Nuclear power plant BOSS head weld detection method, equipment and medium

Abstract

The present invention relates to the field of nuclear power plant maintenance optimization technology, and specifically to a method, device and medium for detecting welds of a BOSS head of a nuclear power plant, the method comprising: obtaining a radiographic detection result of a BOSS head of a nuclear power plant, the radiographic detection result being obtained by performing radiographic flaw detection and nondestructive testing on a preset weld area at the 0 degree position and the 180 degree position of the BOSS head of the nuclear power plant; when the radiographic detection result shows that a preset weld defect exists, performing phased array ultrasonic nondestructive testing on the BOSS head of the nuclear power plant to obtain weld defect information; when the weld mechanical evaluation result determined according to pipeline operation data and weld defect information shows that the performance is unqualified, performing a preset surfacing operation on the BOSS head of the nuclear power plant according to surfacing repair parameters. The present invention detects preset weld defects by combining radiographic flaw detection and nondestructive testing with phased array ultrasonic nondestructive testing, thereby improving the comprehensiveness and efficiency of defect detection, avoiding failure and leakage in the preset weld area of ​​the BOSS head of the nuclear power plant, and ensuring the safety of the nuclear power plant.

Description

Technical Field

[0001] The invention relates to the technical field of nuclear power plant maintenance optimization, and in particular to a nuclear power plant BOSS head weld detection method, equipment and medium. Background Art

[0002] A large number of BOSS heads (special nozzles for nuclear power plants) are used in the main circuit and secondary and tertiary component piping systems of nuclear power plants. The sizes vary widely and the structures are complex. The welds between the main pipe and the branch pipe of the BOSS head are subjected to the same temperature and pressure as the main pipe, which is prone to defects during manufacturing and operation. Failure and leakage in the preset weld area will seriously affect the safe operation of the nuclear power plant, especially since the primary system pipeline also contains radioactive media. The maintenance of the radioactive media after leakage is very difficult and the risk of contamination is high, which will seriously affect the overall overhaul period of the unit. Therefore, how to safely and effectively detect and repair defects in the preset weld area, and then ensure that the welds of the BOSS head will not fail and leak due to defects, is a problem that needs to be solved urgently. Summary of the invention

[0003] The embodiments of the present invention provide a nuclear power plant BOSS head weld detection method, device and medium, which can timely detect and repair defects in a preset weld area of ​​a nuclear power plant BOSS head, thereby avoiding failure and leakage in the preset weld area of ​​the nuclear power plant BOSS head.

[0004] The present invention provides a method for detecting a BOSS head weld of a nuclear power plant, comprising:

[0005] After receiving the nuclear power plant BOSS head detection instruction, the radiographic detection result of the nuclear power plant BOSS head is obtained, wherein the radiographic detection result is obtained by performing radiographic flaw detection and nondestructive testing on a preset weld area at the 0 degree position and the 180 degree position of the nuclear power plant BOSS head respectively; the nuclear power plant BOSS head comprises a main pipe and a branch pipe connected to the main pipe at a preset angle, and the preset weld area is connected between the main pipe and the branch pipe;

[0006] When the X-ray detection result shows that there is a preset weld defect, a phased array ultrasonic nondestructive test is performed on the BOSS head of the nuclear power plant to obtain weld defect information;

[0007] Acquire the pipeline operation data corresponding to the preset weld area, and determine the weld mechanics evaluation result of the BOSS head of the nuclear power plant according to the pipeline operation data and the weld defect information;

[0008] When the weld mechanics evaluation result is unqualified in performance, determining the surfacing repair parameters according to the weld mechanics evaluation result;

[0009] A preset surfacing operation is performed on the nuclear power plant BOSS head according to the surfacing repair parameters.

[0010] The present invention also provides a computer device, comprising a memory, a processor, and computer-readable instructions stored in the memory and executable on the processor, wherein the processor implements the above-mentioned nuclear power plant BOSS head weld detection method when executing the computer-readable instructions.

[0011] The present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer-readable instructions, and when the computer-readable instructions are executed by a processor, the above-mentioned nuclear power plant BOSS head weld detection method is implemented.

[0012] The nuclear power plant BOSS head weld detection method, device and medium provided by the present invention, after receiving the nuclear power plant BOSS head detection instruction, obtain the radiographic detection result of the nuclear power plant BOSS head, the radiographic detection result is obtained by performing radiographic flaw detection and nondestructive testing on the preset weld area at the 0 degree position and 180 degree position of the nuclear power plant BOSS head respectively; the nuclear power plant BOSS head includes a mother pipe and a branch pipe connected to the mother pipe at a preset angle, the preset weld area is connected between the mother pipe and the branch pipe; the 0 The 180-degree position is arranged relative to the 180-degree position and the axis of the mother pipe; when the X-ray detection result shows that there is a preset weld defect, the phased array ultrasonic non-destructive testing is performed on the BOSS head of the nuclear power plant to obtain weld defect information; the pipeline operation data corresponding to the preset weld area is obtained, and the weld mechanical evaluation result of the BOSS head of the nuclear power plant is determined according to the pipeline operation data and the weld defect information; when the weld mechanical evaluation result shows that the performance is unqualified, the surfacing repair parameters are determined according to the weld mechanical evaluation result; and the preset surfacing operation is performed on the BOSS head of the nuclear power plant according to the surfacing repair parameters.

[0013] The nuclear power plant BOSS head weld detection method of the present invention, after preliminarily determining that a preset weld defect exists in a preset weld area through radiographic nondestructive testing (RT), further obtains weld defect information corresponding to the preset weld defect through phased array ultrasonic nondestructive testing (PAUT), and then evaluates the weld mechanical evaluation result of the nuclear power plant BOSS head according to the weld defect information and the pipeline operation data of the preset weld area, and then determines whether the weld mechanical evaluation result is qualified in performance. That is, when the weld mechanical evaluation result is qualified in performance, it means that although the preset weld defect currently exists in the preset weld area of ​​the nuclear power plant BOSS head, its structural strength still meets the operation requirements of the nuclear power plant unit, and therefore will not cause risks such as failure and leakage. When the weld mechanical evaluation result is unqualified in performance, it will cause risks such as failure and leakage to the operation of the nuclear power plant BOSS head. At this time, the present invention will evaluate the preset weld area A preset surfacing operation is performed to promptly repair the preset weld area of ​​the BOSS head of the nuclear power plant, thereby avoiding failure and leakage in the preset weld area of ​​the BOSS head of the nuclear power plant and ensuring the safety of the nuclear power plant. At the same time, the present invention detects preset weld defects by combining radiographic nondestructive testing (RT) and phased array ultrasonic nondestructive testing (PAUT) (only preliminary testing is performed by radiographic nondestructive testing, which reduces the testing time and nuclear power plant radiation; since phased array ultrasonic nondestructive testing can detect information such as defect depth that cannot be determined by radiographic nondestructive testing, further testing by phased array ultrasonic nondestructive testing can improve the overall detection accuracy and efficiency of weld defects), thereby improving the comprehensiveness and efficiency of defect detection, reducing the possibility of irradiation, and improving personnel safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0015] Figure 1 is a flow chart of a method for detecting welds of a BOSS head in a nuclear power plant according to an embodiment of the present invention;

[0016] Figure 2 It is a cross-sectional schematic diagram of performing radiographic nondestructive testing of a preset weld area by using a nuclear power plant BOSS head weld detection method in one embodiment of the present invention;

[0017] Figure 3 It is a top view of a nuclear power plant BOSS head weld inspection method when performing radiographic nondestructive inspection on a preset weld area in one embodiment;

[0018] Figure 4 is a schematic diagram of a computer device in one embodiment of the present invention.

[0019] The reference numerals in the specification are as follows:

[0020] 11. Main tube; 12. Branch tube; 13. Radioactive source; 14. Film. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] In one embodiment, if Figure 1 As shown, a method for detecting a BOSS head weld in a nuclear power plant is provided, comprising the following steps S10-S50:

[0023] S10, after receiving the nuclear power plant BOSS head detection instruction, obtain the radiographic detection results of the nuclear power plant BOSS head, the radiographic detection results are obtained by performing radiographic nondestructive testing on the preset weld area at the 0 degree position and 180 degree position of the nuclear power plant BOSS head respectively; the nuclear power plant BOSS head includes a main pipe 11 and a branch pipe 12 connected to the main pipe 11 at a preset angle (the preset angle refers to the angle between the center axis of the main pipe 11 and the center axis of the branch pipe 12 on the plane constructed by the center axis of the main pipe 11 and the center axis of the branch pipe 12, and the preset angle is 90 degrees or less than 90 degrees), and the preset weld area is connected between the main pipe 11 and the branch pipe 12. The nuclear power plant BOSS head in the present invention is a reinforced transition design, the welding form between the branch pipe 12 and the main pipe 11 is a placement welding, and the preset weld area between the branch pipe 12 and the main pipe 11 is a full penetration fillet weld.

[0024] Among them, Figure 2 and Figure 3 As shown, the 0 degree position and the 180 degree position are relatively arranged, and the line between the 0 degree position and the 180 degree position is perpendicular to the axis of the busbar. In this way, by performing radiographic nondestructive testing on the preset weld area at the 0 degree position and the 180 degree position of the BOSS head of the nuclear power plant (film 14 is respectively arranged at the 0 degree position and the 180 degree position, and the weld defects are displayed on the film 14), a preliminary radiographic detection result can be obtained. The preliminary detection result can detect preset weld defects such as surface opening cracks in the preset weld area, but it is impossible to detect internal defects in the preset weld area, and it is impossible to determine the depth of the preset weld defects.

[0025] Furthermore, in the step S10, after obtaining the radiographic detection result of the BOSS head of the nuclear power plant, it also includes: when the radiographic detection result shows that there is no preset weld defect, sending normal detection information to the preset recipient, and the normal detection information is used to indicate that there is currently no preset weld defect in the weld area of ​​the BOSS head of the nuclear power plant. That is, when the radiographic detection result shows that there is no preset weld defect, it means that the preset weld area of ​​the BOSS head of the nuclear power plant does not have a preset weld defect such as a surface opening crack, and at this time, it only needs to continue to perform routine maintenance on it, and there is no need to enter step S20 for further detection, thereby improving the detection efficiency.

[0026] In a specific embodiment, any of the following situations is considered to be a predetermined weld defect:

[0027] a) Any form of cracks, lack of fusion, lack of penetration, undercut.

[0028] b) Any pore greater than 6 mm or e / 3, whichever is smaller, where e is the wall thickness.

[0029] c) Within the smaller length of 12e or 150mm, any strip of pores (or dense pores) with a combined diameter greater than e, if the distance between the two pores is less than 6 times the diameter of the smaller pore, they will be shown as the same strip (or the same dense) pore.

[0030] d) Any slag inclusion length (L) greater than the single slag inclusion given in Table 1 below.

[0031] Table 1 Comparison table of slag inclusion length and wall thickness

[0032]

[0033] e) In a weld with a length of 12e, the total length of the group of slag inclusions exceeds 2e. If the distance between two slag inclusions is less than 6 times the length of the longer one, the two slag inclusions are considered to be the same slag inclusion.

[0034] S20, when the result of the radiographic inspection is that there is a preset weld defect, the phased array ultrasonic nondestructive inspection is performed on the BOSS head of the nuclear power plant to obtain weld defect information; when the result of the radiographic inspection is that there is a preset weld defect, it indicates that the preset weld area of ​​the BOSS head of the nuclear power plant has a preset weld defect such as a surface open crack, and it will be necessary to consider whether to repair it. In some embodiments, when it is detected that the result of the radiographic inspection is that there is a preset weld defect, the preset weld defect can be directly repaired by digging, rewelding or replacing. However, it is understandable that in some systems of nuclear power plants, such as the PTR (reactor and spent fuel pool cooling and treatment system) system or the RRI (equipment cooling water system) system, after a preset weld defect is detected in the preset weld area of ​​the BOSS head of the nuclear power plant, if the repair is directly carried out by means of patching, rewelding or replacement, the system needs to be temporarily shut down and partially isolated, which will cause the corresponding cooling function of the nuclear power plant to be lost and the temperature of the spent fuel pool to rise. In order to ensure the safety of the nuclear power plant, the water filling must be restored before the temperature of the spent fuel pool exceeds the operating limit. Since the time interval between filling and draining (that is, the repair time that can be used for repair) is short, the patching, rewelding or replacement operation cannot be completed. Therefore, in the present invention, it is necessary to use cladding repair for repair treatment, but before performing cladding repair, it is necessary to first perform a mechanical property evaluation to obtain a weld mechanical evaluation result (because weld defect data must be used in the process of mechanical property evaluation, including data such as weld depth, and the X-ray detection results obtained by X-ray nondestructive testing cannot determine the depth of the preset weld defect, etc., therefore, in step S20 of the present invention, it is necessary to first use phased array ultrasonic nondestructive testing for further testing to obtain the weld defect data needed for the mechanical property evaluation process), so as to determine whether the weld mechanical evaluation result is qualified, and then determine whether cladding repair treatment is needed.

[0035] S30, obtaining the pipeline operation data corresponding to the preset weld area, and determining the weld mechanical evaluation result of the BOSS head of the nuclear power plant according to the pipeline operation data and the weld defect information; that is, in this step, the pipeline operation data includes but is not limited to the main pipeline parameters, material parameters, operation acquisition data, etc. The pipeline operation data has been collected and stored in the database during the manufacturing and operation process of the BOSS head of the nuclear power plant, so that it can be retrieved from the database at any time when needed. In this step, the above-mentioned pipeline operation data is directly retrieved from the database, and then the mechanical properties are evaluated according to the weld defect information and pipeline operation data collected by the phased array ultrasonic nondestructive testing (PAUT) to obtain the weld mechanical evaluation result of the BOSS head of the nuclear power plant.

[0036] In one embodiment, after determining the weld mechanical evaluation result of the nuclear power plant BOSS head according to the pipeline operation data and the weld defect information, it also includes: when the weld mechanical evaluation result is qualified in performance, determining the in-service monitoring plan according to the weld mechanical evaluation result, and performing in-service monitoring operations on the nuclear power plant BOSS head according to the in-service monitoring plan. Specifically, when the weld mechanical evaluation result is qualified in performance, it means that although there are preset weld defects in the preset weld area of ​​the nuclear power plant BOSS head, its structural strength still meets the operating requirements of the nuclear power plant unit, so it will not cause risks such as failure and leakage, and there is no need to perform surfacing repair temporarily. Therefore, at this time, only the nuclear power plant BOSS head needs to be monitored in service. Among them, the in-service monitoring operation is specifically set according to actual needs, for example, both visual inspection and ray-assisted monitoring are possible, and its detection cycle is also set according to demand. S40, when the weld mechanical evaluation result is unqualified in performance, determine the surfacing repair parameters according to the weld mechanical evaluation result; specifically, when the weld mechanical evaluation result is unqualified in performance, it will cause risks such as failure and leakage to the operation of the BOSS head of the nuclear power plant. At this time, it is necessary to perform a preset surfacing operation on the preset weld area to repair the preset weld area of ​​the BOSS head of the nuclear power plant in time, avoid failure and leakage in the preset weld area of ​​the BOSS head of the nuclear power plant, and ensure the safety of the nuclear power plant.

[0037] Among them, the surfacing welding repair parameters for the preset surfacing welding operation on the BOSS head of the nuclear power plant include but are not limited to the number of surfacing welding layers and the water-pressure surfacing welding parameters corresponding to each of the surfacing welding layers; the water-pressure surfacing welding parameters include welding material parameters, power polarity, welding current parameters, pulse frequency, duty cycle, tungsten electrode diameter, arc voltage, welding speed, maximum heat input and interlayer temperature, etc. In the present invention, the water-pressure surfacing welding operation is performed through the following specific surfacing welding repair parameters, which can make the final leakage test results more stable and reliable:

[0038] When the number of surfacing layers is the first layer, the water- and pressure-resistant surfacing parameters corresponding to the first layer include: the welding material diameter in the welding material parameters is 1.6 mm; the power supply polarity is reverse DC; the peak value of the welding current parameter is 90 V, and the base value is 70 A; the pulse frequency is 2.0 Hz; the duty cycle is 60%; the tungsten electrode diameter is 2.4; the arc voltage is 9 to 12 V; the welding speed is 32 to 71 mm / min; the maximum heat input is 1400 J / mm; and the interlayer temperature is less than or equal to 100°C.

[0039] When the number of surfacing layers is the second layer, the water- and pressure-resistant surfacing parameters corresponding to the second layer include: the welding material diameter in the welding material parameters is 1.6 mm; the power supply polarity is reverse DC; the peak value of the welding current parameter is 100 V, and the base value is 75 A; the pulse frequency is 2.0 Hz; the duty cycle is 60%; the tungsten electrode diameter is 2.4; the arc voltage is 9 to 12 V; the welding speed is 32 to 54 mm / min; the maximum heat input is 1800 J / mm; and the interlayer temperature is less than or equal to 100°C.

[0040] When the number of surfacing layers is one of the third to fifth layers, the corresponding water- and pressure-based surfacing parameters include: the welding material diameter in the welding material parameters is 1.6 mm; the power supply polarity is reverse DC; the peak value of the welding current parameter is 100 V, and the base value is 75 A; the pulse frequency is 2.0 Hz; the duty cycle is 60%; the tungsten electrode diameter is 2.4; the arc voltage is 9 to 12 V; the welding speed is 20 to 60 mm / min; the maximum heat input is 2000 J / mm; and the interlayer temperature is less than or equal to 100°C.

[0041] When the number of surfacing layers is one of the sixth to seventh layers, the corresponding water- and pressure-based surfacing parameters include: the welding material diameter in the welding material parameters is 1.6 mm; the power supply polarity is reverse DC; the peak value of the welding current parameter is 105 V, and the base value is 85 A; the pulse frequency is 2.0 Hz; the duty cycle is 60%; the tungsten electrode diameter is 2.4; the arc voltage is 9 to 12 V; the welding speed is 20 to 60 mm / min; the maximum heat input is 2200 J / mm; and the interlayer temperature is less than or equal to 100°C.

[0042] S50, performing a preset surfacing operation on the BOSS head of the nuclear power plant according to the surfacing repair parameters. That is, in this embodiment, the BOSS head of the nuclear power plant is subjected to water and pressure surfacing repair operations according to the above-mentioned surfacing repair parameters, so as to achieve the repair of the above-mentioned preset weld defects. The surfacing repair reduces the repair difficulty and repair time, ensures the overall construction period of the nuclear power plant unit overhaul, and further ensures the safe operation of the nuclear power plant. It is understandable that after the surfacing repair operation is completed, the surface of the surfacing layer of the BOSS head of the nuclear power plant needs to be polished. If the material of the BOSS head of the nuclear power plant is a carbon steel pipe, it also needs to be painted. Among them, the preset surfacing operation preferably adopts TIG (Tungsten Inert Gas Welding, non-melting inert gas shielded arc welding) surfacing.

[0043] In one embodiment, after performing a preset surfacing operation on the nuclear power plant BOSS head according to the surfacing repair parameters, the method further includes:

[0044] The phased array ultrasonic nondestructive testing is performed again on the nuclear power plant BOSS head to obtain the surfacing repair defect information corresponding to the surfacing layer after the nuclear power plant BOSS head performs the preset surfacing operation; specifically, the above-mentioned process of performing phased array ultrasonic nondestructive testing can refer to the process of obtaining weld defect data in step S20 in the context of the present invention, which will not be repeated here. When it is determined according to the surfacing repair defect information that there is a preset weld defect in the surfacing layer after the nuclear power plant BOSS head performs the preset surfacing operation, it means that the surfacing operation is not successful, and the preset weld area of ​​the nuclear power plant BOSS head will need to be processed in other ways, such as continuing the next surfacing or grinding and repairing the surfacing layer, replacing the nuclear power plant BOSS head, etc.

[0045] When the preset weld defect is not included in the surfacing repair defect information, the surfacing repair of the preset weld area is confirmed to be qualified. That is, after confirming that the surfacing repair is qualified, the in-service monitoring operation of the nuclear power plant BOSS head can be continued. Among them, the in-service monitoring operation is set according to actual needs. For example, both visual inspection and radiation-assisted monitoring are possible, and the inspection cycle is also set according to demand. For example, the time for visual inspection includes the first refueling overhaul and the second refueling overhaul after the surfacing repair operation. If no abnormality is found in the two inspections, it is modified to be inspected every ten years, otherwise the inspection cycle is shortened. The radiation-assisted monitoring is during the first refueling overhaul and the second refueling overhaul after the surfacing repair operation and the tenth year. If no abnormality is found in the three inspections, the inspection can be cancelled, otherwise the inspection cycle is shortened.

[0046] The nuclear power plant BOSS head weld detection method of the present invention, after preliminarily determining that a preset weld defect exists in a preset weld area through radiographic nondestructive testing (RT), further obtains weld defect information corresponding to the preset weld defect through phased array ultrasonic nondestructive testing (PAUT), and then evaluates the weld mechanical evaluation result of the nuclear power plant BOSS head according to the weld defect information and the pipeline operation data of the preset weld area, and then determines whether the weld mechanical evaluation result is qualified in performance. That is, when the weld mechanical evaluation result is qualified in performance, it means that although the preset weld defect currently exists in the preset weld area of ​​the nuclear power plant BOSS head, its structural strength still meets the operation requirements of the nuclear power plant unit, and therefore will not cause risks such as failure and leakage. When the weld mechanical evaluation result is unqualified in performance, it will cause risks such as failure and leakage to the operation of the nuclear power plant BOSS head. At this time, the present invention will evaluate the preset weld area A preset surfacing operation is performed to promptly repair the preset weld area of ​​the BOSS head of the nuclear power plant, thereby avoiding failure and leakage in the preset weld area of ​​the BOSS head of the nuclear power plant and ensuring the safety of the nuclear power plant. At the same time, the present invention detects preset weld defects by combining radiographic nondestructive testing (RT) and phased array ultrasonic nondestructive testing (PAUT) (only preliminary testing is performed by radiographic nondestructive testing, which reduces the testing time and nuclear power plant radiation; since phased array ultrasonic nondestructive testing can detect information such as defect depth that cannot be determined by radiographic nondestructive testing, further testing by phased array ultrasonic nondestructive testing can improve the overall detection accuracy and efficiency of weld defects), thereby improving the comprehensiveness and efficiency of defect detection, reducing the possibility of irradiation, and improving personnel safety.

[0047] In one embodiment, the preset weld area includes a root weld connecting the mother pipe 11, a top weld connecting the branch pipe 12, and a main weld connecting the root weld and the top weld; further, in step S20, performing phased array ultrasonic nondestructive testing on the BOSS head of the nuclear power plant to obtain weld defect information includes:

[0048] The phased array probe is controlled to scan the main body weld from the side of the mother tube 11 to obtain a first detection waveform of the main body weld; it can be understood that when the phased array probe scans the main body weld from the side of the mother tube 11, the detection wave of the phased array probe is irradiated to the main body weld from the side of the mother tube 11 and scans it, and then the first detection waveform of the main body weld can be obtained through a detector, etc.

[0049] The phased array probe is controlled to scan the root weld of the preset weld area from the first position point on the side of the branch pipe 12 to obtain a second detection waveform of the root weld area; it can be understood that when the phased array probe scans the root weld of the preset weld area from the first position point on the side of the branch pipe 12, the detection wave of the phased array probe is irradiated from the first position point on the side of the branch pipe 12 to the root weld and scans it, and then the second detection waveform of the root weld can be obtained through a detector, etc. Among them, the first position point refers to any position point on the ring of the branch pipe 12 that is a first distance away from the main pipe 11.

[0050] The phased array probe is controlled to scan the top weld of the preset weld area from the second position point on the side of the branch pipe 12 to obtain the third detection waveform of the top weld; it can be understood that when the phased array probe scans the top weld of the preset weld area from the second position point on the side of the branch pipe 12, the detection wave of the phased array probe is irradiated from the second position point on the side of the branch pipe 12 to the top weld and scans it, and then the third detection waveform of the top weld can be obtained through a detector, etc. Wherein, the second position point refers to any position point on the ring of the branch pipe 12 that is a second distance away from the main pipe 11, and the distance between the second position point and the main pipe 11 is greater than the distance between the first position point and the main pipe 11, that is, the second distance is greater than the first distance.

[0051] Obtain a preset comparison waveform, compare the preset comparison waveform with the first detection waveform, the second detection waveform and the third detection waveform respectively, and determine the first defect value of the main body weld, the second defect value of the root weld area, and the third defect value of the top weld; it can be understood that the preset comparison waveform can be a comparison waveform parameter pre-stored in a database. Further, the first defect value characterizes the defect of the main body weld (crack size and depth, etc.), the second defect value characterizes the defect of the root weld (crack size and depth, etc.), and the third defect value characterizes the defect of the top weld (crack size and depth, etc.). Specifically, the amplitude, peak value, etc. of the first detection waveform are compared with the preset comparison wave respectively, so that the one defect value can be confirmed; the confirmation of the second defect value and the third defect value is the same as the confirmation of the first defect value, which will not be repeated here.

[0052] The weld defect information of the BOSS head of the nuclear power plant is determined according to the first defect value, the second defect value, and the third defect value. It can be understood that the weld defect information includes the first defect value, the second defect value, and the third defect value, and the first defect value includes the depth and shape of the defect in the main weld, the second defect value includes the depth and shape of the defect in the root weld, and the third defect value includes the depth and shape of the defect in the top weld. The above embodiment improves the detection accuracy of the BOSS head of the nuclear power plant, and facilitates the subsequent mechanical property evaluation and surfacing repair operations of the BOSS head of the nuclear power plant according to the weld defect information.

[0053] In one embodiment, controlling the phased array probe to scan the main body weld from the side of the mother pipe 11 to obtain a first detection waveform of the main body weld includes:

[0054] The phased array probe is controlled to scan the main body weld from the side of the mother tube 11 at the 0 degree position, 90 degree position, 180 degree position and 270 degree position of the BOSS head of the nuclear power plant, respectively, to obtain four main body waveforms corresponding to four directions, respectively, and the first detection waveform of the main body weld is determined according to the four main body waveforms; it can be understood that the 0 degree position, 90 degree position, 180 degree position and 270 degree position are four positions distributed at equal angles around the mother tube 11. Since the detection wave emitted by the phased array probe can detect the main body weld in a certain fan-shaped area, the main body weld is scanned from the 0 degree position, 90 degree position, 180 degree position and 270 degree position of the mother tube 11 side, respectively, so as to detect the entire main body weld, thereby improving the detection accuracy and detection efficiency of the main body weld.

[0055] Further, controlling the phased array probe to scan the root weld of a preset weld area from a first position point on the side of the branch pipe 12 to obtain a second detection waveform of the root weld area includes:

[0056] The phased array probe is controlled to scan the root weld from the first position point on the side of the branch pipe 12 at the 0 degree position, 90 degree position, 180 degree position and 270 degree position of the BOSS head of the nuclear power plant, respectively, to obtain four root waveforms corresponding to four directions, and the second detection waveform of the root weld is determined according to the four root waveforms; since the detection wave emitted by the phased array probe detects the root weld in a certain fan-shaped area, the root weld is scanned from the first position points (the first position point refers to any position point on the branch pipe 12 on the ring with a first distance from the main pipe 11) corresponding to the 0 degree position, 90 degree position, 180 degree position and 270 degree position on the side of the branch pipe 12, thereby detecting the entire root weld, thereby improving the detection accuracy and detection efficiency of the root weld.

[0057] Further, the controlling the phased array probe to scan the top weld of the preset weld area from the second position point on the side of the branch pipe 12 to obtain a third detection waveform of the top weld includes:

[0058] The phased array probe is controlled to scan the top weld from the second position point on the side of the branch pipe 12 at the 0 degree position, 90 degree position, 180 degree position and 270 degree position of the BOSS head of the nuclear power plant, respectively, to obtain four top waveforms corresponding to four directions, and the third detection waveform of the top weld is determined according to the four top waveforms. Since the detection wave emitted by the phased array probe detects the top weld in a certain fan-shaped area, the top weld is scanned from the second position point (the second position point refers to any position point on the ring on the branch pipe 12 that is a second distance away from the main pipe 11) corresponding to the 0 degree position, 90 degree position, 180 degree position and 270 degree position on the side of the branch pipe 12, thereby detecting the entire top weld, thereby improving the detection accuracy and detection efficiency of the top weld.

[0059] In one embodiment, the preset comparison waveform includes a first comparison waveform; the first defect value includes a first depth value, the second defect value includes a second depth value, and the third defect value includes a third depth value; it can be understood that the first depth value represents the depth of the defect in the main weld from the outer surface of the main weld, the second depth value represents the depth of the defect in the root weld from the outer surface of the root weld, and the third depth value represents the depth of the defect in the top weld from the outer surface of the top weld 333.

[0060] Furthermore, before obtaining the preset comparison waveform, the method includes:

[0061] Control the phased array probe to scan a preset square comparison block to obtain the first pair of preset comparison waveforms; wherein, the preset square comparison block is provided with a plurality of first comparison defect holes distributed in a stepped manner; the first pair of preset comparison waveforms characterizes the depth of the first comparison defect holes in the preset square comparison block; it can be understood that the distances between the plurality of first comparison defect holes and the upper surface of the preset square comparison block are not equal, and the phased array probe is scanned from the upper surface of the preset square comparison block to the first comparison defect holes. Since the distances between different first defect holes and the upper surface of the preset square comparison block are not equal, the amplitudes and other characteristics of the first comparison waveforms corresponding to them are also different, and therefore the first comparison waveforms with different amplitudes and other characteristics characterize the first comparison defect holes of different depths.

[0062] Further, the preset comparison waveform is compared with the first detection waveform, the second detection waveform and the third detection waveform respectively to determine the first defect value of the main weld, the second defect value of the root weld area, and the third defect value of the top weld, including:

[0063] The first comparison waveform is compared with the first detection waveform to determine the first depth value; it can be understood that by comparing the amplitude of the first detection waveform with the amplitudes of multiple first comparison waveforms, the first depth value can be determined, that is, the depth of the defect in the main weld from the outer surface of the main weld can be determined.

[0064] The first comparison waveform is compared with the second detection waveform to determine the second depth value; it can be understood that by comparing the amplitude of the second detection waveform with the amplitudes of multiple first comparison waveforms, the second depth value can be determined, that is, the depth of the defect in the root weld from the outer surface of the root weld can be determined.

[0065] The first comparison waveform is compared with the third detection waveform to determine the third depth value. It can be understood that by comparing the amplitude of the third detection waveform with the amplitudes of the plurality of first comparison waveforms, the third depth value can be determined, that is, the depth of the defect in the top weld from the outer surface of the top weld can be determined.

[0066] In one embodiment, the preset square comparison test block is provided with an arc surface, and the phased array probe scans the first comparison defect hole from the arc surface; preferably, the radius of curvature R of the arc surface is greater than or equal to 10 mm (for example, 12.5 mm, 15 mm, 20 mm, and 25 mm, etc.). Specifically, the design of the arc surface allows the waveform reflected from the first comparison defect hole to pass through the arc surface and enter the receiving center of the phased array probe, thereby improving the accuracy and precision of the nuclear power plant BOSS head weld. Furthermore, the preset square comparison test block can be set to multiple according to actual needs, and different preset square comparison test blocks (materials, sizes, etc. will be adaptively changed according to changes in the nuclear power plant BOSS head) can be used for comparison for different nuclear power plant BOSS heads. In this embodiment, through the design of the preset square comparison test block and its waveform comparison, the depth of the defect in the preset weld area can be accurately obtained.

[0067] In one embodiment, the preset comparison waveform includes a second comparison waveform; the first defect value includes a first shape value; the second defect value includes a second shape value; the third defect value includes a third shape value; it can be understood that the first shape value characterizes the shape of the defect in the main weld (circular cracks, long cracks, pores, main weld is not melted, etc.); the second shape value characterizes the shape of the defect in the root weld (circular cracks, long cracks, pores, root weld is not melted, etc.) The third shape value characterizes the shape of the defect in the top weld (circular cracks, long cracks, pores, top weld is not melted, etc.).

[0068] Furthermore, before obtaining the preset comparison waveform, the method includes:

[0069] Control the phased array probe to scan the preset pipeline comparison test block to obtain a second comparison waveform; wherein the preset pipeline comparison test block is consistent with the material and size of the nuclear power plant BOSS head, and the preset pipeline comparison test block includes a comparison mother pipe and a comparison branch pipe, and the comparison branch pipe is welded to the comparison mother pipe through a comparison weld area; a plurality of comparison defect hole groups are provided in the comparison weld area; it can be understood that the preset pipeline comparison test block simulates the setting of the nuclear power plant BOSS head, the comparison mother pipe is equivalent to the mother pipe 11, the comparison branch pipe is equivalent to the branch pipe 12, the comparison weld area is equivalent to the preset weld area, and the defect hole group simulates the defects in the preset weld area, and each of the comparison defect hole groups includes a plurality of comparison defect holes. Further, the preset comparison waveform is compared with the first detection waveform, the second detection waveform and the third detection waveform respectively to determine the first defect value of the main weld, the second defect value of the root weld area, and the third defect value of the top weld, including:

[0070] The first comparison waveform is compared with the first detection waveform to determine the first shape value; it can be understood that the first shape value can be determined by comparing the peak value, position, etc. of the first detection waveform with the corresponding features of multiple second comparison waveforms.

[0071] The first comparison waveform is compared with the second detection waveform to determine the second shape value; it can be understood that the second shape value can be determined by comparing the peak value, position, etc. of the second detection waveform with the corresponding features of multiple second comparison waveforms.

[0072] The first comparison waveform is compared with the third detection waveform to determine the third shape value. It can be understood that the third shape value can be determined by comparing the peak value, position, etc. of the third detection waveform with the corresponding features of the plurality of second comparison waveforms.

[0073] In this embodiment, through the design of the preset pipeline comparison test block, the shape and position of the defect in the preset weld area can be accurately detected, which is convenient for subsequent surfacing treatment of the preset weld area.

[0074] In one embodiment, the defect hole group includes a plurality of second comparison defect holes arranged in the comparison weld area at a 0 degree position, a plurality of third comparison defect holes arranged in the comparison weld area at a 90 degree position, a plurality of fourth comparison defect holes arranged in the comparison weld area at a 180 degree position, and a plurality of fifth comparison defect holes arranged in the comparison weld area at a 270 degree position. It can be understood that the second comparison defect hole, the third comparison defect hole, the fourth comparison defect hole, and the fifth comparison defect hole can be respectively set to different sizes and / or shapes, and they can all include but are not limited to comparison defect holes such as circular cracks, long strip cracks, pores, and unmelted main welds.

[0075] Further, the present invention can install the phased array probe on the comparison branch pipe from the 0 degree position, 90 degree position, 180 degree position and 270 degree position of the comparison branch pipe side, respectively, and the phased array probe can scan the comparison weld area at the corresponding position, so as to obtain the second comparison waveform. In this embodiment, multiple comparison defect holes are set at the 0 degree position, 90 degree position, 180 degree position and 270 degree position of the comparison weld area, and the angle between the central axis of the comparison branch pipe and the central axis of the comparison mother pipe is an acute angle. The second comparison waveform detected in different directions and the second comparison waveform at different positions can be compared with the first detection waveform to obtain the position of the defect in the main weld; the position of the defect in the root weld can be obtained by comparing the second comparison waveform at different positions with the second detection waveform, and the position of the defect in the top weld can be obtained by comparing the second comparison waveform at different positions with the third detection waveform, that is, the spatial position of the defect in the preset weld area can be obtained.

[0076] In one embodiment, the step of determining the weld mechanics evaluation result of the BOSS head of the nuclear power plant according to the pipeline operation data and the weld defect information includes:

[0077] Obtain model constraints of the nuclear power plant BOSS head; wherein the model constraints are constraints or rules for constructing a thermal stress model and constraints or rules for constructing a mechanical load model that are pre-set according to requirements, and the model constraints include the thermal stress model constraints and the mechanical load model constraints, the thermal stress model constraints are constraints or rules for constructing a thermal stress model, and the mechanical load model constraints are constraints or rules for constructing a mechanical load model.

[0078] The BOSS head area model is generated according to the main pipeline parameters and the weld defect information in the pipeline operation data; the pipeline operation data includes a three-dimensional model, main pipeline parameters, material parameters, BOSS pipeline radius value and BOSS pipeline wall thickness value, the three-dimensional model is a three-dimensional model constructed of the main pipeline, BOSS pipeline and the preset weld area, the main pipeline parameters are parameters related to the main pipeline connected to the BOSS head of the nuclear power plant, the material parameters are parameters related to the materials of the main pipeline and the BOSS pipeline, the BOSS pipeline radius value is the inner diameter of the BOSS pipeline, and the BOSS pipeline wall thickness value is the wall thickness of the BOSS pipeline. The above pipeline operation data can be used to construct the main structure of the BOSS head area model, and the weld defect information is used to construct the preset weld defects in the BOSS head area model.

[0079] It can be understood that the main pipeline parameters include the mean value of the main pipeline radius and the main pipeline wall thickness value. The mean value of the main pipeline radius is the average radius value of the main pipeline connected to the BOSS head of the nuclear power plant, and the main pipeline wall thickness value is the wall thickness of the main pipeline connected to the BOSS head of the nuclear power plant. The interception length function is used to calculate and output the interception length. The interception length is the length of the main pipeline in the three-dimensional model selected from the finite element modeling data, so that the main pipeline outside the interception length is basically no longer affected by the stress caused by the discontinuity effect after the BOSS head of the nuclear power plant is connected. The BOSS head area model can be selected from the three-dimensional model through the interception length. The BOSS head area model is a three-dimensional area intercepted from the three-dimensional model by a cube with the interception length as the side length.

[0080] According to the model constraints and the material parameters and operation acquisition data in the pipeline operation data, the temperature field analysis, thermal stress analysis and mechanical load analysis are performed on the BOSS head area model to obtain stress results;

[0081] It can be understood that the material parameters are parameters related to the materials of the main pipeline and the BOSS pipeline, and the material parameters include the main pipeline material parameters and the BOSS pipeline material parameters. The main pipeline material parameters are the material model of the main pipeline, for example: the main pipeline material parameter is X2 CrNi 19.10, X2 CrNi 19.10 is a model of a stainless steel pipe, and the BOSS pipeline material parameters are the material model of the BOSS pipeline, for example: the BOSS pipeline material parameter is Z2 CND 18-12NC, Z2 CND18-12NC is the model of a stainless steel pipe used for reactor coolant system pipelines. The operation collection data is transient temperature data, thermal stress data and mechanical load stress data of each time point historically collected during the operation of the main pipeline and the BOSS pipeline. The operation collection data includes a temperature field cloud map, a thermal stress field cloud map and a mechanical load stress field cloud map. The temperature field cloud map is a distribution map of the temperature changes of each point in the BOSS head area model over time, that is, the temperature distribution and changes of the BOSS head area model over time can be seen through the temperature field cloud map. The thermal stress field cloud map is a distribution map of the thermal stress changes of each point in the BOSS head area model over time, that is, the thermal stress distribution and changes of the BOSS head area model over time can be seen through the thermal stress field cloud map. The mechanical load stress field cloud map is a distribution map of the mechanical load stress borne by each point on the inner wall of the BOSS head area model over time, that is, the changes of the mechanical load stress borne by the inner wall of the BOSS head area model over time can be seen through the mechanical load stress field cloud map.

[0082] The temperature field analysis process is to obtain the transient temperature field data of each evaluation path from the temperature field cloud map in the operation collection data, and to draw the transient temperature field curve corresponding to each evaluation path. The thermal stress analysis process is to obtain the transient thermal stress field data of each evaluation path from the thermal stress field cloud map in the operation collection data, and to draw the transient thermal stress field curve corresponding to each evaluation path. The mechanical load analysis process is to obtain the transient mechanical load stress field data of each evaluation path from the mechanical load stress field cloud map in the operation collection data, and to draw the transient mechanical load stress field curve corresponding to each evaluation path. The process of evaluating the mechanical load stress curve, the evaluation path is the path output after the evaluation path identification, the process of evaluating the path identification is to find a set of path nodes that overlap and are in the weld vicinity in the constructed temperature field model, the thermal stress field model and the mechanical load stress model, the weld vicinity is a three-dimensional area enclosed by a preset distance extending from the BOSS head welding point, all the transient temperature field curves, all the transient thermal stress curves and all the transient mechanical load stress curves are summarized, so as to determine the stress result, which reflects the stress distribution of the temperature field, thermal stress field and mechanical load stress field on each evaluation path.

[0083] Using stress intensity factor analysis method, fatigue crack growth and stress corrosion crack growth are performed on the stress results to obtain crack evaluation results;

[0084] It can be understood that the stress intensity factor analysis method is a method of performing polynomial fitting on the stress perpendicular to the crack surface on the wall thickness of the BOSS tube at the location of the crack, and then using the stress intensity factor function to calculate the stress intensity factor of the crack. The fatigue crack extension is an extension method for estimating the fatigue life of the crack according to the fatigue crack extension rate, and the fatigue extension rate is related to the material parameters and stress intensity factor of the BOSS tube. The stress corrosion crack extension is an extension method for estimating the crack corrosion life according to the stress corrosion extension rate, and the stress corrosion crack extension rate is related to the material parameters and stress intensity factor of the BOSS tube. Fatigue crack extension and stress corrosion crack extension are performed on the circumferential crack area to obtain a circumferential crack evaluation result, and fatigue crack extension and stress corrosion crack extension are performed on the axial crack area to obtain an axial crack evaluation result. The crack evaluation result includes the circumferential crack evaluation result and the axial crack evaluation result, and the crack evaluation result combines the evaluation results of the circumferential crack evaluation result and the axial crack evaluation result.

[0085] The crack evaluation results are subjected to fracture analysis, and weld mechanics evaluation results corresponding to the BOSS head of the nuclear power plant are output.

[0086] It can be understood that the fracture analysis is a process of analyzing the evaluation results of the circumferential crack and the evaluation results of the axial crack, that is, on the one hand, the analysis of the evaluation results of the circumferential crack is to analyze and evaluate the circumferential crack area of ​​the BOSS head to be evaluated, and the crack extension is located on the 90° section. If the length of the initial circumferential crack is 5mm, the crack extension at the end of 40 years of life is 3.0984mm, and the final crack length at the end of the life is 8.0984mm. At the end of the life, a=8.0984mm, and its stress intensity factor is much smaller than the material toughness of the BOSS pipeline. Therefore, for the circumferential crack, the structure will not fracture rapidly; on the other hand, the analysis of the evaluation results of the axial crack is to analyze and evaluate the axial crack area of ​​the BOSS head of the nuclear power plant, and the crack extension is located on the 90° section. If the length of the initial circumferential crack is 5mm, the crack depth at the end of the 9th year is 14.4962mm, and its stress intensity factor is less than the material toughness, and 14.4962mm It has exceeded 0.75 times (17.8×0.75=13.35 mm) the wall thickness of the BOSS pipe (17.8 mm), and the structure may fail due to plastic collapse, resulting in the risk of coolant leakage.

[0087] Among them, the circumferential crack evaluation results and the axial crack evaluation results in the crack evaluation results are comprehensively analyzed, and the ratio of the length and depth of crack extension at the same time point and the year of the risk of fracture are compared, and the weld mechanics evaluation results of the BOSS head of the nuclear power plant are output. According to the weld mechanics evaluation results, the measures for patching or replacement of the BOSS head of the nuclear power plant are displayed in which year.

[0088] The present invention realizes the automatic processing of steps such as stress analysis, stress extraction, assumed cracks, stress intensity factor output, crack mechanics analysis, etc. according to the actual working conditions of the nuclear power plant through finite element modeling data, quickly completes the fracture analysis, and objectively outputs the weld mechanics evaluation results of the preset weld defects in the preset weld area, determines its stability during the nuclear power plant refueling cycle or the entire service life of the nuclear power plant, and further provides a reference for whether it needs to be subjected to surfacing treatment.

[0089] In one embodiment, the temperature field analysis, thermal stress analysis and mechanical load analysis are performed on the BOSS head area model according to the model constraints and the material parameters and operation acquisition data in the pipeline operation data to obtain stress results, including:

[0090] According to the material parameters and the model constraints, the BOSS head region model is divided into multi-dimensional structural units to divide the temperature field model, the thermal stress field model and the mechanical load stress model;

[0091] It can be understood that the multi-dimensional structural unit division is a different division method for constructing a three-dimensional solid structure. The multi-dimensional structural unit division includes unit divisions such as SOLID45, SOLID70, SOLID185 and SOLID285 in the ANSYS simulation tool software. Through the multi-dimensional structural unit division, the BOSS head area model can be divided into three-dimensional models of different dimensions. From the multi-dimensional structural unit division, a unit division method suitable for the temperature field, thermal stress field and mechanical load stress field is selected. For example: the SOLID70 unit division is used to divide the BOSS head area model to obtain a temperature field model, the SOLID185 unit division is used to divide the BOSS head area model to obtain a thermal stress model, and the SOLID185 unit division is used to divide the BOSS head area model to obtain a mechanical load stress model.

[0092] Performing assessment path identification on the temperature field model, the thermal stress field model, and the mechanical load stress model to identify a plurality of assessment paths;

[0093] It can be understood that the process of identifying the assessment path is to find a set of path nodes that overlap and are located in the weld vicinity in the constructed temperature field model, the thermal stress field model, and the mechanical load stress model, so that multiple assessment paths can be depicted, and the subsequent extraction of stress intensity factors is facilitated through the assessment paths.

[0094] According to the operation collection data, temperature field analysis, thermal stress analysis and mechanical load analysis are performed on each of the evaluation paths to obtain a transient temperature field curve, a transient thermal stress curve and a transient mechanical load stress curve corresponding to each of the evaluation paths;

[0095] It can be understood that the process of temperature field analysis is to filter out the transient temperature field data of each node in each of the evaluation paths from the temperature field cloud map in the operation collection data, so as to obtain the transient temperature field data of each of the evaluation paths, and analyze the transient temperature field data of each of the evaluation paths, analyze the temperature distribution when the transient temperature changes drastically, and draw the transient temperature field curve corresponding to each of the evaluation paths, and the transient temperature field curve reflects the temperature change curve of each node over time; the process of thermal stress analysis is to filter out the transient thermal stress field data of each node in each of the evaluation paths from the thermal stress field cloud map in the operation collection data, so as to obtain the transient thermal stress field data of each of the evaluation paths, and analyze the transient thermal stress field data of each of the evaluation paths, and analyze the transient thermal stress field data of each of the evaluation paths. The thermal stress distribution when the transient temperature changes drastically, and the process of depicting the transient thermal stress field curve corresponding to each of the evaluation paths, wherein the transient thermal stress field curve reflects the thermal stress change curve of each node over time; the process of the mechanical load analysis is to screen out the transient mechanical load stress field data of each node in each of the evaluation paths from the mechanical load stress field cloud map in the operation acquisition data, thereby obtaining the transient mechanical load stress field data of each of the evaluation paths, and analyzing the transient mechanical load stress field data of each of the evaluation paths, analyzing the mechanical load stress distribution when the transient temperature changes drastically, and depicting the transient mechanical load stress field curve corresponding to each of the evaluation paths, wherein the transient mechanical load stress field curve reflects the mechanical load stress change curve of each node over time.

[0096] Summarizing all the transient temperature field curves to obtain the transient temperature field distribution, and summarizing all the transient thermal stress curves to obtain the transient thermal stress distribution, and summarizing all the transient mechanical load stress curves to obtain the transient mechanical load stress distribution;

[0097] It can be understood that all the transient temperature field curves are summarized in a three-dimensional coordinate of space, time and temperature to obtain the transient thermal stress distribution; all the transient thermal stress curves are summarized in a three-dimensional coordinate of space, time and thermal stress to obtain the transient thermal stress distribution; all the transient mechanical load stress curves are summarized in a three-dimensional coordinate of space, time and mechanical load stress to obtain the transient mechanical load stress distribution.

[0098] The transient temperature field distribution, the transient thermal stress distribution and the transient mechanical load stress distribution are determined as the stress results.

[0099] The present invention realizes automatic division of temperature field models, thermal stress field models and mechanical load stress models through multi-dimensional structural unit division, and automatically, scientifically and quickly identifies the evaluation path, and uses temperature field analysis, thermal stress analysis and mechanical load analysis to obtain stress results in temperature dimension, thermal stress dimension and mechanical load stress dimension, thereby reducing the cost of manually searching for evaluation paths and analyzing and outputting stress results, improving efficiency, and improving the accuracy and quality of stress result output.

[0100] In one embodiment, the stress intensity factor analysis method is used to perform fatigue crack growth and stress corrosion crack growth on the stress result to obtain a crack evaluation result, including:

[0101] Obtaining a BOSS pipeline radius value and a BOSS pipeline wall thickness value in the pipeline operation data;

[0102] Identify the circumferential crack region and the axial crack region according to the BOSS pipe radius value, the BOSS pipe wall thickness value and the BOSS pipe material parameters in the material parameters;

[0103] It can be understood that the process of identifying the annular crack area is a process of detecting the optimal distance between each node on the outer surface of the annular crack area and all the evaluation paths in the BOSS head area model based on the annular crack parameters; the process of identifying the axial crack area is a process of detecting the largest intersection between the axial crack area and all the evaluation paths in the BOSS head area model based on the semi-elliptical crack parameters.

[0104] Using a stress intensity factor analysis method, polynomial fitting is performed on the transient temperature field distribution, the transient thermal stress distribution, and the transient mechanical load stress distribution, and the circumferential crack stress intensity factor and the axial crack stress intensity factor are calculated through a stress intensity factor function;

[0105] It can be understood that the stress intensity factor analysis method is to perform polynomial fitting on the stress perpendicular to the crack surface on the BOSS pipe wall thickness at the location of the crack, and then use the stress intensity factor function to calculate the stress intensity factor of the crack. The process of polynomial fitting of the transient temperature field distribution, the transient thermal stress distribution and the transient mechanical load stress distribution is to combine the transient temperature field distribution with the annular crack area and the axial crack area, and the temperature stress results of the annular crack area and the axial crack area can be output respectively through the ANSYS simulation tool software. According to the transient thermal stress field distribution combined with the annular The circumferential crack region and the axial crack region can be respectively outputted through the ANSYS simulation tool software for thermal stress results of the circumferential crack region and the axial crack region. According to the transient mechanical load stress distribution, the circumferential crack region and the axial crack region can be respectively outputted through the ANSYS simulation tool software for mechanical load stress results of the circumferential crack region and the axial crack region. The circumferential crack stress intensity factor is obtained by adopting a stress intensity factor function, multiplying the temperature stress results, thermal stress results and mechanical load stress results of the circumferential crack region by their respective weighted factors, and then rounding and summing them. The axial crack stress intensity factor is obtained by multiplying the temperature stress result, thermal stress result and mechanical load stress result of the axial crack region by their respective weighted factors using the stress intensity factor function, rounding the sum and summing them up. After multiplication, we get: where a2 is the crack depth of the axial crack.

[0106] According to the BOSS pipe material parameters, the circumferential crack stress intensity factor and the axial crack stress intensity factor, fatigue crack growth and stress corrosion crack growth are performed on the circumferential crack region and the axial crack region respectively to obtain crack evaluation results.

[0107] It can be understood that the fatigue crack extension is an extension method for estimating the crack fatigue life according to the fatigue crack extension rate, the fatigue extension rate refers to the increase in crack length per cycle of alternating stress, and the fatigue extension rate is related to the material parameters and stress intensity factor of the BOSS tube. The stress corrosion crack extension is an extension method for estimating the crack corrosion life according to the stress corrosion extension rate, and the stress corrosion extension rate refers to the increment of crack extension per cycle under stress corrosion conditions jointly generated by stress, environment and material. The stress corrosion crack extension rate is related to the material parameters and stress intensity factor of the BOSS tube. Fatigue crack extension and stress corrosion crack extension are performed on the circumferential crack area to obtain a circumferential crack evaluation result, and fatigue crack extension and stress corrosion crack extension are performed on the axial crack area to obtain an axial crack evaluation result, and the circumferential crack evaluation result and the axial crack evaluation result are determined as the crack evaluation result.

[0108] Among them, the circumferential crack evaluation result shows the crack extension result at the end of each year during the life cycle of the nuclear power plant base station when the nuclear power plant BOSS head has circumferential cracks, and the axial crack evaluation result shows the crack extension result at the end of each year during the life cycle of the nuclear power plant base station when the nuclear power plant BOSS head has semi-elliptical cracks.

[0109] The present invention realizes automatic identification of circumferential crack areas and axial crack areas, uses stress intensity factor analysis method, and calculates the circumferential crack stress intensity factor and the axial crack stress intensity factor respectively through the stress intensity factor function, thereby outputting crack evaluation results, and can scientifically, objectively and quickly output the crack evaluation results of the annual crack expansion of circumferential cracks and semi-elliptical cracks. The method for evaluating the results of crack expansion from the circumferential and axial dimensions for the structure of the BOSS head weld defect of the nuclear power plant can better provide technical support and guarantee for the safe operation of the nuclear power plant, reduce the huge losses caused by not taking timely measures, and improve the operating economic benefits of the nuclear power plant.

[0110] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as follows: Figure 4 As shown. The computer device includes a processor, a memory, a network interface and a database connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, computer-readable instructions and a database. The internal memory provides an environment for the operation of the operating system and computer-readable instructions in the non-volatile storage medium. When the computer-readable instructions are executed by the processor, the above-mentioned nuclear power plant BOSS head weld detection method is implemented.

[0111] In one embodiment, a computer-readable storage medium is provided, on which computer-readable instructions are stored. When the computer-readable instructions are executed by a processor, the above-mentioned nuclear power plant BOSS head weld detection method is implemented.

[0112] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through computer-readable instructions, and the computer-readable instructions can be stored in a non-volatile computer-readable storage medium. When the computer-readable instructions are executed, they can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided by the present invention can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), memory bus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0113] Those skilled in the art will clearly understand that for the sake of convenience and brevity of description, only the division of the above-mentioned functional units or modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional units or modules as needed, that is, the internal structure of the system can be divided into different functional units or modules to complete all or part of the functions described above.

[0114] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A method for detecting weld seams of BOSS head in nuclear power plant, characterized in that: include: After receiving the nuclear power plant BOSS head detection instruction, the radiographic detection result of the nuclear power plant BOSS head is obtained, wherein the radiographic detection result is obtained by performing radiographic flaw detection and nondestructive testing on a preset weld area at the 0 degree position and the 180 degree position of the nuclear power plant BOSS head respectively; the nuclear power plant BOSS head comprises a main pipe and a branch pipe connected to the main pipe at a preset angle, and the preset weld area is connected between the main pipe and the branch pipe; When the X-ray detection result shows that there is a preset weld defect, a phased array ultrasonic nondestructive test is performed on the BOSS head of the nuclear power plant to obtain weld defect information; Acquire the pipeline operation data corresponding to the preset weld area, and determine the weld mechanics evaluation result of the BOSS head of the nuclear power plant according to the pipeline operation data and the weld defect information; When the weld mechanics evaluation result is unqualified in performance, determining the surfacing repair parameters according to the weld mechanics evaluation result; A preset surfacing operation is performed on the nuclear power plant BOSS head according to the surfacing repair parameters.

2. The method for detecting weld seams of BOSS head in nuclear power plant according to claim 1, characterized in that: After obtaining the radiographic detection result of the BOSS head of the nuclear power plant, the method further includes: When the X-ray detection result shows that there is no preset weld defect, normal detection information is sent to a preset recipient, and the normal detection information is used to indicate that there is currently no preset weld defect in the weld area of ​​the BOSS head of the nuclear power plant.

3. The method for detecting weld seams of BOSS head of nuclear power plant as claimed in claim 1, characterized in that: The preset weld area includes a root weld connecting the mother pipe, a top weld connecting the branch pipe, and a main body weld connecting the root weld and the top weld; The phased array ultrasonic nondestructive testing is performed on the BOSS head of the nuclear power plant to obtain weld defect information, including: Controlling the phased array probe to scan the main body weld from the mother pipe side to obtain a first detection waveform of the main body weld; Controlling the phased array probe to scan a root weld of a preset weld area from a first position point on the branch pipe side to obtain a second detection waveform of the root weld area; Controlling the phased array probe to scan the top weld of the preset weld area from the second position point on the branch pipe side to obtain a third detection waveform of the top weld; the distance between the second position point and the main pipe is greater than the distance between the first position point and the main pipe; Obtaining a preset comparison waveform, and comparing the preset comparison waveform with the first detection waveform, the second detection waveform, and the third detection waveform, respectively, to determine a first defect value of the main weld, a second defect value of the root weld area, and a third defect value of the top weld; The weld defect information of the BOSS head of the nuclear power plant is determined according to the first defect value, the second defect value, and the third defect value.

4. The method for detecting weld seams of BOSS head in nuclear power plant as claimed in claim 3, characterized in that: The controlling phased array probe to scan the main body weld from the mother pipe side to obtain a first detection waveform of the main body weld includes: Control the phased array probe to scan the main body weld from the mother pipe side at the 0 degree position, 90 degree position, 180 degree position and 270 degree position of the BOSS head of the nuclear power plant, respectively, to obtain four main body waveforms corresponding to four directions, respectively, and determine the first detection waveform of the main body weld according to the four main body waveforms; The controlling the phased array probe to scan the root weld of a preset weld area from the first position point on the branch pipe side to obtain a second detection waveform of the root weld area includes: Control the phased array probe to scan the root weld from the first position point on the branch pipe side at the 0 degree position, 90 degree position, 180 degree position and 270 degree position of the BOSS head of the nuclear power plant, respectively, to obtain four root waveforms corresponding to four directions, respectively, and determine the second detection waveform of the root weld according to the four root waveforms; The controlling the phased array probe to scan the top weld of the preset weld area from the second position point on the branch pipe side to obtain a third detection waveform of the top weld includes: The phased array probe is controlled to scan the top weld from the second position point on the branch pipe side at the 0 degree position, 90 degree position, 180 degree position and 270 degree position of the BOSS head of the nuclear power plant, respectively, to obtain four top waveforms corresponding to four directions, and the third detection waveform of the top weld is determined according to the four top waveforms.

5. The method for detecting weld seams of BOSS head in nuclear power plant as claimed in claim 3, characterized in that: The preset contrast waveform includes a first contrast waveform; the first defect value includes a first depth value, the second defect value includes a second depth value, and the third defect value includes a third depth value; Before obtaining the preset comparison waveform, the method includes: Controlling the phased array probe to scan a preset square comparison test block to obtain a first pair of preset comparison waveforms; wherein the preset square comparison test block is provided with a plurality of first comparison defect holes distributed in a stepwise manner; and the first pair of preset comparison waveforms characterizes the depth of the first comparison defect holes in the preset square comparison test block; The step of comparing the preset comparison waveform with the first detection waveform, the second detection waveform, and the third detection waveform respectively to determine a first defect value of the main weld, a second defect value of the root weld area, and a third defect value of the top weld includes: Comparing the first comparison waveform with the first detection waveform to determine the first depth value; Comparing the first comparison waveform with the second detection waveform to determine the second depth value; The first comparison waveform is compared with the third detection waveform to determine the third depth value.

6. The method for detecting weld seams of BOSS head in nuclear power plant as claimed in claim 5, characterized in that: The preset contrast waveform includes a second contrast waveform; the first defect value includes a first shape value; the second defect value includes a second shape value; the third defect value includes a third shape value; Before obtaining the preset comparison waveform, the method includes: Controlling the phased array probe to scan a preset pipeline comparison test block to obtain a second comparison waveform; wherein the preset pipeline comparison test block is consistent with the material and size of the nuclear power plant BOSS head, and the preset pipeline comparison test block includes a comparison mother pipe and a comparison branch pipe, and the comparison branch pipe is welded to the comparison mother pipe through a comparison weld area; and a plurality of comparison defect hole groups are provided in the comparison weld area; The step of comparing the preset comparison waveform with the first detection waveform, the second detection waveform, and the third detection waveform respectively to determine a first defect value of the main weld, a second defect value of the root weld area, and a third defect value of the top weld includes: Comparing the first comparison waveform with the first detection waveform to determine the first shape value; Comparing the first comparison waveform with the second detection waveform to determine the second shape value; The first comparison waveform is compared with the third detection waveform to determine the third shape value.

7. The method for detecting weld seams of BOSS head in nuclear power plant according to claim 1, characterized in that: The step of determining the weld mechanics evaluation result of the BOSS head of the nuclear power plant according to the pipeline operation data and the weld defect information includes: Obtaining model constraints of the nuclear power plant BOSS head; Generate a BOSS head area model according to the main pipeline parameters in the pipeline operation data and the weld defect information; According to the model constraints and the material parameters and operation acquisition data in the pipeline operation data, the temperature field analysis, thermal stress analysis and mechanical load analysis are performed on the BOSS head area model to obtain stress results; Using stress intensity factor analysis method, fatigue crack growth and stress corrosion crack growth are performed on the stress results to obtain crack evaluation results; The crack evaluation results are subjected to fracture analysis, and weld mechanics evaluation results corresponding to the BOSS head of the nuclear power plant are output.

8. The method for detecting weld seams of BOSS head in nuclear power plant as claimed in claim 7, characterized in that: According to the model constraints and the material parameters and operation acquisition data in the pipeline operation data, the temperature field analysis, thermal stress analysis and mechanical load analysis are performed on the BOSS head area model to obtain stress results, including: According to the material parameters and the model constraints, the BOSS head region model is divided into multi-dimensional structural units to divide the temperature field model, the thermal stress field model and the mechanical load stress model; Performing assessment path identification on the temperature field model, the thermal stress field model, and the mechanical load stress model to identify a plurality of assessment paths; According to the operation collection data, temperature field analysis, thermal stress analysis and mechanical load analysis are performed on each of the evaluation paths to obtain a transient temperature field curve, a transient thermal stress curve and a transient mechanical load stress curve corresponding to each of the evaluation paths; Summarizing all the transient temperature field curves to obtain the transient temperature field distribution, and summarizing all the transient thermal stress curves to obtain the transient thermal stress distribution, and summarizing all the transient mechanical load stress curves to obtain the transient mechanical load stress distribution; The transient temperature field distribution, the transient thermal stress distribution and the transient mechanical load stress distribution are determined as the stress results.

9. The method for detecting weld seams of BOSS head in nuclear power plant as claimed in claim 8, characterized in that: The stress intensity factor analysis method is used to perform fatigue crack growth and stress corrosion crack growth on the stress result to obtain a crack evaluation result, including: Obtaining a BOSS pipeline radius value and a BOSS pipeline wall thickness value in the pipeline operation data; Identify the circumferential crack region and the axial crack region according to the BOSS pipe radius value, the BOSS pipe wall thickness value and the BOSS pipe material parameters in the material parameters; Using a stress intensity factor analysis method, polynomial fitting is performed on the transient temperature field distribution, the transient thermal stress distribution, and the transient mechanical load stress distribution, and the circumferential crack stress intensity factor and the axial crack stress intensity factor are calculated through a stress intensity factor function; According to the BOSS pipe material parameters, the circumferential crack stress intensity factor and the axial crack stress intensity factor, fatigue crack growth and stress corrosion crack growth are performed on the circumferential crack region and the axial crack region respectively to obtain crack evaluation results.

10. The method for detecting weld seams of BOSS head in nuclear power plant according to claim 1, characterized in that: After determining the weld mechanics evaluation result of the BOSS head of the nuclear power plant according to the pipeline operation data and the weld defect information, the method further includes: When the weld mechanics evaluation result shows that the performance is qualified, an in-service monitoring plan is determined according to the weld mechanics evaluation result, and an in-service monitoring operation is performed on the nuclear power plant BOSS head according to the in-service monitoring plan.

11. The method for detecting weld seams of BOSS head in nuclear power plant according to claim 1, characterized in that: After performing a preset surfacing operation on the nuclear power plant BOSS head according to the surfacing repair parameters, the method further includes: Performing phased array ultrasonic nondestructive testing on the nuclear power plant BOSS head again to obtain surfacing repair defect information corresponding to the surfacing layer after the nuclear power plant BOSS head performs the preset surfacing operation; When the preset weld defect is not included in the surfacing repair defect information, it is confirmed that the surfacing repair of the preset weld area is qualified.

12. A computer device comprising a memory, a processor, and computer-readable instructions stored in the memory and executable on the processor, characterized in that: When the processor executes the computer-readable instructions, the nuclear power plant BOSS head weld detection method as described in any one of claims 1 to 11 is implemented.

13. A computer-readable storage medium storing computer-readable instructions, characterized in that: When the computer-readable instructions are executed by a processor, a nuclear power plant BOSS head weld detection method as described in any one of claims 1 to 11 is implemented.

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