Method, equipment, medium and product for evaluating corrosion degree of inner wall of metal water supply pipeline

Abstract

The invention discloses a metal water supply pipeline inner wall corrosion degree evaluation method, equipment, a medium and a product, and relates to the field of corrosion evaluation. The method comprises the following steps: firstly, acquiring lining types, pipe ages, water quality indexes and pipe wall corrosion degree score thresholds of a plurality of metal water supply pipeline samples; calculating the water body corrosion accumulation degree according to the pipe age and the water quality index of each metal water supply pipeline sample of the same lining type; function fitting is carried out on the water body corrosion accumulation degree and the pipe wall corrosion degree scoring threshold value of the multiple metal water supply pipeline samples of the same lining type, and a pipe wall corrosion degree scoring model under the lining type is obtained; during actual measurement, the target water body corrosion accumulation degree of the to-be-evaluated metal water supply pipeline is substituted into the pipe wall corrosion degree scoring model under the target lining type, a corresponding pipe wall corrosion degree score can be obtained through calculation, and then the inner wall corrosion degree is determined. The corrosion degree of the inner wall of the metal water supply pipeline can be efficiently and accurately measured under the condition that ground excavation is not needed.

Description

Technical Field

[0001] This application relates to the technical field of corrosion assessment, and particularly to a method, device, medium and product for assessing the corrosion degree of the inner wall of a metal water supply pipeline. Background Art

[0002] Urban water supply pipe networks are one of the most important infrastructure facilities in cities, and are a key area in current urban infrastructure construction, which are closely related to the daily life of urban residents. Ensuring the safety of urban water supply pipe networks is a major event related to people's health, social stability and economic development. With economic development and the continuous expansion of the urban scale, the demand for water is also increasing continuously, resulting in an increasing distance of water supply pipelines. With the continuous increase of newly built pipelines, the pipe age of the existing pipelines is also increasing, accompanied by the occurrence of aging and aggravated internal corrosion.

[0003] Since most water supply pipelines are made of metal, in addition to being easily corroded by the external soil, there will also be scaling / corrosion on the inner wall of the pipeline due to the difference in water supply quality, resulting in phenomena such as yellow water, turbid water and biofilm attachment. As an important material for water supply pipelines, metal pipes are prone to various actions such as oxidation corrosion, electrochemical reaction and bio-induced chemical erosion inside. The internal corrosion of water supply pipelines will not only cause the pipe wall to become thinner and perforated, poor compressive capacity or interface deformation, thus generating the risks of leakage and pipe burst, but also cause scaling on the inner wall, forming a "growth ring", reducing the hydraulic radius of the pipeline, and further affecting the water supply safety and stability. [[ID=??]]

[0004] Generally, the longer the pipe age, the more serious the corrosion degree of the inner wall of the pipeline, but there is no absolutely strong correlation between the two. The corrosion of the inner wall of the pipeline is also related to factors such as the quality of the water leaving the factory, the pipe wall lining, the pipe material and the operating conditions. Currently, for the definition of old pipelines, the industry usually takes the pipe age of 50 years and above as a condition, and will pay special attention to such pipelines and take measures such as excavation and repair or direct replacement of the pipeline. However, this "one-size-fits-all" method has the following disadvantages. On the one hand, directly carrying out excavation and repair or pipe replacement measures based on the pipe age has extremely high uncertainty. According to the previous detection results, it is found that there is no obvious corrosion inside some pipelines with a pipe age of 50 years. If direct excavation and repair or pipe replacement measures are taken for them, not only will the investment in manpower and material resources be huge, but it will also cause a large-scale water cut-off impact. On the other hand, simply taking 50 years as the judgment basis for old and severely corroded pipelines will lead to omissions. For example, although the pipe age of some pipelines is less than 50 years, due to reasons such as production process, pipe material and water quality of water transmission and distribution, there may also be serious internal corrosion. Summary of the Invention

[0005] In view of the problems pointed out in the background art, the present application provides a method, device, medium and product for evaluating the corrosion degree of the inner wall of a metal water supply pipe, which can efficiently and accurately determine the corrosion degree of the inner wall of a metal water supply pipe without ground excavation.

[0006] To achieve the above object, the present application provides the following solutions.

[0007] In a first aspect, the present application provides a method for evaluating the corrosion degree of the inner wall of a metal water supply pipe, including:

[0008] Obtain the lining type, pipe age, water quality index and wall corrosion degree scoring threshold of multiple metal water supply pipe samples;

[0009] Calculate the cumulative degree of water body corrosion of each metal water supply pipe sample according to the pipe age and water quality index of each metal water supply pipe sample of the same lining type;

[0010] Perform function fitting on the cumulative degree of water body corrosion and the wall corrosion degree scoring threshold of multiple metal water supply pipe samples of the same lining type to obtain a wall corrosion degree scoring model under this lining type;

[0011] Obtain the target lining type, target pipe age and target water quality index of the metal water supply pipe to be evaluated;

[0012] Calculate the target cumulative degree of water body corrosion of the metal water supply pipe to be evaluated according to the target pipe age and target water quality index;

[0013] Substitute the target cumulative degree of water body corrosion into the wall corrosion degree scoring model under the target lining type to calculate the wall corrosion degree score of the metal water supply pipe to be evaluated;

[0014] Determine the corrosion degree of the inner wall of the metal water supply pipe to be evaluated according to the wall corrosion degree score of the metal water supply pipe to be evaluated.

[0015] Optionally, the lining types of the multiple metal water supply pipe samples include no lining, cement lining and epoxy resin lining; the water quality indexes include the Langelier saturation index and the Larson ratio.

[0016] Optionally, the calculating the cumulative degree of water body corrosion of each metal water supply pipe sample according to the pipe age and water quality index of each metal water supply pipe sample of the same lining type specifically includes:

[0017] For the nth metal water supply pipe sample of the same lining type, based on the Langelier saturation index LSI n and the Larson ratio LR n , by looking up the water quality corrosion potential scoring table, determine LSIn and LR n corresponding water quality corrosion potential score and where n = 1, 2,..., N; N is the number of metal water supply pipe samples under the same lining type;

[0018] Using the formula Calculate the cumulative degree of water body corrosion X of the nth metal water supply pipe sample n ; where CT n is the pipe age of the nth metal water supply pipe sample.

[0019] Optionally, the cumulative degree of water body corrosion and the scoring threshold of the pipe wall corrosion degree of multiple metal water supply pipe samples of the same lining type are fitted by a function to obtain the pipe wall corrosion degree scoring model under this lining type, specifically including:

[0020] For N metal water supply pipe samples of the same lining type, the cumulative degree of water body corrosion X of the nth metal water supply pipe sample n is used as the independent variable, and the scoring threshold Y of the pipe wall corrosion degree of the nth metal water supply pipe sample n is used as the dependent variable, and multiple functions such as linear fitting function, quadratic fitting function, logarithmic fitting function, exponential fitting function, locally weighted regression function, logistic fitting function, piecewise fitting function and power function are used for fitting respectively, and the function relationship with the correlation coefficient R 2 > 0.9 and the highest is selected as the pipe wall corrosion degree scoring model under this lining type.

[0021] Optionally, when the lining type of multiple metal water supply pipe samples is no lining, the pipe wall corrosion degree scoring model under no lining protection is Y = 0.01904*X - 0.2348; where X represents the cumulative degree of water body corrosion; Y represents the pipe wall corrosion degree score.

[0022] Optionally, when the lining type of multiple metal water supply pipe samples is cement lining, the pipe wall corrosion degree scoring model under cement lining protection is Y = -8.879e -5 *X 2 + 0.03699*X - 0.5362; where X represents the cumulative degree of water body corrosion; Y represents the pipe wall corrosion degree score.

[0023] Optionally, the method for determining the inner wall corrosion degree of the metal water supply pipe to be evaluated according to the pipe wall corrosion degree score of the metal water supply pipe to be evaluated specifically includes:

[0024] When the pipe wall corrosion degree score of the metal water supply pipe to be evaluated is between 0 and 1, it is determined that the inner wall corrosion degree of the metal water supply pipe to be evaluated is basically intact;

[0025] When the wall corrosion degree score of the metal water supply pipe to be evaluated is between 1 and 2, it is determined that the inner wall corrosion degree of the metal water supply pipe to be evaluated is mild corrosion;

[0026] When the wall corrosion degree score of the metal water supply pipe to be evaluated is between 2 and 3, it is determined that the inner wall corrosion degree of the metal water supply pipe to be evaluated is medium corrosion;

[0027] When the wall corrosion degree score of the metal water supply pipe to be evaluated is greater than 3, it is determined that the inner wall corrosion degree of the metal water supply pipe to be evaluated is severe corrosion.

[0028] In a second aspect, the present application provides a computer device, including: a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor executes the computer program to implement the method for evaluating the inner wall corrosion degree of the metal water supply pipe.

[0029] In a third aspect, the present application provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the method for evaluating the inner wall corrosion degree of the metal water supply pipe.

[0030] In a fourth aspect, the present application provides a computer program product, including a computer program, and when the computer program is executed by a processor, it implements the method for evaluating the inner wall corrosion degree of the metal water supply pipe.

[0031] According to the specific embodiments provided by the present application, the following technical effects are disclosed.

[0032] A method, device, medium, and product for evaluating the inner wall corrosion degree of a metal water supply pipe provided by the present application comprehensively consider various factors such as the water quality index of the water supply network, pipe age, and lining type, and predict the inner wall corrosion degree of the metal water supply pipe through a non-excavation approach. On the one hand, it can avoid the high-cost investment and water cut-off impact of directly large-scale excavating and inspecting the inner pipe, and on the other hand, it realizes the efficient and accurate determination of the inner wall corrosion degree of metal water supply pipes with different lining types, and can provide a scientific and accurate reference basis for the renovation and planning of old pipelines. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application, and those of ordinary skill in the art can also obtain other drawings based on these drawings without creative efforts.

[0034] Figure 1 It is a schematic flowchart of a method for evaluating the inner wall corrosion degree of a metal water supply pipe according to the present application;

[0035] Figure 2 It is a schematic diagram of the corrosion condition of the inner wall of a metal water supply pipe with a cement lining in the embodiment of the present application;

[0036] Figure 3 It is a schematic diagram of the corrosion condition of the inner wall of a metal water supply pipe without lining protection in the embodiment of the present application;

[0037] Figure 4 It is a schematic diagram of the water body corrosion potential score calculated for the water body flowing through metal water supply pipe samples with different lining types in the embodiment of the present application;

[0038] Figure 5 It is a schematic diagram of the fitting model between the corrosion degree score of the metal water supply pipe wall under the protection of the cement lining and the cumulative degree of water body corrosion in the embodiment of the present application;

[0039] Figure 6 It is a schematic diagram of the fitting model between the corrosion degree score of the metal water supply pipe wall without lining protection and the cumulative degree of water body corrosion in the embodiment of the present application. Detailed implementation manners

[0040] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0041] Based on the pipe age, water quality index, and lining characteristics of the water supply pipe, the present application proposes a method, device, medium, and product for evaluating the corrosion degree of the inner wall of a metal water supply pipe, aiming to efficiently and accurately measure the corrosion degree of the inner wall of the metal water supply pipe without implementing ground excavation.

[0042] To make the above objects, features, and advantages of the present application more obvious and understandable, the present application will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0043] In an exemplary embodiment, as Figure 1 shown, a method for evaluating the corrosion degree of the inner wall of a metal water supply pipe is provided, including the following steps 1 to 7.

[0044] Step 1: Obtain the lining type, pipe age, water quality index, and the scoring threshold of the pipe wall corrosion degree of multiple metal water supply pipe samples.

[0045] In the data collection stage, on the one hand, multiple metal water supply pipeline samples are collected for the target area, and the lining types, pipe ages, and water quality indices of the multiple metal water supply pipeline samples are counted. Among them, the materials of the multiple metal water supply pipeline samples include cast iron, ductile iron, and steel. The lining (coating) types of the multiple metal water supply pipeline samples include no lining, cement lining, epoxy resin lining, etc. The pipe age refers to the buried pipe age, that is, the corrosion time of the metal water supply pipeline underground. The water quality indices include the Langelier saturation index and the Larson ratio.

[0046] The process of measuring the water quality index of a metal water supply pipeline (hereinafter also referred to as a water supply pipeline or pipeline) is as follows. Collect a water flow sample flowing through the metal water supply pipeline, and measure the pH value, TDS (Total Dissolved Solids, the total amount of dissolved solids in water), CaCO3 concentration (mg / L), temperature T (°C), Cl - concentration (mol / L), SO4 2- concentration (mol / L), and HCO3 - concentration (mol / L) of the water sample. According to the calculation formula (1) of the Langelier saturation index, measure the Langelier saturation index (Langelier Saturation Index, LSI) of the metal water supply pipeline:

[0047] LSI = pH - pH s (1)

[0048] Among them,

[0049] pH s = 9.3 + N s + N t - N h - N a (2)

[0050] In the formula, LSI is the specific value of the calculated Langelier saturation index; pH is the pH value of the water sample; N s is the dissolved solid constant corresponding to TDS; N t is the temperature constant corresponding to the temperature T (°C) of the water sample; N h is the calcium hardness constant, calculated as CaCO3 (mg / L); N a is the total alkalinity constant, calculated as CaCO3 (mg / L).

[0051] According to the calculation formula (3) of the Larson ratio, measure the Larson ratio (LR) of the metal water supply pipeline:

[0052] LR = ([Cl - +[SO4 2-) / [HCO3 - (3)

[0053] where LR is the specific value of the calculated Larson ratio; [Cl - , [SO4 2- , and [HCO3 - represent the concentrations of Cl - (mol / L), SO4 2- (mol / L), and HCO3 - (mol / L), respectively.

[0054] On the other hand, the corrosion degree of the pipe wall of each metal water supply pipe sample is classified, and the corresponding scoring threshold of the pipe wall corrosion degree is determined. The pipe wall corrosion degree in this application refers to the corrosion degree of the inner wall of the pipe. The correspondence between the pipe wall (inner wall) corrosion degree and the pipe wall corrosion degree scoring threshold is shown in Table 1 below.

[0055] Table 1 Correspondence table of pipe wall corrosion degree and pipe wall corrosion degree scoring threshold

[0056] Degree of pipe wall corrosion Scoring threshold for degree of pipe wall corrosion Basically intact [0,1) Mild corrosion [1,2) Moderate corrosion [2,3) Severe corrosion [3,∞)

[0057] That is to say, according to the corrosion status of multiple metal water supply pipe samples in this application, the pipe wall corrosion degree is divided into four grades: basically intact, slightly corroded, moderately corroded, and severely corroded, and the corresponding pipe wall corrosion degree scoring thresholds for each grade are determined, namely {0, 1, 2, 3}. On this basis, methods such as expert experience method or experimental determination are used to determine the corresponding pipe wall corrosion degree scoring threshold for the actual corrosion condition of the inner wall of each metal water supply pipe sample. For example, for the nth metal water supply pipe sample of the same lining type, if it is determined that its inner wall is basically intact, then the corresponding pipe wall corrosion degree scoring threshold Y n = 0; if it is determined that its inner wall has reached a slightly corroded degree, then Y n = 1; if it is determined that its inner wall has reached a moderately corroded degree, then Y n = 2; if it is determined that its inner wall has reached a severely corroded degree, then Y n = 3.

[0058] Step 2: Calculate the cumulative degree of water body corrosion of each metal water supply pipe sample according to the pipe age and water quality index of each metal water supply pipe sample of the same lining type.

[0059] The cumulative degree of water body corrosion in this application is the product of the water body corrosion potential score and the pipe age (corrosion time), and the water body corrosion potential score is the sum of the water quality corrosion potential scores of the Langelier saturation index and the Larson ratio.

[0060] Specifically, for the nth metal water supply pipe sample of the same lining type, based on the Langelier saturation index LSI of the nth metal water supply pipe sample n and the Larson ratio LR n , by looking up the water quality corrosion potential scoring table, as shown in Table 2 below, determine the water quality corrosion potential scores corresponding to LSI n and LR n , and where n = 1, 2,..., N; N is the number of metal water supply pipe samples of the same lining type.

[0061] Table 2 Water Quality Corrosion Potential Scoring Table Based on Water Quality Index

[0062] Langeliar index Larsen ratio Scoring of water quality corrosion potential ≥0 ≤0.5 0 -0.25～0 0.5～1.0 1 -0.5～-0.25 1.0～1.5 2 -0.75～-0.5 1.5～2.0 3 -1～-0.75 2.0～3.0 4 ≤-1 ≥3.0 5

[0063] Furthermore, use formula (4) to calculate the cumulative degree of water body corrosion X of the nth metal water supply pipe sample n :

[0064]

[0065] where CT n is the pipe age of the nth metal water supply pipe sample.

[0066] For example, assume that the Langelier saturation index LSI of the nth metal water supply pipe sample measured n is -0.3, within the range of -0.5 to -0.25, then determine the water quality corrosion potential score corresponding to LSI n is 2. At the same time, assume that the Larson ratio LR of the nth metal water supply pipe sample measured is 0.6, within the range of 0.5 to 1.0, then determine the water quality corrosion potential score corresponding to LR n is 1. At this time, for the nth metal water supply pipe sample n Then multiply the water body corrosion potential score (= 3) by the pipe age CT The product is the current cumulative degree of water body corrosion X . n n .

[0067] Step 3: Perform function fitting on the cumulative degree of water body corrosion and the scoring threshold of pipe wall corrosion degree of multiple metal water supply pipe samples of the same lining type to obtain the pipe wall corrosion degree scoring model under this lining type.

[0068] For the N metal water supply pipe samples of the same lining type, take the cumulative degree of water body corrosion X of the nth metal water supply pipe sample n ​Taking the corrosion degree scoring threshold Y of the nth metal water supply pipeline sample as the independent variable n ∈{0,1,2,3} as the dependent variable, various functions such as linear fitting function, quadratic fitting function, logarithmic fitting function, exponential fitting function, locally weighted regression function, logistic fitting function, piecewise fitting function and power function are used for fitting respectively, and the correlation coefficient R 2 >0.9 and R 2 The highest functional relationship is used as the scoring model for the corrosion degree of the pipe wall under this lining type.

[0069] Specifically, the cumulative degree of water body corrosion X n and the corrosion degree scoring threshold Y of the pipe wall n are fitted by using the Matlab curve fitting toolbox cftool, and the functional relationships with the correlation coefficient R 2 >0.9 are screened to determine the range of the highest degree of the polynomial equation. In order to simplify the scoring model as much as possible and conform to the changing law of actual pipeline corrosion, within the range where the correlation coefficient changes slightly, for example, when R 2 ≤2%, a low-degree equation is selected for fitting, and GraphPadPrism 9.0 is used for verification calculation and image visualization. The data samples in the fitting process are obtained by comprehensively calculating a large number of samples collected and detected under different lining types, different pipe ages and different water quality conditions in the target area. During the fitting process, various modeling methods are tried, and the functional relationship with the correlation R 2 >0.9 and the highest is determined as the optimal functional relationship to be used, and the optimal functional relationship is saved as the scoring model for the corrosion degree of the pipe wall under the corresponding lining type for subsequent use.

[0070] In an exemplary embodiment, the lining type of the metal water supply pipeline sample is only cement lining or no lining. The optimal functional relationship between the corrosion degree scoring of the pipe wall protected by cement lining and the cumulative degree of water body corrosion obtained by fitting with various functions is:

[0071] Y = -8.879e -5 *X 2 +0.03699*X - 0.5362 (5)

[0072] where X represents the cumulative degree of water body corrosion; Y represents the corrosion degree scoring of the pipe wall. The R 2 of the functional relationship (5) is 0.9121, so the functional relationship (5) is saved as the scoring model for the corrosion degree of the pipe wall protected by cement lining.

[0073] The optimal functional relationship between the corrosion degree scoring of the pipe wall without lining protection and the cumulative degree of water body corrosion obtained by fitting with various functions is:

[0074] Y = 0.01904*X - 0.2348 (6)

[0075] For the function (6), the R 2 = 0.9352, then the function (6) is saved as the scoring model for the corrosion degree of the pipe wall without internal lining protection.

[0076] Step 4: Obtain the target lining type, target pipe age, and target water quality index of the metal water supply pipe to be evaluated.

[0077] After completing the data fitting of the scoring model for the corrosion degree of the pipe wall, it can be used for real-time, continuous, and non-excavation evaluation of the corrosion degree of the inner wall of the metal water supply pipe. Specifically, for the metal water supply pipe to be evaluated in the target area, obtain its corresponding lining type, pipe age, and water quality index (including Langelier saturation index and Larson ratio). To distinguish them from the lining type, pipe age, and water quality index of the metal water supply pipe sample, they are called the target lining type, target pipe age, and target water quality index.

[0078] Step 5: Calculate the target cumulative degree of water body corrosion of the metal water supply pipe to be evaluated according to the target pipe age and target water quality index.

[0079] The cumulative degree of water body corrosion is the product of the water body corrosion potential score and the pipe age (corrosion time). The water body corrosion potential score is obtained by adding the water quality corrosion potential scores of the Langelier saturation index and the Larson ratio. Specifically, the target cumulative degree of water body corrosion of the metal water supply pipe to be evaluated can be calculated with reference to the above formula (4).

[0080] Step 6: Substitute the target cumulative degree of water body corrosion into the scoring model for the corrosion degree of the pipe wall under the target lining type, and calculate the scoring of the corrosion degree of the pipe wall of the metal water supply pipe to be evaluated.

[0081] Substitute the target cumulative degree of water body corrosion into X in the scoring model for the corrosion degree of the pipe wall under the target lining type, and the scoring Y of the corrosion degree of the pipe wall of the metal water supply pipe to be evaluated can be directly calculated.

[0082] Step 7: Determine the corrosion degree of the inner wall of the metal water supply pipe to be evaluated according to the scoring of the corrosion degree of the pipe wall of the metal water supply pipe to be evaluated.

[0083] According to the scoring of the pipe wall corrosion degree, a comprehensive evaluation of the inner wall corrosion degree of the metal water supply pipe to be evaluated can be made. The evaluation results are divided into basically intact, slightly corroded, moderately corroded, and severely corroded. Specifically, when the scoring of the pipe wall corrosion degree of the metal water supply pipe to be evaluated is between 0 and 1, it is determined that the inner wall corrosion degree of the metal water supply pipe to be evaluated is basically intact; when the scoring of the pipe wall corrosion degree of the metal water supply pipe to be evaluated is between 1 and 2, it is determined that the inner wall corrosion degree of the metal water supply pipe to be evaluated is slightly corroded; when the scoring of the pipe wall corrosion degree of the metal water supply pipe to be evaluated is between 2 and 3, it is determined that the inner wall corrosion degree of the metal water supply pipe to be evaluated is moderately corroded; when the scoring of the pipe wall corrosion degree of the metal water supply pipe to be evaluated is greater than 3, it is determined that the inner wall corrosion degree of the metal water supply pipe to be evaluated is severely corroded.

[0084] The purpose of this application is to evaluate the inner wall corrosion degree of metal water supply pipes. By establishing an evaluation model for the inner wall corrosion degree of metal water supply pipes based on the water quality of the pipe network and the pipe age, a method for preliminarily evaluating the internal corrosion degree of water supply pipes based on the water quality index and pipe age inside the pipes is formed, providing a basis for the preliminary screening and prediction of the corrosion state of old pipes. During the maintenance of the urban water supply pipe network, when the scoring of the pipe wall corrosion degree reaches 2 or more, it enters the maintenance strategy stage; when the scoring of the pipe wall corrosion degree reaches 3 or more, it indicates that the inner wall is severely corroded and is treated according to the retirement strategy.

[0085] In an exemplary embodiment, the corresponding relationships among the cumulative degree of water body corrosion, the scoring of the pipe wall corrosion degree, and the inner wall corrosion degree of the metal water supply pipe protected by cement lining are shown in Table 3 below.

[0086] Table 3 Corresponding table of the cumulative degree of water body corrosion, the scoring of the pipe wall corrosion degree, and the inner wall corrosion degree when there is cement lining

[0087] Degree of water body corrosion accumulation Scoring of degree of pipe wall corrosion Degree of inner wall corrosion 0-48.18 0-1 Basically intact 48.18-88.40 1-2 Mild corrosion 88.40-152.50 2-3 Moderate corrosion ＞152.50 ＞3 Severe corrosion

[0088] In an exemplary embodiment, the corresponding relationships among the cumulative degree of water body corrosion, the scoring of the pipe wall corrosion degree, and the inner wall corrosion degree of the metal water supply pipe without lining protection are shown in Table 4 below.

[0089] Table 4 Corresponding table of the cumulative degree of water body corrosion, the scoring of the pipe wall corrosion degree, and the inner wall corrosion degree when there is no lining

[0090] Degree of water body corrosion accumulation Scoring of degree of pipe wall corrosion Degree of inner wall corrosion 0-64.85 0-1 Basically intact 64.85-117.37 1-2 Mild corrosion 117.37-169.89 2-3 Moderate corrosion ＞169.89 ＞3 Severe corrosion

[0091] In actual use, first calculate the pipe wall corrosion degree score according to the pipe wall corrosion degree scoring model under the target lining type, and then qualitatively evaluate the inner wall corrosion degree according to the corresponding scoring range in Table 3 or Table 4, such as basically intact, slightly corroded, etc. The pipe wall corrosion degree scoring models under different lining types are mainly used to qualitatively evaluate the pipe wall (inner wall) corrosion degree according to a unified score range when scoring the pipe wall corrosion degree, which is convenient to form a unified evaluation standard for the inner wall corrosion degree under different lining types, different water qualities and pipe ages.

[0092] At present, the research on the inner wall corrosion degree of metal water supply pipes has not been associated with the water quality indexes in the pipes. Therefore, the current research has not involved the evaluation model of the inner wall corrosion degree of metal water supply pipes associated with the water quality indexes and pipe ages in the pipes. This application first directly evaluates the inner wall corrosion degree of metal water supply pipes by using the pipe network water quality indexes and pipe ages, associates the inner wall corrosion degree of metal water supply pipes with the characteristic water quality indexes and pipe ages, and establishes an evaluation model for the inner wall corrosion degree of metal water supply pipes based on the pipe network water quality and pipe ages, that is, the pipe wall corrosion degree scoring model. A method for preliminarily evaluating the internal corrosion degree of water supply pipes based on the water quality indexes (Langelier saturation index and Larson ratio) and pipe ages in the pipes is formed, which provides a basis for the preliminary screening and prediction of the implementation of maintenance and renewal of old pipes, and can avoid the high-cost investment and water supply interruption caused by directly implementing surface excavation for large-scale inner wall detection.

[0093] This application establishes a non-excavation evaluation method for the inner wall corrosion degree of metal water supply pipes with different lining types, which can provide effective technical support for the operation and maintenance of water supply pipes, form a more economical and convenient decision-making basis for pipeline detection, cleaning, repair and renewal, and thus lay a foundation for establishing a long-term operation and maintenance mechanism for urban water supply pipes.

[0094] The following uses a specific embodiment to detail the application process of the evaluation method for the inner wall corrosion degree of the metal water supply pipes of this application, and its application process mainly includes the following steps S1 to S7.

[0095] S1: Obtain the lining type, pipe age, water quality index and pipe wall corrosion degree score of multiple metal water supply pipe samples.

[0096] During the 22-month period from March 9, 2023 to December 2, 2024, 21 metal water supply pipe segments at different sites were collected in a certain city as multiple metal water supply pipe samples, including 6 steel pipes (5 without lining and 1 with cement lining) and 15 cast iron / ductile iron pipes (13 with cement lining and 2 without lining). The information of the collected metal water supply pipes is shown in Table 5.

[0097] Table 5 Information Table of Metal Water Supply Pipes

[0098]

[0099]

[0100] Figure 2 Shows the corrosion condition of the inner wall of the water supply pipe with a cement lining. On the left is a cast iron / ductile iron pipe, and on the right is a steel pipe. Figure 3 Shows the corrosion condition of the inner wall of the water supply pipe without lining protection. On the left is a cast iron pipe, and on the right is a steel pipe). For the corrosion condition of the inner wall of the water supply pipe, to determine the corrosion degree score of its pipe wall, methods such as expert experience method or experimental determination can be used. Judging from the appearance, the pipe wall of the water supply pipe without lining is more severely corroded than that with a cement lining. For example, compared with the DA Road cast iron pipe with a cement lining at 27 years of pipe age, the QJ Road pipe without lining at the same 27 years of pipe age has obvious corrosion nodules. The corrosion on the surface of the steel pipe seems to progress faster than that of the cast iron / ductile iron pipe, especially for the pipes on HX Road, SD Road, MY Road, and XZ Road without a cement lining, showing the rule of HX Road > MY Road > XZ Road > SD Road.

[0101] S2: Calculate the cumulative degree of water body corrosion of each metal water supply pipe sample according to the pipe age and water quality index of each metal water supply pipe sample with the same lining type.

[0102] According to the measured Langelier saturation index and Larson ratio, obtain the corresponding water body corrosion potential score according to Table 2. The water body corrosion potential score is the sum of the water quality corrosion potential scores of the Langelier saturation index and Larson ratio, and the cumulative degree of water body corrosion is the product of the water body corrosion potential score and the buried pipe age (corrosion time). Figure 4 Is the water body corrosion potential score calculated for the water flowing through the metal water supply pipe samples of different lining types. It should be noted that when the LSI or LR corresponding to the upstream and downstream of the metal water supply pipe has different water quality corrosion potential scores, take the average of the two as the final water quality corrosion potential score of LSI or LR.

[0103] S3: Perform function fitting on the cumulative degree of water body corrosion and the threshold of the pipe wall corrosion degree score of multiple metal water supply pipe samples with the same lining type to obtain the pipe wall corrosion degree score model under this lining type.

[0104] For metal water supply pipe samples of different lining types, obtain the corresponding optimal fitting function relationship as the pipe wall corrosion degree score model. Taking 21 metal water supply pipes collected as samples, through Figure 2 and Figure 3Score the corrosion degree of the pipe wall, divide the corrosion degree into four levels: 0-1 (basically intact), 1-2 (mild corrosion), 2-3 (moderate corrosion), and >3 (severe corrosion), and determine the specific score of the pipe wall corrosion degree. Use GraphPad Prism software to fit the cumulative degree of water body corrosion and the score of pipe wall corrosion degree, and obtain the functional relationship between the score of the metal water supply pipe wall corrosion degree under the protection of cement lining and the cumulative degree of water body corrosion as Figure 5 shown. The determined pipe wall corrosion degree scoring model is Y = -8.879e -5 *X 2 + 0.03699*X - 0.5362, R 2 = 0.9121; The functional relationship between the score of the metal water supply pipe wall corrosion degree without lining protection and the cumulative degree of water body corrosion is as Figure 6 shown. The determined pipe wall corrosion degree scoring model is Y = 0.01904*X - 0.2348, R 2 = 0.9352. Where X is the cumulative degree of water body corrosion and Y is the score of pipe wall corrosion degree.

[0105] S4: Obtain the target lining type, target pipe age, and target water quality index of the metal water supply pipe to be evaluated.

[0106] S5: Calculate the target cumulative degree of water body corrosion of the metal water supply pipe to be evaluated according to the target pipe age and target water quality index.

[0107] Based on the Langelier saturation index and Larson ratio of the water body flowing through the metal water supply pipe to be evaluated determined in S4, obtain the corresponding target cumulative degree of water body corrosion according to the calculation method in step 5.

[0108] S6: Substitute the target cumulative degree of water body corrosion into the pipe wall corrosion degree scoring model under the target lining type to calculate the score of the pipe wall corrosion degree of the metal water supply pipe to be evaluated.

[0109] According to the above pipe wall corrosion degree scoring model, the corresponding relationships among the cumulative degree of water body corrosion, the score of pipe wall corrosion degree, and the inner wall corrosion degree of the metal water supply pipe under the protection of cement lining are shown in Table 3, and the corresponding relationships among the cumulative degree of water body corrosion, the score of pipe wall corrosion degree, and the inner wall corrosion degree of the metal water supply pipe without lining protection are shown in Table 4.

[0110] S7: Determine the inner wall corrosion degree of the metal water supply pipe to be evaluated according to the score of the pipe wall corrosion degree of the metal water supply pipe to be evaluated.

[0111] According to the correspondence table between the corrosion degree score of the metal water supply pipe wall with and without cement lining protection in step 6 and the inner wall corrosion degree, qualitatively evaluate the inner wall corrosion degree of the metal water supply pipe to be evaluated. When the corrosion degree reaches moderate corrosion (the corrosion degree score of the pipe wall reaches above 2), enter the maintenance strategy stage. When the corrosion degree reaches severe corrosion (the corrosion degree score of the pipe wall reaches above 3), handle the corresponding metal water supply pipe according to the retirement strategy. This application evaluates the internal corrosion degree of the metal water supply pipe through the pipe network water quality index and pipe age, which can avoid directly implementing ground excavation for evaluation, thus avoiding the high-cost investment and water cut impact of large-scale inner wall inspection through excavation.

[0112] In view of the fact that the qualitative method of directly detecting the inner wall according to the pipe age for the inner wall corrosion degree of the current old metal water supply pipes not only requires huge investment in manpower and material resources but also has extremely high uncertainty and omission situations, this application has developed an evaluation method for the inner wall corrosion degree of metal water supply pipes. This method evaluates the internal corrosion degree of the metal water supply pipe by comprehensively considering the pipe network water quality index and pipe age, avoiding the high-cost investment and water cut impact of directly large-scale inner wall inspection of metal water supply pipes. Compared with the existing methods, this application evaluates the internal corrosion degree of the metal water supply pipe through the pipe network water quality index and pipe age, achieving a more efficient and low-cost corrosion evaluation, avoiding the high costs and complex operations of directly large-scale inner wall inspection of metal water supply pipes. Using the method of this application can monitor the pipeline corrosion status in real time, improve the evaluation efficiency, and contribute to the scientific formulation of the renewal and transformation plan for old pipe networks. Further, due to the relatively stable water supply quality within the target geographical area, the change in the inner wall corrosion degree can also be calculated by changing the pipe age to predict the corrosion trend.

[0113] In an exemplary embodiment, this application also provides a computer device, which can be a server or a terminal. This computer device includes a processor, a memory, an input / output interface, and a communication interface. Among them, the processor, the memory, and the input / output interface are connected through the system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of this computer device is used to provide computing and control capabilities. The memory of this computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of this computer device is used to exchange information between the processor and external devices. The communication interface of this computer device is used to communicate with external terminals through a network connection. When the computer program is executed by the processor, it implements the evaluation method for the inner wall corrosion degree of the metal water supply pipe described above. [[ID=?]] [[ID=?]]

[0114] In an exemplary embodiment, the present application further provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the method for evaluating the corrosion degree of the inner wall of a metal water supply pipe is implemented.

[0115] In an exemplary embodiment, the present application further provides a computer program product, including a computer program, and when the computer program is executed by a processor, the method for evaluating the corrosion degree of the inner wall of a metal water supply pipe is implemented.

[0116] The method for evaluating the corrosion degree of the inner wall of the metal water supply pipe of the present application comprehensively considers various factors such as the water quality index of the water supply network, the pipe age, and the lining type. By means of a non-excavation approach, it can predict the corrosion degree of the inner wall of the metal water supply pipe, avoid the high-cost investment and water interruption impact of directly large-scale excavating and inspecting the inner wall of the pipe, and provide a scientific and accurate reference basis for the renovation and upgrading plan of old pipelines. The present application establishes a non-excavation evaluation method for the corrosion degree of the inner wall of metal water supply pipes with different lining types, which can provide technical support for the operation and maintenance of water supply pipes and lay a foundation for establishing a long-term operation and maintenance mechanism for urban water supply pipes.

[0117] Those of ordinary skill in the art can understand that all or part of the processes in the above-described embodiment methods can be completed by hardware related to computer program instructions. The computer program can be stored in a non-volatile computer-readable storage medium, and when the computer program is executed, it can include the processes of the above-described method embodiments. Among them, any reference to a memory or other medium provided in the various embodiments of the present application can include at least one of non-volatile and volatile memories. Non-volatile memories can include read-only memory (ROM), magnetic tapes, floppy disks, flash memories, optical memories, high-density embedded non-volatile memories, resistive random-access memories (ReRAMs), magnetoresistive random-access memories (MRAMs), ferroelectric random-access memories (FRAMs), phase change memories (PCMs), graphene memories, etc. Volatile memories can include random-access memories (RAMs) or external high-speed caches, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random-access memories (SRAMs) or dynamic random-access memories (DRAMs), etc.

[0118] It should be noted that the information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use, and processing of relevant data need to comply with relevant regulations.

[0119] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0120] Specific examples are used in this article to elaborate on the principles and implementation manners of this application. The description of the above embodiments is only used to help understand the method and its core idea of this application; at the same time, for those of ordinary skill in the art, according to the idea of this application, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to this application.

Claims

1. A method for evaluating the corrosion degree of the inner wall of a metal water supply pipeline, characterized in that Including: Obtain the lining type, pipe age, water quality index, and wall corrosion degree scoring threshold of multiple metal water supply pipe samples; Calculate the cumulative degree of water body corrosion of each metal water supply pipe sample according to the pipe age and water quality index of each metal water supply pipe sample of the same lining type; Perform function fitting on the cumulative degree of water body corrosion and the wall corrosion degree scoring threshold of multiple metal water supply pipe samples of the same lining type to obtain the wall corrosion degree scoring model under this lining type; Obtain the target lining type, target pipe age, and target water quality index of the metal water supply pipe to be evaluated; Calculate the target cumulative degree of water body corrosion of the metal water supply pipe to be evaluated according to the target pipe age and target water quality index; Substitute the target cumulative degree of water body corrosion into the wall corrosion degree scoring model under the target lining type to calculate the wall corrosion degree score of the metal water supply pipe to be evaluated; Determine the inner wall corrosion degree of the metal water supply pipe to be evaluated according to the wall corrosion degree score of the metal water supply pipe to be evaluated.

2. The method for evaluating the corrosion degree of the inner wall of a metal water supply pipe according to claim 1, characterized in that The lining types of the multiple metal water supply pipe samples include no lining, cement lining, and epoxy resin lining; the water quality indices include the Langelier saturation index and the Larson ratio.

3. The method for evaluating the corrosion degree of the inner wall of a metal water supply pipe according to claim 2, characterized in that, The calculating the cumulative degree of water body corrosion of each metal water supply pipe sample according to the pipe age and water quality index of each metal water supply pipe sample of the same lining type specifically includes: For the nth metal water supply pipe sample of the same lining type, according to the Langelier saturation index LSI of the nth metal water supply pipe sample n and the Larson ratio LR n , by looking up the water quality corrosion potential scoring table, determine the water quality corrosion potential scores corresponding to LSI n and LR n ; and where n = 1, 2,..., N; N is the number of metal water supply pipe samples of the same lining type; Use the formula to calculate the cumulative degree of water body corrosion X of the nth metal water supply pipeline sample n ; where CT n is the pipe age of the nth metal water supply pipeline sample 4. The method for evaluating the corrosion degree of the inner wall of a metal water supply pipe according to claim 3, characterized in that, The performing function fitting on the cumulative degree of water body corrosion and the wall corrosion degree scoring threshold of multiple metal water supply pipe samples of the same lining type to obtain the wall corrosion degree scoring model under this lining type specifically includes: For N metal water supply pipe samples of the same lining type, the cumulative degree of water body corrosion X of the nth metal water supply pipe sample n is used as the independent variable, and the wall corrosion degree scoring threshold Y of the nth metal water supply pipe sample n is used as the dependent variable. Multiple functions among linear fitting function, quadratic fitting function, logarithmic fitting function, exponential fitting function, locally weighted regression function, logistic fitting function, piecewise fitting function and power function are used for fitting respectively, and the correlation coefficient R 2 > 0.9 and the highest functional relationship is selected as the wall corrosion degree scoring model under this lining type.

5. The method for evaluating the corrosion degree of the inner wall of a metal water supply pipe according to claim 4, characterized in that, When the lining type of multiple metal water supply pipe samples is no lining, the wall corrosion degree scoring model under no lining protection is Y = 0.01904*X - 0.2348; where X represents the cumulative degree of water body corrosion; Y represents the wall corrosion degree score.

6. The method for evaluating the corrosion degree of the inner wall of a metal water supply pipe according to claim 4, wherein, When the lining type of multiple metal water supply pipe samples is cement lining, the scoring model for the corrosion degree of the pipe wall protected by the cement lining is Y = -8.879e -5 *X 2 + 0.03699*X - 0.5362; where X represents the cumulative degree of water body corrosion; Y represents the scoring of the pipe wall corrosion degree.

7. The method for evaluating the corrosion degree of the inner wall of a metal water supply pipe according to claim 1, wherein, The determining the inner wall corrosion degree of the metal water supply pipe to be evaluated according to the wall corrosion degree score of the metal water supply pipe to be evaluated specifically includes: When the wall corrosion degree score of the metal water supply pipe to be evaluated is between 0 and 1, determine that the inner wall corrosion degree of the metal water supply pipe to be evaluated is basically intact; When the wall corrosion degree score of the metal water supply pipe to be evaluated is between 1 and 2, determine that the inner wall corrosion degree of the metal water supply pipe to be evaluated is slightly corroded; When the wall corrosion degree score of the metal water supply pipe to be evaluated is between 2 and 3, determine that the inner wall corrosion degree of the metal water supply pipe to be evaluated is moderately corroded; When the wall corrosion degree score of the metal water supply pipe to be evaluated is greater than 3, determine that the inner wall corrosion degree of the metal water supply pipe to be evaluated is severely corroded.

8. A computer device, comprising: A memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor executes the computer program to implement the method for evaluating the inner wall corrosion degree of a metal water supply pipe according to any one of claims 1 to 7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the method for evaluating the inner wall corrosion degree of a metal water supply pipe according to any one of claims 1 to 7.

10. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the method for evaluating the corrosion degree of the inner wall of a metal water supply pipeline according to any one of claims 1 to 7.

Images