An ultrasonic testing reference block for large-sized angle steel arrays and its usage method

Abstract

The present invention belongs to the technical field of ultrasonic testing, and discloses a large-size angle steel array ultrasonic testing reference block and a using method thereof. The reference block includes a reference block body, and a plurality of artificial defects are prefabricated on the reference block body. The artificial defects include three rectangular grooves and three flat-bottomed holes, and the three rectangular grooves and the three flat-bottomed holes are arranged at both ends of the reference block body. The large-size angle steel array ultrasonic testing reference block of the present invention has the advantages of simple structure, convenient operation, low cost and easy popularization. The reference block is made of a large-size angle steel in-kind used for transmission towers, includes area-type defects and volume-type defects, and all defects in the reference block can be detected by using the array ultrasonic testing technology.

Description

Technical Field

[0001] The present invention belongs to the technical field of ultrasonic testing, and particularly relates to a large-size angle steel array ultrasonic testing reference block and a using method thereof. Background Art

[0002] Large-size angle steel refers to large-size and high-strength angle steel members with a limb width of 220 mm or more and a material of Q420 or more, which have been gradually applied in high-voltage and extra-high-voltage transmission towers. Large-size angle steel has the characteristics of strong load-bearing capacity, clear force transmission, convenient processing, and good integrity. A single Q420 large-size angle steel can, to a certain extent, replace the main materials of Q420 double-ply or quadruple-ply conventional angle steel, thus effectively overcoming the disadvantages of cumbersome construction and poor integrity of multi-ply angle steel, reducing the steel consumption index of the iron tower, significantly reducing the cost of the transmission iron tower, and having good economic efficiency.

[0003] For Q420 large-size angle steel, due to the simultaneous increase in thickness and limb width, the reduction ratio of the slab during hot continuous rolling is low, the grain size of the steel structure is not easily evenly distributed, and the internal macroscopic defects such as pores, shrinkage porosity, and inclusions are not sufficiently broken; at the same time, due to the uneven cooling rate of different parts of the profiled bar after hot rolling, plastic deformation occurs, resulting in residual stress. Therefore, Q420 large-size angle steel poses higher process requirements for steel smelting and hot continuous rolling.

[0004] Due to large stress concentration at the right-angle root of the large-size angle steel, defects such as cracks may occur, which will seriously affect the mechanical properties and service life of the angle steel and pose a safety hazard to the quality of the iron tower. At the same time, after the angle steel profile is installed, it will bear a huge load, and the defect area is prone to expansion, which may cause major safety accidents in severe cases. Therefore, carrying out effective non-destructive testing during the manufacturing and operation processes is of great significance for ensuring the manufacturing quality and application reliability of the angle steel profile.

[0005] In the existing detection technology, there is no specimen block that can meet the requirements of angle steel ultrasonic testing to achieve full detection of internal area-type defects and volume-type defects of the angle steel. Summary of the Invention

[0006] The purpose of the present invention is to provide a large-size angle steel array ultrasonic testing reference block and a using method thereof to achieve full detection of internal area-type defects and volume-type defects of the angle steel.

[0007] To achieve the above purpose, the present invention adopts the following technical solutions:

[0008] In the first aspect, the present invention provides a large-size angle steel array ultrasonic testing reference block, including: a reference block body;

[0009] A plurality of artificial defects are prefabricated on the reference block body;

[0010] The artificial defects include three rectangular grooves and three flat-bottomed holes;

[0011] The three rectangular grooves and three flat-bottomed holes are arranged at both ends of the test block body.

[0012] A further improvement of the present invention is that: the test block body is a cut piece of equilateral L-shaped angle steel;

[0013] The test block body includes a vertical first straight edge and a second straight edge; the connection of the first straight edge and the second straight edge is a right-angle root inner arc.

[0014] A further improvement of the present invention is that: the three rectangular grooves include a first rectangular groove, a second rectangular groove and a third rectangular groove;

[0015] The first rectangular groove is located at the inner corner at one end of the first straight edge, and its length direction is perpendicular to the first straight edge;

[0016] The second rectangular groove is located exactly in the middle of the inner arc inner surface at one end of the test block body, and the inclination direction forms an angle of 45°±20’ with the first straight edge;

[0017] The third rectangular groove is located at one end of the second straight edge, and its length direction is parallel to the second straight edge.

[0018] A further improvement of the present invention is that: the first rectangular groove, the second rectangular groove and the third rectangular groove have the same size, with a length and a depth of 5mm±0.05mm, and a width of 0.5mm±0.05mm; the flatness and perpendicularity of the first rectangular groove with respect to the first straight edge are both less than or equal to 0°20’; the flatness and perpendicularity of the third rectangular groove with respect to the second straight edge are both less than or equal to 0°20’.

[0019] A further improvement of the present invention is that: the distance between the center plane of the first rectangular groove and the edge end of the first straight edge is 100mm; the center plane of the third rectangular groove is equidistant from the upper and lower surfaces of the second straight edge; the distance from the left end of the third rectangular groove to the right edge end of the second straight edge is 100mm.

[0020] A further improvement of the present invention is that: the three flat-bottomed holes include a first flat-bottomed hole, a second flat-bottomed hole and a third flat-bottomed hole;

[0021] The first flat-bottomed hole is located at the other end face of the first straight edge, and its depth direction is perpendicular to the first straight edge;

[0022] The second flat-bottomed hole is located at the middle position of the right-angle root at the other end of the test block body;

[0023] The third flat-bottomed hole is located at the other end face of the second straight edge, and its depth direction is perpendicular to the second straight edge;

[0024] A further improvement of the present invention lies in that: the diameters of the first flat-bottomed hole, the second flat-bottomed hole, and the third flat-bottomed hole are the same, all being 2.0 mm ± 0.03 mm; the depth of the first flat-bottomed hole is 6 mm ± 0.05 mm, the depth of the second flat-bottomed hole is 10 mm ± 0.05 mm, and the depth of the third flat-bottomed hole is 2 mm ± 0.05 mm; the flatness and perpendicularity of the first flat-bottomed hole with respect to the end face are both less than or equal to 0°20'; the flatness and perpendicularity of the second flat-bottomed hole with respect to the end face are both less than or equal to 0°20'; the flatness and perpendicularity of the third flat-bottomed hole with respect to the end face are both less than or equal to 0°20'.

[0025] A further improvement of the present invention lies in that: the distances from the center of the first flat-bottomed hole to the two side surfaces of the first straight edge are equal, and the distance between the center and the end of the first straight edge is 100 mm;

[0026] The second flat-bottomed hole is located at the middle position of the right-angle root, and the distances from the center of the hole to the two outer side surfaces of the right-angle root are both 17.5 mm;

[0027] The distances from the center of the third flat-bottomed hole to the upper and lower surfaces of the second straight edge are equal, and the distance between the center and the end of the second straight edge is 100 mm.

[0028] A further improvement of the present invention lies in that: the radius of the inner arc at the right-angle root of the test block body is 24 mm, and the radius of the inner arc at the end is 11.67 mm; the length of the test block body is 200 mm, the limb width is 250 mm, and the edge thickness is 35 mm.

[0029] In a second aspect, the present invention provides a method for using a large-scale angle steel array ultrasonic detection comparison test block, including the following steps:

[0030] The first step is to prepare an ultrasonic linear array probe, a wedge block, and a flaw detector; apply a coupling agent to the detection surface of the test block body before detection;

[0031] In the second step, without installing the wedge block on the probe, place the probe on the second straight edge surface at the position of the third rectangular groove of the test block body, and perform detection using the reflection method, and record the detection results; using the same method, detect the first flat-bottomed hole, the second flat-bottomed hole, and the third flat-bottomed hole in sequence, and record the detection results;

[0032] In the third step, after the probe and the wedge block are installed, place the working surface of the wedge block on the inner side of the straight edge of the test block body near the end face with the second rectangular groove, move the probe closer to or farther away from the right-angle root, and record the detection results of the second rectangular groove; then place the working surface of the wedge block on the straight edge surface at the position of the first rectangular groove, move the probe closer to or farther away from the first rectangular groove, and record the detection results of the first rectangular groove;

[0033] In the fourth step, actual array ultrasonic testing is carried out on large-sized angle steel. The results of the actual array ultrasonic testing are compared with the results of the array ultrasonic testing of corresponding artificial defects, and the parts where the values are greater than the set threshold are determined to have corresponding defects.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] The large-sized angle steel array ultrasonic testing comparison test block and its usage method provided by the present invention are made of large-sized angle steel in actual use for transmission towers, including area-type defects and volume-type defects, which can cover common defect types; at the same time, the defects are distributed at the right-angle root and the straight edge, representing the common distribution positions of the defects. By using the comparison test block of the present invention for array ultrasonic inspection, area-type defects and volume-type defects at different positions in large-sized angle steel can be detected quickly, accurately and effectively, the purpose of quality inspection of large-sized angle steel is achieved, the integrity of the large-sized angle steel structure is ensured, and the reliability and safety of the transmission tower are also guaranteed.

[0036] The structure of the large-sized angle steel array ultrasonic testing comparison test block and its usage method of the present invention is simple, easy to operate, low in cost and easy to popularize. The present invention can not only be used for the detection of area-type defects and volume-type defects in large-sized angle steel, but also can be popularized and applied to the array ultrasonic testing of R-region defects in other L-shaped or T-shaped structural parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The attached drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0038] Figure 1 is the front view of a large-sized angle steel array ultrasonic testing comparison test block of the present invention;

[0039] Figure 2 is the right view of a large-sized angle steel array ultrasonic testing comparison test block of the present invention;

[0040] Figure 3 is the rear view of a large-sized angle steel array ultrasonic testing comparison test block of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0041] The present invention will be described in detail below with reference to the drawings and in combination with the embodiments. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0042] The following detailed descriptions are all exemplary descriptions, aiming to provide further detailed explanations for the present invention. Unless otherwise specified, all technical terms used in the present invention have the same meanings as commonly understood by those of ordinary skill in the technical field to which the present invention pertains. The terms used in the present invention are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention.

[0043] Please refer to Figures 1 to 3 As shown, the present invention provides a large - size angle steel array ultrasonic testing reference block, including: a reference block body 100 and multiple artificial defects prefabricated on the reference block body.

[0044] Among them: the reference block body 100 is an equilateral large - size L - shaped angle steel cut - piece, made of Q420B high - strength steel and formed by hot rolling. The limb width of the reference block body 100 is 250 mm, the edge thickness is 35 mm, the radius of the inner arc 101 at the right - angle root is 24 mm, the radius of the inner arc 102 at the edge end is 11.67 mm, and the length of the reference block body 100 is 200 mm. The reference block body 100 includes a vertical first straight edge 103 and a second straight edge 104; the connection of the first straight edge 103 and the second straight edge 104 is the inner arc 101 at the right - angle root.

[0045] The multiple artificial defects include 3 rectangular grooves and 3 flat - bottom holes.

[0046] The first rectangular groove 1 is located at the inner - corner of one end of the first straight edge 103, the length direction is perpendicular to the first straight edge 103, and the flatness and perpendicularity with the first straight edge 103 are both less than or equal to 0°20’. The length and depth of the first rectangular groove 1 are both 5 mm ± 0.05 mm, and the width is 0.5 mm ± 0.05 mm;

[0047] The second rectangular groove 2 is located in the middle of the inner - surface of the inner arc 101 at one end of the reference block body 100, and the inclination direction forms an angle of 45° ± 20’ with the first straight edge 103. The length and depth of the second rectangular groove 2 are both 5 mm ± 0.05 mm, and the width is 0.5 mm ± 0.05 mm;

[0048] The third rectangular groove 3 is located at one end of the second straight edge 104, the length direction is parallel to the second straight edge 104, and the flatness and perpendicularity with the second straight edge 104 are both less than or equal to 0°20’. The length and depth of the third rectangular groove 3 are both 5 mm ± 0.05 mm, and the width is 0.5 mm ± 0.05 mm;

[0049] The first flat - bottom hole 4 is located on the end - face of the other end of the first straight edge 103, the depth direction is perpendicular to the first straight edge 103, and the flatness and perpendicularity of the first flat - bottom hole 4 relative to the detection end - face are both less than or equal to 0°20’. The diameter is 2.0 mm ± 0.03 mm, and the depth is 6 mm ± 0.05 mm;

[0050] The second flat-bottomed hole 5 is located at the middle position of the right-angle root at the other end of the test block body 100. The flatness and perpendicularity of the second flat-bottomed hole 5 with respect to the detection end face are both less than or equal to 0°20’. The diameter is 2.0 mm ± 0.03 mm, and the depth is 10 mm ± 0.05 mm;

[0051] The third flat-bottomed hole 6 is located at the end face of the other end of the second straight edge 104. The depth direction is perpendicular to the second straight edge 104. The flatness and perpendicularity of the third flat-bottomed hole 6 with respect to the detection end face are both less than or equal to 0°20’. The diameter is 2.0 mm ± 0.03 mm, and the depth is 2 mm ± 0.05 mm.

[0052] Please refer to Figure 1 As shown, the distance between the central plane of the first rectangular groove 1 and the edge end of the first straight edge 103 is 100 mm; the central plane of the third rectangular groove 3 is equidistant from the upper and lower surfaces of the second straight edge 104; the distance between the left end of the third rectangular groove 3 and the right edge end of the second straight edge 104 is 100 mm.

[0053] Please refer to Figure 3 As shown, the center of the first flat-bottomed hole 4 is equidistant from the two side surfaces of the first straight edge 103, and the distance between the center and the edge end of the first straight edge 103 is 100 mm; the second flat-bottomed hole 5 is located at the middle position of the right-angle root, and the distances between the center of the hole and the two outer side surfaces of the right-angle root are both 17.5 mm; the center of the third flat-bottomed hole 6 is equidistant from the upper and lower surfaces of the second straight edge 104, and the distance between the center and the edge end of the second straight edge 104 is 100 mm.

[0054] In the present invention, the material of the test block body 100 is Q420B high-strength steel. There are no defects such as cracks, folds, scabs, delaminations, and inclusions on the surface of the test block body 100. There are no pits, pockmarks, local scratches, oxide scale press-ins with a depth or height exceeding 0.5 mm and protrusion defects with a height exceeding 1.0 mm on the surface of the test block body 100. The above non-out-of-tolerance defects are allowed to exist, but their depth and height should ensure that the actual size of the test block is within the allowable deviation range. The area of obvious pits and pitted surfaces on the surface of the test block body 100 shall not be greater than 8% of the total area of this surface.

[0055] The present invention provides a method for using a large-size angle steel array ultrasonic detection reference test block, including the following steps:

[0056] In the first step, an array ultrasonic linear array probe with 32 wafers is used. The center frequency of the probe is 10 MHz, the wafer size is 13 mm, the wafer spacing is 0.6 mm, the wafer width is 0.5 mm, the pulse width is 100, the gain is adjusted by 30 dB, and the scanning method is sector scanning. The probe is used in combination with a wedge block for detection, and a flaw detector with 32 channels or more is selected. Apply a coupling agent to the detection surface of the test block before detection;

[0057] In the second step, without installing a wedge block on the probe, place the probe on the surface of the second straight edge 104 at the position of the third rectangular groove 3 of the test block body 100, and perform detection using the reflection method; use the same method to detect the first flat-bottomed hole 4, the second flat-bottomed hole 5, and the third flat-bottomed hole 6 in sequence.

[0058] In the third step, after the probe and the inclined wedge block are installed, place the working surface of the wedge block on the inner side of the straight edge of the test block body 100 near the end face with the second rectangular groove 2, manually move the probe closer to or farther away from the right-angle root, and observe the detection result of the second rectangular groove 2; then place the working surface of the wedge block on the straight edge surface at the position of the first rectangular groove 1, manually move the probe closer to or farther away from the first rectangular groove 1, and observe the detection result of the first rectangular groove 1.

[0059] In the fourth step, analyze the array ultrasonic detection results of each defect; during the subsequent actual detection process, compare the array ultrasonic detection results with the array ultrasonic detection results of the corresponding defects. If it is greater than the set threshold, it can be determined that the corresponding defect has occurred.

[0060] In the fifth step, after the detection is completed, promptly clean the residual coupling agent on the test block body 100, the probe, and the wedge block.

[0061] A large-scale angle steel array ultrasonic detection comparison test block provided by the present invention is made of a large-scale angle steel in-kind used for transmission towers, includes area-type defects and volume-type defects, and can cover common defect types; at the same time, the defects are distributed at the right-angle root and the straight edge, representing the common distribution positions of the defects. Using the comparison test block of the present invention for array ultrasonic inspection can quickly, accurately, and effectively detect area-type defects and volume-type defects at different positions in large-scale angle steel, achieve the purpose of quality inspection of large-scale angle steel, ensure the integrity of the large-scale angle steel structure, and also guarantee the reliability and safety of the transmission tower.

[0062] The structure of the large-scale angle steel array ultrasonic detection comparison test block and its use method of the present invention is simple, easy to operate, low in cost, and easy to promote. The present invention can not only be used for the detection of area-type defects and volume-type defects in large-scale angle steel, but also can be popularized and applied to the array ultrasonic detection of R-region defects in other L-shaped or T-shaped structural parts.

[0063] As is known by technical common sense, the present invention can be implemented by other embodiments without departing from its spiritual essence or essential features. Therefore, the above-disclosed embodiments are illustrative in all aspects and are not the only ones. All changes within the scope of the present invention or within the scope equivalent to the present invention are encompassed by the present invention.

Claims

1. An ultrasonic testing reference block for large-sized angle steel arrays, characterized in that, Comprising: A test block body (100); Multiple artificial defects are prefabricated on the test block body (100); The artificial defects include three rectangular grooves and three flat-bottomed holes; The three rectangular grooves and three flat-bottomed holes are arranged at both ends of the test block body (100); The test block body (100) is an equilateral L-shaped angle steel cut block; The test block body (100) includes a vertical first straight edge (103) and a second straight edge (104); the connection part of the first straight edge (103) and the second straight edge (104) is a right-angle root inner arc (101); The radius of the right-angle root inner arc (101) of the test block body (100) is 24 mm, and the radius of the edge-end inner arc (102) is 11.67 mm; the length of the test block body (100) is 200 mm, the limb width is 250 mm, and the edge thickness is 35 mm; The three rectangular grooves include a first rectangular groove (1), a second rectangular groove (2), and a third rectangular groove (3); The first rectangular groove (1) is located at the inner corner at one end of the first straight edge (103), and the length direction is perpendicular to the first straight edge (103); The second rectangular groove (2) is located in the middle of the inner surface of the inner arc (101) at one end of the test block body (100), and the inclination direction forms an angle of 45° ± 20' with the first straight edge (103); The third rectangular groove (3) is located at one end of the second straight edge (104), and the length direction is parallel to the second straight edge (104); The three flat-bottomed holes include a first flat-bottomed hole (4), a second flat-bottomed hole (5), and a third flat-bottomed hole (6); The first flat-bottomed hole (4) is located at the end face of the other end of the first straight edge (103), and the depth direction is perpendicular to the first straight edge (103); The second flat-bottomed hole (5) is located at the middle position of the right-angle root at the other end of the test block body (100); The third flat-bottomed hole (6) is located at the end face of the other end of the second straight edge (104), and the depth direction is perpendicular to the second straight edge (104).

2. The ultrasonic testing reference block for large-sized angle steel arrays according to claim 1, wherein The first rectangular groove (1), the second rectangular groove (2), and the third rectangular groove (3) have the same dimensions, with a length and depth of 5 mm ± 0.05 mm and a width of 0.5 mm ± 0.05 mm; the flatness and perpendicularity of the first rectangular groove (1) with respect to the first straight edge (103) are both less than or equal to 0°20'; the flatness and perpendicularity of the third rectangular groove (3) with respect to the second straight edge (104) are both less than or equal to 0°20'.

3. A large - specification angle steel array ultrasonic detection reference block according to claim 1, characterized in that, The distance between the center plane of the first rectangular groove (1) and the edge-end of the first straight edge (103) is 100 mm; the center plane of the third rectangular groove (3) is equidistant from the upper and lower surfaces of the second straight edge (104); the left end of the third rectangular groove (3) is 100 mm away from the right edge-end of the second straight edge (104).

4. A large-scale angle steel array ultrasonic testing reference block according to claim 1, characterized in that, The diameters of the first flat-bottomed hole (4), the second flat-bottomed hole (5) and the third flat-bottomed hole (6) are the same, all being 2.0 mm ± 0.03 mm; the depth of the first flat-bottomed hole (4) is 6 mm ± 0.05 mm, the depth of the second flat-bottomed hole (5) is 10 mm ± 0.05 mm, and the depth of the third flat-bottomed hole (6) is 2 mm ± 0.05 mm; the flatness and perpendicularity of the first flat-bottomed hole (4) relative to the end face are both less than or equal to 0°20'; the flatness and perpendicularity of the second flat-bottomed hole (5) relative to the end face are both less than or equal to 0°20'; the flatness and perpendicularity of the third flat-bottomed hole (6) relative to the end face are both less than or equal to 0°20'.

5. A large-scale angle steel array ultrasonic testing reference block according to claim 1, characterized in that, The distances from the center of the first flat-bottomed hole (4) to the two side surfaces of the first straight edge (103) are equal, and the distance between the center and the end of the first straight edge (103) is 100 mm; The second flat-bottomed hole (5) is located at the middle position of the right-angle root, and the distances from the center of the hole to the two outer side surfaces of the right-angle root are both 17.5 mm; The distances from the center of the third flat-bottomed hole (6) to the upper and lower surfaces of the second straight edge (104) are equal, and the distance between the center and the end of the second straight edge (104) is 100 mm.

6. A method for using a large-scale angle steel array ultrasonic testing reference block according to any one of claims 1 to 5, characterized in that, It includes the following steps: The first step is to prepare an ultrasonic linear array probe, a wedge block and a flaw detector; apply a coupling agent to the detection surface of the test block body (100) before detection; In the second step, without installing the wedge block on the probe, place the probe on the surface of the second straight edge (104) at the position of the third rectangular groove (3) of the test block body (100), and perform detection by the reflection method, and record the detection results; use the same method to detect the first flat-bottomed hole (4), the second flat-bottomed hole (5), and the third flat-bottomed hole (6) in sequence, and record the detection results; In the third step, after installing the probe and the wedge block, place the working surface of the wedge block on the inner side of the straight edge of the test block body (100) near the end face with the second rectangular groove (2), move the probe closer to or away from the right-angle root, and record the detection results of the second rectangular groove (2); then place the working surface of the wedge block on the straight edge surface at the position of the first rectangular groove (1), move the probe closer to or away from the first rectangular groove (1), and record the detection results of the first rectangular groove (1); In the fourth step, perform actual array ultrasonic detection on the large-sized angle steel, compare the actual array ultrasonic detection results with the array ultrasonic detection results of the corresponding artificial defects, and identify the parts greater than the set threshold as having the corresponding defects.

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