Method and system for locating the internal structure of an object based on digital ray imaging

Abstract

The present invention provides a method and system for locating the internal structure of an object based on digital radiographic imaging, including: step S1: calibrating a radiographic source and a radiation detector; step S2: measuring the distance between the radiographic source and the radiation detector; step S3: detecting the plane position of the defect and calibrating the defect position, and collecting an image; step S4: framing the defect position, and measuring the defect length on the collected image; step S5: calculating the position of the preset surface of the defect distance detection member according to the workpiece thickness information and the defect depth. The present invention increases the positioning of the defect depth in the digital radiographic detection process, greatly reduces the requirements for personnel experience in the evaluation of digital detection results, enables non-professional personnel to judge the workpiece processing and grinding allowances through the depth information of the defect, and reduces the subsequent processing caused by the previous wrong judgment of the defect depth position.

Description

Technical Field

[0001] The present invention relates to the field of nondestructive testing technology, and in particular, to a method and system for locating the internal structure of an object based on digital radiographic imaging, and more particularly, to a digital radiographic testing method and system for calibrating and measuring the depth of internal defects of an object using digitized radiographic images as material. Background Art

[0002] Digital Radiography (DR) is a non-destructive testing method that uses radiation detectors to convert X-rays and form digital images. It is widely used in the production process of products in important industrial fields such as aviation, aerospace, special equipment, and military industry. During the radiographic imaging process, three-dimensional defects will be flattened. This feature makes this detection method easier to detect area two-dimensional defects, but it also leads to poor sensitivity for depth-directed defects. At present, the evaluation results of the detection image are mainly defect type, defect level or number, and the plane position of the defect. It is impossible to give the detection result of the defect depth position. In the actual post-processing process, it is extremely dependent on the defect depth information. Therefore, it can only rely on the subjective judgment of the defect depth by the inspector, the processing experience of the post-processor of similar products, or the need to use other detection methods to make up for the detection blind spots, all of which increase the uncertainty of product detection.

[0003] Patent document CN108593685A (application number: CN201810183444.1) discloses a digital ray automatic detection device and a detection method thereof, including a control system, the control system is electrically connected to an execution system, the execution system includes a workpiece clamping device, the control system includes a central controller, the central controller is electrically connected to a mobile controller with a contact switch, and the mobile controller is electrically connected to the workpiece clamping device; the mobile controller enables the workpiece clamping device to alternately load and unload multiple workpieces to be inspected, and the mobile controller enables the workpiece clamping device to adjust the transillumination posture of the workpiece to be inspected. However, this application does not locate the depth of the defect. Summary of the invention

[0004] In view of the defects in the prior art, the object of the present invention is to provide a method and system for locating the internal structure of an object based on digital radiographic imaging.

[0005] According to the present invention, a method for locating the internal structure of an object based on digital radiographic imaging includes:

[0006] Step S1: calibrating the radiation source and the radiation detector;

[0007] Step S2: measuring the distance between the radiation source and the radiation detector;

[0008] Step S3: Detect the defect plane position and calibrate the defect position, and collect images;

[0009] Step S4: framing the defect position and measuring the defect length on the captured image;

[0010] Step S5: Calculate the position of the defect distance from the preset surface of the detection member according to the workpiece thickness information and the defect depth.

[0011] Preferably, in step S1:

[0012] Start the digital radiation detection system, calibrate the radiation source and the radiation detector, and make the central radiation beam of the radiation source perpendicular to the detector plane;

[0013] The digital ray detection system includes an X-ray machine system, a radiation detector system, a computer software system, and a detection mechanical control system; the calibration means that the computer software system aligns the central beam of the ray source with the center of the imaging field of view of the radiation detector through the detection mechanical control system so that the center points of the two are coaxial;

[0014] In step S2:

[0015] The distance between the measured radiation source and the radiation detector refers to the distance from the focus of the radiation source to the center of the imaging plane of the detector.

[0016] Preferably, in step S3:

[0017] The defect plane includes: a detection surface a of the inspected workpiece perpendicular to the radiation transmission direction and close to the radiation detector, and a cut surface b of the side of the workpiece closer to the radiation source during the first inspection, and the a surface is parallel to the b surface;

[0018] The detection defect plane position refers to the defect image position confirmed by the digital radiographic detection system through real-time imaging of the inspected part;

[0019] The defect position calibration refers to placing the defect center at the center of the radiation detector imaging field of view during real-time imaging, so that the center beam of the radiation source, the center of the radiation detector imaging field of view, and the defect of the inspected part are coaxial;

[0020] Adjusting process parameters and acquiring images refers to adjusting the parameters of the radiographic detection system, including tube voltage, tube current, and exposure time, to obtain X-ray images of the defects being inspected;

[0021] After detecting the defect plane position on the detection surface a and calibrating the defect position and collecting images, the detection surface b is moved close to the radiation source side and perpendicular to the central ray beam of the radiation source, and the defect plane position is detected and calibrated and images are collected repeatedly to obtain the X-ray image of the defect again.

[0022] Preferably, in step S4:

[0023] Framing the defect position means that the marking tool frames the defect position and makes the marking frame tangent to the defect edge;

[0024] The defect length on the measured image refers to the distance between the two farthest points on the defect calibration frame measured by the measuring tool, and the defect image size under different projection directions of the two collected images.

[0025] Preferably, in step S5:

[0026] The defect depth calculation function H is defined as follows:

[0027]

[0028]

[0029] Among them, HA is the distance from the defect center to the a-plane; HB is the distance from the defect center to the b-plane; X is the distance between the ray source and the radiation detector, A is the defect length on the image obtained by collecting the a-plane, B is the defect length on the image obtained by collecting the b-plane, and D is the thickness of the workpiece.

[0030] According to the present invention, a system for positioning the internal structure of an object based on digital radiographic imaging includes:

[0031] Module M1: Calibrate radiation source and radiation detector;

[0032] Module M2: measuring the distance between the radiation source and the radiation detector;

[0033] Module M3: detect the defect plane position, calibrate the defect position, and collect images;

[0034] Module M4: Frame the defect location and measure the defect length on the acquired image;

[0035] Module M5: Calculate the position of the defect distance from the preset surface of the detection part based on the workpiece thickness information and the defect depth.

[0036] Preferably, in the module M1:

[0037] Start the digital radiation detection system, calibrate the radiation source and the radiation detector, and make the central radiation beam of the radiation source perpendicular to the detector plane;

[0038] The digital ray detection system includes an X-ray machine system, a radiation detector system, a computer software system, and a detection mechanical control system; the calibration means that the computer software system aligns the central beam of the ray source with the center of the imaging field of view of the radiation detector through the detection mechanical control system so that the center points of the two are coaxial;

[0039] In the module M2:

[0040] The distance between the measured radiation source and the radiation detector refers to the distance from the focus of the radiation source to the center of the imaging plane of the detector.

[0041] Preferably, in the module M3:

[0042] The defect plane includes: a detection surface a of the inspected workpiece perpendicular to the radiation transmission direction and close to the radiation detector, and a cut surface b of the side of the workpiece closer to the radiation source during the first inspection, and the a surface is parallel to the b surface;

[0043] The detection defect plane position refers to the defect image position confirmed by the digital radiographic detection system through real-time imaging of the inspected part;

[0044] The defect position calibration refers to placing the defect center at the center of the radiation detector imaging field of view during real-time imaging, so that the center beam of the radiation source, the center of the radiation detector imaging field of view, and the defect of the inspected part are coaxial;

[0045] Adjusting process parameters and acquiring images refers to adjusting the parameters of the radiographic detection system, including tube voltage, tube current, and exposure time, to obtain X-ray images of the defects being inspected;

[0046] After detecting the defect plane position on the detection surface a and calibrating the defect position and collecting images, the detection surface b is moved close to the radiation source side and perpendicular to the central ray beam of the radiation source, and the defect plane position is detected and calibrated and images are collected repeatedly to obtain the X-ray image of the defect again.

[0047] Preferably, in the module M4:

[0048] Framing the defect position means that the marking tool frames the defect position and makes the marking frame tangent to the defect edge;

[0049] The defect length on the measured image refers to the distance between the two farthest points on the defect calibration frame measured by the measuring tool, and the defect image size under different projection directions of the two collected images.

[0050] Preferably, in the module M5:

[0051] The defect depth calculation function H is defined as follows:

[0052]

[0053]

[0054] Among them, HA is the distance from the defect center to the a-plane; HB is the distance from the defect center to the b-plane; X is the distance between the ray source and the radiation detector, A is the defect length on the image obtained by collecting the a-plane, B is the defect length on the image obtained by collecting the b-plane, and D is the thickness of the workpiece.

[0055] Compared with the prior art, the present invention has the following beneficial effects:

[0056] 1. The present invention increases the positioning of defect depth during digital radiographic detection, greatly reduces the requirements for personnel experience in judging digital detection results, and enables non-professional personnel to judge workpiece processing and grinding allowances based on defect depth information, thereby reducing subsequent processing caused by previous misjudgments of defect depth and position;

[0057] 2. The present invention uses digital radiographic image materials and digital measurement methods, which enables the present invention to have high accuracy and high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0059] Figure 1 This is a workflow diagram of a detection system for a method for locating the internal structure of an object based on digital ray imaging of the present invention;

[0060] Figure 2 A schematic diagram of a method and device for locating the internal structure of a weld based on digital radiographic imaging according to the present invention;

[0061] Figure 3 The present invention is a schematic diagram of the principle of a method for locating the internal structure of a weld based on digital radiographic imaging. DETAILED DESCRIPTION

[0062] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0063] Embodiment 1:

[0064] According to the present invention, a method for locating the internal structure of an object based on digital radiographic imaging is provided. Figure 1-Figure 3 As shown, including:

[0065] Step S1: calibrating the radiation source and the radiation detector;

[0066] Specifically, in step S1:

[0067] Start the digital radiation detection system, calibrate the radiation source and the radiation detector, and make the central radiation beam of the radiation source perpendicular to the detector plane;

[0068] The digital ray detection system includes an X-ray machine system, a radiation detector system, a computer software system, and a detection mechanical control system; the calibration means that the computer software system aligns the central beam of the ray source with the center of the imaging field of view of the radiation detector through the detection mechanical control system so that the center points of the two are coaxial;

[0069] Step S2: measuring the distance between the radiation source and the radiation detector;

[0070] In step S2:

[0071] The distance between the measured radiation source and the radiation detector refers to the distance from the focus of the radiation source to the center of the imaging plane of the detector.

[0072] Step S3: Detect the defect plane position and calibrate the defect position, and collect images;

[0073] Specifically, in step S3:

[0074] The defect plane includes: a detection surface a of the inspected workpiece perpendicular to the radiation transmission direction and close to the radiation detector, and a cut surface b of the side of the workpiece closer to the radiation source during the first inspection, and the a surface is parallel to the b surface;

[0075] The detection defect plane position refers to the defect image position confirmed by the digital radiographic detection system through real-time imaging of the inspected part;

[0076] The defect position calibration refers to placing the defect center at the center of the radiation detector imaging field of view during real-time imaging, so that the center beam of the radiation source, the center of the radiation detector imaging field of view, and the defect of the inspected part are coaxial;

[0077] Adjusting process parameters and acquiring images refers to adjusting the parameters of the radiographic detection system, including tube voltage, tube current, and exposure time, to obtain X-ray images of the defects being inspected;

[0078] After detecting the defect plane position on the detection surface a and calibrating the defect position and collecting images, the detection surface b is moved close to the radiation source side and perpendicular to the central ray beam of the radiation source, and the defect plane position is detected and calibrated and images are collected repeatedly to obtain the X-ray image of the defect again.

[0079] Step S4: framing the defect position and measuring the defect length on the captured image;

[0080] Specifically, in step S4:

[0081] Framing the defect position means that the marking tool frames the defect position and makes the marking frame tangent to the defect edge;

[0082] The defect length on the measured image refers to the distance between the two farthest points on the defect calibration frame measured by the measuring tool, and the defect image size under different projection directions of the two collected images.

[0083] Step S5: Calculate the position of the defect distance from the preset surface of the detection member according to the workpiece thickness information and the defect depth.

[0084] Specifically, in step S5:

[0085] The defect depth calculation function H is defined as follows:

[0086]

[0087]

[0088] Among them, HA is the distance from the defect center to the a-plane; HB is the distance from the defect center to the b-plane; X is the distance between the ray source and the radiation detector, A is the defect length on the image obtained by collecting the a-plane, B is the defect length on the image obtained by collecting the b-plane, and D is the thickness of the workpiece.

[0089] Embodiment 2:

[0090] Embodiment 2 is a preferred example of Embodiment 1, and is used to illustrate the present invention in more detail.

[0091] Those skilled in the art may understand the method for locating the internal structure of an object based on digital radiation imaging provided by the present invention as a specific implementation of the system for locating the internal structure of an object based on digital radiation imaging, that is, the system for locating the internal structure of an object based on digital radiation imaging may be implemented by executing the step flow of the method for locating the internal structure of an object based on digital radiation imaging.

[0092] According to the present invention, a system for positioning the internal structure of an object based on digital radiographic imaging includes:

[0093] Module M1: Calibrate radiation source and radiation detector;

[0094] Specifically, in the module M1:

[0095] Start the digital radiation detection system, calibrate the radiation source and the radiation detector, and make the central radiation beam of the radiation source perpendicular to the detector plane;

[0096] The digital ray detection system includes an X-ray machine system, a radiation detector system, a computer software system, and a detection mechanical control system; the calibration means that the computer software system aligns the central beam of the ray source with the center of the imaging field of view of the radiation detector through the detection mechanical control system so that the center points of the two are coaxial;

[0097] Module M2: measuring the distance between the radiation source and the radiation detector;

[0098] In the module M2:

[0099] The distance between the measured radiation source and the radiation detector refers to the distance from the focus of the radiation source to the center of the imaging plane of the detector.

[0100] Module M3: detect the defect plane position, calibrate the defect position, and collect images;

[0101] Specifically, in the module M3:

[0102] The defect plane includes: a detection surface a of the inspected workpiece perpendicular to the radiation transmission direction and close to the radiation detector, and a cut surface b of the side of the workpiece closer to the radiation source during the first inspection, and the a surface is parallel to the b surface;

[0103] The detection defect plane position refers to the defect image position confirmed by the digital radiographic detection system through real-time imaging of the inspected part;

[0104] The defect position calibration refers to placing the defect center at the center of the radiation detector imaging field of view during real-time imaging, so that the center beam of the radiation source, the center of the radiation detector imaging field of view, and the defect of the inspected part are coaxial;

[0105] Adjusting process parameters and acquiring images refers to adjusting the parameters of the radiographic detection system, including tube voltage, tube current, and exposure time, to obtain X-ray images of the defects being inspected;

[0106] After detecting the defect plane position on the detection surface a and calibrating the defect position and collecting images, the detection surface b is moved close to the radiation source side and perpendicular to the central ray beam of the radiation source, and the defect plane position is detected and calibrated and images are collected repeatedly to obtain the X-ray image of the defect again.

[0107] Module M4: Frame the defect location and measure the defect length on the acquired image;

[0108] Specifically, in the module M4:

[0109] Framing the defect position means that the marking tool frames the defect position and makes the marking frame tangent to the defect edge;

[0110] The defect length on the measured image refers to the distance between the two farthest points on the defect calibration frame measured by the measuring tool, and the defect image size under different projection directions of the two collected images.

[0111] Module M5: Calculate the position of the defect distance from the preset surface of the detection part based on the workpiece thickness information and the defect depth.

[0112] Specifically, in the module M5:

[0113] The defect depth calculation function H is defined as follows:

[0114]

[0115]

[0116] Among them, HA is the distance from the defect center to the a-plane; HB is the distance from the defect center to the b-plane; X is the distance between the ray source and the radiation detector, A is the defect length on the image obtained by collecting the a-plane, B is the defect length on the image obtained by collecting the b-plane, and D is the thickness of the workpiece.

[0117] Embodiment 3:

[0118] Embodiment 3 is a preferred example of Embodiment 1, and is used to illustrate the present invention in more detail.

[0119] Digital radiography is a non-destructive detection method for internal defects that converts X-rays through radiation detectors and forms digital images. Since the digital radiography detection image is a two-dimensional projection of the object structure on the detector plane, it is impossible to obtain the depth information of the detected defect along the direction of the ray. The present invention discloses a method for locating the position of the internal structure of an object based on digital radiography, which belongs to the field of non-destructive testing technology. It solves the problems that the defect depth judgment results in current digital radiography are overly dependent on the subjective experience of the inspectors, and the defect positioning in the depth direction is difficult and the positioning error is large. Professional inspectors can use this method to determine the defect depth position, so that post-processing personnel can judge the workpiece processing and grinding allowance through accurate defect depth information, reducing the subsequent processing caused by the previous error in the judgment of the defect depth position. The method establishes a model for the internal defect depth positioning method. By measuring the distance between the radiation source and the radiation detector, the projected defect length obtained by two transilluminations, and the workpiece thickness information, the distance between the defect center and the surface of the inspected workpiece can be calculated, thereby achieving the purpose of positioning the internal structure. The method includes the following steps: (1) starting the digital radiation detection system, calibrating the radiation source and the radiation detector, and making the central beam of the radiation source perpendicular to the detector plane; (2) measuring the distance X between the radiation source and the radiation detector; (3) detecting the defect plane position; (4) calibrating the defect position on the a surface; (5) adjusting the process parameters and capturing images; (6) repeating the above steps (3) to (5) on the b surface of the inspected workpiece; (7) framing the defect position; (8) measuring the defect lengths A and B on the image obtained by two captures; and (9) calculating the position of the defect distance from the a surface and the b surface of the inspected workpiece based on the workpiece thickness information D and the defect depth calculation function H.

[0120] The technical problem to be solved by the present invention is to overcome the problems existing in the existing digital ray detection methods, such as the difficulty in locating defects in the depth direction and the large positioning error, and to reduce the reliance of detection personnel on subjective experience in judging the depth of defects.

[0121] In order to solve the above technical problems, the present invention proposes a method for locating the internal structure of an object based on digital X-ray imaging. The method establishes a model for the internal defect depth positioning method. By measuring the distance between the X-ray source and the radiation detector, the length of the projected defect obtained by two transilluminations, and the thickness information of the workpiece, the distance between the center of the defect and the surface of the inspected part can be calculated, thereby achieving the purpose of locating the internal structure. It solves the current problems in digital X-ray detection, such as excessive reliance on the subjective experience of the inspectors in the depth judgment results, difficulty in locating the defects in the depth direction, and large positioning errors. Professional inspectors can use this method to determine the defect depth position, so that post-processing personnel can judge the workpiece processing and grinding allowances through accurate defect depth information, reduce the subsequent processing caused by the previous errors in the judgment of the defect depth position, and reduce the impact of the subjective experience of the inspectors. The specific technical scheme of the present invention is as follows:

[0122] A method for locating the internal structure of an object based on digital radiographic imaging comprises the following steps:

[0123] (1) Start the digital radiation detection system, calibrate the radiation source and the radiation detector, and make the central beam of the radiation source perpendicular to the detector plane;

[0124] (2) Measure the distance X between the radiation source and the radiation detector;

[0125] (3) Detect the plane position of the defect;

[0126] (4) a-surface defect position calibration;

[0127] (5) Adjust process parameters and collect images;

[0128] (6) Repeat steps (3) to (5) for side b of the test piece;

[0129] (7) Frame the defect location;

[0130] (8) Measure the defect lengths A and B on the image twice;

[0131] (9) Calculate the position of the defect distance between the a-side and b-side of the detection part based on the workpiece thickness information D and the defect depth calculation function H.

[0132] For example, if there is a situation where an irregular structure is detected: 1. One side is a plane, and the other side relative to the plane is an irregular surface (arc or other); 2. Both sides are irregular surfaces.

[0133] In the first case, surface a is selected as usual, and surface b is a section at the point farthest from the irregular side to surface a, and the section is parallel to surface a.

[0134] In the second case, select a section on one side first, and select the other side in the same way as the b-side in the first case.

[0135] Furthermore, a preferred method is that the digital radiation detection system in step (1) includes an X-ray machine system, a radiation detector system, a computer software system, and a detection mechanical control system; and the calibration refers to the computer software system aligning the central beam of the radiation source with the center of the imaging field of view of the radiation detector through the detection mechanical control system so that the center points of the two are coaxial.

[0136] Furthermore, a preferred method is that the distance between the radiation source and the radiation detector measured in step (2) refers to the distance from the focus of the radiation source to the center of the imaging plane of the detector.

[0137] Furthermore, a preferred method is that the detection of the defect plane position in step (3) refers to confirming the defect image position of the inspected part through real-time imaging by a digital X-ray detection system.

[0138] Furthermore, a preferred method is that the a-plane in step (4) refers to the detection plane of the inspected part which is perpendicular to the radiation penetration direction and close to the radiation detector, and is the section plane of the side of the workpiece which is closer to the imaging plate during the first detection; the defect position calibration refers to placing the defect center at the center of the imaging field of the radiation detector during real-time imaging, so that the center beam of the radiation source, the center of the imaging field of the radiation detector, and the defect of the inspected part are coaxial.

[0139] Furthermore, a preferred method is that the adjusting of process parameters in step (5) and collecting images refer to adjusting parameters such as tube voltage, tube current, exposure time, etc. of the X-ray imaging detection system to obtain an X-ray image of the defect being inspected.

[0140] Furthermore, a preferred method is that the step (6) of repeating the above steps (2) to (5) on the b side of the inspection piece means that the b side of the inspection piece is close to the radiation source side and perpendicular to the central beam of the radiation source, and steps (2) to (5) are repeated to obtain an X-ray image of the defect again;

[0141] The b-plane is the section of the workpiece on the side closer to the radiation source during the first detection, wherein the a-plane and the b-plane are parallel.

[0142] Furthermore, a preferred method is that the framing of the defect position in step (7) refers to using a marking tool to frame the defect position and making the marking frame tangent to the defect edge.

[0143] Furthermore, the preferred method is that the defect length on the image obtained by measuring the two acquisitions in step (8) refers to the distance between the two farthest points on the defect calibration frame measured by the measuring tool, that is, the defect image size under different projection directions of the two images.

[0144] Furthermore, the preferred method is that the defect depth is calculated by a formula, which is the object to be achieved by the present invention. Defect depth is a relative concept, and the results are different for different selected surfaces (sides): HA is taken as the reference for surface a; HB is taken as the reference for surface b. There is a certain relationship between the original length of the defect, the projection length, and the defect depth: the ratio of the defect length to the projection length is equal to the ratio of HA to the thickness of the workpiece, but the actual defect length cannot be obtained, only the defect projection length in each exposure direction can be obtained. Therefore, after exposure to two opposite surfaces, two three-way relationship equations can be obtained, and the function H can be obtained by combining them.

[0145] The defect depth calculation function H in step (9) is defined as follows:

[0146]

[0147]

[0148] Where HA is the distance between the defect center and the a-plane; HB is the distance between the defect center and the b-plane; X is the distance between the ray source and the radiation detector;

[0149] Embodiment 4:

[0150] Embodiment 4 is a preferred example of Embodiment 1, and is used to illustrate the present invention in more detail.

[0151] A preferred embodiment of the present invention provides a method for locating the internal structure of an object based on digital radiographic imaging. This method is applied to the internal pores of a fusion welded butt joint. The specific processing flow is as follows: Figure 1 As shown:

[0152] (1) Start the digital radiation detection system, and align the central beam of the radiation source vertically with the center position of the radiation detector's field of view through the cross positioning fixture. During this process, it is necessary to ensure that the projection of the cross positioning fixture on the imaging plate does not deform. Then, the relative distance X between the two is collected and recorded through the detection mechanical control system;

[0153] (2) Start real-time imaging, find the defect plane position in the inspected object, and place the surface A of the inspected object close to the radiation detector while slowly entering the field of view of the radiation detector;

[0154] (3) Adjust the process parameters through the image shown in real-time imaging to ensure that the acquired image does not suffer from overexposure or low signal-to-noise ratio, and move the defect to the center of the radiation detector according to the imaging field of view detection mechanical control system;

[0155] (4) The computer software system controls the digital imaging software to collect images;

[0156] (5) Without changing the positions of the radiation source and the radiation detector, the detection member is adjusted by the detection machine control software so that the b surface faces the radiation detector, and the above detection steps (3) to (5) are repeated;

[0157] (6) The inspector uses the calibration tool in the digital imaging software to frame the defect position and ensure that the defect is tangent to the edge of the calibration frame;

[0158] (7) Use digital imaging software to measure the distance values ​​A and B between the two farthest points of the defect on the image;

[0159] (8) After inputting the workpiece thickness information D, the system calculates the position of the defect from the a and b surfaces of the inspection part according to the defect depth calculation function H. The function is as follows:

[0160]

[0161] Where HA is the distance between the defect center and the a-plane; HB is the distance between the defect center and the b-plane. Figure 3shown.

[0162] (9) Based on the values ​​calculated by the system, the defect depth and location as well as the required processing amount under each surface can be known, which can greatly improve the detection accuracy and reliability in engineering applications.

[0163] Those skilled in the art know that, in addition to implementing the system, device and its various modules provided by the present invention in a purely computer-readable program code, it is entirely possible to implement the same program in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers and embedded microcontrollers by logically programming the method steps. Therefore, the system, device and its various modules provided by the present invention can be considered as a hardware component, and the modules included therein for implementing various programs can also be considered as structures within the hardware component; the modules for implementing various functions can also be considered as both software programs for implementing the method and structures within the hardware component.

[0164] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A method for locating the internal structure of an object based on digital radiographic imaging, characterized in that: include: Step S1: calibrating the radiation source and the radiation detector; Step S2: measuring the distance between the radiation source and the radiation detector; Step S3: Detect the defect plane position and calibrate the defect position, and collect images; Step S4: framing the defect position and measuring the defect length on the captured image; Step S5: Calculate the position of the defect from the preset surface of the detection part according to the workpiece thickness information and the defect depth; In step S5: The defect attempt calculation function H is used to calculate the defect, and the position defect depth calculation function H from the preset surface of the inspection piece is defined as follows: Among them, HA is the distance from the defect center to the a-plane; HB is the distance from the defect center to the b-plane; X is the distance between the ray source and the radiation detector, A is the defect length on the image obtained by collecting the a-plane, B is the defect length on the image obtained by collecting the b-plane, and D is the thickness of the workpiece.

2. The method for locating the internal structure of an object based on digital radiographic imaging according to claim 1, characterized in that: In step S1: Start the digital radiation detection system, calibrate the radiation source and the radiation detector, and make the central radiation beam of the radiation source perpendicular to the detector plane; The digital ray detection system includes an X-ray machine system, a radiation detector system, a computer software system, and a detection mechanical control system; the calibration means that the computer software system aligns the central beam of the ray source with the center of the imaging field of view of the radiation detector through the detection mechanical control system so that the center points of the two are coaxial; In step S2: The distance between the measured radiation source and the radiation detector refers to the distance from the focus of the radiation source to the center of the imaging plane of the detector.

3. The method for locating the internal structure of an object based on digital ray imaging according to claim 1, characterized in that: In step S3: The defect plane includes: a detection surface a of the inspected workpiece perpendicular to the radiation transmission direction and close to the radiation detector, and a cut surface b of the side of the workpiece closer to the radiation source during the first inspection, and the a surface is parallel to the b surface; The detection defect plane position refers to the defect image position confirmed by the digital radiographic detection system through real-time imaging of the inspected part; The defect position calibration refers to placing the defect center at the center of the radiation detector imaging field of view during real-time imaging, so that the center beam of the radiation source, the center of the radiation detector imaging field of view, and the defect of the inspected part are coaxial; Adjusting process parameters and acquiring images refers to adjusting the parameters of the radiographic detection system, including tube voltage, tube current, and exposure time, to obtain X-ray images of the defects being inspected; After detecting the defect plane position on the detection surface a and calibrating the defect position and collecting images, the detection surface b is moved close to the radiation source side and perpendicular to the central ray beam of the radiation source, and the defect plane position is detected and calibrated and images are collected repeatedly to obtain the X-ray image of the defect again.

4. The method for locating the internal structure of an object based on digital ray imaging according to claim 1, characterized in that: In step S4: Framing the defect position means that the marking tool frames the defect position and makes the marking frame tangent to the defect edge; The defect length on the measured image refers to the distance between the two farthest points on the defect calibration frame measured by the measuring tool, and the defect image size under different projection directions of the two collected images.

5. A system for positioning the internal structure of an object based on digital radiographic imaging, characterized in that: include: Module M1: Calibrate radiation source and radiation detector; Module M2: measuring the distance between the radiation source and the radiation detector; Module M3: detect the defect plane position, calibrate the defect position, and collect images; Module M4: Frame the defect location and measure the defect length on the acquired image; Module M5: Calculate the position of the defect distance from the preset surface of the detection part according to the workpiece thickness information and the defect depth; In the module M5: The defect attempt calculation function H is used to calculate the defect, and the position defect depth calculation function H from the preset surface of the inspection piece is defined as follows: Among them, HA is the distance from the defect center to the a-plane; HB is the distance from the defect center to the b-plane; X is the distance between the ray source and the radiation detector, A is the defect length on the image obtained by collecting the a-plane, B is the defect length on the image obtained by collecting the b-plane, and D is the thickness of the workpiece.

6. The system for positioning the internal structure of an object based on digital radiographic imaging according to claim 5, characterized in that: In the module M1: Start the digital radiation detection system, calibrate the radiation source and the radiation detector, and make the central radiation beam of the radiation source perpendicular to the detector plane; The digital ray detection system includes an X-ray machine system, a radiation detector system, a computer software system, and a detection mechanical control system; the calibration means that the computer software system aligns the central beam of the ray source with the center of the imaging field of view of the radiation detector through the detection mechanical control system so that the center points of the two are coaxial; In the module M2: The distance between the measured radiation source and the radiation detector refers to the distance from the focus of the radiation source to the center of the imaging plane of the detector.

7. The system for positioning the internal structure of an object based on digital radiographic imaging according to claim 5, characterized in that: In the module M3: The defect plane includes: a detection surface a of the inspected workpiece perpendicular to the radiation transmission direction and close to the radiation detector, and a cut surface b of the side of the workpiece closer to the radiation source during the first inspection, and the a surface is parallel to the b surface; The detection defect plane position refers to the defect image position confirmed by the digital radiographic detection system through real-time imaging of the inspected part; The defect position calibration refers to placing the defect center at the center of the radiation detector imaging field of view during real-time imaging, so that the center beam of the radiation source, the center of the radiation detector imaging field of view, and the defect of the inspected part are coaxial; Adjusting process parameters and acquiring images refers to adjusting the parameters of the radiographic detection system, including tube voltage, tube current, and exposure time, to obtain X-ray images of the defects being inspected; After detecting the defect plane position on the detection surface a and calibrating the defect position and collecting images, the detection surface b is moved close to the radiation source side and perpendicular to the central ray beam of the radiation source, and the defect plane position is detected and calibrated and images are collected repeatedly to obtain the X-ray image of the defect again.

8. The system for positioning the internal structure of an object based on digital radiographic imaging according to claim 5, characterized in that: In the module M4: Framing the defect position means that the marking tool frames the defect position and makes the marking frame tangent to the defect edge; The defect length on the measured image refers to the distance between the two farthest points on the defect calibration frame measured by the measuring tool, and the defect image size under different projection directions of the two collected images.

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