Indoor gas facility comprehensive degradation evaluation method based on multi-dimensional physical feature coupling

Abstract

The method for evaluating indoor gas facilities comprehensive deterioration based on multi-dimensional physical feature coupling solves the problems of single dimension, subjective and one-sided, insufficient quantification and lack of systematicness in evaluating the deterioration state of indoor gas facilities, and belongs to the technical field of gas safety monitoring and facility integrity management. The method comprises the following steps: collecting multi-dimensional physical feature data of indoor gas facilities, processing the data to obtain each sub-deterioration index; constructing a coupling weighting matrix model, calculating the dynamic equivalent weight after considering the mutual influence of each deterioration index based on the interaction coefficient matrix and combining the preset initial subjective weight, normalizing the dynamic equivalent weight to obtain the fusion weight, and then weighting and summing the fusion weight and each sub-deterioration index to obtain the facility deterioration comprehensive index; and generating the facility deterioration state evaluation result and the corresponding maintenance suggestion according to the facility deterioration comprehensive index and combining the preset grade division threshold.

Description

Technical Field

[0001] This invention relates to a comprehensive deterioration assessment method for indoor gas facilities based on multidimensional physical feature coupling, belonging to the technical field of gas safety monitoring and facility integrity management. Background Technology

[0002] Indoor gas facilities serve as the "last mile" of urban energy supply, and their long-term operational safety is crucial. During their service life, these facilities are subject to progressive deterioration due to various factors such as environmental corrosion, material aging, stress fatigue, and accidental damage, which are major causes of gas leaks, fires, and even explosions. Currently, the assessment of the deterioration of indoor gas facilities mainly relies on the following methods:

[0003] Regular visual inspections: Professionals periodically visit the facility to visually inspect for obvious rust, deformation, or signs of leakage (e.g., by applying soapy water). This method is subjective, inefficient, and cannot detect internal pipe corrosion, micro-cracks, or slow leaks at connections. Furthermore, the assessment results are difficult to quantify, record, and analyze for trends.

[0004] Single-parameter threshold alarm: For example, a household combustible gas alarm will only sound an alarm when the gas concentration accumulates to a set threshold. This is a "remedial" measure and cannot provide "pre-emptive warning" of the facility's own performance degradation (such as thinning of walls or aging of seals), nor can it locate the leak point or assess the degree of deterioration.

[0005] Isolated Applications of Advanced Testing Technologies: In certain specific scenarios or accident investigations, specialized equipment such as ultrasonic thickness measurement, infrared thermal imaging, and laser leak detection may be used. However, these technologies are often applied in isolation and unsystematically, resulting in fragmented test data. There is a lack of a unified framework to correlate and comprehensively evaluate the test results of different physical properties (mechanical, material, and sealing properties).

[0006] Qualitative judgment based on experience: The assessment clauses in current standards or specifications are mostly qualitative descriptions (such as severe corrosion, minor leakage), which rely on the personal experience of inspectors to determine the level. They lack objective and accurate quantitative standards, resulting in poor consistency of assessment results and making it difficult to support accurate maintenance decisions based on risk.

[0007] In summary, existing technologies for assessing the deterioration status of indoor gas facilities generally suffer from problems such as limited dimensions, subjective bias, insufficient quantification, and a lack of systematic comprehensiveness. This results in the inability to identify safety hazards early, comprehensively, and objectively, leaving safety management in a reactive mode for a long time. Summary of the Invention

[0008] To address the shortcomings of existing technologies in assessing the deterioration status of indoor gas facilities, such as limited dimensions, subjective bias, insufficient quantification, and lack of systematic integration, this invention provides a comprehensive deterioration assessment method for indoor gas facilities based on the coupling of multi-dimensional physical characteristics.

[0009] The present invention provides a comprehensive degradation assessment method for indoor gas facilities based on multi-dimensional physical characteristic coupling, comprising:

[0010] Collect multi-dimensional physical characteristic data of indoor gas facilities;

[0011] The collected multi-dimensional physical characteristic data is processed to obtain the degradation index of each component;

[0012] A coupled weighted matrix model is constructed to characterize the degree of mutual influence among the various deterioration indices. Based on the interaction coefficient matrix, the coupled weighted matrix model calculates the dynamic equivalent weight after considering the mutual influence of each deterioration index, and normalizes the dynamic equivalent weight to obtain the fusion weight. Then, the fusion weight is weighted and summed with each deterioration index to obtain the comprehensive facility deterioration index.

[0013] Based on the comprehensive facility deterioration index and the preset level classification thresholds, the facility deterioration status assessment results and corresponding maintenance recommendations are generated.

[0014] Preferably, the elements in the interaction coefficient matrix are , , The off-diagonal elements in the interaction coefficient matrix represent the number of individual degradation indices. It is a coefficient between [0, 1] that quantitatively represents the potential aggravating effect of the j-th degradation index on the evaluation result of the i-th degradation index.

[0015] As a preferred option, the deterioration indices include the material loss index, the structural deterioration index, and the sealing deterioration index.

[0016] As a preferred option, the material loss index is:

[0017]

[0018] in, and Let be the weight coefficient, and satisfy... , The average remaining wall thickness, For the original wall thickness, It represents the percentage of the remaining wall thickness at the thinnest point relative to the original wall thickness.

[0019] Preferably, pulse-echo ultrasonic measurement is used to measure the wall thickness at multiple measurement points of the indoor gas facility and calculate the average remaining wall thickness.

[0020] As a preferred option, the structural degradation index is:

[0021]

[0022] in, and These are the weighting coefficients. The vibration decay time constant, This is a reference value for the vibration decay time constant under healthy conditions. This refers to the main frequency offset.

[0023] As a preferred method, the vibration response of indoor gas facilities is measured using mechanical impedance analysis. The collected vibration response is then subjected to exponential fitting to obtain the vibration decay time constant. .

[0024] As a preferred option, the sealing degradation index is:

[0025]

[0026] in, , Indicates the initial pressure. Indicates the elapsed time The pressure afterwards.

[0027] As a preferred method, the segmented static pressure drop test method is used to measure the pressure change inside the indoor gas facility to obtain the initial pressure. and the duration The pressure after .

[0028] As a preferred option, the dynamic equivalent weight is:

[0029]

[0030] in, As the initial subjective weight, The interaction coefficient matrix, , , Material loss index Structural deterioration index and sealing degradation index The initial subjective weights;

[0031] right Normalization is performed to obtain the fusion weight vector. , , , Material loss index Structural deterioration index and sealing degradation index The fusion weight vector;

[0032] The comprehensive deterioration index of the facility is: ;

[0033] when The assessment result was that the facility's deterioration condition was excellent;

[0034] when The assessment result indicated that the facility was in good condition of deterioration.

[0035] when The assessment result indicates that the facility is in a state of deterioration and requires attention.

[0036] when The assessment result indicated that the facility was in poor condition.

[0037] when The assessment result indicated that the facility was in a dangerous state of deterioration.

[0038] The beneficial effects of this invention include: By conducting multi-dimensional physical parameter testing on indoor gas pipelines, valves, gas meters, connectors, and other facilities, and employing a coupled weighted matrix model for data fusion, this invention provides a systematic and quantitative comprehensive assessment of their deterioration status.

[0039] Comprehensive evaluation system: This invention constructs an evaluation system covering three core dimensions: "material loss, structural integrity and sealing performance". It overcomes the shortcomings of traditional methods that are one-sided and isolated, and can comprehensively and multi-dimensionally depict the health status of facilities.

[0040] The detection principle is reliable and the degree of quantification is high: This invention uses classic, proven physical detection methods from engineering practice as data sources. All evaluation inputs and outputs are precise physical quantities or standardized indices, completely eliminating reliance on subjective experience. The evaluation results are objective, repeatable, and traceable.

[0041] The model is scientifically advanced and reflects intrinsic connections: The coupled weighted matrix model proposed in this invention is the core innovation. It breaks through the assumption of independent weighting of indicators in traditional evaluation, scientifically simulates the real mutual influence and synergistic effects between different degradation modes, making the comprehensive evaluation results more in line with engineering practice, and greatly improving the accuracy and early warning value of the evaluation conclusions.

[0042] The implementation cost is controllable and the operation is highly feasible: the detection equipment required by this invention (ultrasonic thickness gauge, data acquisition device and accelerometer, precision pressure gauge) are all portable conventional instruments, requiring no permanent modification of facilities or installation of complex online monitoring systems. This method is particularly suitable for integration into regular professional inspection processes and is easy to promote and apply on a large scale in the gas industry.

[0043] The results are intuitive and clear, providing strong decision support: The FDCI output of this invention is a standardized, continuous, comprehensive score, facilitating horizontal comparisons of different facilities and vertical tracking of degradation trends for the same facility. The clear status levels and prominent sub-indices can directly guide the optimal allocation of maintenance resources, enabling a shift from "periodic maintenance" to "condition-based predictive maintenance," which has significant safety and economic value. Attached Figure Description

[0044] Figure 1 This is a flowchart of the method of the present invention;

[0045] Figure 2 This is a schematic diagram illustrating the principle of mechanical impedance analysis (impact test) in comprehensive degradation assessment.

[0046] Figure 3 This is a schematic diagram illustrating the principle of segmented voltage drop testing in comprehensive degradation assessment.

[0047] Figure 4 A schematic diagram illustrating the principle of calculating fusion weights for a coupled weighted matrix model;

[0048] Figure 5 This is a schematic diagram showing the correspondence between the Facility Deterioration Comprehensive Index (FDCI) and the condition level. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0051] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0052] This implementation proposes a three-layer evaluation technology scheme consisting of a "feature parameter layer, a sub-indicator layer, and a comprehensive index layer." Its core idea is to acquire multi-dimensional raw data from limited, field-implementable physical testing; transform the data into standardized sub-deterioration indicators reflecting different failure modes; and finally, through an innovative coupled weighted matrix model, simulate the mutual influence between the sub-indicators to obtain the final comprehensive evaluation result.

[0053] The comprehensive deterioration assessment method for indoor gas facilities based on multi-dimensional physical characteristic coupling in this embodiment includes:

[0054] S1. Multi-dimensional physical feature data acquisition

[0055] This layer uses three basic, complementary physical detection methods to obtain the raw characteristic parameters of the facility in three dimensions.

[0056] S101. Thickness Characteristic Parameter (T) Acquisition: Pulse-echo ultrasonic thickness measurement technology is used. The principle is that the longitudinal wave emitted by the ultrasonic probe propagates within the wall thickness of the facility, and is reflected upon encountering the other side of the material (inner wall or corrosion interface). By measuring the time interval between the emitted wave and the echo, combined with the sound velocity of the material, the wall thickness is calculated. N representative measurement points (usually evenly distributed and covering the suspected area) are selected on the surface of the facility to be evaluated (e.g., a pipe), and the remaining wall thickness value at each point is recorded. Calculate the average remaining wall thickness. The remaining wall thickness at the thinnest point and the original wall thickness percentage These represent the degree of uniform corrosion and localized pitting corrosion, respectively.

[0057] S102. Stiffness / Continuity Characteristic Parameter (S) Acquisition: Mechanical impedance analysis (impact test) was employed. The principle involves applying a transient excitation to the facility surface using a standard-mass impact hammer, while simultaneously acquiring the vibration response at that point using a high-sensitivity piezoelectric accelerometer. Structurally healthy facilities exhibit specific dynamic characteristics (“vibration fingerprints”). The acquired time-domain decay signal was subjected to exponential fitting to obtain the vibration decay time constant. This reflects the structural damping characteristics; internal corrosion or loose deposits can alter the damping. A Fast Fourier Transform (FFT) is performed on the signal to obtain the frequency response function, identifying its principal resonant frequency. Reference values ​​for a healthy state. Compare and calculate the decay time variation and the main frequency offset. Frequency shift is directly related to changes in structural stiffness and can be used to indirectly determine whether the overall wall thickness has been reduced or the connections have become loose.

[0058] S103. Acquisition of Sealing Characteristic Parameters (L): A segmented static pressure drop test method is used. The principle is based on the ideal gas law and flow conservation; within a closed volume, pressure drop is proportional to leakage. Isolation valves at both ends of the section of the facility to be evaluated (such as a pipeline section or a valve group) are closed to form a sealed test section. A precision pressure sensor is used to monitor the pressure change of the test gas (usually air or nitrogen) filling this section. The initial pressure after pressure stabilization is recorded. and after the prescribed time The pressure after Calculate the voltage drop rate per unit time. This value directly quantifies the overall leakage rate of the test section.

[0059] S2, Standardized Deterioration Index Calculation:

[0060] This step normalizes the physical parameters obtained in the previous step into a sub-degradation index within the range [0,1] using a preset transformation function. The larger the value, the more severe the degradation in that dimension.

[0061] S201, Material Loss Index calculate:

[0062]

[0063] in, and Let be the weight coefficient, and satisfy... .

[0064] The term characterizes the average corrosion depth. The most severe localized corrosion was characterized by this feature. By adjusting... It can flexibly reflect the degree of attention paid to uniform corrosion or pitting corrosion.

[0065] S202, Structural Deterioration Index calculate:

[0066]

[0067] in, and These are the weighting coefficients. This term ensures that it contributes a positive degradation value when the decay rate increases (damping increases, τ decreases), while the case where the decay rate decreases is not considered. The absolute value of the term reflects that any shift in frequency (usually decreasing) signifies a change in structural characteristics. This index comprehensively reflects changes in both structural stiffness and damping properties.

[0068] S203, Sealing Deterioration Index calculate:

[0069]

[0070] in, This is the maximum permissible pressure drop rate per unit time for this type of facility, determined based on relevant safety standards, specifications, or engineering experience. The formula normalizes the measured leakage rate; when the measured value exceeds the permissible threshold, the exponent reaches its maximum value of 1, indicating complete failure of the seal.

[0071] S3, Coupled Weighted Fusion and FDCI Calculation:

[0072] Considering that the degradation patterns of gas facilities are not independent, such as severe wall corrosion ( High height inevitably leads to a decrease in structural stiffness (impact) ), and greatly increase the risk of leakage (impact) A simple linear weighted average cannot capture this intrinsic relationship. Therefore, this implementation introduces a coupled weighted matrix model. Based on the interaction coefficient matrix, this coupled weighted matrix model calculates the dynamic equivalent weights after considering the mutual influence of each degradation index, and normalizes the dynamic equivalent weights to obtain the fusion weights. Then, the fusion weights are weighted and summed with each sub-degradation index to obtain the comprehensive facility degradation index.

[0073] S301. Define the interaction coefficient matrix. :

[0074] The elements in the interaction coefficient matrix are , , The off-diagonal elements in the interaction coefficient matrix represent the number of individual degradation indices. It is a coefficient between [0, 1], quantitatively representing the potential aggravating effect of the j-th degradation index on the evaluation result of the i-th degradation index. For S2, the interaction coefficient matrix of this embodiment... for:

[0075]

[0076] This is a 3x3 symmetric or asymmetric matrix. Diagonal elements are 1, representing the influence of an element on itself. Off-diagonal elements... It is a coefficient between [0,1] that quantitatively represents the potential aggravating effect of the j-th degradation on the assessment result of the i-th degradation. For example, This indicates that increased material loss will raise assessors' concerns about sealing risks by 40% (i.e., increase the weighting). These coefficients are determined based on statistical analysis of a large number of historical failure cases, accelerated aging test data in the laboratory, or domain expert knowledge.

[0077] Calculate the dynamic equivalent weight:

[0078] Suppose that the initial subjective weight vector set by the assessor based on facility type, importance, and experience is: ,and .

[0079] S302, Dynamic equivalent weight vector considering the mutual influence among degradation indicators The calculation is as follows:

[0080]

[0081] Then to After normalization, the fusion weight vector used for the final comprehensive calculation is obtained. :

[0082]

[0083] S303, Computing Facility Deterioration Index (FDCI):

[0084]

[0085] S4. Generation of assessment conclusions and maintenance recommendations: Based on the comprehensive facility deterioration index and the preset level classification threshold, generate the facility deterioration status assessment results and corresponding maintenance recommendations.

[0086] This step is the final output of the evaluation method in this implementation method. Its core function is to transform the calculated Facility Deterioration Comprehensive Index (FDCI), a quantitative result, into qualitative conclusions and graded maintenance strategies with clear engineering guidance significance.

[0087] The primary basis for drawing assessment conclusions is the determination of the FDCI value level. The value range is [0,1]. Based on a pre-set threshold, the facility status can be divided into multiple levels. This implementation sets the following five-level classification criteria:

[0088] excellent: The facility is in good condition and there is no significant risk of deterioration.

[0089] good: The facility exhibits slight deterioration, but its condition is stable and under control.

[0090] Notice: The facility shows clear signs of deterioration, requiring attention and enhanced monitoring.

[0091] bad: The facilities are in significant deterioration, posing increased safety risks and requiring planned intervention.

[0092] Danger: The facility is in a high-risk state, posing an immediate safety hazard, and requires immediate action.

[0093] Maintenance recommendations are generated based on the aforementioned level determination, combined with an assessment of the material loss index. Structural deterioration index Sealing deterioration index A comparative analysis was conducted. By identifying the dominant high-scoring indices, specific risk sources (such as primary sealing degradation or composite degradation of structure and materials) could be pinpointed, thereby generating targeted recommendations. The corresponding relationships are as follows:

[0094] Excellent / Good: It is recommended to implement "planned monitoring" and maintain routine inspections.

[0095] Attention Level: It is recommended to initiate a "preventive check" and conduct a special investigation on high-risk dimensions.

[0096] Defective level: It is recommended to develop a "corrective repair or replacement plan".

[0097] Danger level: It is recommended to trigger the "emergency shutdown and maintenance" procedure.

[0098] Finally, the system automatically generates a structured "Comprehensive Facility Deterioration Assessment Report." This structured report is the standardized final output document of this implementation method, systematically integrating all assessment data and intelligent analysis conclusions. The report includes: basic information such as the assessment object and conditions; quantitative calculation results of each sub-index and the Comprehensive Deterioration Index (FDCI); a five-level status conclusion from "Excellent" to "Hazardous" based on FDCI thresholds; analysis of the dominant risk sources identified through comparative sub-indices; and specific graded maintenance action recommendations from "Planned Monitoring" to "Emergency Response," generated based on status level and risk positioning. This report achieves a complete closed loop from multi-dimensional physical data collection and coupled model calculation to the generation of an authoritative technical document that can be directly used for safety management decisions, representing the ultimate value of the assessment method.

[0099] Example: This example uses a section of DN25 galvanized steel gas riser that has been in service for many years in the kitchen of a residential building as an example to conduct a comprehensive deterioration assessment of indoor galvanized steel gas risers;

[0100] Given: Original pipe wall thickness Health status reference vibration decay time constant The main resonant frequency The specification allows for a voltage drop rate threshold. .

[0101] 1. Feature parameter acquisition:

[0102] Wall thickness measurement: Using an ultrasonic thickness gauge, 15 points were evenly selected on the pipe for measurement. Result: The average wall thickness was calculated. Minimum wall thickness point Therefore .

[0103] Impact test: An accelerometer is installed in the middle of the pipe, and multiple impacts are performed with an impact hammer. The average signal value is recorded. The current decay time constant is then analyzed. main frequency .calculate .

[0104] Pressure drop test: Close the valves at both ends of the riser to form a closed section. Inflate with air to the required pressure. (Gauge pressure). After the pressure stabilizes, it drops to [a lower value] after 30 minutes. .calculate .

[0105] 2. Calculation of Sub-item Deterioration Index

[0106] Set weights: ; .

[0107]

[0108]

[0109]

[0110] 3. Calculation of the Composite Index FDCI (corresponding to) Figure 1 (S301-S303)

[0111] Set the initial weights and coupling matrix:

[0112] Given the severe consequences of pipeline seal failure, the highest initial weight is assigned to sealing performance. Let... .

[0113] Based on an engineering experience database, a coupling matrix for this type of pipeline is defined. for:

[0114]

[0115] Meaning: Material corrosion can significantly affect structural stiffness. ) and sealing risks ( Structural issues slightly increase the risk of leaks. Sealing and structural issues have no direct impact on material evaluation. The influence of structure on materials and sealing on structure is also set to 0.

[0116] Calculate the fusion weights:

[0117]

[0118] Normalized: Sum = 0.27 + 0.275 + 0.715 = 1.26.

[0119] .

[0120] It is evident that due to the coupled effects of material corrosion on sealing risk ( The final weight of sealing (0.568) is higher than the initial weight (0.55).

[0121] Calculate FDCI:

[0122]

[0123]

[0124] 4. Evaluation Conclusions and Recommendations

[0125] The calculated FDCI is 0.67. According to the status level classification (Excellent ≤ 0.2, Good ≤ 0.4, Caution ≤ 0.6, Poor ≤ 0.8, Dangerous > 0.8), this section of riser is at the "Poor" level, close to the "Danger" state, and immediate intervention measures are required.

[0126] The comprehensive assessment report points out:

[0127] Overall condition: FDCI=0.67, the facility is severely deteriorated and poses a high safety risk.

[0128] Main problem: Sealing deterioration index This indicates that there is a serious leak in the pipeline section, exceeding the allowable value of safety standards, which is the most pressing risk at present.

[0129] Secondary issue: Material loss index This indicates that the pipeline is significantly corroded, with an average wall thickness loss of approximately 15.6%, and there are localized severe corrosion spots (wall thickness loss of 37.5%).

[0130] Structural status: Structural degradation index This indicates that the pipe stiffness has decreased and the vibration characteristics have changed, which is consistent with material corrosion.

[0131] Maintenance Recommendations: ① Immediate Action: A thorough leak detection and repair of this pipe section must be carried out immediately to ensure a satisfactory seal. ② Planned Replacement: Given the severe corrosion and overall deterioration, it is recommended to plan and replace this section of riser as soon as possible. ③ Enhanced Monitoring: Before replacement, the inspection cycle should be shortened, and its condition should be closely monitored.

[0132] As can be seen from this embodiment, the present invention not only provides a quantitative overall risk score, but more importantly, it clearly reveals the composition of the risk and the main problem (sealing leakage), and quantifies the degree of secondary problems (corrosion). This assessment result provides a direct and reliable basis for formulating accurate, efficient, and economical maintenance strategies, fully demonstrating the practical value of the present invention.

[0133] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A comprehensive deterioration assessment method for indoor gas facilities based on multi-dimensional physical characteristic coupling, characterized in that, include: Collect multi-dimensional physical characteristic data of indoor gas facilities; The collected multi-dimensional physical characteristic data is processed to obtain the degradation index of each component; A coupled weighted matrix model is constructed to characterize the degree of mutual influence among the various deterioration indices. Based on the interaction coefficient matrix, the coupled weighted matrix model calculates the dynamic equivalent weight after considering the mutual influence of each deterioration index, and normalizes the dynamic equivalent weight to obtain the fusion weight. Then, the fusion weight is weighted and summed with each deterioration index to obtain the comprehensive facility deterioration index. Based on the comprehensive facility deterioration index and the preset level classification thresholds, the facility deterioration status assessment results and corresponding maintenance recommendations are generated.

2. The comprehensive deterioration assessment method for indoor gas facilities based on multi-dimensional physical characteristic coupling according to claim 1, characterized in that, The elements in the interaction coefficient matrix are , , The off-diagonal elements in the interaction coefficient matrix represent the number of individual degradation indices. It is a coefficient between [0, 1] that quantitatively represents the potential aggravating effect of the j-th degradation index on the evaluation result of the i-th degradation index.

3. The comprehensive deterioration assessment method for indoor gas facilities based on multi-dimensional physical characteristic coupling according to claim 1, characterized in that, The deterioration indices for each sub-item include the material loss index, the structural deterioration index, and the sealing deterioration index.

4. The comprehensive deterioration assessment method for indoor gas facilities based on multi-dimensional physical characteristic coupling according to claim 3, characterized in that, The material loss index is: in, and Let be the weight coefficient, and satisfy... , The average remaining wall thickness, For the original wall thickness, It represents the percentage of the remaining wall thickness at the thinnest point relative to the original wall thickness.

5. The comprehensive deterioration assessment method for indoor gas facilities based on multi-dimensional physical characteristic coupling according to claim 4, characterized in that, The wall thickness of indoor gas facilities at multiple measurement points was measured using pulse-echo ultrasonic technology, and the average remaining wall thickness was calculated.

6. The comprehensive deterioration assessment method for indoor gas facilities based on multi-dimensional physical characteristic coupling according to claim 3, characterized in that, The structural degradation index is: in, and These are the weighting coefficients. The vibration decay time constant, This is a reference value for the vibration decay time constant under healthy conditions. This refers to the main frequency offset.

7. The comprehensive deterioration assessment method for indoor gas facilities based on multi-dimensional physical characteristic coupling according to claim 6, characterized in that, The vibration response of indoor gas appliances was measured using mechanical impedance analysis. An exponential fit was performed on the collected vibration responses to obtain the vibration decay time constant. .

8. The comprehensive deterioration assessment method for indoor gas facilities based on multi-dimensional physical characteristic coupling according to claim 3, characterized in that, The seal deterioration index is: in, , Indicates the initial pressure. Indicates the elapsed time The pressure afterwards.

9. The comprehensive deterioration assessment method for indoor gas facilities based on multi-dimensional physical characteristic coupling according to claim 8, characterized in that, The pressure change inside the indoor gas facility was measured using a segmented static pressure drop test method to obtain the initial pressure. and the duration The pressure after .

10. The comprehensive deterioration assessment method for indoor gas facilities based on multi-dimensional physical feature coupling according to claim 9, characterized in that, The dynamic equivalent weight is: in, As the initial subjective weight, The interaction coefficient matrix, , , Material loss index Structural deterioration index and sealing degradation index The initial subjective weights; right Normalization is performed to obtain the fusion weight vector. , , , Material loss index Structural deterioration index and sealing degradation index The fusion weight vector; The comprehensive deterioration index of the facility is: ; when The assessment result was that the facility's deterioration condition was excellent; when The assessment result indicated that the facility was in good condition of deterioration. when The assessment result indicates that the facility is in a state of deterioration and requires attention. when The assessment result indicated that the facility was in poor condition. when The assessment result indicated that the facility was in a dangerous state of deterioration.

Images