the structural data and the operating data. The damage assessment module is used to determine the damage assessment information of each assessment zone based on the operating data corresponding to each of the operating conditions. The lifespan determination module is used to perform partition-based verification of the damage assessment information of each assessment partition with the maintenance and inspection data corresponding to each assessment partition, and determine the remaining lifespan information of the turbine rotor to be assessed based on the verification results.

9. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 1 to 7.

10. A computer device, comprising a storage medium, a processor, and a computer program stored on the storage medium and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method of any one of claims 1 to 7.

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