Evaluation method, evaluation device and management system for crack type defect of hydrogen conveying pipeline

Abstract

The invention provides a crack type defect evaluation method and device for a hydrogen conveying pipeline and a management system. The method comprises the steps that basic information of the hydrogen conveying pipeline is obtained; determining test conditions according to the basic information and test equipment requirements; respectively carrying out tensile test and fracture toughness test on multiple groups of non-hydrogen absorption samples and multiple groups of hydrogen absorption samples under test conditions to obtain multiple tensile curves and multiple fracture toughness; a failure evaluation curve of the hydrogen conveying pipeline is established based on the tensile curve under the saturated hydrogen absorption time and the multiple fracture toughness; detecting a crack type defect of the hydrogen conveying pipeline by adopting a pipeline defect detection technology, and determining an evaluation point of the crack type defect; and under the condition that the ordinates of the evaluation points are larger than the ordinates of the corresponding failure evaluation points, the hydrogen conveying pipeline is controlled to stop running, and alarm information is sent out. The method solves the technical problem that in the prior art, the safety of the hydrogen conveying pipeline cannot be determined through safety evaluation of cracks caused by the hydrogen induced cracking mechanism of the hydrogen conveying pipeline.

Description

Technical Field

[0001] The present invention relates to the field of safety evaluation of the pipe body and weld defects of hydrogen transmission pipelines. Specifically, it relates to a method and device for evaluating crack-type defects of hydrogen transmission pipelines, a computer-readable storage medium, and a hydrogen transmission pipeline management system. Background Technique

[0002] As a link and bridge between hydrogen production and hydrogen utilization, hydrogen energy storage and transportation is crucial for the sustainable development of the entire hydrogen energy industry chain. However, with the continuous expansion of the hydrogen energy application market, the hydrogen supply guarantee problem of hydrogen energy storage and transportation infrastructure will also become an important factor restricting the large-scale development of the industry. Safe and efficient storage and transportation is one of the key technologies for hydrogen energy utilization. Pipeline hydrogen transmission is an economically feasible way to achieve large-scale and long-distance hydrogen energy transmission. It not only helps the utilization of industrial by-product hydrogen and hydrogen produced from renewable energy, but also can reduce the storage and transportation costs under large-scale transmission conditions. However, implementing an effective in-service hydrogen transmission pipeline defect safety evaluation is crucial for ensuring the safe operation of hydrogen transmission pipelines.

[0003] Since hydrogen molecules are extremely small and can easily penetrate into the interior of steel pipes, a large number of cracks are generated due to hydrogen-induced cracking during the operation and service of pipelines, mainly manifested as relatively serious crack-type defects. Traditional safety evaluation methods for steel pipes with crack-type defects, such as standards like SY / T 6477 or API 579, are mainly based on the failure assessment diagram method. However, due to the changes in the mechanical properties and plastic limit load of steel pipes in a hydrogen environment, the existing failure assessment diagram method cannot be applied to the safety evaluation of pipelines. Currently, there is no mature safety evaluation method for hydrogen transmission pipelines in the industry. Therefore, it is urgent to establish a safety evaluation method for hydrogen transmission pipelines with crack-type defects to provide a basic guarantee for the integrity management of in-service hydrogen transmission pipelines. Summary of the Invention

[0004] The main objective of the present application is to provide a method and device for evaluating crack-type defects of hydrogen transmission pipelines, a computer-readable storage medium, and a hydrogen transmission pipeline management system, so as to at least solve the problem in the prior art that the safety evaluation of cracks in hydrogen transmission pipelines caused by the hydrogen-induced cracking mechanism has not been realized to determine the safety of hydrogen transmission pipelines.

[0005] To achieve the above object, according to one aspect of the present application, there is provided a method for evaluating crack-type defects of a hydrogen transmission pipeline, including: obtaining basic information of the hydrogen transmission pipeline, and selecting a material specimen according to the basic information, where the basic information includes pipeline material, pipeline diameter, pipeline wall thickness, and pipeline operating pressure; determining test conditions according to the basic information and the requirements of a high-pressure gas-phase thermal hydrogen charging test device, where the test conditions include test temperature, test pressure, and hydrogen absorption time, and the hydrogen absorption time is the duration of charging hydrogen into the material specimen, and the hydrogen absorption time includes saturated hydrogen absorption time and unsaturated hydrogen absorption time; performing tensile tests and fracture toughness tests on multiple groups of non-hydrogen-absorbing specimens and multiple groups of hydrogen-absorbing specimens respectively under the test conditions to obtain multiple tensile curves and multiple fracture toughness values, where the non-hydrogen-absorbing specimens are specimens that do not undergo hydrogen charging treatment on the material specimen, and the hydrogen-absorbing specimens are specimens that undergo hydrogen charging treatment on the material specimen, and the tensile curve is a relationship curve between stress and strain of the material specimen under the action of a tensile force; establishing a failure assessment curve of the hydrogen transmission pipeline based on the tensile curve and multiple fracture toughness values under the saturated hydrogen absorption time, where the failure assessment curve is a relationship curve between the load ratio and the fracture ratio, the fracture ratio is the ratio of the stress intensity factor to the fracture toughness, the load ratio is the ratio of the reference stress to the yield strength, and the yield strength is the highest stress value before the first drop in the tensile curve; using pipeline defect detection technology to detect crack-type defects of the hydrogen transmission pipeline and determining an evaluation point of the crack-type defect, where the evaluation point is a position coordinate point in the coordinate system where the failure assessment curve is located; in the case where the ordinate of the evaluation point is greater than the ordinate of the corresponding failure assessment point, controlling the hydrogen transmission pipeline to stop operating and sending an alarm message, where the failure assessment point is a point on the failure assessment curve with the same abscissa as the evaluation point, and the alarm message is used to prompt that the hydrogen transmission pipeline is in an unsafe state with a cracking risk due to crack-type defects.

[0006] Optionally, before establishing the failure assessment curve of the hydrogen transmission pipeline based on the tensile curve and multiple fracture toughness values under the saturated hydrogen absorption time, the method further includes: establishing a first degradation model of the fracture toughness and the hydrogen absorption time according to multiple fracture toughness values, where the first degradation model is a degradation model used to characterize the linear relationship between the fracture toughness and the hydrogen absorption time, and the input data of the first degradation model is the hydrogen absorption time, and the output data is the fracture toughness value corresponding to the hydrogen absorption time.

[0007] Optionally, after establishing the failure assessment curve of the hydrogen transmission pipeline based on the tensile curve and multiple fracture toughness values at the saturated hydrogen absorption time, the method further includes: obtaining multiple yield strengths and multiple ultimate tensile strengths from multiple tensile curves, each tensile curve including one yield strength and one ultimate tensile strength, and the ultimate tensile strength being the maximum stress value corresponding in the tensile curve; establishing a second degradation model of the yield strength and the hydrogen absorption time based on the multiple yield strengths, the second degradation model being a degradation model for characterizing the linear relationship between the yield strength and the hydrogen absorption time, with the input data of the second degradation model being the hydrogen absorption time and the output data being the yield strength corresponding to the hydrogen absorption time; establishing a third degradation model of the ultimate tensile strength and the hydrogen absorption time based on the multiple ultimate tensile strengths, the third degradation model being a degradation model for characterizing the linear relationship between the ultimate tensile strength and the hydrogen absorption time, with the input data of the third degradation model being the hydrogen absorption time and the output data being the ultimate tensile strength corresponding to the hydrogen absorption time; determining the saturated hydrogen absorption yield strength and the saturated hydrogen absorption ultimate tensile strength according to the second degradation model and the third degradation model respectively, the saturated hydrogen absorption yield strength being the yield strength when the hydrogen absorption time reaches the saturated hydrogen absorption time, and the saturated hydrogen absorption ultimate tensile strength being the ultimate tensile strength when the hydrogen absorption time reaches the saturated hydrogen absorption time; calculating the ratio of the sum of the strengths to twice the saturated hydrogen absorption yield strength to obtain a cut-off value, drawing a straight line perpendicular to the horizontal axis in the coordinate system according to the cut-off value and determining it as the cut-off line, the sum of the strengths being the sum of the saturated hydrogen absorption yield strength and the saturated hydrogen absorption ultimate tensile strength, the highest point of the cut-off line being the intersection point with the failure assessment curve, and the area enclosed by the cut-off line, the failure assessment curve, the horizontal axis and the vertical axis being the safe area.

[0008] Optionally, determining the saturated hydrogen absorption yield strength and the saturated hydrogen absorption ultimate tensile strength according to the second degradation model and the third degradation model respectively includes: in the case where the hydrogen absorption time of the second degradation model reaches the saturated hydrogen absorption time, determining the saturated hydrogen absorption yield strength according to the saturated hydrogen absorption time and the yield strength when not absorbing hydrogen; in the case where the hydrogen absorption time of the third degradation model reaches the saturated hydrogen absorption time, determining the saturated hydrogen absorption ultimate tensile strength according to the saturated hydrogen absorption time and the ultimate tensile strength when not absorbing hydrogen.

[0009] Optionally, pipeline defect detection technology is adopted to detect the defects of the hydrogen transmission pipeline and determine the evaluation points of the crack-type defects, including: detecting the hydrogen transmission pipeline by using the pipeline defect detection technology to determine the defect length and the self-height of the defect of the hydrogen transmission pipeline; substituting the saturated hydrogen absorption time and the minimum yield strength during non-hydrogen absorption into the second degradation model to calculate the minimum saturated hydrogen absorption yield strength; substituting the saturated hydrogen absorption time and the minimum fracture toughness during non-hydrogen absorption into the third degradation model to calculate the minimum saturated hydrogen absorption fracture toughness; substituting the defect length, the self-height of the defect and the basic information of the hydrogen transmission pipeline into the stress intensity factor formula and the reference stress formula respectively to calculate the stress intensity factor and the reference stress; calculating the fracture ratio of the evaluation point according to the ratio of the stress intensity factor to the minimum saturated hydrogen absorption fracture toughness and calculating the load ratio of the evaluation point according to the ratio of the reference stress to the minimum saturated hydrogen absorption yield strength; determining the evaluation point according to the load ratio and the fracture ratio.

[0010] Optionally, after detecting the defects of the hydrogen transmission pipeline by using the pipeline defect detection technology and determining the evaluation points of the crack-type defects, it includes: when the evaluation point is in the safe area, the hydrogen transmission pipeline operates normally and controls the issuance of a prompt message, and the prompt message is used to prompt that the defects of the hydrogen transmission pipeline are within the safe range and will not cause cracking.

[0011] Optionally, according to the basic information and the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment, the test conditions are determined, including: determining the test temperature and the test pressure in the test conditions according to the performance of the test equipment; measuring the change of the hydrogen content inside the material specimen with the hydrogen charging time under the conditions of the test temperature and the test pressure to determine the time threshold, and the time threshold is the time point when the hydrogen content no longer changes with the hydrogen charging time; when the hydrogen charging time reaches the time threshold, determining the hydrogen charging time as the saturated hydrogen absorption time, and the saturated hydrogen absorption time is the total time when the hydrogen content no longer changes with the hydrogen charging time; when the hydrogen charging time does not reach the time threshold, determining the hydrogen charging time as the unsaturated hydrogen absorption time.

[0012] According to another aspect of the present application, there is provided a crack-type defect evaluation device for a hydrogen transmission pipeline, including: an acquisition unit configured to acquire basic information of the hydrogen transmission pipeline and select a material specimen according to the basic information, where the basic information includes pipeline material, pipeline diameter, pipeline wall thickness, and pipeline operating pressure; a first determination unit configured to determine test conditions according to the basic information and the requirements of a high-pressure gas-phase thermal hydrogen charging test device, where the test conditions include test temperature, test pressure, and hydrogen absorption time, and the hydrogen absorption time is the duration of hydrogen charging to the material specimen, and the hydrogen absorption time includes saturated hydrogen absorption time and unsaturated hydrogen absorption time; a test unit configured to perform tensile tests and fracture toughness tests on multiple groups of non-hydrogen-absorbing specimens and multiple groups of hydrogen-absorbing specimens respectively under the test conditions to obtain multiple tensile curves and multiple fracture toughness values. The non-hydrogen-absorbing specimen is a specimen that does not undergo hydrogen charging treatment on the material specimen, and the hydrogen-absorbing specimen is a specimen that undergoes hydrogen charging treatment on the material specimen. The tensile curve is a relationship curve between stress and strain of the material specimen under the action of a tensile force; a first establishment unit configured to establish a failure assessment curve of the hydrogen transmission pipeline based on the tensile curve and the multiple fracture toughness values under the saturated hydrogen absorption time. The failure assessment curve is a relationship curve between a load ratio and a fracture ratio. The fracture ratio is the ratio of the stress intensity factor to the fracture toughness, and the load ratio is the ratio of the reference stress to the yield strength. The yield strength is the highest stress value before the first drop in the tensile curve; a second determination unit configured to detect crack-type defects of the hydrogen transmission pipeline using pipeline defect detection technology and determine an evaluation point of the crack-type defect. The evaluation point is a position coordinate point in the coordinate system where the failure assessment curve is located; a first control unit configured to, when the ordinate of the evaluation point is greater than the ordinate of the corresponding failure assessment point, control the hydrogen transmission pipeline to stop operating and send an alarm message. The failure assessment point is a point on the failure assessment curve with the same abscissa as the evaluation point, and the alarm message is used to prompt that the hydrogen transmission pipeline is in an unsafe state with a cracking risk due to crack-type defects.

[0013] According to yet another aspect of the present application, there is provided a computer-readable storage medium, where the computer-readable storage medium includes a stored program, and when the program runs, it controls the device where the computer-readable storage medium is located to execute any one of the above methods.

[0014] According to yet another aspect of the present application, there is provided a hydrogen transmission pipeline evaluation system, including: one or more processors, a memory, and one or more programs, where the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include those for executing any one of the above methods.

[0015] Applying the technical solution of the present application in the crack-type defect evaluation method of a hydrogen transmission pipeline, first, obtain the basic information of the hydrogen transmission pipeline, and select a material specimen according to the basic information. The basic information includes pipeline material, pipeline diameter, pipeline wall thickness, and pipeline operating pressure; then, determine the test conditions according to the basic information and the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment. The test conditions include test temperature, test pressure, and hydrogen absorption time. The hydrogen absorption time is the duration of hydrogen charging into the material specimen, and the hydrogen absorption time includes saturated hydrogen absorption time and unsaturated hydrogen absorption time; then, under the test conditions, conduct tensile tests and fracture toughness tests on multiple groups of non-hydrogen-absorbing specimens and multiple groups of hydrogen-absorbing specimens respectively to obtain multiple tensile curves and multiple fracture toughness values. The non-hydrogen-absorbing specimen is a specimen that does not undergo hydrogen charging treatment on the material specimen, and the hydrogen-absorbing specimen is a specimen that undergoes hydrogen charging treatment on the material specimen. The tensile curve is the relationship curve between stress and strain of the material specimen under the action of tensile force; then, establish a failure assessment curve for the hydrogen transmission pipeline based on the tensile curve and multiple fracture toughness values under the saturated hydrogen absorption time. The failure assessment curve is the relationship curve between the load ratio and the fracture ratio. The fracture ratio is the ratio of the stress intensity factor to the fracture toughness, and the load ratio is the ratio of the reference stress to the yield strength. The yield strength is the highest stress value before the first drop in the tensile curve; then, use pipeline defect detection technology to detect the crack-type defects of the hydrogen transmission pipeline and determine the evaluation points of the crack-type defects. The evaluation point is the position coordinate point in the coordinate system where the failure assessment curve is located; finally, when the ordinate of the evaluation point is greater than the ordinate of the corresponding failure assessment point, control the hydrogen transmission pipeline to stop operating and send an alarm message. The failure assessment point is the point on the failure assessment curve with the same abscissa as the evaluation point. The alarm message is used to prompt that the hydrogen transmission pipeline is in an unsafe state due to crack-type defects and has a risk of cracking. The present application selects the same specification steel pipe material as the hydrogen transmission pipeline, determines the test conditions according to the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment, puts the tensile property and fracture toughness test specimens into the high-pressure gas-phase thermal hydrogen charging test equipment, conducts hydrogen charging tests according to the test conditions, establishes a failure assessment curve, and uses pipeline defect detection technology for the hydrogen transmission pipeline to determine the defect situation, determines the evaluation point of the hydrogen transmission pipeline according to the defect situation, and determines that the defect of the hydrogen transmission pipeline is unsafe and may cause cracking when the evaluation point is in the non-safe area of the failure assessment curve, and then controls to send an alarm. The present application solves the technical problem in the prior art that the safety evaluation of the hydrogen transmission pipeline for cracks caused by the hydrogen-induced cracking mechanism has not been realized to determine the safety of the hydrogen transmission pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 FIG. shows a hardware structure block diagram of a mobile terminal for implementing a crack-type defect evaluation method of a hydrogen transmission pipeline provided in an embodiment of the present application;

[0017] Figure 2 FIG. shows a flowchart of a crack-type defect evaluation method of a hydrogen transmission pipeline provided in an embodiment of the present application;

[0018] Figure 3 Shows a schematic diagram of the tensile test results provided according to an embodiment of the present application;

[0019] Figure 4 Shows a specific failure assessment diagram in an embodiment of the present application;

[0020] Figure 5 Shows a failure assessment diagram of a crack-type defect evaluation method for a hydrogen transmission pipeline provided according to an embodiment of the present application;

[0021] Figure 6 Shows a schematic diagram of the yield strength degradation curve provided according to an embodiment of the present application;

[0022] Figure 7 Shows a schematic diagram of the tensile strength degradation curve provided according to an embodiment of the present application;

[0023] Figure 8 Shows a schematic diagram of the fracture toughness degradation curve provided according to an embodiment of the present application;

[0024] Figure 9 Shows a schematic diagram of the safety applicability evaluation results of a gas transmission pipeline provided according to an embodiment of the present application;

[0025] Figure 10 Shows a schematic flow diagram of a specific crack-type defect evaluation method for a hydrogen transmission pipeline provided according to an embodiment of the present application;

[0026] Figure 11 Shows a structural block diagram of a crack-type defect evaluation device for a hydrogen transmission pipeline provided according to an embodiment of the present application.

[0027] Among them, the above-mentioned drawings include the following reference numerals:

[0028] 102, processor; 104, memory; 106, transmission device; 108, input / output device. Detailed implementation manners

[0029] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0030] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0031] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0032] For the convenience of description, some nouns or terms involved in the embodiments of the present application are explained below:

[0033] Crack-type defect: a surface defect with a sharp root. The main parameters are crack depth and length. It generally includes surface cracks, buried cracks and through cracks.

[0034] Failure assessment diagram: A method used to evaluate the applicability of structures with crack-type defects. The ordinate is the toughness ratio (fracture ratio) and the abscissa is the load ratio. It can evaluate whether the structure with crack-type defects has brittle fracture or plastic instability. If the assessment point is within or exactly on the assessment curve, the crack-type defect is considered acceptable, otherwise, it is considered unacceptable.

[0035] Stress intensity factor: a parameter that characterizes the stress and strain state at the crack tip of an elastic material and controls the instability and expansion, that is, a physical quantity that reflects the strength of the elastic stress field at the crack tip;

[0036] Reference stress: reflects the stress magnitude at the crack tip;

[0037] Yield strength: the yield limit of metal materials when they yield, that is, the stress that resists slight plastic deformation;

[0038] Fracture toughness: When there is a crack or a crack-like defect in a specimen or component, the material will no longer fracture rapidly with the increase of load, that is, when the so-called unstable fracture occurs;

[0039] Tensile strength: The maximum stress value that a material can withstand before being pulled apart.

[0040] As introduced in the background art, the existing failure assessment diagram method in the prior art cannot be applied to the safety assessment of pipelines. Currently, there is no mature safety assessment method for hydrogen transmission pipelines in the industry. To solve the problem that the safety assessment of cracks caused by the hydrogen-induced cracking mechanism in hydrogen transmission pipelines has not been realized in the prior art to determine the safety of hydrogen transmission pipelines, the embodiments of the present application provide a crack-type defect assessment method, an assessment device, a computer-readable storage medium, and a hydrogen transmission pipeline management system for hydrogen transmission pipelines.

[0041] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention.

[0042] The method embodiments provided in the embodiments of the present application can be executed on a mobile terminal, a computer terminal, or a similar computing device. Taking running on a mobile terminal as an example, Figure 1 is a hardware structure block diagram of a mobile terminal for a crack-type defect assessment method of a hydrogen transmission pipeline according to an embodiment of the present invention. As Figure 1 shown, the mobile terminal may include one or more ( Figure 1 only one is shown in Figure 1 processors 102 (the processors 102 may include, but are not limited to, processing devices such as a microprocessor MCU or a programmable logic device FPGA) and a memory 104 for storing data. Among them, the above mobile terminal may further include a transmission device 106 for communication functions and an input / output device 108. Those of ordinary skill in the art can understand that Figure 1 the structure shown in Figure 1 is only schematic and does not limit the structure of the above mobile terminal. For example, the mobile terminal may further include more or fewer components than

[0043] The memory 104 can be used to store computer programs, for example, software programs and modules of application software, such as the computer program corresponding to the display method of device information in the embodiments of the present invention. The processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, that is, implements the above-mentioned method. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memories, or other non-volatile solid-state memories. In some instances, the memory 104 may further include a memory remotely disposed relative to the processor 102, and these remote memories can be connected to the mobile terminal through a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an enterprise intranet, a local area network, a mobile communication network, and combinations thereof. The transmission device 106 is used to receive or send data via a network. Specific examples of the above-mentioned network may include a wireless network provided by a communication provider of the mobile terminal. In one instance, the transmission device 106 includes a network adapter (Network Interface Controller, abbreviated as NIC), which can be connected to other network devices through a base station and thus can communicate with the Internet. In one instance, the transmission device 106 may be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0044] In this embodiment, a method for evaluating crack-type defects of a hydrogen transmission pipeline operating on a mobile terminal, a computer terminal, or a similar computing device is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0045] Figure 2 It is a flowchart of the method for evaluating crack-type defects of a hydrogen transmission pipeline according to an embodiment of the present application. As Figure 2 shown, the method includes the following steps:

[0046] Step S201, obtain the basic information of the hydrogen transmission pipeline, and select a material specimen according to the basic information. The basic information includes pipeline material, pipeline diameter, pipeline wall thickness, and pipeline operating pressure.

[0047] Specifically, collect information such as pipeline material, operating pressure, diameter, and wall thickness required for the applicability evaluation of the hydrogen transmission pipeline, and select steel pipe materials of the same specification as the pipeline, that is, the above-mentioned material specimens.

[0048] Step S202: Determine the test conditions according to the basic information and the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment. The test conditions include the test temperature, test pressure, and hydrogen absorption time. The hydrogen absorption time is the duration of hydrogen charging into the material specimen, and the hydrogen absorption time includes the saturated hydrogen absorption time and the unsaturated hydrogen absorption time.

[0049] Specifically, establish the test conditions for simulating temperature, pressure, and hydrogen absorption time according to the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment and the pipeline operation conditions. The high-pressure gas-phase thermal hydrogen charging test equipment can be equipment such as a high-pressure gas adsorption and desorption analyzer.

[0050] Step S203: Conduct tensile tests and fracture toughness tests on multiple groups of non-hydrogen-absorbing specimens and multiple groups of hydrogen-absorbing specimens respectively under the test conditions to obtain multiple tensile curves and multiple fracture toughness values. Non-hydrogen-absorbing specimens are specimens that do not undergo hydrogen charging treatment on the material specimen, and hydrogen-absorbing specimens are specimens that undergo hydrogen charging treatment on the material specimen. A tensile curve is a relationship curve between stress and strain of the material specimen under the action of a tensile force.

[0051] Specifically, in accordance with GB-T 228.1 "Metallic materials - Tensile testing - Part 1: Method of test at room temperature", conduct tensile tests on at least 1 group of non-hydrogen-charged specimens and at least 2 groups of hydrogen-absorbing specimens, and measure the tensile property curves of each group of specimens. As Figure 3 shown, there are two methods for the fracture toughness test. Method 1: Conduct fracture toughness tests on at least 1 group of non-hydrogen-charged specimens and at least 2 groups of hydrogen-absorbing specimens in accordance with GB / T 21143 "Unified test method for quasi-static fracture toughness of metallic materials" to obtain the fracture toughness. Method 2: Conduct Charpy impact toughness tests on at least 1 group of non-hydrogen-charged specimens and at least 2 groups of hydrogen-absorbing specimens in accordance with GBT 229 "Metallic materials - Charpy pendulum impact test method", and then estimate the fracture toughness using the Charpy impact energy according to the method in Section 7.4 of SY / T6477. Of course, the method is not limited to this, and those skilled in the art can choose other appropriate methods for the test.

[0052] Step S204: Establish a failure assessment curve for the hydrogen transmission pipeline based on the tensile curve and multiple fracture toughness values under the saturated hydrogen absorption time. The failure assessment curve is a relationship curve between the load ratio and the fracture ratio. The fracture ratio is the ratio of the stress intensity factor to the fracture toughness, and the load ratio is the ratio of the reference stress to the yield strength. The yield strength is the highest stress value before the first drop in the tensile curve.

[0053] Specifically, based on the tensile property curve under the saturated hydrogen absorption time and multiple fracture toughness values, establish a failure assessment curve for the hydrogen transmission pipeline using the method of "Assessment method for integrity of structures containing defects", as Figure 4 shown. Of course, the method is not limited to this, and those skilled in the art can choose other appropriate methods for the test.

[0054] Step S205: Detect crack-type defects in the hydrogen transmission pipeline using pipeline defect detection technology, and determine the evaluation points of the crack-type defects. The evaluation points are position coordinate points in the coordinate system where the failure assessment curve is located.

[0055] Specifically, non-destructive testing of the pipeline should use in-line inspection or external inspection methods to determine the crack-type defect conditions, such as the axial length and the self-height of the defect. In-line inspection can use relatively effective in-line crack detection technology (such as ultrasonic crack in-line detector); external inspection uses a combined detection method of ray + ultrasonic. The ultrasonic detection method can use a combination of manual ultrasonic and ultrasonic phased array or TOFD. The detection process should be carried out in accordance with the relevant regulations of SY / T 4109 "Non-destructive Testing of Steel Pipelines for Oil and Gas", and determine the position of the evaluation points of the crack-type defects according to the defect conditions.

[0056] Step S206: When the ordinate of the evaluation point is greater than the ordinate of the corresponding failure assessment point, control the hydrogen transmission pipeline to stop running and send an alarm message. The failure assessment point is the point on the failure assessment curve with the same abscissa as the evaluation point. The alarm message is used to prompt that the hydrogen transmission pipeline is in an unsafe state with a risk of cracking due to crack-type defects.

[0057] Specifically, when the ordinate of the evaluation point is greater than the ordinate of the corresponding failure assessment point, it indicates that the evaluation point is in the non-safe area at this time. The hydrogen transmission pipeline is in an unsafe state with a risk of cracking due to crack-type defects. Therefore, it is necessary to immediately control the gas transmission pipeline to stop running and send an alarm message to remind the operator.

[0058] Through the above embodiments, first, obtain the basic information of the hydrogen transmission pipeline, and select a material specimen according to the basic information, where the basic information includes pipeline material, pipeline diameter, pipeline wall thickness, and pipeline operating pressure; then, determine the test conditions according to the basic information and the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment, where the test conditions include test temperature, test pressure, and hydrogen absorption time, and the hydrogen absorption time is the duration of hydrogen charging into the material specimen, and the hydrogen absorption time includes saturated hydrogen absorption time and unsaturated hydrogen absorption time; then, under the test conditions, conduct tensile tests and fracture toughness tests on multiple groups of non-hydrogen-absorbing specimens and multiple groups of hydrogen-absorbing specimens respectively to obtain multiple tensile curves and multiple fracture toughness values. The non-hydrogen-absorbing specimen is a specimen that does not undergo hydrogen charging treatment on the material specimen, and the hydrogen-absorbing specimen is a specimen that undergoes hydrogen charging treatment on the material specimen. The tensile curve is the relationship curve between stress and strain of the material specimen under the action of tensile force; then, based on the tensile curve and multiple fracture toughness values under the saturated hydrogen absorption time, establish a failure assessment curve for the hydrogen transmission pipeline. The failure assessment curve is the relationship curve between the load ratio and the fracture ratio. The fracture ratio is the ratio of the stress intensity factor to the fracture toughness, and the load ratio is the ratio of the reference stress to the yield strength. The yield strength is the highest stress value before the first drop in the tensile curve; then, use pipeline defect detection technology to detect crack-type defects in the hydrogen transmission pipeline and determine the evaluation points of the crack-type defects. The evaluation points are the position coordinate points in the coordinate system where the failure assessment curve is located; finally, when the ordinate of the evaluation point is greater than the ordinate of the corresponding failure assessment point, control the hydrogen transmission pipeline to stop running and send an alarm message. The failure assessment point is the point on the failure assessment curve with the same abscissa as the evaluation point. The alarm message is used to prompt that the hydrogen transmission pipeline is in an unsafe state due to crack-type defects and has a risk of cracking. In this application, by selecting the same specification steel pipe material for the hydrogen transmission pipeline, determining the test conditions according to the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment, putting the tensile performance and fracture toughness test specimens into the high-pressure gas-phase thermal hydrogen charging test equipment, conducting the hydrogen charging test according to the test conditions, establishing a failure assessment curve, and using pipeline defect detection technology for the hydrogen transmission pipeline to determine the defect situation, determining the evaluation point of the hydrogen transmission pipeline according to the defect situation, and determining that the defect of the hydrogen transmission pipeline is unsafe and may cause cracking when the evaluation point is in the non-safe area of the failure assessment curve, then controlling to send an alarm. This application solves the technical problem in the prior art that the safety evaluation of the hydrogen transmission pipeline for cracks caused by the hydrogen-induced cracking mechanism has not been realized to determine the safety of the hydrogen transmission pipeline.

[0059] In order to enable those skilled in the art to more clearly understand the technical solution of this application, the implementation process of the crack-type defect evaluation method for the hydrogen transmission pipeline of this application will be described in detail below in combination with specific embodiments.

[0060] In order to ensure the accuracy of the test, in an alternative embodiment, step S202 includes:

[0061] Step S2021: Determine the test temperature and test pressure in the test conditions according to the performance of the test equipment.

[0062] Specifically, the temperature and pressure can be determined according to the maximum simulation working conditions of the test equipment. For example, the temperature is 200 °C and the pressure is 12 MPa.

[0063] Step S2022: Measure the change of the hydrogen content inside the material specimen with the hydrogen charging time under the conditions of the test temperature and test pressure, and determine the time threshold. The time threshold is the time point when the hydrogen content no longer changes with the hydrogen charging time.

[0064] Specifically, according to GB / T 223.82 "Determination of Hydrogen Content in Iron and Steel - Inert Gas Fusion - Thermal Conductivity or Infrared Method", measure the change curve of the hydrogen content inside the specimen with the hydrogen charging time under the condition of thermal hydrogen charging, and observe the time threshold from the change curve. The condition of thermal hydrogen charging is the above-mentioned conditions of the test temperature and test pressure.

[0065] Step S2023: When the hydrogen charging time reaches the time threshold, determine the hydrogen charging time as the saturated hydrogen absorption time. The saturated hydrogen absorption time is the total time when the hydrogen content no longer changes with the hydrogen charging time.

[0066] Specifically, determine the total time when the hydrogen content no longer changes with the hydrogen charging time as the saturated hydrogen absorption time.

[0067] Step S2024: When the hydrogen charging time does not reach the time threshold, determine the hydrogen charging time as the unsaturated hydrogen absorption time.

[0068] Specifically, determine the time when the hydrogen content changes with the hydrogen charging time as the saturated hydrogen absorption time.

[0069] In order to intuitively understand the fracture toughness performance of the gas transmission pipeline, in an alternative embodiment, before step S204, the method further includes:

[0070] Step S301: Establish a first degradation model of fracture toughness and hydrogen absorption time according to multiple fracture toughnesses. The first degradation model is a degradation model used to characterize the linear relationship between fracture toughness and hydrogen absorption time. The input data of the first degradation model is the hydrogen absorption time, and the output data is the fracture toughness corresponding to the hydrogen absorption time, so as to intuitively understand the fracture toughness performance of the gas transmission pipeline.

[0071] Specifically, based on the fracture toughness results of non-hydrogen-absorbing specimens (equivalent hydrogen absorption of 0 hours) and multiple hydrogen-absorbing specimens, fit and establish a degradation law model of fracture toughness and hydrogen absorption time, that is, the above-mentioned first degradation model. Specifically, such as; K matH = k1 * t + K mat where K matH is the hydrogen-absorbing fracture toughness, k1 is the curve slope, t is the hydrogen absorption time, and K matHis the fracture toughness before hydrogen absorption. When t is the saturation hydrogen absorption time, the corresponding fracture toughness after hydrogen absorption is the saturation hydrogen absorption fracture toughness K matBH .

[0072] In order to determine the safety of crack-type defects, in an alternative embodiment, after step S204, the method further includes:

[0073] Step S401: Obtain a plurality of yield strengths and a plurality of tensile strengths from a plurality of tensile curves. Each tensile curve includes a yield strength and a tensile strength, and the tensile strength is the maximum stress value corresponding in the tensile curve.

[0074] Specifically, the yield strength and tensile strength on each curve are observed from a plurality of tensile curves.

[0075] Step S402: Establish a second degradation model of the yield strength and the hydrogen absorption time according to the plurality of yield strengths. The second degradation model is a degradation model used to characterize the linear relationship between the yield strength and the hydrogen absorption time. The input data of the second degradation model is the hydrogen absorption time, and the output data is the yield strength corresponding to the hydrogen absorption time;

[0076] Specifically, based on the yield strength results of non-hydrogen-absorbing specimens (equivalent hydrogen absorption of 0 hours) and a plurality of hydrogen-absorbing specimens, a degradation law model of the yield strength and the hydrogen absorption time is fitted and established, that is, the above-mentioned second degradation model. Specifically, such as σ yH = k2 * t + σ y , where σ yH is the yield strength after hydrogen absorption, k2 is the curve slope, t is the hydrogen absorption time, and σ y is the yield strength before hydrogen absorption.

[0077] Step S403: Establish a third degradation model of the tensile strength and the hydrogen absorption time according to the plurality of tensile strengths. The third degradation model is a degradation model used to characterize the linear relationship between the tensile strength and the hydrogen absorption time. The input data of the third degradation model is the hydrogen absorption time, and the output data is the tensile strength corresponding to the hydrogen absorption time;

[0078] Specifically, based on the tensile strength results of non-hydrogen-absorbing specimens (equivalent hydrogen absorption of 0 hours) and a plurality of hydrogen-absorbing specimens, a degradation law model of the tensile strength and the hydrogen absorption time is fitted and established, that is, the above-mentioned third degradation model. Specifically, such as σ uH = k3 * t + σ u ; where σ uH is the tensile strength after hydrogen absorption, k3 is the curve slope, t is the hydrogen absorption time, and σ u is the tensile strength before hydrogen absorption.

[0079] Step S404: Determine the saturated hydrogen absorption yield strength and the saturated hydrogen absorption tensile strength according to the second degradation model and the third degradation model respectively. The saturated hydrogen absorption yield strength is the yield strength when the hydrogen absorption time reaches the saturated hydrogen absorption time, and the saturated hydrogen absorption tensile strength is the tensile strength when the hydrogen absorption time reaches the saturated hydrogen absorption time.

[0080] Specifically, when t is the saturated hydrogen absorption time, the corresponding hydrogen absorption yield strength is the saturated hydrogen absorption yield strength σ yBH and the corresponding hydrogen absorption tensile strength is the saturated hydrogen absorption tensile strength σ uBH .

[0081] Step S405: Calculate the ratio of the sum of the strengths to twice the saturated hydrogen absorption yield strength to obtain the cut-off value. Draw a straight line perpendicular to the horizontal axis in the coordinate system according to the cut-off value and determine it as the cut-off line. The sum of the strengths is the sum of the saturated hydrogen absorption yield strength and the saturated hydrogen absorption tensile strength. The highest point of the cut-off line is the intersection point with the failure assessment curve. The area enclosed by the cut-off line, the failure assessment curve, the horizontal axis and the vertical axis is the safe area.

[0082] Specifically, the cut-off line is obtained according to the saturated hydrogen absorption yield strength and the saturated hydrogen absorption tensile strength The specific position is as Figure 5 shown. The area enclosed by the cut-off line, the failure assessment curve, the horizontal axis and the vertical axis is the safe area, that is Figure 5 the area represented by O(Lr, Kr) in

[0083] To ensure the accuracy and repeatability of the test results, in an optional implementation manner, Step S404 includes:

[0084] Step S4041: When the hydrogen absorption time of the second degradation model reaches the saturated hydrogen absorption time, determine the saturated hydrogen absorption yield strength according to the saturated hydrogen absorption time and the yield strength without hydrogen absorption.

[0085] Specifically, a specific yield strength degradation model can be fitted and established, that is, the above-mentioned second degradation model: σ yH = 0.3446t + σ y , as Figure 6 shown. The yield strength at 0 hour of hydrogen absorption is 325 MPa. When t is the saturated hydrogen absorption time of 120 hours, the corresponding hydrogen absorption yield strength, that is, the saturated hydrogen absorption yield strength, is 0.3446×120 + 325 = 366.352 MPa.

[0086] Step S4042: When the hydrogen absorption time of the third degradation model reaches the saturated hydrogen absorption time, determine the saturated hydrogen absorption tensile strength according to the saturated hydrogen absorption time and the tensile strength without hydrogen absorption.

[0087] Specifically, a specific tensile strength degradation model can be fitted and established, that is, the above-mentioned third degradation model: σ uH = 0.362t + σ u , as Figure 7 shown, the tensile strength at 0 hours of hydrogen absorption is 425 MPa. When t is the saturated hydrogen absorption time of 120 hours, the corresponding hydrogen absorption yield strength is the saturated hydrogen absorption yield strength of 0.362×120 + 425 = 468.44 MPa.

[0088] In order to ensure the safe operation of the gas transmission pipeline, in an optional implementation manner, step S205 includes:

[0089] Step S2051: Detect the hydrogen transmission pipeline using pipeline defect detection technology to determine the defect length and the height of the defect itself;

[0090] Specifically, for pipeline girth weld defects, the ultrasonic detection method can adopt manual ultrasonic and ultrasonic phased array external detection methods to determine the defect length and the height of the defect itself, where the height of the defect itself is the defect thickness of the defect accounting for the wall thickness.

[0091] Step S2052: Substitute the saturated hydrogen absorption time and the minimum yield strength at non-hydrogen absorption into the second degradation model to calculate the minimum saturated hydrogen absorption yield strength;

[0092] Specifically, substitute the minimum value of the yield strength required by the steel pipe standard, 245 MPa, into the degradation law model of yield strength and hydrogen charging time, that is, the above-mentioned second degradation model. Take the saturated hydrogen charging time of 120 hours to obtain the minimum saturated hydrogen absorption yield strength σ yBHX = 0.3446×120 + 245 = 286.352 MPa.

[0093] Step S2053: Substitute the saturated hydrogen absorption time and the minimum fracture toughness at non-hydrogen absorption into the third degradation model to calculate the minimum saturated hydrogen absorption fracture toughness;

[0094] Specifically, substitute the minimum value of the Charpy impact energy (CVN) of a single specimen required by the steel pipe standard, 20 J, into the fracture toughness at non-hydrogen absorption estimated by the method of Charpy impact energy in SY / T 6477: Kmat = min(8.47(CVN) 0.63 , 14.6(CVN) 0.6 ) = 55.916 MPa. As Figure 8 shown, fit a specific degradation law model of fracture toughness and hydrogen charging time, that is, the above-mentioned third degradation model is K matH = -0.1185t + K mat , take the saturated hydrogen charging time of 120 hours to obtain the minimum saturated hydrogen absorption fracture toughness of K matBHX= -0.1185×120 + 55.916 = 41.696 MPa.

[0095] Step S2054: Substitute the defect length, the defect's own height, and the basic information of the hydrogen pipeline into the stress intensity factor formula and the reference stress formula respectively to calculate the stress intensity factor and the reference stress.

[0096] Specifically, substitute the defect length, the defect's own height, and the basic information of the hydrogen pipeline into the stress intensity factor formula and the reference stress formula respectively to calculate the stress intensity factor and the reference stress. The specific stress intensity factor formula and reference stress formula refer to Appendix B and Appendix C of SYT 6477 - 2017 "Evaluation Method for Remaining Strength of Oil and Gas Pipelines with Defects".

[0097] Step S2055: Calculate the fracture ratio at the evaluation point according to the ratio of the stress intensity factor to the minimum saturated hydrogen absorption fracture toughness, and calculate the load ratio at the evaluation point according to the ratio of the reference stress to the minimum saturated hydrogen absorption yield strength.

[0098] Specifically, the ratio of the stress intensity factor to the minimum saturated hydrogen absorption fracture toughness is used to calculate the vertical fracture ratio, and the ratio of the reference stress to the minimum saturated hydrogen absorption yield strength is used to calculate the horizontal load ratio.

[0099] Step S2056: Determine the evaluation point according to the load ratio and the fracture ratio.

[0100] Specifically, the position of the evaluation point can be determined according to the load ratio and the fracture ratio of the horizontal and vertical coordinates, as Figure 9 shown.

[0101] To improve production efficiency and save maintenance costs, in an alternative embodiment, after step S205, the method further includes:

[0102] Step S501: When the evaluation point is in the safe area, the hydrogen pipeline operates normally and controls the issuance of a prompt message, which is used to prompt that the defect of the hydrogen pipeline is within the safe range and will not cause cracking.

[0103] Specifically, as Figure 10 shown, when the evaluation point is within the safe area of the failure assessment diagram, it indicates that the crack - type defect is acceptable, the gas transmission pipeline continues to operate normally, and controls the issuance of a prompt message to inform the operator.

[0104] This embodiment relates to a specific method for evaluating crack - type defects of a hydrogen pipeline. As Figure 10 shown, it includes the following steps:

[0105] Step S1: Collect basic information of the hydrogen pipeline, formulate a high-pressure gas-phase hot hydrogen charging test plan. For example, select steel pipes of the same specification as the pipeline, and process at least 3 sets of test specimens for tensile properties, fracture toughness, or impact toughness according to the requirements of the high-pressure gas-phase hot hydrogen charging test equipment. Establish the accelerated simulation temperature, pressure, and hydrogen absorption time according to the requirements of the high-pressure gas-phase hot hydrogen charging test equipment and the pipeline operation conditions;

[0106] Step S2: Start the hot hydrogen charging test. For the tensile test, in accordance with GB-T 228.1 "Metallic materials - Tensile testing - Part 1: Method of test at room temperature", conduct tensile tests on at least 1 set of non-hydrogen-charged specimens and at least 2 sets of specimens with different hydrogen charging times, test the tensile property curves, yield strength, and tensile strength of each group of specimens. Then, based on the yield strength and tensile strength tested from the non-hydrogen-absorbing specimens (equivalent hydrogen absorption of 0 hours) and the hydrogen-absorbing specimens, respectively fit and establish the degradation law models of yield strength versus hydrogen charging time and tensile strength versus hydrogen charging time;

[0107] Step S3: Conduct fracture toughness tests on 1 set of non-hydrogen-charged specimens and at least 2 sets of specimens with different hydrogen charging times in accordance with GB / T 21143 "Unified test method for quasi-static fracture toughness of metallic materials" to obtain the fracture toughness. Or conduct Charpy impact toughness tests on at least 1 set of non-hydrogen-absorbing specimens and at least 2 sets of hydrogen-absorbing specimens in accordance with GBT 229 "Metallic materials - Charpy pendulum impact test method". Then, estimate the fracture toughness using the Charpy impact energy according to the method in Section 7.4 of SY / T 6477. Based on the fracture toughness results of the non-hydrogen-absorbing specimens (equivalent hydrogen absorption of 0 hours) and different hydrogen-absorbing specimens, fit and establish the degradation law model of fracture toughness versus hydrogen charging time;

[0108] Step S4: Establish a failure assessment diagram for saturated hydrogen-absorbing pipe materials;

[0109] Step S5: Detect crack-type defects using relatively effective crack internal detection techniques (such as ultrasonic crack detectors) for internal detection or a detection method combining ray and ultrasonic for external detection;

[0110] Step S6: Conduct an applicability evaluation on the crack-type defects. If the defects are acceptable, operate normally; if the crack-type defects are unacceptable, stop operation for repair.

[0111] It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. And although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0112] The embodiments of the present application also provide a crack-type defect evaluation device for a hydrogen transmission pipeline. It should be noted that the crack-type defect evaluation device for the hydrogen transmission pipeline in the embodiments of the present application can be used to execute the crack-type defect evaluation method for the hydrogen transmission pipeline provided by the embodiments of the present application. The device for implementing the above embodiments and preferred implementation manners has been described and will not be repeated here. As used below, the term "module" can be a combination of software and / or hardware that realizes a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware is also possible and contemplated.

[0113] The following introduces the crack-type defect evaluation device for the hydrogen transmission pipeline provided by the embodiments of the present application.

[0114] Figure 11 is a structural block diagram of the crack-type defect evaluation device for the hydrogen transmission pipeline according to the embodiments of the present application. As Figure 11 shown, the device includes:

[0115] An acquisition unit 10, configured to acquire basic information of the hydrogen transmission pipeline and select a material specimen according to the basic information. The basic information includes pipeline material, pipeline diameter, pipeline wall thickness, and pipeline operating pressure.

[0116] Specifically, collect information such as pipeline material, operating pressure, diameter, and wall thickness required for the applicability evaluation of the hydrogen transmission pipeline, and select steel pipe materials of the same specification as the pipeline, that is, the above material specimens.

[0117] A first determination unit 20, configured to determine test conditions according to the basic information and the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment. The test conditions include test temperature, test pressure, and hydrogen absorption time. The hydrogen absorption time is the duration of hydrogen charging to the material specimen, and the hydrogen absorption time includes saturated hydrogen absorption time and unsaturated hydrogen absorption time.

[0118] Specifically, establish test conditions simulating temperature, pressure, and hydrogen absorption time according to the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment and the pipeline operating conditions. The high-pressure gas-phase thermal hydrogen charging test equipment can be equipment such as a high-pressure gas adsorption and desorption analyzer.

[0119] A test unit 30, configured to perform tensile tests and fracture toughness tests on multiple groups of non-hydrogen-absorbing specimens and multiple groups of hydrogen-absorbing specimens respectively under the test conditions to obtain multiple tensile curves and multiple fracture toughnesses. The non-hydrogen-absorbing specimen is a specimen that does not undergo hydrogen charging treatment on the material specimen, and the hydrogen-absorbing specimen is a specimen that undergoes hydrogen charging treatment on the material specimen. The tensile curve is the relationship curve between stress and strain of the material specimen under the action of a tensile force.

[0120] Specifically, in accordance with GB-T 228.1 "Metallic materials - Tensile testing - Part 1: Method of test at room temperature", tensile tests are carried out on at least 1 group of non-hydrogen-charged specimens and at least 2 groups of hydrogen-absorbed specimens, and the tensile property curves of each group of specimens are measured. For the fracture toughness test, there are two methods. Method 1: In accordance with GB / T 21143 "Unified test method for quasi-static fracture toughness of metallic materials", fracture toughness tests are carried out on at least 1 group of non-hydrogen-charged specimens and at least 2 groups of hydrogen-absorbed specimens to obtain the fracture toughness. Method 2: In accordance with GBT229 "Charpy pendulum impact test method for metallic materials", Charpy impact toughness tests are carried out on at least 1 group of non-hydrogen-charged specimens and at least 2 groups of hydrogen-absorbed specimens, and then the fracture toughness is estimated using the Charpy impact energy according to the method in Section 7.4 of SY / T 6477. Of course, the method is not limited to this, and those skilled in the art can choose other suitable methods for the test.

[0121] The first establishing unit 40 is used to establish a failure assessment curve of the hydrogen transmission pipeline based on the tensile curve at the saturated hydrogen absorption time and multiple fracture toughnesses. The failure assessment curve is a relationship curve between the load ratio and the fracture ratio. The fracture ratio is the ratio of the stress intensity factor to the fracture toughness, and the load ratio is the ratio of the reference stress to the yield strength. The yield strength is the highest stress value before the first drop in the tensile curve.

[0122] Specifically, based on the tensile property curve at the saturated hydrogen absorption time and multiple fracture toughnesses, the failure assessment curve of the hydrogen transmission pipeline is established by using the method of "Assessment method for integrity of structures containing defects". Of course, the method is not limited to this, and those skilled in the art can choose other suitable methods for the test.

[0123] The second determining unit 50 is used to detect the crack-type defects of the hydrogen transmission pipeline by using pipeline defect detection technology and determine the evaluation points of the crack-type defects. The evaluation points are the position coordinate points in the coordinate system where the failure assessment curve is located.

[0124] Specifically, for pipeline non-destructive testing, internal detection or external detection methods should be used to determine the crack-type defect situation, such as the axial length and the self-height of the defect. For internal detection, relatively effective crack internal detection technology (such as ultrasonic crack internal detector) can be used; for external detection, a detection method combining ray and ultrasonic is used. The ultrasonic detection method can adopt a method combining manual ultrasonic and ultrasonic phased array or TOFD. The detection process should be carried out in accordance with the relevant regulations of SY / T 4109 "Non-destructive testing of steel pipelines for oil and gas". And the position of the evaluation points of the crack-type defects is determined according to the defect situation.

[0125] The first control unit 60 is configured to control the hydrogen pipeline to stop operating and issue an alarm message when the ordinate of the evaluation point is greater than the ordinate of the corresponding failure evaluation point. The failure evaluation point is the point on the failure evaluation curve with the same abscissa as the evaluation point. The alarm message is used to indicate that the hydrogen pipeline is in an unsafe state due to crack-type defects and has a risk of cracking.

[0126] Specifically, when the ordinate of the evaluation point is greater than the ordinate of the corresponding failure evaluation point, it indicates that the evaluation point is in the non-safe area at this time. The hydrogen pipeline is in an unsafe state due to crack-type defects and has a risk of cracking. Therefore, it is necessary to immediately control the gas pipeline to stop operating and issue an alarm message to alert the operator.

[0127] Through this embodiment, an acquisition unit is configured to acquire the basic information of the hydrogen transmission pipeline and select a material specimen according to the basic information. The basic information includes pipeline material, pipeline diameter, pipeline wall thickness, and pipeline operating pressure. A first determination unit is configured to determine test conditions according to the basic information and the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment. The test conditions include test temperature, test pressure, and hydrogen absorption time. The hydrogen absorption time is the duration of hydrogen charging to the material specimen, and the hydrogen absorption time includes saturated hydrogen absorption time and unsaturated hydrogen absorption time. A test unit is configured to perform tensile tests and fracture toughness tests on multiple groups of non-hydrogen absorption specimens and multiple groups of hydrogen absorption specimens respectively under the test conditions to obtain multiple tensile curves and multiple fracture toughness values. The non-hydrogen absorption specimen is a specimen that does not undergo hydrogen charging treatment on the material specimen, and the hydrogen absorption specimen is a specimen that undergoes hydrogen charging treatment on the material specimen. The tensile curve is the relationship curve between stress and strain of the material specimen under the action of tensile force. A first establishment unit is configured to establish a failure assessment curve of the hydrogen transmission pipeline based on the tensile curve and multiple fracture toughness values under the saturated hydrogen absorption time. The failure assessment curve is the relationship curve between the load ratio and the fracture ratio. The fracture ratio is the ratio of the stress intensity factor to the fracture toughness, and the load ratio is the ratio of the reference stress to the yield strength. The yield strength is the highest stress value before the first drop in the tensile curve. A second determination unit is configured to detect crack-type defects of the hydrogen transmission pipeline using pipeline defect detection technology and determine the evaluation points of the crack-type defects. The evaluation points are position coordinate points in the coordinate system where the failure assessment curve is located. A first control unit is configured to control the hydrogen transmission pipeline to stop operating and send an alarm message when the ordinate of the evaluation point is greater than the ordinate of the corresponding failure assessment point. The failure assessment point is the point on the failure assessment curve with the same abscissa as the evaluation point. The alarm message is used to prompt that the hydrogen transmission pipeline is in an unsafe state with a cracking risk due to crack-type defects. In this application, by selecting steel pipe materials of the same specification as the hydrogen transmission pipeline, determining the test conditions according to the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment, putting the tensile performance and fracture toughness test specimens into the high-pressure gas-phase thermal hydrogen charging test equipment, conducting hydrogen charging tests according to the test conditions, establishing a failure assessment curve, and using pipeline defect detection technology to determine the defect situation of the hydrogen transmission pipeline, determining the evaluation points of the hydrogen transmission pipeline according to the defect situation, and determining that the defects of the hydrogen transmission pipeline are unsafe and may cause cracking when the evaluation points are in the non-safe area of the failure assessment curve, then controlling to send an alarm. This application solves the technical problem in the prior art that the safety evaluation of the hydrogen transmission pipeline for cracks caused by the hydrogen-induced cracking mechanism has not been realized to determine the safety of the hydrogen transmission pipeline.

[0128] To ensure the accuracy of the test, in an alternative embodiment, the first determination unit includes:

[0129] A first determination module is configured to determine the test temperature and test pressure in the test conditions according to the performance of the test equipment.

[0130] Specifically, the temperature and pressure can be determined according to the maximum simulated working conditions of the test equipment, such as a temperature of 200 °C and a pressure of 12 MPa.

[0131] A second determination module measures the change in the hydrogen content inside the material specimen with the hydrogen charging time under the conditions of the test temperature and the test pressure, and determines a time threshold, where the time threshold is the time point when the hydrogen content no longer changes with the hydrogen charging time.

[0132] Specifically, according to GB / T 223.82 "Determination of Hydrogen Content in Iron and Steel - Inert Gas Fusion - Thermal Conductivity or Infrared Method", the change curve of the hydrogen content inside the specimen with the hydrogen charging time under the conditions of thermal hydrogen charging is measured, and the time threshold is observed from the change curve. The conditions of thermal hydrogen charging are the above-mentioned test temperature and test pressure conditions.

[0133] A third determination module, when the hydrogen charging time reaches the time threshold, determines the hydrogen charging time as the saturated hydrogen absorption time, where the saturated hydrogen absorption time is the total time when the hydrogen content no longer changes with the hydrogen charging time.

[0134] Specifically, the total time when the hydrogen content no longer changes with the hydrogen charging time is determined as the saturated hydrogen absorption time.

[0135] A fourth determination module, when the hydrogen charging time does not reach the time threshold, determines the hydrogen charging time as the unsaturated hydrogen absorption time.

[0136] Specifically, the time when the hydrogen content changes with the hydrogen charging time is determined as the saturated hydrogen absorption time.

[0137] In order to intuitively understand the fracture toughness performance of the gas transmission pipeline, in an optional implementation, the device further includes:

[0138] A second establishment unit is used to establish a first degradation model of the fracture toughness and the hydrogen absorption time based on multiple fracture toughnesses before establishing a failure assessment curve of the hydrogen transmission pipeline based on the tensile curve and multiple fracture toughnesses under the saturated hydrogen absorption time. The first degradation model is a degradation model used to characterize the linear relationship between the fracture toughness and the hydrogen absorption time. The input data of the first degradation model is the hydrogen absorption time, and the output data is the fracture toughness corresponding to the hydrogen absorption time, so as to intuitively understand the fracture toughness performance of the gas transmission pipeline.

[0139] Specifically, based on the fracture toughness results of non-hydrogen-absorbing specimens (equivalent hydrogen absorption of 0 hours) and multiple hydrogen-absorbing specimens, a degradation law model of the fracture toughness and the hydrogen absorption time is fitted and established, that is, the above-mentioned first degradation model. Specifically, for example; K matH = k1 * t + K mat , where K matH is the fracture toughness after hydrogen absorption, k1 is the curve slope, t is the hydrogen absorption time, and K matHis the fracture toughness before hydrogen absorption. When t is the saturation hydrogen absorption time, the corresponding fracture toughness of hydrogen absorption is the saturation hydrogen absorption fracture toughness K matBH .

[0140] In order to determine the safety of crack-type defects, in an alternative embodiment, the device further includes:

[0141] An acquisition unit, after establishing a failure assessment curve of the hydrogen transmission pipeline based on the tensile curve and multiple fracture toughnesses at the saturation hydrogen absorption time, obtains multiple yield strengths and multiple tensile strengths through multiple tensile curves. Each tensile curve includes a yield strength and a tensile strength, and the tensile strength is the maximum stress value corresponding in the tensile curve.

[0142] Specifically, the yield strength and tensile strength on each curve are observed from multiple tensile curves.

[0143] A third establishment unit, configured to establish a second degradation model of the yield strength and the hydrogen absorption time according to multiple yield strengths. The second degradation model is a degradation model used to characterize the linear relationship between the yield strength and the hydrogen absorption time. The input data of the second degradation model is the hydrogen absorption time, and the output data is the yield strength corresponding to the hydrogen absorption time;

[0144] Specifically, based on the non-hydrogen-absorbing specimen (equivalent hydrogen absorption of 0 hours) and the yield strength results of multiple hydrogen-absorbing specimens, a degradation law model of the yield strength and the hydrogen absorption time is fitted and established, that is, the above-mentioned second degradation model. Specifically, such as σ yH = k2 * t + σ y , where σ yH is the hydrogen absorption yield strength, k2 is the curve slope, t is the hydrogen absorption time, and σ y is the yield strength before hydrogen absorption.

[0145] A fourth establishment unit, configured to establish a third degradation model of the tensile strength and the hydrogen absorption time according to multiple tensile strengths. The third degradation model is a degradation model used to characterize the linear relationship between the tensile strength and the hydrogen absorption time. The input data of the third degradation model is the hydrogen absorption time, and the output data is the tensile strength corresponding to the hydrogen absorption time;

[0146] Specifically, based on the non-hydrogen-absorbing specimen (equivalent hydrogen absorption of 0 hours) and the tensile strength results of multiple hydrogen-absorbing specimens, a degradation law model of the tensile strength and the hydrogen absorption time is fitted and established, that is, the above-mentioned third degradation model. Specifically, such as σ uH = k3 * t + σ u ; where σ uH is the hydrogen absorption tensile strength, k3 is the curve slope, t is the hydrogen absorption time, and σ u is the tensile strength before hydrogen absorption.

[0147] A third determination unit, configured to determine the saturated hydrogen absorption yield strength and the saturated hydrogen absorption tensile strength according to the second degradation model and the third degradation model respectively. The saturated hydrogen absorption yield strength is the yield strength when the hydrogen absorption time reaches the saturated hydrogen absorption time, and the saturated hydrogen absorption tensile strength is the tensile strength when the hydrogen absorption time reaches the saturated hydrogen absorption time.

[0148] Specifically, when t is the saturated hydrogen absorption time, the corresponding hydrogen absorption yield strength is the saturated hydrogen absorption yield strength σ yBH and the corresponding hydrogen absorption tensile strength is the saturated hydrogen absorption tensile strength σ uBH .

[0149] A calculation unit, configured to calculate the ratio of the strength sum to twice the saturated hydrogen absorption yield strength to obtain a cut-off value, draw a straight line perpendicular to the horizontal axis in the coordinate system according to the cut-off value and determine it as the cut-off line. The strength sum is the sum of the saturated hydrogen absorption yield strength and the saturated hydrogen absorption tensile strength. The highest point of the cut-off line is the intersection point with the failure assessment curve. The area enclosed by the cut-off line, the failure assessment curve, the horizontal axis and the vertical axis is the safe area.

[0150] Specifically, the cut-off line is obtained according to the saturated hydrogen absorption yield strength and the saturated hydrogen absorption tensile strength

[0151] In order to ensure the accuracy and repeatability of the test results, in an optional implementation manner, the third determination unit includes:

[0152] A fifth determination module, when the hydrogen absorption time of the second degradation model reaches the saturated hydrogen absorption time, determines the saturated hydrogen absorption yield strength according to the saturated hydrogen absorption time and the yield strength without hydrogen absorption.

[0153] Specifically, a specific yield strength degradation model can be fitted and established, that is, the above-mentioned second degradation model: σ yH = 0.3446t + σ y . When the yield strength at 0 hour of hydrogen absorption is 325 MPa, when t is the saturated hydrogen absorption time of 120 hours, the corresponding hydrogen absorption yield strength, that is, the saturated hydrogen absorption yield strength, is 0.3446×120 + 325 = 366.352 MPa.

[0154] A sixth determination module, when the hydrogen absorption time of the third degradation model reaches the saturated hydrogen absorption time, determines the saturated hydrogen absorption tensile strength according to the saturated hydrogen absorption time and the tensile strength without hydrogen absorption.

[0155] Specifically, a specific tensile strength degradation model can be fitted and established, that is, the above-mentioned third degradation model: σ uH = 0.362t + σ u, the tensile strength at 0 hours of hydrogen absorption is 425 MPa. When t is the saturated hydrogen absorption time of 120 hours, the corresponding hydrogen absorption yield strength is the saturated hydrogen absorption yield strength of 0.362×120 + 425 = 468.44 MPa.

[0156] To ensure the safe operation of the gas transmission pipeline, in an alternative embodiment, the second determination unit includes:

[0157] A detection module that detects the hydrogen transmission pipeline using pipeline defect detection technology to determine the defect length and the height of the defect itself;

[0158] Specifically, for pipeline girth weld defects, ultrasonic testing methods can use manual ultrasonic and ultrasonic phased array external testing methods to determine the defect length and the height of the defect itself, where the height of the defect itself is the defect thickness of the defect occupying the wall thickness.

[0159] A first calculation module that substitutes the saturated hydrogen absorption time and the minimum yield strength during non-hydrogen absorption into the second degradation model to calculate the minimum saturated hydrogen absorption yield strength;

[0160] Specifically, substituting the minimum value of the yield strength required by the steel pipe standard, 245 MPa, into the degradation law model of yield strength and hydrogen charging time, that is, the above-mentioned second degradation model, and taking the saturated hydrogen charging time of 120 hours, the minimum saturated hydrogen absorption yield strength σ yBHX = 0.3446×120 + 245 = 286.352 MPa.

[0161] A second calculation module that substitutes the saturated hydrogen absorption time and the minimum fracture toughness during non-hydrogen absorption into the third degradation model to calculate the minimum saturated hydrogen absorption fracture toughness;

[0162] Specifically, substituting the minimum value of the Charpy impact energy (CVN) of a single specimen required by the steel pipe standard, 20 J, into the method of SY / T 6477 to estimate the fracture toughness during non-hydrogen absorption: Kmat = min(8.47(CVN) 0.63 , 14.6(CVN) 0.6 ) = 55.916 MPa, fitting the specific degradation law model of fracture toughness and hydrogen charging time, that is, the above-mentioned third degradation model is K matH = -0.1185t + K mat , taking the saturated hydrogen charging time of 120 hours, the minimum saturated hydrogen absorption fracture toughness is K matBHX = -0.1185×120 + 55.916 = 41.696 MPa.

[0163] A third calculation module that substitutes the defect length, the height of the defect itself, and the basic information of the hydrogen transmission pipeline into the stress intensity factor formula and the reference stress formula to calculate the stress intensity factor and the reference stress respectively;

[0164] Specifically, substitute the defect length, the height of the defect itself, and the basic information of the hydrogen transmission pipeline into the stress intensity factor formula and the reference stress formula to calculate the stress intensity factor and the reference stress respectively. The specific stress intensity factor formula and reference stress formula refer to Appendix B and Appendix C of SYT 6477-2017 "Evaluation Method for Remaining Strength of Oil and Gas Pipelines with Defects".

[0165] The fourth calculation module calculates the fracture ratio of the evaluation point based on the ratio of the stress intensity factor to the minimum saturated hydrogen absorption fracture toughness, and calculates the load ratio of the evaluation point based on the ratio of the reference stress to the minimum saturated hydrogen absorption yield strength.

[0166] Specifically, the ratio of the stress intensity factor to the minimum saturated hydrogen absorption fracture toughness is used to calculate the vertical coordinate fracture ratio, and the ratio of the reference stress to the minimum saturated hydrogen absorption yield strength is used to calculate the horizontal coordinate load ratio.

[0167] The seventh determination module determines the evaluation point based on the load ratio and the fracture ratio.

[0168] Specifically, the position of the evaluation point can be determined according to the load ratio and the fracture ratio of the horizontal and vertical coordinates.

[0169] In order to improve production efficiency and save maintenance costs, in an alternative embodiment, the device further includes:

[0170] The second control unit is configured to, after detecting a crack-type defect of the hydrogen transmission pipeline by using pipeline defect detection technology and determining the evaluation point of the crack-type defect, when the evaluation point is in the safe area, the hydrogen transmission pipeline operates normally and controls the issuance of a prompt message, and the prompt message is used to prompt that the defect of the hydrogen transmission pipeline is within the safe range and will not cause cracking.

[0171] Specifically, when the evaluation point is within the safe area of the failure assessment diagram, it indicates that the crack-type defect is acceptable, the gas transmission pipeline continues to operate normally, and controls the issuance of a prompt message to inform the operator.

[0172] The above crack-type defect evaluation device for a hydrogen transmission pipeline includes a processor and a memory. The above acquisition unit, test unit, etc. are all stored in the memory as program units, and the corresponding functions are realized by the processor executing the above program units stored in the memory. The above modules are all located in the same processor; or, the above modules are respectively located in different processors in any combination form.

[0173] The processor contains a kernel, and the kernel retrieves the corresponding program unit from the memory. One or more kernels can be set, and by adjusting the kernel parameters, the problem of not being able to determine the safety of the hydrogen transmission pipeline by realizing the safety evaluation of cracks caused by the hydrogen-induced cracking mechanism of the hydrogen transmission pipeline can be solved.

[0174] The memory may include non - permanent memory in a computer - readable medium, in the form of random access memory (RAM) and / or non - volatile memory, such as read - only memory (ROM) or flash RAM. The memory includes at least one storage chip.

[0175] An embodiment of the present invention provides a computer - readable storage medium. The above - mentioned computer - readable storage medium stores a program. When the above - mentioned program runs, it controls the device where the computer - readable storage medium is located to execute the method for evaluating crack - type defects of the hydrogen - transmission pipeline.

[0176] Specifically, the method for evaluating crack - type defects of the hydrogen - transmission pipeline includes:

[0177] Step S201: Obtain the basic information of the hydrogen - transmission pipeline, and select a material specimen according to the basic information. The basic information includes pipeline material, pipeline diameter, pipeline wall thickness, and pipeline operating pressure.

[0178] Step S202: Determine the test conditions according to the basic information and the requirements of the high - pressure gas - phase thermal hydrogen - charging test equipment. The test conditions include test temperature, test pressure, and hydrogen - absorption time. The hydrogen - absorption time is the duration of hydrogen charging into the material specimen, and the hydrogen - absorption time includes saturated hydrogen - absorption time and unsaturated hydrogen - absorption time.

[0179] Step S203: Conduct tensile tests and fracture toughness tests on multiple groups of non - hydrogen - absorption specimens and multiple groups of hydrogen - absorption specimens respectively under the test conditions to obtain multiple tensile curves and multiple fracture toughness values. The non - hydrogen - absorption specimen is a specimen that does not undergo hydrogen - charging treatment on the material specimen, and the hydrogen - absorption specimen is a specimen that undergoes hydrogen - charging treatment on the material specimen. The tensile curve is the relationship curve between stress and strain of the material specimen under the action of tensile force.

[0180] Step S204: Establish a failure assessment curve for the hydrogen - transmission pipeline based on the tensile curve and multiple fracture toughness values under saturated hydrogen - absorption time. The failure assessment curve is the relationship curve between the load ratio and the fracture ratio. The fracture ratio is the ratio of the stress intensity factor to the fracture toughness, and the load ratio is the ratio of the reference stress to the yield strength. The yield strength is the highest stress value before the first drop in the tensile curve.

[0181] Step S205: Use pipeline defect detection technology to detect crack - type defects of the hydrogen - transmission pipeline and determine the evaluation points of the crack - type defects. The evaluation points are position coordinate points in the coordinate system where the failure assessment curve is located.

[0182] Step S206: When the ordinate of the evaluation point is greater than the ordinate of the corresponding failure assessment point, control the hydrogen - transmission pipeline to stop running and send an alarm message. The failure assessment point is the point on the failure assessment curve with the same abscissa as the evaluation point. The alarm message is used to prompt that the hydrogen - transmission pipeline is in an unsafe state due to crack - type defects and has a risk of cracking.

[0183] An embodiment of the present invention provides a processor for running a program. When the program runs, it executes the method for evaluating crack-type defects of the hydrogen transmission pipeline.

[0184] An embodiment of the present invention provides a gas transmission pipeline management system, which includes a processor, a memory, and a program stored on the memory and executable on the processor. When the processor executes the program, it implements the method for evaluating crack-type defects of the hydrogen transmission pipeline.

[0185] This application also provides a computer program product, which, when executed on a data processing device, is adapted to execute a program initialized with at least the following method steps:

[0186] Step S201: Obtain the basic information of the hydrogen transmission pipeline, and select a material specimen according to the basic information. The basic information includes pipeline material, pipeline diameter, pipeline wall thickness, and pipeline operating pressure.

[0187] Step S202: Determine the test conditions according to the basic information and the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment. The test conditions include test temperature, test pressure, and hydrogen absorption time. The hydrogen absorption time is the duration of hydrogen charging into the material specimen, and the hydrogen absorption time includes saturated hydrogen absorption time and unsaturated hydrogen absorption time.

[0188] Step S203: Conduct tensile tests and fracture toughness tests on multiple groups of non-hydrogen-absorbing specimens and multiple groups of hydrogen-absorbing specimens respectively under the test conditions to obtain multiple tensile curves and multiple fracture toughness values. The non-hydrogen-absorbing specimen is a specimen that does not undergo hydrogen charging treatment on the material specimen, and the hydrogen-absorbing specimen is a specimen that undergoes hydrogen charging treatment on the material specimen. The tensile curve is the relationship curve between stress and strain of the material specimen under the action of tensile force.

[0189] Step S204: Establish a failure assessment curve for the hydrogen transmission pipeline based on the tensile curve and multiple fracture toughness values under the saturated hydrogen absorption time. The failure assessment curve is the relationship curve between the load ratio and the fracture ratio. The fracture ratio is the ratio of the stress intensity factor to the fracture toughness, and the load ratio is the ratio of the reference stress to the yield strength. The yield strength is the highest stress value before the first drop in the tensile curve.

[0190] Step S205: Use pipeline defect detection technology to detect the crack-type defects of the hydrogen transmission pipeline, and determine the evaluation points of the crack-type defects. The evaluation points are the position coordinate points in the coordinate system where the failure assessment curve is located.

[0191] Step S206: When the ordinate of the evaluation point is greater than the ordinate of the corresponding failure evaluation point, control the hydrogen pipeline to stop running and send an alarm message. The failure evaluation point is the point on the failure evaluation curve with the same abscissa as the evaluation point. The alarm message is used to prompt that the hydrogen pipeline is in an unsafe state due to crack-type defects and has a risk of cracking.

[0192] Obviously, those skilled in the art should understand that the above-mentioned modules or steps of the present invention can be implemented by a general-purpose computing device. They can be concentrated on a single computing device or distributed on a network composed of multiple computing devices. They can be implemented by program codes executable by the computing device. Thus, they can be stored in a storage device and executed by the computing device. And in some cases, the steps shown or described herein can be executed in a different order, or they can be separately fabricated into individual integrated circuit modules, or multiple modules or steps among them can be fabricated into a single integrated circuit module for implementation. In this way, the present invention is not limited to any specific combination of hardware and software.

[0193] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program codes.

[0194] The present application is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to the processors of general-purpose computers, special-purpose computers, embedded processors, or other programmable data processing devices to generate a machine, so that the instructions executed by the processors of the computer or other programmable data processing devices generate means for implementing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0195] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured article including an instruction device, and the instruction device implements the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1the functions specified in one or more boxes.

[0196] These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable device provide for implementing the steps of the functions specified in one Figure 1 one process or more processes and / or boxes Figure 1 step of the functions specified in one or more boxes.

[0197] In a typical configuration, a computing device includes one or more processors (CPUs), an input / output interface, a network interface, and memory.

[0198] The memory may include non-permanent memory in the computer-readable medium, in the form of random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash memory (flash RAM). The memory is an example of a computer-readable medium.

[0199] Computer-readable media includes permanent and non-permanent, removable and non-removable media that can store information by any method or technology. The information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassette tapes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media, such as modulated data signals and carrier waves.

[0200] It should also be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, commodity or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, commodity or device. Without further limitation, an element defined by the statement "comprising one..." does not exclude the presence of additional identical elements in the process, method, commodity or device comprising the element.

[0201] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0202] 1), For the crack-type defect evaluation method of the hydrogen transmission pipeline of the present application, by selecting the steel pipe material of the same specification as the hydrogen transmission pipeline, determining the test conditions according to the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment, putting the tensile property and fracture toughness test specimens into the high-pressure gas-phase thermal hydrogen charging test equipment, carrying out the hydrogen charging test according to the test conditions, establishing a failure assessment curve, and using the pipeline defect detection technology for the hydrogen transmission pipeline to determine the defect situation, determining the evaluation points of the hydrogen transmission pipeline according to the defect situation, and when the evaluation points are in the non-safe area of the failure assessment curve, determining that the defects of the hydrogen transmission pipeline are unsafe and may cause cracking, then controlling to issue an alarm. The present application solves the technical problem in the prior art that the safety evaluation of the cracks caused by the hydrogen-induced cracking mechanism of the hydrogen transmission pipeline has not been realized to determine the safety of the hydrogen transmission pipeline.

[0203] 2), For the crack-type defect evaluation device of the hydrogen transmission pipeline of the present application, by selecting the steel pipe material of the same specification as the hydrogen transmission pipeline, determining the test conditions according to the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment, putting the tensile property and fracture toughness test specimens into the high-pressure gas-phase thermal hydrogen charging test equipment, carrying out the hydrogen charging test according to the test conditions, establishing a failure assessment curve, and using the pipeline defect detection technology for the hydrogen transmission pipeline to determine the defect situation, determining the evaluation points of the hydrogen transmission pipeline according to the defect situation, and when the evaluation points are in the non-safe area of the failure assessment curve, determining that the defects of the hydrogen transmission pipeline are unsafe and may cause cracking, then controlling to issue an alarm. The present application solves the technical problem in the prior art that the safety evaluation of the cracks caused by the hydrogen-induced cracking mechanism of the hydrogen transmission pipeline has not been realized to determine the safety of the hydrogen transmission pipeline.

[0204] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for evaluating crack-type defects in hydrogen pipelines, characterized in that, Including: Obtain the basic information of the hydrogen transmission pipeline, and select a material specimen according to the basic information, where the basic information includes pipeline material, pipeline diameter, pipeline wall thickness, and pipeline operating pressure; Determine the test conditions according to the basic information and the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment. The test conditions include test temperature, test pressure, and hydrogen absorption time. The hydrogen absorption time is the duration of hydrogen charging to the material specimen, and the hydrogen absorption time includes saturated hydrogen absorption time and unsaturated hydrogen absorption time; Under the test conditions, conduct tensile tests and fracture toughness tests on multiple groups of non-hydrogen-absorbing specimens and multiple groups of hydrogen-absorbing specimens respectively to obtain multiple tensile curves and multiple fracture toughnesses. The non-hydrogen-absorbing specimens are specimens that do not undergo hydrogen charging treatment on the material specimen, and the hydrogen-absorbing specimens are specimens that undergo hydrogen charging treatment on the material specimen. The tensile curve is the relationship curve between stress and strain of the material specimen under the action of tensile force; Based on the tensile curve and multiple fracture toughnesses at the saturated hydrogen absorption time, establish a failure assessment curve for the hydrogen transmission pipeline. The failure assessment curve is the relationship curve between the load ratio and the fracture ratio. The fracture ratio is the ratio of the stress intensity factor to the fracture toughness, and the load ratio is the ratio of the reference stress to the yield strength. The yield strength is the highest stress value before the first drop in the tensile curve; Use pipeline defect detection technology to detect crack-type defects in the hydrogen transmission pipeline and determine the evaluation points of the crack-type defects. The evaluation points are position coordinate points in the coordinate system where the failure assessment curve is located; When the ordinate of the evaluation point is greater than the ordinate of the corresponding failure assessment point, control the hydrogen transmission pipeline to stop running and send an alarm message. The failure assessment point is the point on the failure assessment curve with the same abscissa as the evaluation point. The alarm message is used to prompt that the hydrogen transmission pipeline is in an unsafe state due to crack-type defects and has a risk of cracking; 2. The method according to claim 1, characterized in that, Before establishing the failure assessment curve of the hydrogen transmission pipeline based on the tensile curve and multiple fracture toughnesses at the saturated hydrogen absorption time, the method further includes: Establish a first degradation model of the fracture toughness and the hydrogen absorption time according to multiple fracture toughnesses. The first degradation model is a degradation model used to characterize the linear relationship between the fracture toughness and the hydrogen absorption time. The input data of the first degradation model is the hydrogen absorption time, and the output data is the fracture toughness corresponding to the hydrogen absorption time; 3. The method according to claim 1, characterized in that, After establishing the failure assessment curve of the hydrogen transmission pipeline based on the tensile curve and multiple fracture toughnesses at the saturated hydrogen absorption time, the method further includes: Obtain multiple yield strengths and multiple tensile strengths through multiple tensile curves. Each tensile curve includes one yield strength and one tensile strength. The tensile strength is the corresponding maximum stress value in the tensile curve; Establish a second degradation model of the yield strength and the hydrogen absorption time based on multiple yield strengths. The second degradation model is used to characterize the degradation model of the linear relationship between the yield strength and the hydrogen absorption time. The input data of the second degradation model is the hydrogen absorption time, and the output data is the yield strength corresponding to the hydrogen absorption time; Establish a third degradation model of the tensile strength and the hydrogen absorption time based on multiple tensile strengths. The third degradation model is used to characterize the degradation model of the linear relationship between the tensile strength and the hydrogen absorption time. The input data of the third degradation model is the hydrogen absorption time, and the output data is the tensile strength corresponding to the hydrogen absorption time; Determine the saturated hydrogen absorption yield strength and the saturated hydrogen absorption tensile strength according to the second degradation model and the third degradation model respectively. The saturated hydrogen absorption yield strength is the yield strength when the hydrogen absorption time reaches the saturated hydrogen absorption time, and the saturated hydrogen absorption tensile strength is the tensile strength when the hydrogen absorption time reaches the saturated hydrogen absorption time; Calculate the cut-off value by taking the ratio of the sum of the strengths to twice the saturated hydrogen absorption yield strength. Draw a straight line perpendicular to the horizontal axis in the coordinate system according to the cut-off value and determine it as the cut-off line. The sum of the strengths is the sum of the saturated hydrogen absorption yield strength and the saturated hydrogen absorption tensile strength. The highest point of the cut-off line is the intersection point with the failure assessment curve. The area enclosed by the cut-off line, the failure assessment curve, the horizontal axis and the vertical axis is the safe area.

4. The method according to claim 3, characterized in that, Determine the saturated hydrogen absorption yield strength and the saturated hydrogen absorption tensile strength according to the second degradation model and the third degradation model respectively, including: In the case where the hydrogen absorption time of the second degradation model reaches the saturated hydrogen absorption time, determine the saturated hydrogen absorption yield strength according to the saturated hydrogen absorption time and the yield strength before hydrogen absorption; In the case where the hydrogen absorption time of the third degradation model reaches the saturated hydrogen absorption time, determine the saturated hydrogen absorption tensile strength according to the saturated hydrogen absorption time and the tensile strength before hydrogen absorption.

5. The method according to claim 3, characterized in that, Use pipeline defect detection technology to detect the defects of the hydrogen transmission pipeline and determine the evaluation points of the crack-type defects, including: Detect the hydrogen transmission pipeline using the pipeline defect detection technology to determine the defect length and the height of the defect itself; Substitute the saturated hydrogen absorption time and the minimum yield strength before hydrogen absorption into the second degradation model to calculate the minimum saturated hydrogen absorption yield strength; Substitute the saturated hydrogen absorption time and the minimum fracture toughness before hydrogen absorption into the third degradation model to calculate the minimum saturated hydrogen absorption fracture toughness; Substitute the defect length, the height of the defect itself and the basic information of the hydrogen transmission pipeline into the stress intensity factor formula and the reference stress formula respectively to calculate the stress intensity factor and the reference stress; Calculate the fracture ratio of the evaluation point according to the ratio of the stress intensity factor to the minimum saturated hydrogen absorption fracture toughness and calculate the load ratio of the evaluation point according to the ratio of the reference stress to the minimum saturated hydrogen absorption yield strength; Determine the evaluation point according to the load ratio and the fracture ratio.

6. The method according to claim 3, characterized in that, After detecting the defects of the hydrogen transmission pipeline by pipeline defect detection technology and determining the evaluation points of the crack-type defects, it includes: When the evaluation point is in the safe area, the hydrogen transmission pipeline operates normally and a prompt message is controlled to be sent. The prompt message is used to prompt that the defect of the hydrogen transmission pipeline is within the safe range and will not cause cracking.

7. The method according to claim 1, characterized in that, According to the basic information and the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment, determine the test conditions, including: According to the performance of the test equipment, determine the test temperature and the test pressure in the test conditions; Under the conditions of the test temperature and the test pressure, measure the change of the hydrogen content inside the material specimen with the hydrogen charging time, and determine the time threshold. The time threshold is the time point when the hydrogen content no longer changes with the hydrogen charging time; When the hydrogen charging time reaches the time threshold, determine the hydrogen charging time as the saturated hydrogen absorption time. The saturated hydrogen absorption time is the total time when the hydrogen content no longer changes with the hydrogen charging time; When the hydrogen charging time does not reach the time threshold, determine the hydrogen charging time as the unsaturated hydrogen absorption time.

8. A crack-type defect evaluation device for a hydrogen transmission pipeline, characterized in that, It includes: An acquisition unit for acquiring the basic information of the hydrogen transmission pipeline and selecting a material specimen according to the basic information. The basic information includes pipeline material, pipeline diameter, pipeline wall thickness, and pipeline operating pressure; A first determination unit for determining the test conditions according to the basic information and the requirements of the high-pressure gas-phase thermal hydrogen charging test equipment. The test conditions include test temperature, test pressure, and hydrogen absorption time. The hydrogen absorption time is the duration of hydrogen charging to the material specimen. The hydrogen absorption time includes saturated hydrogen absorption time and unsaturated hydrogen absorption time; A test unit for respectively performing tensile tests and fracture toughness tests on multiple groups of non-hydrogen-absorbing specimens and multiple groups of hydrogen-absorbing specimens under the test conditions to obtain multiple tensile curves and multiple fracture toughnesses. The non-hydrogen-absorbing specimen is a specimen that does not undergo hydrogen charging treatment on the material specimen, and the hydrogen-absorbing specimen is a specimen that undergoes hydrogen charging treatment on the material specimen. The tensile curve is the relationship curve between stress and strain of the material specimen under the action of tensile force; A first establishment unit for establishing a failure assessment curve of the hydrogen transmission pipeline based on the tensile curve and multiple fracture toughnesses under the saturated hydrogen absorption time. The failure assessment curve is the relationship curve between the load ratio and the fracture ratio. The fracture ratio is the ratio of the stress intensity factor to the fracture toughness, and the load ratio is the ratio of the reference stress to the yield strength. The yield strength is the highest stress value before the first drop in the tensile curve; A second determination unit for detecting the crack-type defects of the hydrogen transmission pipeline by pipeline defect detection technology and determining the evaluation points of the crack-type defects. The evaluation point is the position coordinate point in the coordinate system where the failure assessment curve is located; The first control unit is configured to control the hydrogen pipeline to stop operating and issue an alarm message when the ordinate of the evaluation point is greater than the ordinate of the corresponding failure evaluation point, where the failure evaluation point is the point on the failure evaluation curve with the same abscissa as the evaluation point, and the alarm message is used to indicate that the hydrogen pipeline is in an unsafe state due to crack-type defects and has a risk of cracking.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored program, wherein, when the program runs, it controls the device where the computer-readable storage medium is located to execute the method according to any one of claims 1 to 7.

10. A hydrogen transmission pipeline maintenance management system, characterized in that, Comprising: One or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include those for executing the method according to any one of claims 1 to 7.

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