A measuring device and method for double-wall penetrating irradiation inspection and positioning ray source

Abstract

A measuring device and method for positioning a radiation source for double-wall transmissive radiation inspection comprises an angle ruler, the angle ruler is an angle ruler for measuring from 0 to 90 degrees, the position at a right angle is 0 point, the 0° direction is perpendicular to the surface of the inspected object, the 90° direction is parallel to the surface of the inspected object, and a rotating laser pen is fixed at the 0 point position; by designing an easy-to-carry and easy-to-operate device with the function of accurately measuring the focal length of radiation inspection and the deviation angle of the radiation source (or the deviation distance of the radiation source), it is convenient for radiation inspectors or radiation inspection quality control personnel to accurately measure and locate the focal length of radiation inspection and the deviation angle of the radiation source (or the deviation distance of the radiation source), thereby improving the accuracy of the key parameters of double-wall double-shadow or double-wall single-shadow radiation inspection: focal length and radiation source deviation angle (or radiation source deviation distance), thereby improving the sensitivity of radiation inspection and the defect detection rate.

Description

Technical Field

[0001] The invention relates to the field of measuring devices, and in particular to a measuring device and method for double-wall transillumination ray inspection and positioning of ray sources. Background Art

[0002] Technical Analysis

[0003] As a volumetric nondestructive testing method, radiographic inspection is widely used in the domestic power industry and manufacturing industry. However, due to its own technical characteristics, changes in process parameters such as focal length and radiation penetration direction can easily affect the sensitivity and defect detection rate of radiographic inspection, as shown below:

[0004] 1. The focal length of the X-ray inspection directly affects the geometric unsharpness, which in turn affects the sensitivity of the X-ray inspection:

[0005]

[0006] Where: d f - the focal size of the radiation source;

[0007] F——the distance from the radiation source to the film (focal length);

[0008] b——the distance from the defect to the film;

[0009] 2. A very small change in the radiation inspection penetration direction (i.e., the deviation angle of the radiation source, or the deviation distance of the radiation source) may lead to the missed detection of certain small defects, especially dangerous surface defects such as cracks.

[0010] Analysis of actual implementation

[0011] Domestic nuclear power plants basically use steel tape measures to measure key parameters such as focal length and radiation source deviation angle (or radiation source deviation distance) for double-wall double-shadow or double-wall single-shadow radiation inspections, among which: the focal length is measured by a steel tape measure from the vertical distance from the surface of the inspected object to the radiation source; the deviation angle is measured by a steel tape measure from the horizontal distance from the radiation source to the center of the inspected area (this distance, i.e., the radiation source deviation distance, is calculated by converting the deviation angle and the focal length).

[0012] Since there is no fixed vertical or horizontal reference when measuring with a tape measure, and because the radiation source itself has a certain size and there may be errors in human measurement, the final measurement results may have errors, especially in:

[0013] (1) During vertical transillumination, the radiation source cannot be accurately fixed at a position directly above the center of the object being inspected;

[0014] (2) The deviation angle of the radiation source measured by the tape measure during deviated transillumination (i.e., the converted deviation distance of the radiation source) has a certain error compared with the calculated value.

[0015] Analysis of actual execution results

[0016] The X-ray inspection results of the nuclear power plant showed that some minor defects were not discovered compared with the results of the adjacent inspection (all such displays found so far are record displays). Technical analysis found that the main reason for the difference in the two inspection results was due to the slight difference in the deviation angle of the radiation source (i.e. the deviation distance of the radiation source).

[0017] For dangerous flat displays, the technical characteristics of X-ray inspection itself determine that such displays can only be discovered when the radiation source is at a specific angle, that is, the radiation beam is parallel to the display expansion direction. Therefore, once the angle of the radiation source changes, it is very easy to lead to missed detection of dangerous flat displays.

[0018] In addition, the geometric unsharpness limit values ​​for radiographic inspections are generally clearly specified in the specifications. However, in the actual implementation process, due to objective factors such as work efficiency requirements and site conditions, the geometric unsharpness of some welds is selected to be slightly below the critical value required by the specifications (i.e., just meeting the specifications). If there is an error between the actual focal length and the theoretical calculated value, or if it is slightly less than the calculated value, it can easily lead to the geometric unsharpness not meeting the specifications.

[0019] In summary, for double-wall double-shadow or double-wall single-shadow X-ray inspection technology, the sensitivity of X-ray inspection and the defect detection rate can be improved by improving the accuracy of key parameters: focal length and X-ray source deviation angle (or X-ray source deviation distance). Summary of the invention

[0020] The purpose of the present invention is to design a device that is easy to carry and easy to operate and has the function of accurately measuring the focal length of radiation inspection and the deviation angle of the radiation source (or the deviation distance of the radiation source), so as to facilitate radiation inspection personnel or radiation inspection quality control personnel to accurately measure and locate the focal length of radiation inspection and the deviation angle of the radiation source (or the deviation distance of the radiation source), thereby improving the accuracy of the key parameters of double-wall double-shadow or double-wall single-shadow radiation inspection: focal length and radiation source deviation angle (or radiation source deviation distance), thereby improving the sensitivity of radiation inspection and the defect detection rate.

[0021] The technical solution of the present invention is as follows: a measuring device for double-walled penetrating irradiation inspection and positioning ray source, comprising an angle ruler, the angle ruler is an angle ruler for measuring from 0 degrees to 90 degrees, the right angle position is 0 point, the 0° direction is perpendicular to the surface of the inspected object, the 90° direction is parallel to the surface of the inspected object, and a rotating laser pen is fixed at the 0 point position;

[0022] A fixed scale is fixed on the 90° side of the angle ruler, and an adjustable laser pen is installed on the end of the fixed scale;

[0023] The telescopic ruler is fixed on the 0° side of the angle ruler, and at the same time, a laser pen is installed and fixed on the end of the telescopic ruler.

[0024] A rotating laser pointer that rotates from 0-90° is fixed at the 0 o'clock position.

[0025] The adjustable laser pointer moves horizontally left and right on a fixed scale.

[0026] The telescopic ruler is extended and retracted back and forth in a direction perpendicular to the surface of the object being inspected.

[0027] The adjustable laser pen points to the vertical direction, and the fixed laser pen points to the horizontal direction; the common intersection of the adjustable laser pen, the fixed laser pen and the rotating laser pen is the radiation source 7.

[0028] A method for measuring a double-wall transillumination radiation inspection technology to accurately locate a radiation source comprises the following steps:

[0029] S1: Calculate the radiographic inspection parameters: the focal length of the radiation source f1, the radiation source deviation angle θ or the radiation source deviation distance x;

[0030] S2: Set the length of the telescopic ruler = f2;

[0031] S3: Rotate the laser pen to the position corresponding to the scale θ, or move the adjustable laser pen to the position corresponding to the scale = x;

[0032] S4: Turn on the fixed laser pointer and the rotating laser pointer at the same time;

[0033] S5: Place the device on the surface of the object to be inspected according to the attached figure, and move the radiation source so that the radiation source is at the intersection of the fixed laser pen and the rotating laser pen.

[0034] A measurement method for accurately locating a radiation source using a double-wall transillumination radiation inspection technology also includes S6: if the purpose is to verify whether the position of the radiation source is correct, repeat S1-S4 to verify whether the radiation source is at the intersection of a fixed laser pen and a rotating laser pen.

[0035] The remarkable effects of the present invention are:

[0036] 1) It has strong functionality and can accurately measure the line inspection focal length, the deviation angle of the radiation source, and the deviation distance of the radiation source at the same time, which greatly reduces the human uncertainty factors when measuring the above parameters and improves work efficiency;

[0037] 2) High efficiency. This device can improve the accuracy of the key parameters of double-wall double-shadow or double-wall single-shadow X-ray inspection: focal length and X-ray source deviation angle (or X-ray source deviation distance), thereby improving X-ray inspection sensitivity and defect detection rate;

[0038] 3) Easy to operate. The device only needs to set the corresponding parameters on the scale with scale according to the calculation data. The operation is simple and has no boundaries;

[0039] 4) Easy to carry. The focal length measuring scale of this device is designed to be retractable, which greatly reduces the size of the device. The deviation angle of the X-ray inspection is small, and the length of the horizontal scale is basically sufficient at 100mm. For example, if this device is used in a nuclear power plant, the size is designed to be 200mm*100mm, which is sufficient for on-site use and is very convenient to carry.

[0040] 5) It is widely used and can be applied to the positioning of radiation sources in most double-wall double-shadow or double-wall single-shadow radiographic inspections in the entire NDE industry, and is also suitable for quality supervisors to accurately monitor radiographic inspection parameters;

[0041] The economic cost is low, the materials required for the device are common, and the assembly and processing are simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Attached Figure 1 This is a schematic diagram of the measurement device for double-walled penetrating irradiation inspection and positioning of the ray source.

[0043] In the figure: 1—angle ruler; 2—fixed laser pen; 3—rotating laser pen;

[0044] 4—adjustable laser pen; 5—telescopic ruler; 6—fixed scale; 7—radiation source 8—object to be detected. DETAILED DESCRIPTION

[0045] A measuring device for double-walled penetrating radiation inspection and positioning radiation source, comprising an angle ruler 1, the angle ruler 1 is an angle ruler for measuring from 0 to 90 degrees, the right angle position is 0 point, the 0° direction is perpendicular to the surface of the inspected object 8, and the 90° direction is parallel to the surface of the inspected object 8. A rotating laser pen 3 that can rotate from 0 to 90° is fixed at the 0 point position;

[0046] A fixed scale 6 with scales is fixed on the 90° side of the angle ruler 1 for accurately measuring the focal length of the radiation source. At the same time, an adjustable laser pen 4 is installed at the end of the fixed scale 6, and the adjustable laser pen 4 can move horizontally left and right on the fixed scale 6; considering the convenience of on-site carrying, scales 6 of various specifications can be designed according to actual needs (such as 300mm, 500mm, 800mm, 1000mm specifications, etc., the focal length used in nuclear power plants is generally within 800mm).

[0047] A telescopic ruler 5 is fixed on the 0° side of the angle ruler 1 , and at the same time, a laser pen 2 is fixedly installed on the end of the telescopic ruler 5 . The telescopic ruler 5 can be telescoped back and forth in a direction perpendicular to the surface of the object 8 to be inspected.

[0048] The adjustable laser pen 4 points to the vertical direction, the fixed laser pen 2 points to the horizontal direction, and the common intersection of the adjustable laser pen 4, the fixed laser pen 2 and the rotating laser pen 3 is a radiation source 7;

[0049] The working process of this device is:

[0050] S1: Calculate the radiographic inspection parameters: the focal length f1 of the radiation source 7, the radiation source deviation angle θ or the radiation source deviation distance x;

[0051] S2: Set the length of the telescopic ruler 5 to f2;

[0052] S3: Rotate the laser pen 3 to the position corresponding to the scale θ, or move the adjustable laser pen 4 to the position corresponding to the scale = x;

[0053] S4: Turn on the fixed laser pen 2 and the rotating laser pen 3 (or the adjustable laser pen 4) at the same time;

[0054] S5: Place the device on the surface of the object to be inspected according to the attached figure, and move the radiation source so that the radiation source is at the intersection of the fixed laser pen 2 and the rotating laser pen 3 (or the adjustable laser pen 4).

[0055] S6: If the purpose is to verify whether the position of the radiation source is correct, repeat steps (1) to (4) to verify whether the radiation source is at the intersection of the fixed laser pen 2 and the rotating laser pen 3 (or the adjustable laser pen 4).

Claims

1. A measuring device for double-walled penetrating irradiation inspection and positioning ray source, characterized in that: The invention comprises an angle ruler (1), wherein the angle ruler (1) is an angle ruler for measuring from 0 to 90 degrees, the right angle position is 0 point, the 0° direction is perpendicular to the surface of the object to be inspected (8), and the 90° direction is parallel to the surface of the object to be inspected (8), and a rotating laser pen (3) that rotates from 0 to 90 degrees is fixed at the 0 point position; A scale (6) is fixed on the 90° side of the angle ruler (1), and an adjustable laser pen (4) is installed on the end of the fixed scale (6); A telescopic ruler (5) is fixed on the 0° side of the angle ruler (1), and a laser pen (2) is installed and fixed on the end of the telescopic ruler (5); The laser pen (4) can be adjusted to move horizontally left and right on the fixed scale (6); The telescopic ruler (5) is telescopically extended and retracted in a direction perpendicular to the surface of the object to be inspected (8); The adjustable laser pen (4) points in a vertical direction, and the fixed laser pen (2) points in a horizontal direction; the common intersection of the adjustable laser pen (4), the fixed laser pen (2) and the rotating laser pen (3) is a radiation source (7).

2. A method for measuring a double-walled penetrating ray inspection and positioning ray source, using the double-walled penetrating ray inspection and positioning ray source measuring device as claimed in claim 1, characterized in that: The following steps are involved: S1: Calculate the radiographic inspection parameters: the focal length f1 of the radiation source (7), the radiation source deviation angle θ or the radiation source deviation distance x; S2: Set the length of the telescopic ruler (5) = f2; S3: Rotate the laser pen (3) to the position corresponding to the scale θ, or move the adjustable laser pen (4) to the position corresponding to the scale = x; S4: Turn on the fixed laser pen (2) and the rotating laser pen (3) at the same time; S5: placing the device on the surface of the object to be inspected, and moving the radiation source so that the radiation source is located at the intersection of the fixed laser pen (2) and the rotating laser pen (3).

3. A method for measuring a double-wall penetrating irradiation inspection positioning ray source according to claim 2, characterized in that: The method further comprises S6: if the position of the radiation source is to be verified to be correct, repeating steps S1-S4 to verify whether the radiation source is at the intersection of the fixed laser pen (2) and the rotating laser pen (3).

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