Intelligent nondestructive inspection device for steel structure

Abstract

The invention discloses an intelligent nondestructive flaw detection device for a steel structure, and relates to the technical field of flaw detection tools for steel structures. Through cooperation of the controller and the connector, the X-ray power can be adjusted at any time, the flaw detection condition can be observed at any time, and the flaw detection effect is improved; the thickness and density data of the steel structure are detected through the monitoring module, the ray attenuation coefficient is calculated through the analysis module, the needed X-ray intensity is determined, and radiation hazards caused by blind increase of power are avoided; the appearance of the steel structure is detected through a sensor, defects such as protrusions and recesses on the surface are accurately judged, and the influence of the defects on X-ray imaging is further analyzed; through detailed imaging offset analysis steps, a coordinate system is established to calculate ray propagation path change and imaging plane position deviation, and then the translation amount of a ray source is calculated to carry out position adjustment, so that complete and accurate imaging can still be obtained when bulges exist on the surface of the steel structure, and the adaptability of the flaw detection device to the surface of the complex steel structure is improved.

Description

Technical Field

[0001] The invention relates to the technical field of steel structure flaw detection tools, and in particular to an intelligent non-destructive flaw detection device for steel structures. Background Art

[0002] Steel structure flaw detection equipment is a device specially used to detect potential defects or damages in steel structures. Common flaw detection equipment includes ultrasonic flaw detectors, X-ray flaw detectors and eddy current flaw detectors. X-ray flaw detectors usually consist of an X-ray transmitter, a cable and a detector head. When performing X-ray detection, the operator places the detection head close to the surface of the steel structure, then starts the X-ray transmitter to release X-rays to detect the steel structure. During short-distance detection, one person can complete the operation, but during long-distance detection, one person usually needs to hold the detection head close to the steel structure while another person controls the X-ray transmitter, which may sometimes cause information asynchrony. In the prior art, when operators use X-ray emission devices to perform flaw detection on steel structures, in order to ensure that the X-rays can penetrate the steel structure, they usually adjust the X-ray power to a higher level, resulting in the X-rays still having a higher intensity after passing through the steel structure, making the radiation intensity diffused to the surrounding environment higher, causing adverse effects on the health of surrounding operators; The residue or protrusions on the surface of the steel structure due to welding or other factors will cause the attenuation coefficient of X-rays to change, reducing the intensity of the rays required for imaging, resulting in unclear imaging, affecting the correct judgment of the internal damage of the steel structure. The protrusions also affect the refraction angle of the X-rays, making it impossible for the complete imaging to fall on the correct area, making the actual imaging incomplete and unable to judge the internal damage of the steel structure; Therefore, improvements are made based on the above problems. Summary of the invention

[0003] The purpose of the present invention is to solve the shortcomings of the prior art and to propose an intelligent non-destructive flaw detection device for steel structures.

[0004] In order to achieve the above-mentioned object, the present invention adopts the following technical scheme: an intelligent non-destructive flaw detection device for steel structure, comprising a tank body, a tank cover is installed on the top surface of the tank body, a connecting block is fixedly connected to the middle of the top surface of the tank cover, a supporting plate is horizontally installed in the middle of the top surface of the connecting block, handles are installed on both sides of the supporting plate, and a controller is installed on the top surface of the supporting plate, and a connecting assembly is provided at the lower end of the tank body; The controller is also provided with a monitoring module, an analysis module and a processing module; The monitoring module detects the thickness data and density data of the steel structure, detects the distance data between the sensor and the steel structure, and transmits the detected thickness data, density data and distance data to the analysis module; The analysis module analyzes and processes the thickness data, density data and spacing data transmitted by the monitoring module, calculates the ray attenuation coefficient of the steel structure, determines the required X-ray intensity, and calculates the X-ray intensity adjustment value according to the changes on the surface of the steel structure, and transmits the adjustment value to the processing module; The processing module receives the adjustment value transmitted by the analysis module, and then adjusts the position of the ray source according to the adjustment value.

[0005] Preferably, the connecting assembly comprises a bottom ring horizontally arranged at the lower end of the tank body, the four ends above the inner wall of the bottom ring are fixedly connected with guide seats, a guide opening is opened in the middle of the top surface of the guide seat, and a guide rod is arranged in the guide opening.

[0006] Preferably, a baffle is fixedly connected to the bottom surface of the guide rod, the baffle is placed at the lower end of the guide seat, and a support rod is vertically fixedly connected to the top surface of the guide rod, and the upper ends of multiple support rods are all installed at the lower end of the outer side of the tank body.

[0007] Preferably, the diameter of the support rod is larger than the diameter of the guide rod, and a spring is provided between the support rod and the guide seat, the spring is sleeved on the guide rod, and one end of the spring abuts against the bottom surface of the support rod and the other end abuts against the top surface of the guide seat.

[0008] Preferably, a connector is provided between the plurality of support rods, the upper end of the connector is connected to the tank body, and a cable is connected to one side of the connector, and a flaw detection head is installed at the other end of the cable.

[0009] Preferably, a plurality of equidistant probes are installed inside the other end of the flaw detection head, and a magnetic ring is installed on the inner wall of the other end of the flaw detection head.

[0010] Preferably, the analysis steps of the steel structure attenuation coefficient are as follows: Step 1: Measure the thickness data of the steel structure, and then obtain the steel structure sample to obtain the density data of the steel structure; prepare several standard samples of the material to be tested with known thickness (d1, d2, d3...), irradiate the samples of different thicknesses with the same X-ray source, and record the ray intensity I1, I2, I3... received by the detector during each irradiation; the ray intensity after penetration I=Io*A, A represents the base e of the exponent -ud, Io is the initial ray intensity, and d is the steel structure thickness data; Step 2: For samples of different thicknesses, we can obtain In(I1 / I2)=u*(d2-d1). Substituting the known thickness data and ray intensity data into the formula, we can calculate the specific value of the attenuation coefficient u. Step 3: Obtain the minimum imaging intensity data of X-ray imaging. According to the ray attenuation formula, the X-ray initial intensity data required under the minimum imaging intensity can be calculated.

[0011] Preferably, the analysis steps of the influence of the steel structure appearance on X-rays are as follows: Step 1: Clean the appearance of the steel structure sample to be detected, and then detect the distance of the steel structure sample transported on the conveyor belt through an infrared distance sensor at a fixed position. If the detected distance data is not equal to the set distance data, it is determined that there is a defect in the appearance of the steel structure; if the detected distance data becomes smaller and the distance change data exceeds the preset distance threshold, it indicates that there is a convex part on the surface of the steel structure; if the detected distance data becomes larger and the distance change data exceeds the preset distance threshold, it indicates that there is a concave part on the surface of the steel structure. Step 2: Analyze the distance detection data corresponding to the convex part. Sort the detected distance data according to the acquisition time, then calculate the difference between adjacent detection data, and compare the calculated differences. If the difference between the calculated differences is less than the preset comparison threshold, it is determined that the convexity is regular, and the length data r and height data h of the convexity are detected. It is determined that the variable GB of the ray propagation path = h*h / r. If GB < d / 10, it is determined that the influence of the convexity on imaging is small and a clear image can be obtained; otherwise, it is determined that the influence of the convexity on imaging is large, and the imaging offset amount is analyzed. Step 3: Detect the depth data of the depression on the surface of the steel structure. If the depression depth data is less than 1 / 10 of the steel structure thickness data, it is determined that the influence of the depression on imaging is small and a clear image can be obtained; otherwise, through the ray attenuation formula, calculate the change amount of the attenuation coefficient caused by the depression, and then obtain the changed attenuation coefficient.

[0012] Preferably, the analysis steps of the X-ray imaging offset amount caused by the convexity are as follows: Step 1: Establish a three-dimensional rectangular coordinate system. Place the surface of the steel structure on the xy plane, with the z-axis perpendicular to the surface of the steel structure. The position of the ray source is set as S(xs, ys, zs), the position of the detector (imaging plane) is set as D(xd, yd, zd), and the center position of the convexity is set as P(xp, yp, zp); ideally, the length L0 of the ray from the source point S to the detector D is equal to the square root of the sum of the squares of the differences of the two coordinate items. When the ray is reflected by the convexity, let the reflection point be R(xr, yr, zr). The length of the ray from the source point S to the reflection point R is calculated in the same way and denoted as L1, and the length from the reflection point R to the detector D is denoted as L2. Then the total length data L = L1 + L2. Step 2: The coordinates of the reflection point R are obtained through the intersection equation of the ray and the convex surface, and then L1 and L2 are calculated; the path length change GBL=L-L0. On the imaging plane, the position deviations GBx and GBy are related to the ray propagation path length change GBL and the relative position of the detector and the ray source. Assuming that the detector plane is parallel to the plane, the position deviation on the imaging plane is GBx=GBL*(xd-xs) / L0, GBy=GBL*(yd-ys) / L0; Step 2: Calculate the translation YX of the ray source in the x direction by the principle of similar triangles. Assuming that the translation of the ray source will cause the displacement change ratio in the same direction on the imaging plane to be k, then GBx=k*YX. From this, the specific value of the displacement change ratio k can be calculated. Then, based on the position deviations GBx and GBy, the translation of the ray source in the x and y directions can be calculated respectively.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1. The cooperation of the spring and the guide rod makes it easy to buffer the X-ray device inside the device when putting it down, avoiding damage to the X-ray device and ensuring the flaw detection effect; the cooperation of the controller and the connector makes it easy to adjust the power of the X-ray at any time and observe the flaw detection situation at any time, thus improving the flaw detection effect; the cooperation of the flaw detection head and the magnetic ring makes it easy to adsorb the flaw detection head on the steel structure, so that it is easy for one person to complete the operation and improve work efficiency; 2. The monitoring module detects the thickness and density data of the steel structure, and the analysis module calculates the ray attenuation coefficient and determines the required X-ray intensity. It can accurately adjust the X-ray power according to the actual situation of the steel structure, avoiding the radiation hazards caused by blindly increasing the power, while ensuring clear imaging and effectively improving the accuracy of flaw detection; 3. Use infrared distance sensors to detect the appearance of steel structures, accurately determine surface defects such as protrusions and depressions, and further analyze their impact on X-ray imaging; through detailed imaging offset analysis steps, establish a coordinate system to calculate the changes in ray propagation paths and imaging plane position deviations, and then calculate the ray source translation for position adjustment, ensuring that complete and accurate imaging can still be obtained when there are protrusions on the surface of the steel structure, thereby improving the adaptability of the flaw detection device to complex steel structure surfaces. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 It is a schematic diagram of the overall three-dimensional structure of the present invention; Figure 2 It is a schematic diagram of the overall three-dimensional structure of the present invention when viewed from above; Figure 3 It is a schematic diagram of the three-dimensional structure of the connection between the controller and the tank cover of the present invention; Figure 4 It is a schematic diagram of the three-dimensional structure of the flaw detection head of the present invention; Figure 5 For the present invention Figure 2 A schematic diagram of the enlarged structure of the middle A part; Figure 6 It is a system flow chart of the present invention.

[0015] Serial numbers in the figure: 1. tank body; 2. tank cover; 3. connecting block; 4. supporting plate; 5. handle; 6. controller; 7. support rod; 8. bottom ring; 9. guide seat; 10. guide rod; 11. baffle; 12. spring; 13. connector; 14. cable; 15. flaw detection head; 16. probe; 17. magnetic ring. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0017] Example: See Figure 1-6 , an intelligent nondestructive flaw detection device for steel structure in the present invention comprises a tank body 1, a tank cover 2 is installed on the top surface of the tank body 1, a connecting block 3 is fixedly connected to the middle of the top surface of the tank cover 2, a supporting plate 4 is horizontally installed in the middle of the top surface of the connecting block 3, handles 5 are installed on both sides of the supporting plate 4, and a controller 6 is installed on the top surface of the supporting plate 4, and a connecting assembly is provided at the lower end of the tank body 1; the X-ray device is conveniently stored through the tank body 1; the X-ray device is conveniently disassembled and installed through the tank cover 2; the supporting plate 4 is conveniently installed through the connecting block 3; the handle 5 and the controller 6 are conveniently installed through the supporting plate 4; the device is conveniently moved through the handle 5; the size of the ray and the flaw detection are conveniently adjusted through the controller 6; the connecting assembly comprises a bottom ring 8 horizontally arranged at the lower end of the tank body 1, the four ends above the inner wall of the bottom ring 8 are fixedly connected to a guide seat 9, a guide opening is opened in the middle of the top surface of the guide seat 9, and a guide rod 10 is arranged in the guide opening; the positioning device is conveniently located through the bottom ring 8, and the guide rod 10 is conveniently connected through the guide seat 9; the moving direction of the tank body 1 is conveniently controlled through the guide rod 10.

[0018] The controller 6 is also provided with a monitoring module, an analysis module and a processing module; When the X-ray power is appropriate, it can make different density areas inside the steel structure (such as defective parts and normal metal parts) produce obvious grayscale differences on the X-ray film; for the porosity defects in the welds of steel structures, X-rays with sufficient power can make the pores appear as black circular images on the film, which form a sharp contrast with the gray-white image of the surrounding normal weld metal, making it easier to identify; if the power is too high, it may cause overexposure, reduce the grayscale level of the image, and reduce the contrast, just like an overexposed photo, the details of the defect may be "submerged" in a white image, which is not conducive to the accurate determination of the defect; while too low power will make the image darker as a whole, and some small defects may not be observed due to insufficient grayscale; The monitoring module measures the thickness data of the steel structure, and then obtains the steel structure sample to obtain the density data of the steel structure; prepare a series of standard samples of the materials to be tested with known thickness (d1, d2, d3...), and the thickness accuracy is prepared by high-precision mechanical processing methods, and the thickness error is within ±0.1mm. Use the same X-ray source, fix the energy of the ray and the position of the detector, and irradiate samples of different thicknesses. The energy of the fixed ray is achieved by fixing the tube voltage and tube current; record the ray intensity I1, I2, I3... received by the detector during each irradiation; according to the ray attenuation formula, the ray intensity after penetration I=Io*A, A represents the base e of the exponent -ud, Io is the initial ray intensity, and d is the steel structure thickness data; for samples of different thicknesses, In(I1 / I2)=u*(d2-d1) can be obtained, and the known thickness data and ray intensity data are substituted into the formula to calculate the specific value of the attenuation coefficient u; the minimum imaging intensity data of X-ray imaging is obtained, and according to the ray attenuation formula, the X-ray initial intensity data required at the minimum imaging intensity can be calculated.

[0019] The appearance of the steel structure sample to be inspected is cleaned, and then the distance of the steel structure sample transmitted on the conveyor belt is detected by the infrared distance sensor at a fixed position. If the detected distance data is not equal to the set distance data, it is determined that there are defects in the appearance of the steel structure; if the detected distance data becomes smaller and the distance change data exceeds the preset distance threshold, it indicates that there are convex parts on the surface of the steel structure; if the detected distance data becomes larger and the distance change data exceeds the preset distance threshold, it indicates that there are concave parts on the surface of the steel structure; Analyze the distance detection data corresponding to the convex part, sort the detected distance data according to the acquisition time, then calculate the difference between adjacent detection data, and compare the calculated differences. If the difference between the calculated differences is less than the preset comparison threshold, it is determined that the convex is regular. Detect the length data r and height data h of the convex, and determine that the variable GB of the ray propagation path is h*h / r. If GB < d / 10, it is determined that the influence of the convex on imaging is small and a clear image can be obtained; otherwise, it is determined that the influence of the convex on imaging is large and the imaging offset is analyzed. Establish a three-dimensional rectangular coordinate system, place the steel structure surface on the xy plane, with the z-axis perpendicular to the steel structure surface. Set the ray source position as S(xs, ys, zs), the detector (imaging plane) position as D(xd, yd, zd), and the convex center position as P(xp, yp, zp). Ideally, the length L0 of the ray from the source point S to the detector D is equal to the square root of the sum of the squares of the differences of the coordinates of the two points. When the ray is reflected by the convex, let the reflection point be R(xr, yr, zr). The length of the ray from the source point S to the reflection point R is calculated in the same way and denoted as L1, and the length from the reflection point R to the detector D is denoted as L2. Then the total length data L = L1 + L2. The coordinates of the reflection point R can be obtained through the intersection equation of the ray and the convex surface (by联立 the ray equation and the convex surface equation), and then L1 and L2 can be calculated. The path length change GBL = L - L0. According to the principle of similar triangles, on the imaging plane, the position deviations GBx and GBy are related to the ray propagation path length change GBL and the relative positions of the detector and the ray source. Assuming the detector plane is parallel to the plane, the position deviation on the imaging plane GBx = GBL*(xd - xs) / L0, GBy = GBL*(yd - ys) / L0. Calculate the translation amount YX of the ray source in the x direction through the principle of similar triangles. Assume that the translation of the ray source causes a proportional change in the displacement in the same direction on the imaging plane as k. Then GBx = k*YX, from which the specific value of the displacement change ratio k can be calculated. Then, according to the position deviations GBx and GBy, the translation amounts of the ray source in the x and y directions can be calculated respectively. Adjust the position of the ray source according to the translation amount to obtain a complete X-ray image. The depression will change the effective thickness of the steel structure in this area. Detect the depth data of the depression on the steel structure surface. If the depression depth data is less than 1 / 10 of the steel structure thickness data, it is determined that the influence of the depression on imaging is small and a clear image can be obtained; otherwise, through the ray attenuation formula, calculate the change amount of the attenuation coefficient caused by the depression, and then obtain the changed attenuation coefficient.

[0020] In the present invention, a baffle 11 is fixedly connected to the bottom surface of the guide rod 10, and the baffle 11 is placed at the lower end of the guide seat 9, and a support rod 7 is vertically fixedly connected to the top surface of the guide rod 10, and the upper ends of multiple support rods 7 are installed at the lower end of the outer side of the tank body 1; the baffle 11 prevents the guide rod 10 from being separated from the guide seat 9; the tank body 1 is conveniently connected through the support rod 7; the diameter of the support rod 7 is larger than the diameter of the guide rod 10, and a spring 12 is provided between the support rod 7 and the guide seat 9, the spring 12 is sleeved on the guide rod 10, and one end of the spring 12 abuts on the bottom surface of the support rod 7, and the other end abuts on the top surface of the guide seat 9; the spring 12 is convenient to The tank body 1 is buffered when it is lowered; a connector 13 is provided between the plurality of support rods 7, the upper end of the connector 13 is connected to the tank body 1, and a cable 14 is connected to one side of the connector 13, and a flaw detection head 15 is installed at the other end of the cable 14; the connector 13 is used to release X-rays; the cable 14 is used to conduct X-rays; the flaw detection head 15 is used to detect whether there are flaws on the steel structure; a plurality of equidistant probes 16 are installed inside the other end of the flaw detection head 15, and a magnetic ring 17 is installed on the inner wall of the other end of the flaw detection head 15; the probe 16 is used to detect the steel structure; the magnetic ring 17 is used to adsorb on the steel structure.

[0021] Working principle: When the present invention is used, firstly, the device is moved to the place where inspection is required by the handles 5 at both ends of the device. When it is moved to the place where inspection is required, the device is oriented so that the bottom ring 8 contacts the bottom surface first, and the support rod 7 is pushed downward by the gravity of the tank body 1 and the upper end controller 6, thereby controlling the guide rod 10 to move downward, and then compressing the spring 12, so as to achieve buffering of the X-ray device inside the tank body 1, and then one end of the cable 14 is connected to the connector 13 at the lower end of the tank body 1, and then the flaw detection head 15 connected at the other end is abutted against the surface of the steel structure to be inspected, and the flaw detection head 15 is adsorbed on the surface of the steel structure by the internal magnetic ring 17 of the flaw detection head 15, so that the flaw detection head 15 is fixed on the surface of the steel structure, and then the controller 6 is started to release X-rays, and then the flaw detection head 15 releases X-rays, so as to detect whether there are scars on the steel structure; when the inspection is completed, the controller 6 is stopped, and then the flaw detection head 15 can be removed.

[0022] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An intelligent non-destructive flaw detection device for steel structures, comprising a tank body (1), characterized in that: The top surface of the tank body (1) is mounted with a tank cover (2), the middle portion of the top surface of the tank cover (2) is fixedly connected with a connecting block (3), the middle portion of the top surface of the connecting block (3) is horizontally mounted with a supporting plate (4), handles (5) are mounted on both sides of the supporting plate (4), and a controller (6) is mounted on the top surface of the supporting plate (4), and a connecting assembly is provided at the lower end of the tank body (1); The controller (6) is also provided with a monitoring module, an analysis module and a processing module; The monitoring module detects the thickness data and density data of the steel structure, detects the distance data between the sensor and the steel structure, and transmits the detected thickness data, density data and distance data to the analysis module; The analysis module analyzes and processes the thickness data, density data and spacing data transmitted by the monitoring module, calculates the ray attenuation coefficient of the steel structure, determines the required X-ray intensity, and calculates the X-ray intensity adjustment value according to the changes on the surface of the steel structure, and transmits the adjustment value to the processing module; The processing module receives the adjustment value transmitted by the analysis module, and then adjusts the position of the ray source according to the adjustment value.

2. The intelligent non-destructive flaw detection device for steel structure according to claim 1, characterized in that: The connection assembly comprises a bottom ring (8) horizontally arranged at the lower end of the tank body (1), the four ends above the inner wall of the bottom ring (8) are fixedly connected to a guide seat (9), a guide opening is opened in the middle of the top surface of the guide seat (9), and a guide rod (10) is arranged in the guide opening.

3. The intelligent non-destructive flaw detection device for steel structure according to claim 2, characterized in that: The bottom surface of the guide rod (10) is fixedly connected with a baffle (11), the baffle (11) is placed at the lower end of the guide seat (9), and the top surface of the guide rod (10) is vertically fixedly connected with a support rod (7), and the upper ends of a plurality of support rods (7) are all mounted on the lower end of the outer side of the tank body (1).

4. The intelligent non-destructive flaw detection device for steel structure according to claim 3 is characterized in that: The diameter of the support rod (7) is greater than the diameter of the guide rod (10), and a spring (12) is provided between the support rod (7) and the guide seat (9), the spring (12) being sleeved on the guide rod (10), and one end of the spring (12) abuts against the bottom surface of the support rod (7), and the other end abuts against the top surface of the guide seat (9).

5. The intelligent non-destructive flaw detection device for steel structures according to claim 3 is characterized in that: A connector (13) is provided between the plurality of support rods (7), the upper end of the connector (13) is connected to the tank body (1), and a cable (14) is connected to one side of the connector (13), and a flaw detection head (15) is installed at the other end of the cable (14).

6. The intelligent non-destructive flaw detection device for steel structure according to claim 5, characterized in that: A plurality of equally spaced probes (16) are installed inside the other end of the flaw detection head (15), and a magnetic ring (17) is installed on the inner wall of the other end of the flaw detection head (15).

7. The intelligent nondestructive flaw detection device for steel structures according to claim 1 is characterized in that: The analysis steps of the steel structure attenuation coefficient are as follows: Step 1: Measure the thickness data of the steel structure, and then obtain the steel structure sample to obtain the density data of the steel structure; prepare several standard samples of the material to be tested with known thickness (d1, d2, d3...), irradiate the samples of different thicknesses with the same X-ray source, and record the ray intensity I1, I2, I3... received by the detector during each irradiation; the ray intensity after penetration I=Io*A, A represents the base e of the exponent -ud, Io is the initial ray intensity, and d is the steel structure thickness data; Step 2: For samples of different thicknesses, In(I1 / I2)=u*(d2 - d1) can be obtained. Substitute the known thickness data and ray intensity data into the formula to calculate the specific value of the attenuation coefficient u. Step 3: Obtain the lowest imaging intensity data of X-ray imaging. According to the ray attenuation formula, calculate the initial X-ray intensity data required at the lowest imaging intensity.

8. The intelligent nondestructive flaw detection device for steel structures according to claim 7 is characterized in that: The analysis steps of the influence of the steel structure appearance on X-rays are as follows: Step 1: Clean the appearance of the steel structure sample to be detected. Then, use an infrared distance sensor at a fixed position to detect the distance of the steel structure sample transported on the conveyor belt. If the detected distance data is not equal to the set distance data, it is determined that there are defects in the appearance of the steel structure. If the detected distance data becomes smaller and the distance change data exceeds the preset distance threshold, it indicates that there is a convex part on the surface of the steel structure. If the detected distance data becomes larger and the distance change data exceeds the preset distance threshold, it indicates that there is a concave part on the surface of the steel structure. Step 2: Analyze the distance detection data corresponding to the convex part. Sort the detected distance data according to the acquisition time, then calculate the difference between adjacent detection data, and compare the calculated differences. If the difference between the calculated differences is less than the preset comparison threshold, it is determined that the convexity is regular. Detect the length data r and height data h of the convexity, and determine that the change amount GB of the ray propagation path is h*h / r. If GB < d / 10, it is determined that the influence of the convexity on imaging is small and clear imaging can be obtained; otherwise, it is determined that the influence of the convexity on imaging is large and the imaging offset amount is analyzed. Step 3: Detect the depth data of the concave part on the surface of the steel structure. If the concave depth data is less than 1 / 10 of the steel structure thickness data, it is determined that the influence of the concavity on imaging is small and clear imaging can be obtained; otherwise, calculate the change amount of the attenuation coefficient caused by the concavity through the ray attenuation formula, and then obtain the changed attenuation coefficient.

9. The intelligent non-destructive flaw detection device for steel structure according to claim 8, characterized in that: The analysis steps of the X-ray imaging offset amount caused by the convexity are as follows: Step 1: Establish a three-dimensional rectangular coordinate system. Place the surface of the steel structure on the xy plane, with the z-axis perpendicular to the surface of the steel structure. Set the ray source position as S(xs, ys, zs), the detector (imaging plane) position as D(xd, yd, zd), and the convex center position as P(xp, yp, zp). Ideally, the length L0 of the ray from the source point S to the detector D is equal to the square root of the sum of the squares of the differences of the coordinates of the two points. When the ray is reflected by the convexity, let the reflection point be R(xr, yr, zr). The length of the ray from the source point S to the reflection point R is calculated in the same way and denoted as L1, and the length from the reflection point R to the detector D is denoted as L2. Then the total length data L = L1 + L2. Step 2: Obtain the coordinates of the reflection point R through the intersection equation of the ray and the convex surface, and then calculate L1 and L2. The path length change GBL=L-L0. On the imaging plane, the position deviations GBx and GBy are related to the ray propagation path length change GBL and the relative position of the detector and the ray source. Assuming that the detector plane is parallel to the plane, the position deviations on the imaging plane are GBx=GBL*(xd-xs) / L0, GBy=GBL*(yd-ys) / L0. Step 2: Calculate the translation YX of the ray source in the x direction by the principle of similar triangles. Assuming that the translation of the ray source will cause the displacement change ratio in the same direction on the imaging plane to be k, then GBx=k*YX. From this, the specific value of the displacement change ratio k can be calculated. Then, based on the position deviations GBx and GBy, the translation of the ray source in the x and y directions can be calculated respectively.

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