Reference block for performing eddy current flaw detection on welding seam of framework and manufacturing method of reference block

Abstract

The invention discloses a reference block for performing eddy current flaw detection on a welding seam of a framework and a manufacturing method of the reference block, and relates to the technical field of flaw detection. The test block body comprises a first connecting piece and a second connecting piece, and the first connecting piece and the second connecting piece are fixed together through welding; the test block body is provided with a first artificial defect and a second artificial defect; the first artificial defect and the second artificial defect are analyzed and determined according to actual measurement failure of the framework; a paint spraying covering layer is sprayed on the outer surface of the test block body, the paint spraying covering layer is the same as a paint layer on a framework to be detected, and the paint spraying covering layer covers the first artificial defect and the second artificial defect. The manufacturing method comprises the following steps: S1, preparing the test block body; s2, making an artificial defect; and S3, paint spraying treatment. The device can provide verification conditions for eddy current flaw detection sensitivity calibration and assist in improving the detection efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of flaw detection, in particular to a comparison test block for performing eddy current flaw detection on a frame weld and a test block manufacturing method. Background Art

[0002] Magnetic particle inspection (MPI) is used to detect surface and near-surface weld defects on newly manufactured bogie frame welds. However, MPI has strict requirements for the surface being inspected. Paint, welding slag, oil, and other factors that could affect the inspection are not permitted. Therefore, MPI can only be performed on newly manufactured, pre-painted parts.

[0003] However, for finished vehicle frames already in operation, those that have been painted cannot be inspected using magnetic particle inspection because the paint covers the welds. Alternatively, the inspected surface must be depainted. Furthermore, if the depainted areas are inspected, they will need to be repainted. However, even partial painting cannot meet the painting process requirements and can cause the paint to peel during operation. Furthermore, magnetic particle inspection is also infeasible for welds with limited design space. Eddy current testing, a nondestructive testing technique that uses electromagnetic induction, is primarily used to detect surface and near-surface defects in metal and conductive materials. Eddy current spot weld probes can penetrate any area within a limited design space and do not require paint removal. Therefore, eddy current testing can be used as an alternative to magnetic particle inspection. However, to achieve targeted inspection of specific areas, eddy current testing requires the preparation of physical comparison test blocks. Summary of the Invention

[0004] The purpose of the present invention is to provide a comparison test block and a test block manufacturing method for eddy current testing of frame welds, so as to solve the problems existing in the above-mentioned prior art, provide verification conditions for eddy current testing sensitivity calibration, and assist in improving detection efficiency.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The present invention provides a comparison test block for performing eddy current testing on a frame weld, comprising a test block body; the test block body comprises a first connecting member and a second connecting member, the first connecting member and the second connecting member are fixed together by welding, and the welding process of the first connecting member and the second connecting member is the same as the welding process of the same position on the frame to be inspected; a first artificial defect and a second artificial defect are provided on the test block body; the first artificial defect and the second artificial defect are both determined based on the measured failure analysis of the frame; a paint covering layer is sprayed on the outer surface of the test block body, the paint covering layer is the same as the paint layer on the frame to be inspected, and the paint covering layer covers the first artificial defect and the second artificial defect.

[0007] Preferably, the first artificial defect is a first arcuate groove, and the second artificial defect is a second arcuate groove; the depth of the first arcuate groove is 0.5 mm, and the depth of the second arcuate groove is 1 mm.

[0008] Preferably, the first arcuate groove and the second arcuate groove are both located at the weld toe position of the corresponding weld.

[0009] Preferably, the first arcuate groove and the second arcuate groove are both formed by wire cutting.

[0010] The present invention also provides a method for making a test block for eddy current testing of a frame weld based on any one of the above items, comprising the following steps:

[0011] S1, cutting the test block body from a prepared and unpainted frame;

[0012] S2, obtaining defect locations through on-site frame defect measurement analysis and frame defect failure analysis, and setting the first artificial defect and the second artificial defect on the test block body;

[0013] S3, spray painting the test block body having the first artificial defect and the second artificial defect, using a finished product frame spray painting process to form the paint covering layer on the surface of the test block body.

[0014] Compared with the prior art, the present invention has achieved the following technical effects:

[0015] The comparison test block provided by the present invention is used for eddy current testing of frame welds. By simulating the key features of real frame welds on the test block body, a standardized calibration benchmark is provided for the sensitivity calibration of eddy current testing equipment to ensure the accuracy and consistency of the test results; the artificial defects are designed based on the measured failure analysis results of the frame, simulating typical defects that may occur in actual service, so that the calibration is closer to the actual detection needs; the same paint layer as the frame is sprayed to cover the artificial defects, simulating the surface state during actual detection, and avoiding the interference of the paint layer on the eddy current signal being ignored; the eddy current point weld probe is calibrated by the comparison test block, and detection can be achieved without stripping the paint on the detection part on the frame, and the eddy current point weld probe can be extended into any part of the design structure with limited space for detection.

[0016] The present invention provides a test block production method for a comparison test block for eddy current testing of frame welds. The test block body is formed by cutting from a real frame, the parent material remains consistent, the welding state is truly restored, and the welding position is consistent, which can avoid detection signal distortion caused by geometric errors when the test block is manually processed; artificial defects are set based on actual measurement analysis, so that the defect distribution of the test block is highly consistent with the actual failure risk, ensuring that the verification conditions are close to the actual detection needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 A schematic diagram of a comparison test block provided by the present invention being cut out on a frame for eddy current testing of the weld seam connecting the upper gusset plate and the crossbeam tube of the frame;

[0019] Figure 2 For Figure 1 Schematic diagram of the crack location of the corresponding weld on the foundation;

[0020] Figure 3 For Figure 1 Front view of the comparison test block made on the basis;

[0021] Figure 4 for Figure 3 Left side view of the structure;

[0022] Figure 5 for Figure 3 Right side view of the structure;

[0023] Figure 6 for Figure 3Top view of the structure.

[0024] In the figure: 1-gusset plate; 2-crossbeam tube; 3-first artificial defect; 4-second artificial defect. DETAILED DESCRIPTION

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0026] The purpose of the present invention is to provide a comparison test block and a test block manufacturing method for eddy current flaw detection of frame welds, so as to solve the problems existing in the prior art, provide verification conditions for eddy current flaw detection sensitivity calibration, and assist in improving detection efficiency.

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] Example 1

[0029] This embodiment provides a comparative test block for eddy current testing of frame welds, such as Figures 1 to 6 As shown, it includes a test block body; the test block body includes a first connecting member and a second connecting member, the first connecting member and the second connecting member are fixed together by welding, and the welding process of the first connecting member and the second connecting member is the same as the welding process of the same position on the frame to be tested; a first artificial defect 3 and a second artificial defect 4 are provided on the test block body; the first artificial defect 3 and the second artificial defect 4 are both determined based on the measured failure analysis of the frame; the outer surface of the test block body is sprayed with a paint covering layer, the paint covering layer is the same as the paint layer on the frame to be tested, and the paint covering layer covers the first artificial defect 3 and the second artificial defect 4.

[0030] By simulating the key features of the real frame weld on the test block body, a standardized calibration benchmark is provided for the sensitivity calibration of the eddy current testing equipment to ensure the accuracy and consistency of the test results; the artificial defects are designed based on the actual failure analysis results of the frame, simulating typical defects that may occur in actual service, so that the calibration is closer to the actual detection needs; the same paint layer as the frame is sprayed to cover the artificial defects, simulating the surface state during actual detection, and avoiding the interference of the paint layer on the eddy current signal being ignored; the eddy current point weld probe is calibrated by comparing the test blocks, which can achieve detection without stripping the paint on the detection part of the frame, and the eddy current point weld probe can be extended into any part of the design structure with limited space for detection (specifically, the eddy current point weld probe is an existing equipment, which is a special equipment for detecting parts with limited space).

[0031] Specifically, the setting of the comparison test block provides a prerequisite and favorable condition for the sensitivity calibration of eddy current flaw detection. The detection sensitivity is high and can detect tiny defects (0.5mm deep cracks). No false detection or missed detection will occur during the inspection, thus ensuring product quality. The inspection is carried out under harsh conditions at the vehicle depot survey site, and the inspection speed is fast. After the sensitivity calibration of the physical comparison test block produced before work starts, eddy current flaw detection can complete the detection of small defects within seconds, which is suitable for rapid inspection of workpieces, improves work efficiency, and reduces the workload of inspection personnel.

[0032] Specifically, such as Figures 1 to 6 As shown, it is a structural display of a comparison test block used for eddy current testing of the connection weld between the crossbeam tube 2 and the gusset plate 1 on the subway car frame.

[0033] Among the optional solutions of this embodiment, it is more preferred that Figures 4 to 6 As shown, the first artificial defect 3 is a first arcuate groove, and the second artificial defect 4 is a second arcuate groove; the depth of the first arcuate groove is 0.5 mm, and the depth of the second arcuate groove is 1 mm.

[0034] Among the optional solutions of this embodiment, it is more preferred that Figure 6 As shown, the first arcuate groove and the second arcuate groove are both located at the weld toe position of the corresponding weld.

[0035] In an optional solution of this embodiment, preferably, the first arcuate groove and the second arcuate groove are both formed by wire cutting.

[0036] Example 2

[0037] This embodiment provides a method for preparing a comparative test block for eddy current testing of a frame weld based on the first embodiment, comprising the following steps:

[0038] S1, from the prepared and unpainted frame (i.e. Figure 2The test block body is formed by cutting on the structure where the defect is a crack (the corresponding position of the cut sample block in the figure) (when the defect is a crack, the part on the structure where the crack occurs is cut to serve as the raw material for making the physical comparison test block);

[0039] S2, obtain the defect location through on-site frame defect measurement analysis and frame defect failure analysis, and set the first artificial defect 3 and the second artificial defect 4 on the test block body (such as Figure 2 As shown in the figure, the actual measurement and analysis of the cracks found on site at the weld connecting the frame crossbeam tube 2 and the gusset plate 1 shows that the minimum distance between the crack and the weld is at the weld toe edge. Through the failure analysis of the frame crack, the crack source is located at the weld toe edge, which provides a clear plan for the direction, position and size of the design and processing of artificial defects. Two arched artificial defects are processed by wire cutting at the weld toes at the two bends of the U-shaped weld of the physical sample, with the groove depths of 0.5mm and 1mm respectively.

[0040] S3, spray-painting the test block body with the first artificial defect 3 and the second artificial defect 4, and adopting the finished product frame spray-painting process to carry out the painting, so as to form a paint covering layer on the surface of the test block body (in order to achieve complete consistency with the surface state of the actual frame, the comparison test block with artificial defects is spray-painted, and the finished product frame spray-painting process is adopted to carry out the painting, and the thickness of the paint layer is 300 to 500 microns (the same as the thickness of the paint layer of the actual frame), which can ensure the actual defect detection rate and the effectiveness of defect detection).

[0041] The test block body is cut from the real structure, the parent material remains consistent, the welding state is realistically restored, and the welding position is consistent, which can avoid the distortion of the detection signal caused by geometric errors when manually processing the test block; artificial defects are set based on actual measurement analysis, so that the defect distribution of the test block is highly consistent with the actual failure risk, ensuring that the verification conditions are close to the actual detection needs.

[0042] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A comparative test block for eddy current testing of structural welds, characterized by: Including the test block body; The test block body includes a first connecting member and a second connecting member, the first connecting member and the second connecting member are fixed together by welding, and the welding process of the first connecting member and the second connecting member is the same as the welding process of the same position on the frame to be tested; The test block body is provided with a first artificial defect and a second artificial defect; the first artificial defect and the second artificial defect are both determined based on the actual failure analysis of the structure; The outer surface of the test block body is sprayed with a paint covering layer, which is the same as the paint layer on the structure to be tested, and covers the first artificial defect and the second artificial defect.

2. The comparison test block for eddy current testing of structural welds according to claim 1, characterized in that: The first artificial defect is a first arcuate groove, and the second artificial defect is a second arcuate groove; The depth of the first arcuate groove is 0.5 mm, and the depth of the second arcuate groove is 1 mm.

3. The comparison test block for eddy current testing of structural welds according to claim 2, characterized in that: The first arcuate groove and the second arcuate groove are both located at the weld toe position of the corresponding weld.

4. The comparison test block for eddy current testing of structural welds according to claim 2, characterized in that: The first arcuate groove and the second arcuate groove are both formed by wire cutting.

5. A method for making a test block for eddy current testing of a frame weld according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1, cutting the test block body from a prepared and unpainted frame; S2, obtaining defect locations through on-site frame defect measurement analysis and frame defect failure analysis, and setting the first artificial defect and the second artificial defect on the test block body; S3, spray painting the test block body having the first artificial defect and the second artificial defect, using a finished product frame spray painting process to form the paint covering layer on the surface of the test block body.

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