A comparative test block and method for phased array ultrasonic testing of micro-defects in welded joints

Abstract

A phased array ultrasonic testing comparison block and method for micro-defect detection of weld joints is disclosed. The comparison block comprises a first comparison block, a second comparison block, and a third comparison block used in combination. Each of the first, second, and third comparison blocks is provided with an artificial reflector. The artificial reflector comprises a transverse hole structure and a groove structure disposed on the surface of the comparison block and extending along its thickness. The transverse hole structure comprises a 0.1×6 mm transverse blind hole, a 0.5×6 mm transverse blind hole, a 0.3 mm transverse through hole, and a 0.5 mm transverse through hole. The groove structure comprises specifications of 0.5 mm width, 0.5 mm depth, and 5 mm length, 0.3 mm width, 0.3 mm depth, and 5 mm length, 0.2 mm width, 0.2 mm depth, and 5 mm length, 1 mm width, 2 mm depth, and 5 mm length, 0.5 mm width, 1 mm depth, and 5 mm length. The present invention can effectively quantify micro-defects in weld joints, achieving the purpose of quickly and intuitively assessing defect size.

Description

Technical Field

[0001] The present invention relates to a comparative test block and method for phased array ultrasonic detection of micro-defects in welded joints, belonging to the technical field of welded joint micro-defect detection, and is suitable for detecting early micro-defects and creep holes in high-temperature pipelines of main steam and reheat steam of ultra- and ultra-supercritical generator sets. Background Art

[0002] It is well known that as the material grades used in high-temperature and high-pressure pipelines, headers and other equipment of super and ultra-supercritical power generation units become higher and higher, the safety margin is increasingly compressed while meeting the design requirements. The harmfulness of internal defects in the welded joints of high-temperature and high-pressure equipment has increased compared with before, and traditional defect assessment methods are difficult to meet the requirements of accurate defect assessment.

[0003] At present, the main steam and reheat steam high-temperature pipelines of ultra-supercritical and ultra-supercritical power generation units are mostly made of P91 / P92 steel. In the early stage, many tiny crack defects appeared in the welded joints. Moreover, as the operation time of the P92 steel welded joints increases, creep holes will appear in the fine-grained area of the heat-affected zone, and gradually grow, connect, and expand into type IV cracks. When ultrasonic testing or phased array ultrasonic testing is used to detect internal defects in welded joints, the equivalent comparison method is employed. In power systems, the Φ2×40 and Φ2×60 through-holes specified in the NB / T 47013.3 "Ultrasonic Testing for Nondestructive Testing of Pressure Equipment," the Φ3×40 through-hole specified in the DL / T 820 "Technical Specification for Ultrasonic Testing of Pipeline Welded Joints - Part 2: Type A Pulse-Echo Method," and the Φ2×30 through-hole specified in the DL / T 1718 "Technical Specification for Phased Array Ultrasonic Testing of Welded Joints in Thermal Power Plants" are commonly used as reference reflectors. DAC or TCG curves are then plotted, and the detection sensitivity is then reduced by a certain number of dB. The equivalent difference between the defect under test and the reference through-hole is used as the evaluation criterion. Because micro-defects and creep voids in P91 / P92 welded joints are inherently small, the ultrasonic echo height of these defects often falls below the detection assessment threshold, making them non-recordable defects. Furthermore, the size of micro-defects within welded joints is much smaller than the aperture of the standard test block, making comparisons based on equivalent amplitudes highly inaccurate and unintuitive. Summary of the Invention

[0004] In order to overcome the above-mentioned shortcomings of the related art, the present invention provides a phased array ultrasonic detection comparison test block and method for micro-defects in welded joints, which can effectively quantify micro-defects in welded joints, achieve the purpose of quickly and intuitively evaluating the size of defects, and at the same time have high accuracy and reliability.

[0005] A technical solution adopted by the present invention to solve its technical problem is:

[0006] A comparative test block for phased array ultrasonic testing of micro-defects in welded joints, comprising a first comparative test block, a second comparative test block, and a third comparative test block used in combination, wherein the first comparative test block, the second comparative test block, and the third comparative test block are each independently provided with an artificial reflector, wherein the artificial reflector comprises a transverse hole structure and a groove structure provided on a surface of the comparative test block and extending along a thickness direction thereof;

[0007] The transverse hole structure includes Φ0.1×6mm transverse blind holes, Φ0.5×6mm transverse blind holes, Φ0.3 transverse through holes and Φ0.5 transverse through holes;

[0008] The groove structure includes transverse grooves with specifications of width 0.5×depth 0.5×length 5mm, transverse grooves with width 0.3×depth 0.3×length 5mm, transverse grooves with width 0.2×depth 0.2×length 5mm, transverse grooves with width 1×depth 2×length 5mm, transverse grooves with width 0.5×depth 1×length 5mm and transverse grooves with width 0.2×depth 1×length 5mm.

[0009] Optionally, the first comparison test block, the second comparison test block and the third comparison test block are all solid rectangular structures, and the materials of the three are the same as the material of the inspected pipeline.

[0010] Optionally, the specifications of the rectangular solid structure are 400 mm in length × 30 mm in width × 45 mm in height, and the material is P91 / P92 steel.

[0011] Optionally, the artificial reflector I provided on the first comparison test block includes a group of Φ0.1×6 mm transverse blind holes I arranged vertically and equidistantly at one end of the first working surface of the first comparison test block, a group of Φ0.1×6 mm transverse blind holes II arranged obliquely and equidistantly at the upper portion of the other end of the first working surface, and a group of Φ0.1×6 mm transverse blind holes III arranged transversely and equidistantly at the lower portion of the other end of the first working surface;

[0012] and a plurality of transverse grooves I of different specifications arranged equidistantly along the length direction on the upper and lower surfaces of one end of the second working surface of the first comparison test block, and a group of arc-shaped transverse blind holes of Φ0.5×6 arranged at the other end of the second working surface;

[0013] The first working surface and the second working surface are arranged opposite to each other in space.

[0014] Optionally, the number of the Φ0.1×6mm transverse blind holes I is 8, the hole centers are vertically arranged 50mm away from the end surface, the distance between adjacent hole centers is 5mm, and the upper and lower holes are 5mm away from the adjacent surfaces respectively;

[0015] The number of the Φ0.1×6mm transverse blind holes II is 7, and the distances from the center of each hole to the upper surface and the side end surface are the same, namely 5mm, 10mm, 15mm, 20mm, 25mm, 30mm and 35mm respectively;

[0016] The number of the Φ0.1×6mm transverse blind holes III is 10, the hole centers are horizontally arranged 50mm away from the lower surface, the distance between adjacent hole centers is 5mm, and the center of the outermost hole is 5mm away from the end surface on the b side;

[0017] The transverse grooves I include three first transverse grooves I located at the upper part, with specifications of: width 0.5 × depth 0.5 × length 5mm, width 0.3 × depth 0.3 × length 5mm, width 0.2 × depth 0.2 × length 5mm, the groove center distance is 5mm, and the outermost groove is 40mm from the end surface;

[0018] The transverse groove I also includes three second transverse grooves I located at the bottom, with specifications of: width 1×depth 2×length 5mm, width 0.5×depth 1×length 5mm, width 0.2×depth 1×length 5mm, and center distance of each is 10mm. The outermost groove is 30mm away from the end surface.

[0019] There are 15 Φ0.5×6 transverse blind holes, which are distributed along a circumference with a radius of 45 mm, with the position 50 mm from the upper surface to the end face as the center. The uppermost hole is 5 mm from the upper surface, the center interval between each two holes is 5°, and the center interval between the two holes at the bottom is 3°.

[0020] Optionally, the artificial reflector II set on the second comparison test block includes a group of Φ0.3 transverse through holes I arranged vertically and equidistantly, which are arranged at one end of the second comparison test block and pass through two relative working surfaces; a group of Φ0.3 transverse through holes II arranged obliquely and equidistantly, which are arranged at the upper part of the other end of the second comparison test block and pass through two relative working surfaces; and a group of Φ0.3 transverse through holes III arranged laterally and equidistantly, which are arranged at the lower part of the other end of the second comparison test block and pass through two relative working surfaces.

[0021] Optionally, the number of the Φ0.3 transverse through holes I is 8, the center of the hole is 50 mm away from the end surface, the center spacing of adjacent holes is 5 mm, and the upper and lower holes are 5 mm away from the adjacent surface respectively;

[0022] The number of the Φ0.3 transverse through holes II is 7, and the distances from the center of each hole to the upper surface and the side end surface are the same, namely 5mm, 10mm, 15mm, 20mm, 25mm, 30mm and 35mm respectively;

[0023] The number of the Φ0.3 transverse through holes III is 10, the hole centers are horizontally arranged at a distance of 50 mm from the lower surface, the distance between adjacent hole centers is 5 mm, and the distance between the center of the outermost hole and the end surface on the b side is 5 mm.

[0024] Optionally, the artificial reflector III set on the third comparison test block includes a group of Φ0.5 transverse through holes I arranged vertically and equidistantly, which are arranged at one end of the third comparison test block and pass through two opposite working surfaces; a group of Φ0.5 transverse through holes II arranged obliquely and equidistantly, which are arranged at the upper part of the other end of the second comparison test block and pass through two opposite working surfaces; and a group of Φ0.5 transverse through holes III arranged laterally and equidistantly, which are arranged at the lower part of the other end of the second comparison test block and pass through two opposite working surfaces.

[0025] Optionally, the number of the Φ0.5 transverse through holes I is 8, the center of the hole is 50 mm away from the end surface, the center spacing of adjacent holes is 5 mm, and the upper and lower holes are 5 mm away from the adjacent surface respectively;

[0026] The number of the Φ0.5 transverse through holes II is 7, and the distances from the center of each hole to the upper surface and the side end surface are the same, namely 5mm, 10mm, 15mm, 20mm, 25mm, 30mm and 35mm respectively;

[0027] The number of the Φ0.5 transverse through holes III is 10, the hole centers are horizontally arranged at a distance of 50 mm from the lower surface, the distance between adjacent hole centers is 5 mm, and the distance between the center of the outermost hole and the end surface on the side b is 5 mm.

[0028] Another technical solution adopted by the present invention to solve its technical problem is:

[0029] A phased array ultrasonic detection method for micro-defects in welded joints comprises the following steps:

[0030] 1) According to the thickness of the workpiece being tested, adjust the sensitivity using a conventional through-hole comparison test block in accordance with the requirements of the implementation standards NB / T 47013, DL / T 820 or DL / T1718, and draw a DAC or TCG curve;

[0031] 2) placing the phased array probe on the upper or lower side of the first comparison test block, the second comparison test block, and the third comparison test block, respectively, finding the artificial reflector corresponding to the same depth as when drawing the DAC or TCG curve in step 1), and recording the echo equivalent values of the Φ0.1×6mm transverse blind hole, Φ0.5×6mm transverse blind hole, Φ0.3 transverse through hole, and Φ0.5 transverse through hole at the same depth, respectively. At the same time, record the echo equivalent values of different grooves at different depths, compare them with the detection sensitivity value set with the conventional through hole comparison test block, and draw a line graph of the difference in echo equivalents of different apertures at the same depth;

[0032] 3) During actual detection, a comparative analysis is performed based on the echo equivalent difference line graph and the thermal image morphology, color and defect reflection display of reference reflectors at different depths and apertures.

[0033] Compared with related technologies, the present invention provides a comparison test block and method for phased array ultrasonic detection of micro-defects in welded joints. By designing a first comparison test block, a second comparison test block, and a third comparison test block that are close to an artificial reflector in terms of micro-defect morphology and equivalent size, the artificial reflector is scanned and a DAC curve (distance amplitude curve) or TCG curve (depth compensation curve) is drawn for detection. The baseline of the drawn DAC curve or TCG curve is closer to the equivalent amplitude of the actual micro-defect. This is used as a benchmark for equivalent comparison with micro-defects of various sizes found during detection, with high accuracy and reliability, and can effectively quantify micro-defects. At the same time, during phased array detection, the thermal view color display can be set according to the echo equivalent of the designed reflector. The defect display view in the phased array detection data acquisition view can be compared with the thermal view color of the designed reflector to achieve the purpose of quickly and intuitively evaluating the defect size. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The present invention will be further described below with reference to the accompanying drawings and examples.

[0035] Figure 1 It is a front view of a first comparison test block in one embodiment of the present invention.

[0036] Figure 2 It is a rear view of the first comparison test block in one embodiment of the present invention.

[0037] Figure 3 It is a top view of a first comparison test block in one embodiment of the present invention, and is a structural diagram in a perspective state.

[0038] Figure 4 It is a front view of a second comparison test block in one embodiment of the present invention.

[0039] Figure 5 It is a top view of the second comparison test block in one embodiment of the present invention, and is a structural diagram in a perspective state.

[0040] Figure 6 It is a front view of the third comparison test block in one embodiment of the present invention.

[0041] Figure 7 It is a top view of the third comparison test block in one embodiment of the present invention, and is a structural diagram in a perspective state.

[0042] Description of reference numerals in the figures:

[0043] 1-First comparison block; 11-Artificial reflector I; 111-Φ0.1×6mm transverse blind hole I; 112-Φ0.1×6mm transverse blind hole II; 113-Φ0.1×6mm transverse blind hole III; 114-Transverse groove I; 1141-First transverse groove I; 1142-Second transverse groove I; 115-Φ0.5×6 transverse blind hole;

[0044] 2-second comparison test block; 21-artificial reflector II; 211-Φ0.3 transverse through hole I; 212-Φ0.3 transverse through hole II; 213-Φ0.3 transverse through hole III;

[0045] 3-the third comparison test block; 31-artificial reflector III; 311-Φ0.5 transverse through hole I; 312-Φ0.5 transverse through hole II; 313-Φ0.5 transverse through hole III. DETAILED DESCRIPTION

[0046] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0047] Figures 1 to 7 A schematic structural diagram of a preferred embodiment of the present invention is shown. A comparative test block for phased array ultrasonic testing of micro-defects in welded joints is shown, comprising a first comparative test block 1, a second comparative test block 2, and a third comparative test block 3 used in combination. Each of the first comparative test block 1, the second comparative test block 2, and the third comparative test block 3 is individually provided with an artificial reflector. The artificial reflector comprises a transverse hole structure and a groove structure provided on the surface of the comparative test block and extending along the thickness direction thereof.

[0048] The transverse hole structure includes Φ0.1×6mm transverse blind holes, Φ0.5×6mm transverse blind holes, Φ0.3 transverse through holes and Φ0.5 transverse through holes;

[0049] The groove structure includes transverse grooves with specifications of width 0.5×depth 0.5×length 5mm, transverse grooves with width 0.3×depth 0.3×length 5mm, transverse grooves with width 0.2×depth 0.2×length 5mm, transverse grooves with width 1×depth 2×length 5mm, transverse grooves with width 0.5×depth 1×length 5mm and transverse grooves with width 0.2×depth 1×length 5mm.

[0050] To address the difficulty in accurately quantifying and recording micro-defects in welded joints, this embodiment designs an artificial reflector that more closely resembles the echo reflection mechanism of micro-defects within welded joints. This is used for calibration of detection sensitivity, comparative analysis of defect echoes, and defect morphology when using phased array ultrasonic testing of welded joints. Specifically, the Φ0.1×6mm transverse blind hole in the transverse hole structure of the artificial reflector serves as a comparison for the detectable extreme value of micro-defects within the welded joint, and the Φ0.5×6mm transverse blind hole serves as a comparison reflector for relatively small micro-defects. Furthermore, the echo equivalents of both the Φ0.1×6mm transverse blind hole and the Φ0.5×6mm transverse blind hole reflectors are compared with the Φ1×6mm transverse blind hole reference reflector of the CSK-ⅢA test block specified in the NB / T47013.3 standard. The echo equivalent levels of Φ0.3 and Φ0.5 transverse through-holes are similar to those of micro-defects, making them suitable as reference reflectors for plotting DAC or TCG curves. They can also be compared with the Φ2×30 through-hole reference reflector in the PRB series test blocks specified in the DL / T 1718 standard. The groove structure is designed as a reference reflector with a reflection mechanism similar to that of micro-crack-like defects, enabling equivalent amplitude comparisons for micro-cracks of different sizes.

[0051] In a specific implementation of this embodiment, in terms of specifications, the first comparison test block 1, the second comparison test block 2, and the third comparison test block 3 are all solid rectangular structures. In a further specific implementation of this embodiment, the specifications of the solid rectangular structure are 400mm long × 30mm wide × 45mm high, where the width is designed to be 30mm to meet the acoustic beam width range of the phased array probe, and the block height is designed to be 45mm. When the phased array detection uses only the primary wave for curve adjustment, it can meet the detection requirements of workpieces with a wall thickness of 40mm. When the primary wave and the secondary wave are used simultaneously for curve adjustment, it can meet the detection requirements of workpieces with a wall thickness of 85mm. The length is designed to be 400mm to meet the probe movement distance when using the secondary wave for scanning artificial reflectors.

[0052] In terms of material, the first, second, and third comparison test blocks 1, 2, and 3 are made of the same material as the inspected pipe. Furthermore, the acoustic performance of the first, second, and third comparison test blocks 1, 2, and 3 should be the same as or similar to that of the inspected workpiece. In a further embodiment of this embodiment, P91 / P92 steel is used as the material.

[0053] Reference Figure 1-3In a further optional implementation of this embodiment, the artificial reflector I11 provided on the first comparison test block 1 includes a group of Φ0.1×6 mm transverse blind holes I111 arranged vertically and equidistantly at one end of the first working surface of the first comparison test block 1, a group of Φ0.1×6 mm transverse blind holes II112 arranged obliquely and equidistantly at the upper portion of the other end of the first working surface, and a group of Φ0.1×6 mm transverse blind holes III113 arranged transversely and equidistantly at the lower portion of the other end of the first working surface;

[0054] and a plurality of transverse grooves I 114 of different specifications arranged equidistantly along the length direction on the upper and lower surfaces of one end of the second working surface of the first comparison test block 1, and a group of arc-shaped transverse blind holes 115 of Φ0.5×6 arranged at the other end of the second working surface;

[0055] The first working surface and the second working surface are arranged relative to each other in space. In this embodiment, the first working surface and the second working surface are two areas in which the first comparison test block 1 is divided along the width direction, marked as surface A and surface B.

[0056] As one of the further optional implementations of this embodiment, the number of the Φ0.1×6mm transverse blind holes I111 is 8, the hole centers are vertically arranged 50mm away from the end surface, the distance between adjacent hole centers is 5mm, and the upper and lower holes are 5mm away from the adjacent surfaces respectively;

[0057] The number of the Φ0.1×6mm transverse blind holes II 112 is 7, and the distances from the center of each hole to the upper surface and the side end surface are the same, namely 5mm, 10mm, 15mm, 20mm, 25mm, 30mm and 35mm respectively;

[0058] The number of the Φ0.1×6mm transverse blind holes III 113 is 10, the hole centers are 50mm away from the lower surface and arranged horizontally, the distance between adjacent hole centers is 5mm, and the distance between the center of the outermost hole and the end surface on the side b is 5mm;

[0059] The transverse grooves I114 include three first transverse grooves I1141 located at the upper portion, with specifications of: width 0.5 × depth 0.5 × length 5 mm, width 0.3 × depth 0.3 × length 5 mm, width 0.2 × depth 0.2 × length 5 mm, and a groove center distance of 5 mm. The outermost groove is 40 mm from the end surface.

[0060] The transverse groove I 114 also includes three second transverse grooves I 1142 located at the bottom, with specifications of: width 1×depth 2×length 5mm, width 0.5×depth 1×length 5mm, width 0.2×depth 1×length 5mm, and center distance of each is 10mm. The outermost groove is 30mm away from the end surface.

[0061] The number of the Φ0.5×6 transverse blind holes 115 is 15, which are distributed along a circumference of a radius of 45 mm with the position 50 mm from the upper surface to the end face as the center of the circle. The uppermost hole is 5 mm from the upper surface, the center interval between each two holes is 5°, and the center interval between the two holes at the bottom is 3°.

[0062] In the illustrated embodiment, the above-mentioned Φ0.1×6mm transverse blind hole I111 is designed on the a-side of surface A, the Φ0.1×6mm transverse blind hole II112 is designed on the b-side of surface A, the Φ0.1×6mm transverse blind hole III113 is designed on the lower part of the b-side of surface A, the transverse groove I114 is designed on the upper surface of the a-side of surface B and the lower surface of the a-side of surface B, and the Φ0.5×6 transverse blind hole 115 is designed on the b-side of surface B.

[0063] Reference Figure 4-5 In a further optional implementation of this embodiment, the artificial reflector II 21 provided on the second comparison test block 2 includes a set of 0.3 mm lateral through holes I 211 arranged vertically and equidistantly, extending through two opposing working surfaces at one end of the second comparison test block 2; a set of 0.3 mm lateral through holes II 212 arranged diagonally and equidistantly, extending through the two opposing working surfaces at the upper portion of the other end of the second comparison test block 2; and a set of 0.3 mm lateral through holes III 213 arranged laterally and equidistantly, extending through the two opposing working surfaces at the lower portion of the other end of the second comparison test block 2. In the illustrated embodiment, the two opposing working surfaces are defined as two regions divided along the width of the second comparison test block 2.

[0064] As one of the further optional implementations of this embodiment, the number of the Φ0.3 transverse through holes I 211 is 8, the hole center is 50 mm away from the end surface, the distance between adjacent hole centers is 5 mm, and the upper and lower holes are 5 mm away from the adjacent surface respectively;

[0065] The number of the Φ0.3 transverse through holes II 212 is 7, and the distances from the center of each hole to the upper surface and the side end surface are the same, namely 5mm, 10mm, 15mm, 20mm, 25mm, 30mm and 35mm respectively;

[0066] The number of the Φ0.3 transverse through holes III 213 is 10, the hole centers are horizontally arranged at a distance of 50 mm from the lower surface, the distance between adjacent hole centers is 5 mm, and the distance between the center of the outermost hole and the end surface on the b side is 5 mm.

[0067] In the illustrated embodiment, the Φ0.3 transverse through hole I 211 is designed on the a side of the working surface, the Φ0.3 transverse through hole II 212 is designed on the upper part of the b side of the working surface, and the Φ0.3 transverse through hole III 213 is designed on the lower part of the b side of the working surface.

[0068] Reference Figure 6-7In a further optional implementation of this embodiment, the artificial reflector III 31 provided on the third comparison test block 3 includes a set of 0.5 mm lateral through holes I 311 arranged vertically and equidistantly, extending through two opposing working surfaces at one end of the third comparison test block 3; a set of 0.5 mm lateral through holes II 312 arranged obliquely and equidistantly, extending through the two opposing working surfaces at the upper portion of the other end of the second comparison test block 2; and a set of 0.5 mm lateral through holes III 313 arranged laterally and equidistantly, extending through the two opposing working surfaces at the lower portion of the other end of the second comparison test block 2. In the illustrated embodiment, the two opposing working surfaces are defined as two regions divided along the width of the third comparison test block 3.

[0069] As one of the further optional implementations of this embodiment, the number of the Φ0.5 transverse through holes I311 is 8, the hole center is 50 mm away from the end surface, the distance between adjacent hole centers is 5 mm, and the upper and lower holes are 5 mm away from the adjacent surface respectively;

[0070] The number of the Φ0.5 transverse through holes II 312 is 7, and the distances from the center of each hole to the upper surface and the side end surface are the same, namely 5mm, 10mm, 15mm, 20mm, 25mm, 30mm and 35mm respectively;

[0071] The number of the Φ0.5 transverse through holes III 313 is 10, the hole centers are horizontally arranged at a distance of 50 mm from the lower surface, the distance between adjacent hole centers is 5 mm, and the distance between the center of the outermost hole and the end surface on the side b is 5 mm.

[0072] In the illustrated embodiment, the Φ0.5 transverse through hole I 311 is designed on the a side of the working surface, the Φ0.5 transverse through hole II 312 is designed on the upper part of the b side of the working surface, and the Φ0.5 transverse through hole III 313 is designed on the lower part of the b side of the working surface.

[0073] Method for using a comparison test block for phased array ultrasonic testing of weld joint micro-defects in an embodiment of the present invention

[0074] 1. How to use the horizontal hole structure in the comparison test block

[0075] 1) When using the phased array conventional focusing method for testing, a DAC or TCG curve can be drawn based on the vertically arranged Φ0.1×6mm transverse blind holes on side a of surface A of the first comparison test block 1. The baseline of the curve is the equivalent Φ0.1×6mm transverse blind hole. When using the phased array full focusing method for testing, the instrument settings can be based on the vertically arranged Φ0.1×6mm transverse blind holes on side a of surface A and the diagonally and horizontally arranged Φ0.1×6mm transverse blind holes on side b of surface A. Since DAC or TCG curves do not need to be drawn during full focusing testing, the vertically arranged, diagonally arranged, and horizontally arranged transverse blind holes serve as the equivalent settings for acoustic field spatial balance calibration and testing during full focusing law adjustment.

[0076] 2) When using the phased array conventional focusing method, a DAC or TCG curve can be drawn based on the vertically arranged Φ0.3 transverse through-holes on the second comparison test block 2a, with the baseline of the curve being the equivalent Φ0.3 transverse through-hole. When using the phased array full focusing method, instrument settings can be made based on the vertically arranged Φ0.3 transverse through-holes on side a of surface A and the obliquely and horizontally arranged Φ0.3 transverse through-holes on side b of surface A.

[0077] 3) When using the phased array conventional focusing method, a DAC or TCG curve can be drawn based on the vertically arranged Φ0.5 transverse through-holes on the side of the third comparison test block 3a, with the baseline of the curve being the equivalent Φ0.5 transverse through-hole. When using the phased array full focusing method, instrument settings can be made based on the vertically arranged Φ0.5 transverse through-holes on side a of surface A and the obliquely arranged and horizontally arranged Φ0.5 transverse through-holes on side b of surface A.

[0078] 4) When using the phased array full focusing method for testing, the instrument settings can be made based on the Φ0.5×6mm transverse blind holes arranged in a semicircle on the b side of the B surface of the first comparison test block 1. The equivalent amplitude of the Φ0.5×6mm transverse blind holes is the benchmark detection equivalent.

[0079] 5) The obliquely arranged horizontal holes and horizontally arranged horizontal holes in the first comparison test block 1, the second comparison test block 2, and the third comparison test block 3, as well as the semicircular arrangement of the horizontal holes in the first comparison test block 1, can also be used for comparative analysis of the angular resolution and horizontal resolution when adjusting the phased array instrument.

[0080] 2. Comparison of the use of groove structure in test blocks

[0081] When using the phased array ordinary focusing method for detection, grooves of different sizes on the first comparison test block 1 are tested. Method 1 can use primary and secondary waves to calibrate grooves of the same size respectively; Method 2 can calibrate the reflection equivalent of grooves of different sizes, draw the groove equivalent horizontal line, and multiple equivalent horizontal lines form a comparison diagram of the echo amplitude of the groove and small crack defects.

[0082] When using the phased array full focusing method for detection, grooves of different sizes on the first comparison test block 1 are tested, the reflection equivalents of the grooves of different sizes are calibrated, and the groove equivalent horizontal lines are drawn. Multiple equivalent horizontal lines form a comparison diagram of the echo amplitudes of the grooves and tiny crack defects.

[0083] The present invention also provides a phased array ultrasonic detection method for micro-defects in welded joints, comprising the following steps:

[0084] 1) Set the detection sensitivity: According to the thickness of the workpiece to be inspected, adjust the sensitivity using a conventional through-hole comparison test block in accordance with the requirements of the implementation standards NB / T 47013, DL / T 820 or DL / T 1718, and draw a DAC or TCG curve;

[0085] 2) Comparison of detection sensitivity differences: Place the phased array probe on the upper or lower side of the first comparison test block 1, the second comparison test block 2, and the third comparison test block 3, respectively, and find the artificial reflector corresponding to the same depth as when drawing the DAC or TCG curve in step 1), and record the echo equivalent values of the Φ0.1×6mm transverse blind hole, Φ0.5×6mm transverse blind hole, Φ0.3 transverse through hole, and Φ0.5 transverse through hole at the same depth, respectively. At the same time, record the echo equivalent values of different grooves at different depths, compare them with the detection sensitivity values set with the conventional through hole comparison test block, and draw a line graph of the difference in echo equivalents of different apertures at the same depth;

[0086] 3) During actual detection, a comparative analysis is performed based on the echo equivalent difference line graph and the thermal image morphology, color and defect reflection display of reference reflectors at different depths and apertures.

[0087] The present invention provides a phased array ultrasonic detection method for micro-defects in welded joints based on phased array ultrasonic detection technology, which is a multi-beam scanning imaging technology. The ultrasonic detection probe array unit excites ultrasound with a controllable phase under the excitation of the transmitting circuit, and focuses the ultrasonic beam at a determined sound field. Compared with conventional ultrasonic detection, phased array detection has accurate defect positioning, high detection sensitivity, and intuitive detection results. When using phased array ultrasonic detection technology to detect and monitor micro-defects inside welded joints, the views of the data collected by the phased array detection are usually presented in A, B, C, and S scans, where the B, C, and S scans are all in the form of thermal views, and the A scan is a conventional ultrasonic waveform. When analyzing the data, it is necessary to use a pointer to mark the defect display, and then judge the equivalent size of the defect based on the echo amplitude of the A scan. It is difficult to intuitively evaluate or judge the defect size and defect changes by scanning the defect thermal view morphology on the image.

[0088] The detection application process of the phased array ultrasonic detection method for micro-defects in welded joints of the present invention is as follows:

[0089] 1. Phased Array Detection Grouping Settings

[0090] When performing phased array ultrasonic testing on welded joints, the first step is to set up the test settings based on factors such as the thickness of the workpiece being tested and the test location. These settings include the number of excitation elements, scanning angle, focus depth, and TCG curves or equivalent sensitivity of the test sound field. These curves or equivalent sensitivity are generated in accordance with the standards NB / T 47013, DL / T 820, or DL / T1718, and this test setting is named Group 1.

[0091] Without replacing the detection probe and keeping the settings such as the number of excitation chips, scanning angle, and focus depth unchanged, add probe scanning group 2 and use step 1) of the above-mentioned method for using the horizontal hole structure to create a TCG curve or formulate the detection sound field equivalent sensitivity.

[0092] By analogy, add probe scanning group 3, and produce a TCG curve or formulate the equivalent sensitivity of the detection sound field through step 2) of the method for using the above-mentioned horizontal hole structure; add probe scanning group 4, and produce a TCG curve or formulate the equivalent sensitivity of the detection sound field through step 3) of the method for using the above-mentioned horizontal hole structure; add probe scanning group 5, and produce a TCG curve or formulate the equivalent sensitivity of the detection sound field through step 4) of the method for using the above-mentioned horizontal hole structure; add probe scanning group 6, and produce a TCG curve or formulate the equivalent sensitivity of the detection sound field through the method for using the above-mentioned groove structure.

[0093] The above-mentioned probe scanning group and the corresponding artificial reflectors of the test blocks can be set separately or used in combination. That is, the total probe scanning group can include:

[0094] 1) Group 1, Group 2;

[0095] 2) Group 1 and Group 3;

[0096] 3) Group 1, Group 2, Group 3;

[0097] 4) Group 1, Group 2, Group 3, Group 4;

[0098] 5) Group 1, Group 2, Group 4, Group 6;

[0099] 6) Group 1, Group 2, Group 3, Group 4, Group 5, Group 6;

[0100] …

[0101] 2. Data Collection

[0102] The welding joints are inspected using pre-set settings. The inspection process does not need to be repeated multiple times. The inspection data is saved after one scan and can be analyzed directly on the instrument or imported into a computer for analysis using dedicated analysis software.

[0103] 3. Data Analysis

[0104] Recall the preset group 1, group 2, group 3, etc. to collect data information respectively, compare the thermal images under different artificial reflector sensitivities with the collected defect thermal images in terms of morphology and color differences, and accurately, intuitively and effectively calculate and analyze the equivalent size of micro-defects in the detection data.

[0105] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modifications and equivalent changes made to the above embodiment based on the technical essence of the present invention fall within the scope of protection of the present invention.

Claims

1. A comparative test block for phased array ultrasonic testing of weld joint micro-defects, characterized by: The method comprises a first comparative test block, a second comparative test block and a third comparative test block used in combination, wherein the first comparative test block, the second comparative test block and the third comparative test block are each provided with an artificial reflector, wherein the artificial reflector comprises a transverse hole structure and a groove structure provided on the surface of the comparative test block and extending along the thickness direction thereof; The transverse hole structure includes Φ0.1×6mm transverse blind holes, Φ0.5×6mm transverse blind holes, Φ0.3 transverse through holes and Φ0.5 transverse through holes; The groove structure includes transverse grooves with specifications of width 0.5×depth 0.5×length 5mm, transverse grooves with width 0.3×depth 0.3×length 5mm, transverse grooves with width 0.2×depth 0.2×length 5mm, transverse grooves with width 1×depth 2×length 5mm, transverse grooves with width 0.5×depth 1×length 5mm and transverse grooves with width 0.2×depth 1×length 5mm; The artificial reflector I provided on the first comparison test block includes a group of Φ0.1×6mm transverse blind holes I arranged vertically and equidistantly at one end of the first working surface of the first comparison test block, a group of Φ0.1×6mm transverse blind holes II arranged obliquely and equidistantly at the upper portion of the other end of the first working surface, and a group of Φ0.1×6mm transverse blind holes III arranged transversely and equidistantly at the lower portion of the other end of the first working surface; and a plurality of transverse grooves I of different specifications arranged equidistantly along the length direction, respectively provided on the upper and lower surfaces of one end of the second working surface of the first comparison test block, and a group of arc-shaped transverse blind holes of Φ0.5×6 provided at the other end of the second working surface; the first working surface and the second working surface are arranged relative to each other in space; The artificial reflector II provided on the second comparison test block includes a group of Φ0.3 transverse through holes I arranged vertically and equidistantly at one end of the second comparison test block and penetrating the two opposite working surfaces, a group of Φ0.3 transverse through holes II arranged obliquely and equidistantly at the upper portion of the other end of the second comparison test block and penetrating the two opposite working surfaces, and a group of Φ0.3 transverse through holes III arranged laterally and equidistantly at the lower portion of the other end of the second comparison test block and penetrating the two opposite working surfaces; The artificial reflector III set on the third comparison test block includes a group of Φ0.5 horizontal through holes I arranged vertically and equidistantly, which are arranged at one end of the third comparison test block and pass through two opposite working surfaces; a group of Φ0.5 horizontal through holes II arranged obliquely and equidistantly, which are arranged at the upper part of the other end of the second comparison test block and pass through the two opposite working surfaces; and a group of Φ0.5 horizontal through holes III arranged laterally and equidistantly, which are arranged at the lower part of the other end of the second comparison test block and pass through the two opposite working surfaces.

2. The comparative test block for phased array ultrasonic testing of weld joint micro-defects according to claim 1 is characterized by: The first comparison test block, the second comparison test block and the third comparison test block are all solid rectangular structures, and the materials of the three are the same as the material of the inspected pipeline.

3. The comparative test block for phased array ultrasonic testing of weld joint micro-defects according to claim 2 is characterized by: The specifications of the rectangular solid structure are 400 mm in length × 30 mm in width × 45 mm in height, and the material used is P91 / P92 steel.

4. The comparative test block for phased array ultrasonic testing of weld joint micro-defects according to claim 3 is characterized by: The number of the Φ0.1×6mm transverse blind holes I is 8, the hole centers are 50mm away from the end surface and arranged vertically, the distance between adjacent hole centers is 5mm, and the upper and lower holes are 5mm away from the adjacent surfaces respectively; The number of the Φ0.1×6mm transverse blind holes II is 7, and the distances from the center of each hole to the upper surface and the side end surface are the same, namely 5mm, 10mm, 15mm, 20mm, 25mm, 30mm and 35mm respectively; The number of the Φ0.1×6mm transverse blind holes III is 10, the hole centers are horizontally arranged 50mm away from the lower surface, the distance between adjacent hole centers is 5mm, and the center of the outermost hole is 5mm away from the end surface on the b side; The transverse grooves I include three first transverse grooves I located at the upper part, with specifications of: width 0.5 × depth 0.5 × length 5mm, width 0.3 × depth 0.3 × length 5mm, width 0.2 × depth 0.2 × length 5mm, the groove center distance is 5mm, and the outermost groove is 40mm from the end surface; The transverse groove I also includes three second transverse grooves I located at the bottom, with specifications of: width 1×depth 2×length 5mm, width 0.5×depth 1×length 5mm, width 0.2×depth 1×length 5mm, and center distance of each is 10mm. The outermost groove is 30mm away from the end surface. There are 15 Φ0.5×6 transverse blind holes, which are distributed along a circumference with a radius of 45 mm, with the position 50 mm from the upper surface to the end face as the center. The uppermost hole is 5 mm from the upper surface, the center interval between each two holes is 5°, and the center interval between the two holes at the bottom is 3°.

5. The comparative test block for phased array ultrasonic testing of weld joint micro-defects according to claim 4 is characterized by: The number of the Φ0.3 transverse through holes I is 8, the center of the hole is 50 mm away from the end surface, the center distance between adjacent holes is 5 mm, and the upper and lower holes are 5 mm away from the adjacent surface respectively; The number of the Φ0.3 transverse through holes II is 7, and the distances from the center of each hole to the upper surface and the side end surface are the same, namely 5mm, 10mm, 15mm, 20mm, 25mm, 30mm and 35mm respectively; The number of the Φ0.3 transverse through holes III is 10, the hole centers are horizontally arranged at a distance of 50 mm from the lower surface, the distance between adjacent hole centers is 5 mm, and the distance between the center of the outermost hole and the end surface on the b side is 5 mm.

6. The comparative test block for phased array ultrasonic testing of weld joint micro-defects according to claim 5 is characterized by: The number of the Φ0.5 transverse through holes I is 8, the center of the hole is 50 mm away from the end surface, the center spacing of adjacent holes is 5 mm, and the upper and lower holes are 5 mm away from the adjacent surface respectively; The number of the Φ0.5 transverse through holes II is 7, and the distances from the center of each hole to the upper surface and the side end surface are the same, namely 5mm, 10mm, 15mm, 20mm, 25mm, 30mm and 35mm respectively; The number of the Φ0.5 transverse through holes III is 10, the hole centers are horizontally arranged at a distance of 50 mm from the lower surface, the distance between adjacent hole centers is 5 mm, and the distance between the center of the outermost hole and the end surface on the side b is 5 mm.

7. A phased array ultrasonic detection method for micro-defects in welded joints, characterized by: The following steps are involved: 1) According to the thickness of the workpiece being tested, adjust the sensitivity using a conventional through-hole comparison test block in accordance with the requirements of the implementation standards NB / T 47013, DL / T 820 or DL / T 1718, and draw a DAC or TCG curve; 2) placing the phased array probe on the upper or lower side of the first comparison test block, the second comparison test block, and the third comparison test block, respectively, and finding the artificial reflector corresponding to the same depth as when drawing the DAC or TCG curve in step 1), and recording the echo equivalent values of the Φ0.1×6mm transverse blind hole, Φ0.5×6mm transverse blind hole, Φ0.3 transverse through hole, and Φ0.5 transverse through hole at the same depth, respectively. At the same time, record the echo equivalent values of different grooves at different depths, compare them with the detection sensitivity value set for the conventional through hole comparison test block, and draw a line graph of the difference in echo equivalents of different apertures at the same depth; 3) During actual inspection, a comparative analysis is performed based on the echo equivalent difference line graph and the thermal image morphology, color and defect reflection display of reference reflectors at different depths and apertures.

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