Inspection and flaw detection method and system for long-distance oil and gas pipeline

Abstract

The invention discloses an inspection and flaw detection method and system for a long-distance oil and gas pipeline, and relates to the field of inspection and flaw detection of oil and gas pipelines, the inspection and flaw detection system comprises a data acquisition module, an auxiliary module, a pipeline module, an environment identification module and an early warning module, and comprises the following steps: judging and analyzing valve bubble movement and compensator stress of the pipeline; analyzing cracks, temperature distribution, slag inclusion and air holes of the oil and gas pipeline to obtain a crack complex shape of the oil and gas pipeline, a temperature release difference value of the oil and gas pipeline and a crack clamping hole value of the oil and gas pipeline, and further analyzing to obtain a pipeline defect value of the oil and gas pipeline; the states of soil, identification piles, warning tapes and warning boards of the oil and gas pipelines are analyzed to obtain outer ring identification values of the oil and gas pipelines, the use states of the oil and gas pipelines are analyzed, corresponding early warning signals are sent out, the stability and reliability of energy supply can be guaranteed, and the probability of leakage accidents is reduced.

Description

Technical Field

[0001] The present invention relates to the field of inspection and flaw detection of oil and gas pipelines, and specifically to a method and system for inspecting and flaw detecting long-distance oil and gas pipelines. Background Art

[0002] With the continuous consumption of social energy, the issue of energy has attracted increasing attention. At the same time, as an important way for the country to transport energy, the safe and stable operation of oil and gas pipelines is directly related to the safety of surrounding residents and the environment, as well as the stability and reliability of the entire energy supply. Once accidents such as leakage occur, huge losses and impacts will be caused. The traditional inspection and flaw detection of oil and gas pipelines rely on the experience and observation of personnel, resulting in low efficiency and inability to ensure the accuracy of inspection and flaw detection. Therefore, the method and system for inspecting and flaw detecting long-distance oil and gas pipelines have emerged.

[0003] When the existing methods for inspecting and flaw detecting long-distance oil and gas pipelines are in operation, they cannot consider the operating status of pipeline accessories, nor can they accurately identify the operating status of the pipeline and the environmental markings of the pipeline. Moreover, they cannot timely determine the operating status of long-distance oil and gas pipelines and issue corresponding warning signals, resulting in the inability to ensure the stability and reliability of energy supply and increasing the probability of leakage accidents.

[0004] To solve the above defects, a technical solution is provided now. Summary of the Invention

[0005] To solve the technical problems raised in the above background art, the present invention is proposed. Embodiments of the present invention provide a method and system for inspecting and flaw detecting long-distance oil and gas pipelines.

[0006] The object of the present invention can be achieved by the following technical solutions: A method for inspecting and flaw detecting long-distance oil and gas pipelines includes the following steps:

[0007] S1: Analyze and determine the movement of valve bubbles and compensator stress of the pipeline to obtain the accessory melting deviation value of the oil and gas pipeline;

[0008] S2: Analyze cracks, temperature distribution, slag inclusions, and pores in the oil and gas pipeline to obtain the pipeline defect value of the oil and gas pipeline;

[0009] S3: Analyze the soil, identification piles, warning tapes, and warning signs of the oil and gas pipeline to obtain the outer ring identification value of the oil and gas pipeline;

[0010] S4: Analyze the usage status of the oil and gas pipeline and issue corresponding warning signals.

[0011] Further, the steps for analyzing the pipeline defect value of the oil and gas pipeline are as follows:

[0012] By using a pipe inspection robot in an oil and gas pipeline, an ultrasonic phased array probe is carried to travel inside the pipeline. The probe is coupled with the inner wall of the pipeline through the medium inside the pipeline to obtain an ultrasonic phased array imaging diagram. The ultrasonic phased array imaging diagram is divided into several regions to determine the defect status of each region. If the sum value of the peak factor, echo amplitude, and propagation delay time of the echo signal in the A-scan waveform in the imaging diagram of the region is greater than the set threshold and there are linear features in the B-scan and C-scan imaging diagrams, it is determined that there is a crack in the region. The peak factor is the ratio of the peak value to the effective value of the echo signal. If the standard deviation of the echo signal amplitude, the half-height width of the wave peak, and the echo propagation time in the A-scan waveform in the imaging diagram of the region is lower than the set threshold and there is an approximately circular dark area in the B-scan and C-scan imaging diagrams, it is determined that there are pores in the region. The approximately circular dark area means that the region in the image satisfies both the gray value being less than the set threshold and the contour roundness value of the region being in the range of 0.9 - 1.1. If the peak-to-valley value of the echo signal and the standard deviation of the echo amplitude in the A-scan waveform in the imaging diagram of the region are greater than the set threshold and there are irregularly shaped dark areas in the B-scan and C-scan imaging diagrams, it is determined that there is slag inclusion in the region. The irregularly shaped dark area means that it satisfies both the gray value being less than the set threshold and the perimeter-to-area ratio of the region being greater than 2. Obtain the type numbers of cracks, slag inclusions, and pores existing in each region, which are 0, 1, 2, and 3 respectively, and correspond to the values 0, t1, t2, and t3 respectively, where t3 > t2 > t1. Statistically sum up the numerical values of all region types in the ultrasonic phased array imaging diagram of the oil and gas pipeline, and mark it as the crack, slag inclusion, and pore value of the oil and gas pipeline;

[0013] Normalize the crack restoration state of the oil and gas pipeline, the abnormal temperature difference value of the oil and gas pipeline leakage, and the crack, slag inclusion, and pore value of the oil and gas pipeline. Take the crack restoration state of the oil and gas pipeline as the length of the upper top side of the trapezoid, the abnormal temperature difference value of the oil and gas pipeline leakage as the length of the lower bottom side of the trapezoid, and the crack, slag inclusion, and pore value of the oil and gas pipeline as the height of the trapezoid to establish a trapezoid. Identify the area of the trapezoid and mark it as the pipeline defect value GQX of the oil and gas pipeline.

[0014] Furthermore, the analysis steps for the crack restoration state of the oil and gas pipeline and the abnormal temperature difference value of the oil and gas pipeline leakage are as follows:

[0015] Couple the probe directly with the ground on the oil and gas pipeline through a couplant, and transmit ultrasonic signals into the oil and gas pipeline through an electromagnetic ultrasonic flaw detection device to obtain the received signal information of the ultrasonic flaw detector. Obtain the standard deviation of the echo amplitude, the spectral bandwidth of the echo signal, the energy attenuation rate of the echo signal, and the fractal dimension of the echo signal, and sum them to obtain the crack complex value of the oil and gas pipeline. The fractal dimension of the echo signal is calculated by the box dimension method, and the energy attenuation rate of the echo signal is the ratio of the energy of the transmitted ultrasonic wave to the energy of the received echo signal. Detect the oil and gas pipeline with an infrared thermal imager, divide the oil and gas pipeline into several regions, obtain the temperature value of each region. If the temperature value of the region is greater than the set threshold TT1, then correspond this region to the material leakage region. If the temperature value of the region is less than the set threshold TT2, then correspond this region to the abnormal insulation layer region. Statistically analyze the proportion of the material leakage region and the abnormal insulation layer region, and label it as the temperature and leakage anomaly value of the oil and gas pipeline.

[0016] Further, the analysis steps of the affiliated fusion deviation value of the oil and gas pipeline are as follows:

[0017] Perform photoelastic coating treatment on the compensator of the oil and gas pipeline, divide the compensator into several regions. First, make light incident along the direction perpendicular to the external force compensator of each region through a polarized light field, and sum up the change value of the optical path difference and the change value of the fringe characteristic value to obtain the optical difference fringe characteristic change value. The change value of the fringe characteristic value is the change value of the position, shape, contrast, and distance between adjacent dark fringes of the fringe within a certain period of time. When the light intensity value of the fringe is lower than the set light intensity threshold, it corresponds to a dark fringe. Continuously change the direction of the polarized light field. When the optical difference fringe characteristic change value corresponding to the polarized light field is less than the set threshold, the fringe formed by this polarized light field is an isoclinic fringe, and obtain the rotation angle zθ of the polarized light field at this time c And the included angle xθ between the isoclinic fringe and the x-axis c , where c represents the serial number of the region, and according to the formula Obtain the principal stress direction β of each region c , make light incident along the direction perpendicular to the external force compensator of each region through the polarized light field, and obtain the order number Js of the isochromatic fringes c 、The wall thickness b of each region of the oil and gas pipeline compensator c , the fringe value tw of the coating material c , according to the formula Δσ 0c =Js c ×tw c / b c , obtain the orthotropic principal stress difference Δσ of each region 0c , rotate the angles θ of the polarizer and analyzer in the polarized light field c , obtain the order number Jx of the isochromatic fringes after rotating the polarized light field c 、According to the formula Δσ c =Jxc ×tw c / (b c ×cosθ c ) to obtain the inclined principal stress difference Δσ of each region c , and establish a system of equations Solve the equations to obtain the principal stresses σ1 of each region c and σ2 c , where According to the formula Obtain the equivalent stress σe of each region c , count the value range of the principal stress direction of each region and the standard deviation of the equivalent stress of each region, perform weighted calculation, multiply by the corresponding weight factor coefficient to obtain the differential deviation value that the compensator of the oil and gas pipeline should deflect;

[0018] Mark the differential deviation value that the compensator of the oil and gas pipeline should deflect as bcz, perform normalization processing with the valve gas melting value Qrz, substitute it into the set formula YRP = p1×bcz + p2×Qrz, and perform calculation to obtain the accessory melting deviation value YRP of the oil and gas pipeline, where p1 and p2 are the preset proportional factor coefficients of the differential deviation value that the compensator of the oil and gas pipeline should deflect and the valve gas melting value respectively.

[0019] Furthermore, the analysis steps of the valve gas melting value are as follows:

[0020] Step 3: Use the edge detection algorithm to detect the edges of the bubbles in each bubble motion window, extract the contours of the bubbles, obtain the distances from each pixel point of the bubble contour in the bubble motion window of two adjacent frames to its centroid coordinates, and perform difference calculation and take the absolute value, which is marked as the centroid deviation value of the bubble contour of two adjacent frames of images. Calculate the Hu moment eigenvalue of the bubble motion window in two adjacent frames of images by the Hu moment method and According to the formula Obtain the moment difference value lz of the bubble contour of two adjacent frames of images, λ is the set correction factor coefficient, i is the serial number of the Hu moment eigenvalue, taking positive integers, the maximum value is 7. Sum the centroid deviation value of the bubble contour of two adjacent frames of images and the moment difference value of the bubble contour of two adjacent frames of images to obtain the bubble cracking and melting value of two adjacent frames of images. Count the integral value of the bubble cracking value in the continuous image sequence within a certain time of each bubble motion window to obtain the bubble cracking and melting value of each bubble motion window, and sum it with the bubble track vector value of each bubble motion window to obtain the bubble motion and melting value of each bubble motion window;

[0021] Step 4: Calculate the average value of the bubble movement and fusion values of each bubble movement window, marked as the average bubble movement and fusion value of the bubble movement window, marked as qpj. Calculate the standard value of the bubble movement and fusion values of each bubble movement window, marked as the bubble movement and fusion fluctuation value of the bubble movement window, marked as qbj. Calculate the ratio of the bubble movement window to all windows, marked as the bubble rate qpl, and substitute it into the set formula model to calculate the valve gas fusion movement value Qrz, where a1, a2, a3, a4, a5, and a6 are all preset weight factor coefficients, and a1 > a4, a2 > a5, a3 > a6.

[0022] Furthermore, the analysis steps for the bubble track vector values of each bubble movement window are as follows:

[0023] Step 1: Use an industrial camera to capture the valve of the pipeline, obtain a continuous image sequence of the valve within a certain period of time. Use a filtering algorithm to denoise the image, convert the denoised color image into a grayscale image, divide the grayscale image into several windows, and calculate the optical flow vectors of the pixels in each window. The optical flow vector is the movement direction and speed of the pixel in the image sequence. When the optical flow amplitude of the window is greater than the set threshold, the corresponding window is the bubble movement window;

[0024] Step 2: Obtain the components of the optical flow vector of the j-th pixel in the x-axis and y-axis directions in the bubble movement window, marked as fl j x and fl j y , where j = 1, 2,..., J, and J is the maximum value of the pixel sequence number. According to the formula obtain the centroid coordinates (xz, yz) of each bubble movement window, where (x j , y j ) is the coordinate of the j-th pixel in the bubble movement window. By tracking the centroid coordinates of the bubble movement window in the time image sequence, obtain the bubble movement trajectory of each bubble movement window, obtain the change in the optical flow vector of the bubble by obtaining the change in the optical flow vector of the bubble movement window in the time image sequence, perform a weighted calculation on the bubble movement trajectory range and the change in the optical flow vector of the bubble of each bubble movement window, and multiply by the corresponding weight factor coefficient to obtain the bubble track vector value of each bubble movement window.

[0025] Furthermore, the analysis steps for issuing the corresponding warning signal are as follows:

[0026] If the comprehensive inspection value of the oil and gas pipeline is within the inspection gradient reference interval TC1, a signal of extremely serious damage to the oil and gas pipeline is sent, and Measure 1 is executed. If the comprehensive inspection value of the oil and gas pipeline is within the inspection gradient reference interval TC2, a signal of relatively serious damage to the oil and gas pipeline is sent, and Measure 2 is executed. If the comprehensive inspection value of the oil and gas pipeline is within the inspection gradient reference interval TC3, a signal of general damage to the oil and gas pipeline is sent, and Measure 3 is executed. If the comprehensive inspection value of the oil and gas pipeline is within the inspection gradient reference interval TC4, a signal of good damage to the oil and gas pipeline is sent.

[0027] Furthermore, the steps for analyzing the comprehensive inspection value of the oil and gas pipeline are as follows:

[0028] The affiliated melting deviation value YRP of the oil and gas pipeline, the pipeline defect value GQX of the oil and gas pipeline, and the outer ring identification value WHB of the oil and gas pipeline are normalized and substituted into the set formula YZZ = τ×(tq1×YRP + tq2×GQX) / (tq3×WHB) model for calculation to obtain the comprehensive inspection value YZZ of the oil and gas pipeline. tq1, tq2, and tq3 are all preset weight factor coefficients, and τ is the set correction factor coefficient.

[0029] Furthermore, the steps for analyzing the outer ring identification value of the oil and gas pipeline are as follows:

[0030] Obtain the soil corrosion value, identification pile information loss value, and warning value of the oil and gas pipeline, which are respectively marked as tf, ylz, and qsl, and calculate according to the formula to obtain the outer ring identification value WHB of the oil and gas pipeline. g1, g2, and g3 are all set influence factor coefficients.

[0031] According to the present application. On the other hand, a long-distance oil and gas pipeline inspection and flaw detection system is provided, including:

[0032] The data acquisition module is used to collect affiliated information, pipeline information, and environmental identification information, and send them to the affiliated module, pipeline module, and environmental identification module respectively;

[0033] The affiliated module is used to receive the affiliated information to judge and analyze the valve bubble movement and compensator stress of the pipeline to obtain the affiliated melting deviation value of the oil and gas pipeline;

[0034] The pipeline module is used to receive the pipeline information and analyze the cracks, temperature distribution, slag inclusions, and pores of the oil and gas pipeline to obtain the pipeline defect value of the oil and gas pipeline;

[0035] The environmental identification module is used to receive the environmental identification information and analyze the soil, identification piles, warning tapes, and warning signs of the oil and gas pipeline to obtain the outer ring identification value of the oil and gas pipeline;

[0036] The warning module is used to receive the affiliated fusion deviation value of the oil and gas pipeline, the pipeline defect value of the oil and gas pipeline, and the outer ring identification value of the oil and gas pipeline, analyze the usage status of the oil and gas pipeline, and issue corresponding warning signals.

[0037] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0038] 1. By judging and analyzing the valve bubble movement and compensator stress of the pipeline, the present invention obtains the compensator differential deviation value and valve gas fusion value of the oil and gas pipeline, further analyzes to obtain the affiliated fusion deviation value of the oil and gas pipeline, analyzes the crack, temperature distribution, slag inclusion, and pores of the oil and gas pipeline to obtain the crack recovery state, temperature leakage abnormal value, and crack inclusion hole value of the oil and gas pipeline, and further analyzes to obtain the pipeline defect value of the oil and gas pipeline, analyzes the soil, identification pile, warning tape, and warning sign status of the oil and gas pipeline to obtain the outer ring identification value of the oil and gas pipeline, which can consider the operation status of pipeline accessory structures and accurately identify the operation status of the pipeline and the environmental identification of the pipeline.

[0039] 2. By analyzing the usage status of the oil and gas pipeline and issuing corresponding warning signals, the present invention can timely judge the operation status of the long-distance oil and gas pipeline and issue corresponding warning signals, which can ensure the stability and reliability of energy supply and reduce the probability of leakage accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. The following drawings are not deliberately drawn to scale in actual size, and the focus is on showing the gist of the present invention.

[0041] Figure 1 It is a schematic flow chart of the method of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0042] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings. Obviously, the described embodiments are only partial embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts also belong to the scope of protection of the present invention.

[0043] As Figure 1 shown, a long-distance oil and gas pipeline inspection and flaw detection system includes a data acquisition module, an affiliated module, a pipeline module, an environmental identification module, and a warning module.

[0044] The data acquisition module is used to collect affiliated information, pipeline information, and environmental identification information, and send them to the affiliated module, pipeline module, and environmental identification module respectively;

[0045] The accessory module is used to receive accessory information to judge and analyze the valve bubble movement and compensator stress of the pipeline, so as to obtain the accessory stress deviation value of the oil and gas pipeline. The specific analysis is as follows:

[0046] Step 1: Use an industrial camera to capture the valve of the pipeline, obtain a continuous image sequence of the valve within a certain period of time, use a filtering algorithm to denoise the image, convert the denoised color image into a grayscale image, divide the grayscale image into several windows, and calculate the optical flow vectors of the pixels in each window. The optical flow vector is the movement direction and speed of the pixel in the image sequence. When the optical flow amplitude of the window is greater than the set threshold, the corresponding window is the bubble movement window;

[0047] Step 2: Obtain the components of the optical flow vector of the j-th pixel in the x-axis and y-axis directions in the bubble movement window, and mark them as fl j x and fl j y , where j = 1, 2,..., J, and J is the maximum value of the pixel sequence number. According to the formula obtain the centroid coordinates (xz, yz) of each bubble movement window, where (x j , y j ) is the coordinate of the j-th pixel in the bubble movement window. By tracking the centroid coordinates of the bubble movement window in the time image sequence, obtain the bubble movement trajectory of each bubble movement window, obtain the change in the optical flow vector of the bubble movement window in the time image sequence, obtain the optical flow vector change value of the bubble, and perform a weighted calculation on the bubble movement trajectory range of each bubble movement window and the optical flow vector change value of the bubble, and multiply by the corresponding weight factor coefficient to obtain the bubble track vector value of each bubble movement window;

[0048] Step 3: Use an edge detection algorithm to detect the edges of the bubbles in each bubble movement window, extract the contours of the bubbles, obtain the distances from each pixel point of the bubble contour in the bubble movement window of two adjacent frames of images to its centroid coordinates, and perform a difference calculation and take the absolute value, which is marked as the bubble contour centroid deviation value of two adjacent frames of images. Calculate the Hu moment eigenvalue of the bubble movement window in two adjacent frames of images through the Hu moment method and According to the formula obtain the bubble moment difference value lz of two adjacent frames of images, where λ is the set correction factor coefficient, i is the Hu moment eigenvalue number, taking positive integers, and the maximum value is 7. Sum the bubble contour centroid deviation values of two adjacent frames of images and the bubble moment difference values of two adjacent frames of images to obtain the bubble splitting and melting value of two adjacent frames of images. Statistically calculate the integral value of the bubble splitting value in the continuous image sequence of each bubble movement window within a certain period of time to obtain the bubble splitting and melting value of each bubble movement window, and sum it with the bubble track vector value of each bubble movement window to obtain the bubble movement and melting value of each bubble movement window;

[0049] It should be noted that the larger the bubble cracking and fusion value, the more significant the bubble fusion and splitting. The larger the bubble movement and fusion value, the more complex the movement trajectory of the bubble, and the more significant the bubble fusion and splitting;

[0050] Step 4: Statistically calculate the average value of the bubble movement and fusion values in each bubble movement window, marked as the average bubble movement and fusion value of the bubble movement window, denoted as qpj. Statistically calculate the standard value of the bubble movement and fusion values in each bubble movement window, marked as the bubble movement and fusion fluctuation value of the bubble movement window, denoted as qbj. Statistically calculate the ratio of the bubble movement window to all windows, marked as the bubble rate qpl, and substitute it into the set formula model to calculate the valve gas fusion and movement value Qrz, where a1, a2, a3, a4, a5, and a6 are all preset weight factor coefficients, and a1 > a4, a2 > a5, a3 > a6. The magnitudes of a1, a2, a3, a4, a5, and a6 are custom-set by those skilled in the art according to actual use, and are respectively taken as 1.1, 2.1, 2.1, 1.5, 0.9, and 2.1. e is the natural constant, with a value of 2.718;

[0051] Perform photoelastic coating treatment on the compensator of the oil and gas pipeline. Divide the compensator into several regions. First, make light incident along the direction perpendicular to the external force compensator of each region through a polarized light field. Statistically calculate the change value of the optical path difference and the change value of the fringe characteristic value and sum them to obtain the optical difference fringe characteristic change value. The change value of the fringe characteristic value is the change value of the position, shape, contrast, and distance between adjacent dark fringes of the fringe within a certain period of time. When the light intensity value of the fringe is lower than the set light intensity threshold, it corresponds to a dark fringe. Continuously change the direction of the polarized light field. When the optical difference fringe characteristic change value corresponding to the polarized light field is less than the set threshold, the fringe formed by the polarized light field is an isoclinic fringe, and obtain the rotation angle zθ of the polarized light field at this time c and the angle xθ between the isoclinic fringe and the x-axis c , where c represents the serial number of the region. According to the formula obtain the principal stress direction β of each region c . The polarized light field makes light incident along the direction perpendicular to the external force compensator of each region, and obtain the order of the isochromatic fringe Js c , the wall thickness b of each region of the oil and gas pipeline compensator c , the fringe value tw of the coating material c . According to the formula Δσ 0c = Js c ×tw c / b c , obtain the orthotropic principal stress difference Δσ of each region 0c . Rotate the angles θ of the polarizer and analyzer in the polarized light field c , and obtain the order of the isochromatic fringe Jx after rotating the polarized light fieldc , according to the formula Δσ c = Jx c ×tw c / (b c ×cosθ c ), the inclined principal stress difference Δσ of each region is obtained c , and a system of equations is established By solving the equations, the principal stresses σ1 c and σ2 c of each region are obtained, where According to the formula the equivalent stress σe of each region is obtained c . The value ranges of the principal stress directions of each region and the standard deviations of the equivalent stresses of each region are statistically analyzed, weighted calculations are performed, and the weighted calculation results are multiplied by the corresponding weight factor coefficients to obtain the differential deviation value that the compensator of the oil and gas pipeline should deflect;

[0052] The differential deviation value that the compensator of the oil and gas pipeline should deflect is marked as bcz, and it is normalized with the valve gas fusion value Qrz. Substituting it into the set formula YRP = p1×bcz + p2×Qrz for calculation to obtain the accessory fusion deviation value YRP of the oil and gas pipeline, where p1 and p2 are the preset proportional factor coefficients of the differential deviation value that the compensator of the oil and gas pipeline should deflect and the valve gas fusion value respectively, and the values are determined by the personnel in this professional field, specifically 2.1 and 2.3 respectively;

[0053] The pipeline module is used to receive pipeline information and analyze the cracks, temperature distribution, slag inclusions, and pores of the oil and gas pipeline to obtain the pipeline defect value of the oil and gas pipeline. The specific analysis steps are as follows:

[0054] The probe is directly coupled to the ground on the oil and gas pipeline through a coupling agent, and an ultrasonic signal is transmitted into the oil and gas pipeline through an electromagnetic ultrasonic flaw detector to obtain the received signal information of the ultrasonic flaw detector. The standard deviation of the echo amplitude, the spectral bandwidth of the echo signal, the energy attenuation rate of the echo signal, and the fractal dimension of the echo signal are obtained, and the sum is performed to obtain the crack complex value of the oil and gas pipeline. The fractal dimension of the echo signal is calculated by the box dimension method, and the energy attenuation rate of the echo signal is the ratio of the energy of the transmitted ultrasonic wave to the energy of the received echo signal. The larger the crack complex value of the oil and gas pipeline, the more irregular the crack of the oil and gas pipeline; the oil and gas pipeline is detected by an infrared thermal imager, and the oil and gas pipeline is divided into several regions to obtain the temperature values of each region. If the temperature value of a region is greater than the set threshold TT1, then the region is corresponding to a material leakage region. If the temperature value of a region is less than the set threshold TT2, then the region is corresponding to an abnormal insulation layer region. The ratio of the material leakage region and the abnormal insulation layer region is statistically analyzed and marked as the temperature and leakage abnormal value of the oil and gas pipeline;

[0055] By means of a pipeline inspection robot in an oil and gas pipeline, an ultrasonic phased array probe is carried to travel inside the pipeline. The probe is coupled with the inner wall of the pipeline through the medium inside the pipeline to obtain an ultrasonic phased array imaging diagram. The ultrasonic phased array imaging diagram is divided into several regions to determine the defect status of each region. If the sum value of the peak factor, echo amplitude, and propagation delay time of the echo signal in the A-scan waveform in the imaging diagram of the region is greater than the set threshold and there are linear features in the B-scan and C-scan imaging diagrams, it is determined that there is a crack in the region. The peak factor is the ratio of the peak value to the effective value of the echo signal. If the standard deviation of the echo signal amplitude, half-height width of the wave peak, and echo propagation time in the A-scan waveform in the imaging diagram of the region is lower than the set threshold and there is an approximately circular dark area in the B-scan and C-scan imaging diagrams, it is determined that there are pores in the region. The approximately circular dark area means that the region in the image satisfies both the gray value being less than the set threshold and the contour roundness value of the region being within the range of 0.9 - 1.1. If the peak-to-valley value of the echo signal and the standard deviation of the echo amplitude in the A-scan waveform in the imaging diagram of the region are greater than the set threshold and there is an irregularly shaped dark area in the B-scan and C-scan imaging diagrams, it is determined that there is slag inclusion in the region. The irregularly shaped dark area means that it satisfies both the gray value being less than the set threshold and the perimeter-to-area ratio of the region being greater than 2. The perimeter-to-area ratio is the ratio of the perimeter to the area. Obtain the type numbers of cracks, slag inclusions, and pores existing in each region, which are respectively 0, 1, 2, and 3, and correspond to the values 0, t1, t2, and t3 respectively, where t3 > t2 > t1. Statistically calculate the sum value of the numerical values of all region types in the ultrasonic phased array imaging diagram of the oil and gas pipeline, and mark it as the crack, slag inclusion, and pore value of the oil and gas pipeline;

[0056] Normalize the crack restoration of the oil and gas pipeline, the abnormal temperature release value of the oil and gas pipeline, and the crack, slag inclusion, and pore value of the oil and gas pipeline. Take the crack restoration of the oil and gas pipeline as the length of the upper top side of the trapezoid, take the abnormal temperature release value of the oil and gas pipeline as the length of the lower bottom side of the trapezoid, and take the crack, slag inclusion, and pore value of the oil and gas pipeline as the height of the trapezoid to establish a trapezoid. Identify the area of the trapezoid and mark it as the pipeline defect value GQX of the oil and gas pipeline;

[0057] The environmental identification module is used to receive environmental identification information and analyze the status of the soil, identification piles, warning tapes, and warning signs of the oil and gas pipeline to obtain the outer ring identification value of the oil and gas pipeline. The specific analysis is as follows:

[0058] Obtain the soil corrosion value, identification pile information loss value, and warning value of the oil and gas pipeline, which are respectively marked as tf, ylz, and qsl, and calculate according to the formula to obtain the outer ring identification value WHB of the oil and gas pipeline. g1, g2, and g3 are respectively the set influence factor coefficients of the soil corrosion value, identification pile information omission value, and warning omission rate of the oil and gas pipeline, and are respectively taken as 1.1, 2.1, and 3.1. G is the warning value set by the specification;

[0059] It should be noted that the soil corrosion value of the oil and gas pipeline refers to the sum value of the ground deformation degree, the soil color saturation, and the pollutant enrichment concentration; the information loss value of the identification stake refers to the missing values of the pipeline name, pipe diameter, transported medium, and ownership unit information of the identification stake; the warning value refers to the quantity value of the warning tape and warning sign within a certain range.

[0060] The early warning module is used to receive the affiliated melting deviation value of the oil and gas pipeline, the pipeline defect value of the oil and gas pipeline, and the outer ring identification value of the oil and gas pipeline, analyze the usage status of the oil and gas pipeline, and send out corresponding early warning signals. The specific analysis is as follows:

[0061] Normalize the affiliated melting deviation value YRP of the oil and gas pipeline, the pipeline defect value GQX of the oil and gas pipeline, and the outer ring identification value WHB of the oil and gas pipeline, and substitute them into the set formula YZZ = τ×(tq1×YRP + tq2×GQX) / (tq3×WHB) model for calculation to obtain the comprehensive inspection injury value YZZ of the oil and gas pipeline. tq1, tq2, and tq3 are the preset weight factor coefficients of the affiliated melting deviation value of the oil and gas pipeline, the pipeline defect value of the oil and gas pipeline, and the outer ring identification value of the oil and gas pipeline respectively, and τ is the set correction factor coefficient;

[0062] Set the inspection injury gradient reference intervals TC1, TC2, TC3, and TC4 of the oil and gas pipeline, where the inspection injury gradient reference interval TC1 > TC2 > TC3 > TC4; if the comprehensive inspection injury value of the oil and gas pipeline is within the inspection injury gradient reference interval TC1, then send out a signal of extremely serious damage to the oil and gas pipeline, and immediately stop the pipeline operation, set up a warning area, evacuate the surrounding personnel, organize a professional repair team, and quickly formulate a repair plan. If the comprehensive inspection injury value of the oil and gas pipeline is within the inspection injury gradient reference interval TC2, then send out a signal of relatively serious damage to the oil and gas pipeline, and operate the oil and gas pipeline under reduced pressure, conduct a comprehensive non-destructive inspection on the damaged part and its surrounding area, and formulate a detailed repair plan according to the evaluation and inspection results. If the comprehensive inspection injury value of the oil and gas pipeline is within the inspection injury gradient reference interval TC3, then send out a signal of general damage to the oil and gas pipeline, and shorten the inspection and flaw detection cycle of the pipeline. If the comprehensive inspection injury value of the oil and gas pipeline is within the inspection injury gradient reference interval TC4, then send out a signal of good damage to the oil and gas pipeline, and there is no corresponding operation;

[0063] A method for inspecting and flaw detecting long-distance oil and gas pipelines includes the following steps:

[0064] S1: Determine and analyze the valve bubble movement and compensator stress of the pipeline to obtain the affiliated melting deviation value of the oil and gas pipeline;

[0065] S2: Analyze the cracks, temperature distribution, slag inclusions, and pores of the oil and gas pipeline to obtain the pipeline defect value of the oil and gas pipeline;

[0066] S3: Analyze the status of the soil, identification stakes, warning tapes, and warning signs of the oil and gas pipeline to obtain the outer ring identification value of the oil and gas pipeline;

[0067] S4: Analyze the usage status of the oil and gas pipeline and issue corresponding warning signals;

[0068] The above is a description of the present invention and should not be construed as a limitation thereof. Although several exemplary embodiments of the present invention have been described, those skilled in the art will readily understand that many modifications can be made to the exemplary embodiments without departing from the novel teachings and advantages of the present invention. Therefore, all such modifications are intended to be included within the scope of the present invention as defined by the claims. It should be understood that the above is a description of the present invention and should not be considered limited to the specific embodiments disclosed, and modifications to the disclosed embodiments as well as other embodiments are intended to be included within the scope of the appended claims. The present invention is defined by the claims and their equivalents.

Claims

1. A long-distance oil and gas pipeline inspection and flaw detection method, characterized in that: The following steps are involved: S1: Determine and analyze the valve bubble movement and compensator stress of the pipeline to obtain the auxiliary stress deviation value of the oil and gas pipeline; S2: Analyze the cracks, temperature distribution, slag inclusions, and pores of the oil and gas pipeline to obtain the pipeline defect value of the oil and gas pipeline; S3: Analyze the status of the soil, identification piles, warning tapes and warning signs of the oil and gas pipeline to obtain the outer ring identification value of the oil and gas pipeline; S4: Analyze the usage status of oil and gas pipelines and issue corresponding early warning signals.

2. A long-distance oil and gas pipeline inspection and flaw detection method according to claim 1, characterized in that: The pipeline defect value analysis steps of the oil and gas pipeline are as follows: By using an in-pipe inspection robot in an oil and gas pipeline, carrying an ultrasonic phased array probe and moving inside the pipeline, the probe is coupled with the inner wall of the pipeline through the medium inside the pipeline to obtain an ultrasonic phased array image. The ultrasonic phased array image is divided into several areas to determine the defect status of each area. If the sum of the peak factor, echo amplitude, and propagation delay time of the echo signal in the A-scan waveform in the imaging image of the area is greater than the set threshold and there are linear features in the B-scan and C-scan imaging images, it is determined that there is a crack in the area, where the peak factor refers to the ratio of the peak value of the echo signal to the effective value. If the standard deviation of the echo signal amplitude, peak half-width, and echo propagation time in the A-scan waveform in the imaging image of the area is lower than the set threshold and there are approximately circular dark areas in the B-scan and C-scan imaging images, it is determined that there is a pore in the area. , the approximately circular dark area refers to the area in the image that satisfies both the gray value less than the set threshold and the contour roundness value of the area is within the range of 0.9-1.

1. If the peak and trough values ​​of the echo signal in the A-scan waveform in the imaging image of the area and the standard deviation of the echo amplitude are greater than the set threshold and there are irregular dark areas in the B-scan and C-scan imaging images, it is determined that there are slag inclusions in the area. The irregular dark area refers to the area that satisfies both the gray value less than the set threshold and the contour circumference ratio of the area is greater than 2. The number of types of cracks, slag inclusions, and pores in each area is obtained, which correspond to 0, 1, 2, and 3 respectively, and the corresponding values ​​are 0, t1, t2, and t3 respectively, where t3>t2>t1. The sum of the values ​​of all area types in the ultrasonic phased array imaging image of the oil and gas pipeline is counted and marked as the crack, slag, and pore value of the oil and gas pipeline; The crack complex shape, temperature leakage anomaly and crack-clamp hole value of the oil and gas pipeline are normalized. The crack complex shape of the oil and gas pipeline is used as the upper top side length of the trapezoid, the temperature leakage anomaly of the oil and gas pipeline is used as the lower bottom side length of the trapezoid, and the crack-clamp hole value of the oil and gas pipeline is used as the height of the trapezoid. A trapezoid is established and the area of ​​the identified trapezoid is marked as the pipeline defect value GQX of the oil and gas pipeline.

3. A long-distance oil and gas pipeline inspection and flaw detection method according to claim 2, characterized in that: The steps for analyzing the crack complex and temperature leakage abnormality of the oil and gas pipeline are as follows: The probe is directly coupled to the ground on the oil and gas pipeline through a coupling agent, and an ultrasonic signal is transmitted into the oil and gas pipeline through an electromagnetic ultrasonic flaw detection device to obtain the ultrasonic flaw detector receiving signal information, obtain the standard deviation of the echo amplitude, the spectrum bandwidth of the echo signal, the energy attenuation rate of the echo signal, and the fractal dimension of the echo signal, and sum them to obtain the crack complexity value of the oil and gas pipeline, wherein the fractal dimension of the echo signal is calculated by the box dimension method, and the energy attenuation rate of the echo signal refers to the ratio of the transmitted ultrasonic energy to the energy of the received echo signal; the oil and gas pipeline is detected by an infrared thermal imager, and the oil and gas pipeline is divided into several areas, and the temperature value of each area is obtained. If the temperature value of the area is greater than the set threshold value TT1, the area is corresponding to the material leakage area, and if the temperature value of the area is less than the set threshold value TT2, the area is corresponding to the insulation layer abnormal area, and the proportion of the material leakage area and the insulation layer abnormal area is counted and marked as the oil and gas pipeline temperature leakage abnormal value.

4. A long-distance oil and gas pipeline inspection and flaw detection method according to claim 1, characterized in that: The analysis steps of the auxiliary melt deviation of the oil and gas pipeline are as follows: The compensator of the oil and gas pipeline is treated with a photoelastic coating, and the compensator is divided into several areas. First, the light is incident in a direction perpendicular to the external force compensator of each area through a polarized light field. The change in the optical path difference and the change in the fringe characteristic value are counted and summed to obtain the light difference stripe characteristic change value, where the fringe characteristic value change is the change value of the position, shape, contrast and distance value of the adjacent dark stripes within a certain period of time of the stripe. When the light intensity value of the stripe is lower than the set light intensity threshold, it corresponds to a dark stripe. The direction of the polarized light field is continuously changed. When the light difference stripe characteristic change value corresponding to the polarized light field is less than the set threshold, the stripes formed by the polarized light field are equi-inclined stripes, and the rotation angle zθ of the polarized light field at this time is obtained. c And the angle xθ between the iso-inclined fringe and the x-axis c , where c represents the sequence number of the region, according to the formula Get the principal stress direction β of each region c , the polarized light field makes the light incident in the direction perpendicular to the external force compensator in each area, and obtains the equidistant line fringe series Js c , Wall thickness of each area of ​​oil and gas pipeline compensator b c , the fringe value tw of the coating material c , according to the formula Δσ 0c =Js c ×tw c / b c , and obtain the orthotropic principal stress difference Δσ of each region 0c , the angle θ of the polarizer and analyzer in the rotating polarized light field c , obtain the number of equidistant fringe levels Jx after rotating the polarized light field c According to the formula Δσ c =Jx c ×tw c / (b c ×cosθ c ), and the oblique principal stress difference Δσ of each region is obtained c , establish the equation system Solve the equation to get the principal stress σ1 in each region c and σ2 c ,in According to the formula Get the equivalent stress σe of each area c , the range of principal stress directions in each region and the standard deviation of equivalent stress in each region are counted, and weighted calculation is performed, and multiplied by the corresponding weight factor coefficient to obtain the compensator stress deviation value of the oil and gas pipeline; The compensator stress deviation value of the oil and gas pipeline, marked as bcz, is normalized with the valve gas flow value Qrz, and substituted into the set formula YRP=p1×bcz+p2×Qrz for calculation to obtain the auxiliary stress deviation value YRP of the oil and gas pipeline, where p1 and p2 are the preset proportional factor coefficients of the compensator stress deviation value and the valve gas flow value of the oil and gas pipeline, respectively.

5. A long-distance oil and gas pipeline inspection and flaw detection method according to claim 4, characterized in that: The valve gas melting value analysis steps are as follows: Step 3: Use the edge detection algorithm to detect the edge of the bubble in each bubble motion window, and extract the outline of the bubble, obtain the distance from each pixel point of the bubble outline in the bubble motion window of two adjacent frames to its centroid coordinates, and perform difference calculation to take the absolute value, marked as the bubble wheel mass deviation value of each adjacent two frames of images, and calculate the Hu moment eigenvalue of the bubble motion window in the two adjacent frames of images by the Hu moment method and According to the formula Get the bubble wheel moment difference value lz of each adjacent two frames of images, λ is the set correction factor coefficient, i is the Hu moment eigenvalue number, the value is a positive integer, the maximum value is 7, the bubble wheel mass deviation value of each adjacent two frames of images and the bubble wheel moment difference value of each adjacent two frames of images are summed to get the bubble splitting and melting value of each adjacent two frames of images, the integral value of the bubble splitting value in the continuous image sequence within a certain period of time of each bubble motion window is counted to get the bubble splitting and melting value of each bubble motion window, and the bubble trajectory vector value of each bubble motion window is summed to get the bubble melting value of each bubble motion window; Step 4: Count the average value of the bubble transport value of each bubble motion window, marked as the bubble transport mean value of the bubble motion window, marked as qpj, count the standard value of the bubble transport value of each bubble motion window, marked as the bubble transport fluctuation value of the bubble motion window, marked as qbj, count the ratio of the bubble motion window to all windows, marked as the bubble rate qpl, and substitute it into the set formula model In the calculation, the valve gas melting value Qrz is obtained, wherein a1, a2, a3, a4, a5 and a6 are all preset weight factor coefficients, and a1>a4, a2>a5, a3>a6.

6. A long-distance oil and gas pipeline inspection and flaw detection method according to claim 5, characterized in that: The steps for analyzing the bubble trajectory vector value of each bubble motion window are as follows: Step 1: Use an industrial camera to obtain a continuous image sequence of the valve within a certain period of time, use a filtering algorithm to denoise the image, convert the denoised color image into a grayscale image, divide the grayscale image into several windows, and calculate the optical flow vector of each window pixel. The optical flow vector is the movement direction and speed of the pixel in the image sequence. When the window optical flow amplitude is greater than the set threshold, the corresponding window is a bubble movement window; Step 2: Get the components of the optical flow vector of the jth pixel in the bubble motion window in the x-axis and y-axis directions, marked as fl and y respectively. j x and fl j y , j = 1, 2, ..., J, J is the maximum value of the pixel number, according to the formula Get the centroid coordinates (xz, yz) of each bubble motion window, where (x j ,y j ) is the coordinate of the j-th pixel in the bubble motion window. The bubble motion trajectory of each bubble motion window is obtained by tracking the centroid coordinates of the bubble motion window in the time image sequence, the optical flow vector change of the bubble motion window in the time image sequence is obtained, and the optical flow vector change value of the bubble is obtained. The bubble motion trajectory range of each bubble motion window and the bubble optical flow vector change value are weighted and multiplied by the corresponding weight factor coefficient to obtain the bubble trajectory value of each bubble motion window.

7. A long-distance oil and gas pipeline inspection and flaw detection method according to claim 1, characterized in that: The steps of issuing the corresponding early warning signal analysis are as follows: If the patrol damage comprehensive level value of the oil and gas pipeline is within the patrol damage gradient reference interval TC1, an extremely serious damage signal of the oil and gas pipeline is issued, and measure one is implemented. If the patrol damage comprehensive level value of the oil and gas pipeline is within the patrol damage gradient reference interval TC2, a relatively serious damage signal of the oil and gas pipeline is issued. Measure two is implemented. If the patrol damage comprehensive level value of the oil and gas pipeline is within the patrol damage gradient reference interval TC3, a general damage signal of the oil and gas pipeline is issued. Measure three is implemented. If the patrol damage comprehensive level value of the oil and gas pipeline is within the patrol damage gradient reference interval TC4, a good damage signal of the oil and gas pipeline is issued.

8. A long-distance oil and gas pipeline inspection and flaw detection method according to claim 7, characterized in that: The steps for analyzing the comprehensive damage level of the oil and gas pipeline are as follows: The auxiliary stress deviation value YRP of the oil and gas pipeline, the pipeline defect value GQX of the oil and gas pipeline, and the outer ring identification value WHB of the oil and gas pipeline are normalized and substituted into the set formula YZZ=τ×(tq1×YRP+tq2×GQX) / (tq3×WHB) model to calculate and obtain the patrol damage comprehensive level value YZZ of the oil and gas pipeline, tq1, tq2 and tq3 are all preset weight factor coefficients, and τ is the set correction factor coefficient.

9. A long-distance oil and gas pipeline inspection and flaw detection method according to claim 8, characterized in that: The steps for analyzing the outer ring identification value of the oil and gas pipeline are as follows: Obtain the soil corrosion value, identification pile information loss value, and warning value of the oil and gas pipeline, marked as tf, ylz, and qsl respectively, and use the formula Calculation is performed to obtain the outer ring identification value WHB of the oil and gas pipeline, where g1, g2, and g3 are all set influencing factor coefficients.

10. A long-distance oil and gas pipeline inspection and flaw detection system, characterized in that A long-distance oil and gas pipeline inspection and flaw detection method applied to any one of claims 1 to 9, comprising: The data acquisition module is used to collect auxiliary information, pipeline information, and environmental identification information, and send them to the auxiliary module, pipeline module, and environmental identification module respectively; The auxiliary module is used to receive auxiliary information to determine and analyze the valve bubble movement and compensator stress of the pipeline to obtain the auxiliary stress deviation value of the oil and gas pipeline; The pipeline module is used to receive pipeline information and analyze cracks, temperature distribution, slag inclusions, and pores of the oil and gas pipeline to obtain pipeline defect values ​​of the oil and gas pipeline; The environmental identification module is used to receive environmental identification information and analyze the status of the soil, identification piles, warning tapes and warning signs of the oil and gas pipeline to obtain the outer ring identification value of the oil and gas pipeline; The early warning module is used to receive the auxiliary melt deviation value of the oil and gas pipeline, the pipeline defect value of the oil and gas pipeline, and the outer ring identification value of the oil and gas pipeline, analyze the use status of the oil and gas pipeline, and issue corresponding early warning signals.

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