Verification test block for phased array ultrasonic detection technology

Abstract

The utility model discloses a phased array ultrasonic testing technology verification test block, which comprises a test block body made of the same material as a target product to be tested, the test block body is arranged in a shape of the target product, a welding seam is arranged on the test block body, the welding seam is formed by adopting the same welding process as the target product, and the test block body is made of a stainless steel material. The specification and the excess weld metal of the welding seam are consistent with those of a target product; welding defects are arranged on the welding seam, and the welding defects comprise one or more combinations of an upper surface groove, a lower surface groove, a longitudinal crack, a transverse crack, incomplete fusion, incomplete penetration, a strip-shaped defect, a circular defect and slag inclusion. According to the utility model, the test block body and the welding defects thereof are designed, so that the manufactured test block body can be used for verifying the accuracy, detectability and reliability of a phased array ultrasonic inspection technology instead of a ray inspection technology in the manufacturing and mounting process of nuclear safety level equipment, and the nuclear safety is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of nondestructive testing, and particularly relates to a phased array ultrasonic testing technology verification test block. Background Technique

[0002] At present, China's nuclear power construction has entered a new stage of rapid development, and the requirements for the safety and technology of nuclear power plant construction are getting higher and higher. Among them, during the construction of nuclear power plants, there are a large number of welded joints, and their quality will directly affect the safe operation of nuclear power plants.

[0003] China's nuclear power units are mainly designed and constructed according to mature foreign standards and specifications. The corresponding standards and specifications mainly include RCC-M "Rules for the Design and Construction of Mechanical Equipment in the Nuclear Island of Pressurized Water Reactor Nuclear Power Plants" in France and ASME "Boiler and Pressure Vessel Code of the American Society of Mechanical Engineers", etc. For the volumetric inspection method of nuclear-grade pipe welds during the manufacturing and installation stages of nuclear safety-class equipment, both RCC-M "Rules for the Design and Construction of Mechanical Equipment in the Nuclear Island of Pressurized Water Reactor Nuclear Power Plants" in France and ASME "Boiler and Pressure Vessel Code of the American Society of Mechanical Engineers" in the United States stipulate that ray inspection must be carried out at least. The advantage of ray inspection is that it is more sensitive to volumetric defects (such as pores, slag inclusions, etc.), and the inspection results can be directly reflected on the film. However, ray inspection also has certain limitations, mainly reflected in the detection of area-type defects (such as lack of fusion, lack of penetration, etc.) (the relative direction of the ray angle and the defect), the inability to locate defects, occupying a large amount of time windows, and having relatively high radiation protection requirements. Compared with ray inspection, the advantage of ultrasonic inspection is that it has a better detection effect on area-type defects and can quantitatively measure the length and height of corresponding defects.

[0004] In recent years, with the development of wafer and probe manufacturing, instrument manufacturing, and computer software technology, the phased array ultrasonic testing technology (PAUT) excites the wafers arranged in an orderly manner on the phased array probe according to the set sequence and delay time, controls the shape and direction of the emitted ultrasonic beam (wavefront), realizes ultrasonic beam scanning, deflection, and focusing, has higher detection accuracy, sensitivity, and defect detection rate. At the same time, it uses a combination of mechanical scanning and electronic scanning methods to achieve defect computer imaging, forming data records that can be reviewed and remotely transmitted, and can solve the limitations of low detection rate of area-type defects and radiation protection in ray detection, and has great advantages.

[0005] The characteristics of the research and development of the fourth-generation nuclear energy technology in China are obvious, namely, the construction period is short and the progress is urgent. At the same time, there are a large number of welds with special structural forms in the equipment and components, and traditional X-ray film detection cannot be carried out effectively, and other inspection methods are urgently needed. Under comprehensive consideration, PAUT can be used as one of the methods for volume inspection of such welds, but the reliability of PAUT needs to be fully technically verified. The most critical part of technical verification is to have sufficiently representative simulation verification blocks to evaluate the reliability of PAUT replacing X-ray detection. Therefore, how to design a phased array ultrasonic detection technology verification block is a technical problem that needs to be solved urgently. Utility Model Content

[0006] In order to solve the above technical problems, the utility model provides a phased array ultrasonic detection technology verification test block, which can verify the accuracy, detectability and reliability of phased array ultrasonic inspection technology instead of X-ray inspection technology during the manufacturing and installation of nuclear safety-level equipment, thereby ensuring nuclear safety.

[0007] The utility model adopts the following technical solution to solve the technical problem: a phased array ultrasonic testing technology verification test block, comprising: a test block body made of the same material as a target product to be inspected, the test block body is shaped like the shape of the target product, a weld is provided on the test block body, the weld is formed by the same welding process as the target product, and the specification and excess height of the weld are consistent with those of the target product; the weld is provided with welding defects, and the welding defects include one or more combinations of upper surface grooves, lower surface grooves, longitudinal cracks, transverse cracks, lack of fusion, lack of penetration, strip defects, circular defects, and slag inclusions.

[0008] As a further improvement of the present invention, the welding defects are configured as N in total according to their type, size and weld thickness regional distribution, the test block body is provided with M, and the N welding defects are evenly distributed to the welds of the M test block bodies.

[0009] As a further improvement of the present invention, when the thickness of the test block body is less than or equal to 13 mm, the welding defects distributed within the 1 / 2 thickness range of the outer surface of the weld account for at least 20%, and the welding defects distributed within the 1 / 2 thickness range of the inner surface of the weld account for at least 40%;

[0010] When the thickness of the test block body is greater than 13 mm, the welding defects distributed within 1 / 3 of the thickness of the outer surface of the weld account for at least 20%, the welding defects distributed within the middle 1 / 3 of the thickness of the weld account for at least 20%, and the welding defects distributed within 1 / 3 of the thickness of the inner surface of the weld account for at least 40%.

[0011] As a further improvement of the present utility model, at least two of the welding defects are distributed perpendicular to the fusion line of the weld seam, and the remaining welding defects are distributed along the circumferential direction of the weld seam.

[0012] As a further improvement of the present utility model, the inspection method of the test block body is single-sided scanning or double-sided scanning. Taking the center line of the weld seam as the boundary, single-sided scanning means: using a phased array ultrasonic probe to scan the part on one side of the center line of the weld seam; double-sided scanning means: using a phased array ultrasonic probe to scan the parts on both sides of the center line of the weld seam.

[0013] As a further improvement of the present utility model, it is defined that the part on one side of the center line of the weld seam and close to the phased array ultrasonic probe is the proximal side, and the part on the other side of the center line of the weld seam and far from the phased array ultrasonic probe is the distal side. When using the single-sided scanning method, the proportion of the welding defects distributed on the distal side is at least 30%, and the proportion of the area-type welding defects distributed on the proximal side is at least 30%.

[0014] As a further improvement of the present utility model, the test block body is also provided with heat-affected zones on both sides of the weld seam, and crack defects are provided in the heat-affected zones.

[0015] As a further improvement of the present utility model, the inner surface of the test block body at the weld seam is provided with an inspection surface formed by boring.

[0016] As a further improvement of the present utility model, the welding defects are natural defects generated by welding or artificial defects generated by machining.

[0017] As a further improvement of the present utility model, the test block body is any one or a combination of a straight pipe fitting, an elbow pipe fitting, and a tee pipe fitting. The outer diameters and wall thicknesses of the M test block bodies include at least three specifications of the maximum, minimum, and intermediate values of the target product.

[0018] The beneficial effects of the present utility model are as follows: The present utility model provides a phased array ultrasonic testing technology verification test block. By designing the test block body and its welding defects, the fabricated test block body can verify the accuracy, detectability, and reliability of replacing radiographic testing technology with phased array ultrasonic inspection technology during the manufacturing and installation processes of nuclear safety-class equipment, ensuring nuclear safety. At the same time, by specifying test blocks of various specifications and single-sided and double-sided scanning, and clarifying the requirements for the type of natural defects, their own height, their own length, and the regional distribution of weld thickness, blind testing and open testing of inspectors can be carried out using the fabricated test block body, comprehensively testing the rationality of the inspection procedure, the reliability of the inspection equipment, and the compliance of the inspector's skills, and further verifying the accuracy, detectability, and reliability of the phased array ultrasonic inspection technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a perspective view of the phased array ultrasonic testing technology verification test block of the present utility model;

[0020] Figure 2 is a top view of the weld of the phased array ultrasonic testing technology verification test block of the present utility model when unfolded;

[0021] Figure 3 is a front view of the weld of the phased array ultrasonic testing technology verification test block of the present utility model when unfolded;

[0022] Figure 4 is a partial cross-sectional view of the phased array ultrasonic testing technology verification test block of the present utility model;

[0023] Figure 5 is a perspective view of another embodiment of the phased array ultrasonic testing technology verification test block of the present utility model.

[0024] The following descriptions are made in conjunction with the accompanying drawings:

[0025] 1. Test block body; 101. Weld; 1011. Proximal side; 1012. Distal side;

[0026] 102. Heat affected zone; 103. Inspection surface; a. Upper surface groove; b. Lower surface groove; c. Longitudinal crack; d. Transverse crack; e. Lack of fusion; f. Incomplete penetration; g. Strip-shaped defect; h. Round defect; i. Slag inclusion. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] The following describes in detail the preferred embodiments of the present utility model in conjunction with the accompanying drawings.

[0028] Refer to Figures 1 to 5, the present utility model provides a phased array ultrasonic testing technology verification test block, including a test block body 1. Before designing the test block body 1, it is first necessary to sort out the target product to be nondestructively inspected, including at least the outer diameter, wall thickness, material grade, safety level, specification level and inspection method of the target product. The test block body 1 is made of the same material as the target product (including but not limited to the same grade, the same chemical composition, the same manufacturing process, the same heat treatment state), and the base metal of the test block body 1 shall be subjected to nondestructive inspection in accordance with the requirements of the target product, including the technical specification and the corresponding manufacturing standards (such as ASME or RCCM), and pass the acceptance inspection.

[0029] Furthermore, the test block body 1 is configured to be shaped like the target product. In this embodiment, the target product specifically refers to the pipeline of the target nuclear power project. The test block body 1 can be any one or a combination of straight pipe fittings, elbow pipe fittings, and tee pipe fittings, such as Figure 1 shown, the test block body 1 is formed by welding two straight pipe fittings; or as Figure 5 shown, the test block body 1 is formed by welding a straight pipe fitting and a tee pipe fitting.

[0030] Refer to Figure 1 , a weld 101 is provided on the test block body 1. The weld 101 is formed by using the same welding process as the target product, and the specifications and reinforcement height of the weld 101 are the same as those of the target product. At the same time, the surface roughness of the weld 101 of the test block body 1 shall not be higher than the surface roughness requirement of the weld of the target product.

[0031] Refer to Figure 2 and Figure 3 , welding defects are provided on the weld 101 in the present utility model. The welding defects include one or a combination of an upper surface groove a, a lower surface groove b, a longitudinal crack c, a transverse crack d, lack of fusion e, incomplete penetration f, strip-shaped defects g, circular defects h, and slag inclusions i. The present utility model can provide verification for the accuracy, detectability and reliability of the phased array ultrasonic inspection technology replacing the ray inspection technology in the manufacturing and installation processes of nuclear safety-class equipment by using the manufactured test block body 1, and ensure nuclear safety.

[0032] It is worth mentioning that the welding defects in the present utility model are configured into N according to their types (i.e., upper surface groove a, lower surface groove b, longitudinal crack c, transverse crack d, lack of fusion e, incomplete penetration f, strip defect g, circular defect h, slag inclusion i), their own dimensions (including their own height and length), and the weld thickness area distribution. The test block body 1 is provided with M. The N welding defects are evenly distributed into the welds 101 of the M test block bodies 1. That is, when manufacturing, the corresponding N welding defects can be randomly combined, and each test block body 1 contains N / M welding defects. The present utility model adopts the form of combining M test block bodies 1 for inspection, and clarifies the requirements for the welding defect type, its own height, its own length, and the weld thickness area distribution. By using the manufactured test block body 1 to conduct blind tests and explicit tests on inspectors, the rationality of the inspection procedure, the reliability of the inspection equipment, and the compliance of the inspectors' skills can be comprehensively tested, and further verification can be provided for the accuracy, detectability, and reliability of the phased array ultrasonic inspection technology.

[0033] Among them, the welds 101 in the test block body 1 should be subjected to radiographic inspection and TOFD (Time Of Flight Diffraction) inspection to qualitatively and quantitatively analyze the defects existing in the welds.

[0034] In order to verify the inspection range and detectability of PAUT, the outer diameter and wall thickness of the M test block bodies 1 at least include three specifications: the maximum, minimum, and intermediate values of the target product. In addition, for the target product with a diameter of 159 mm to 500 mm, the curvature radius of the target product should be 0.9 times to 1.5 times the curvature radius of the test block body 1.

[0035] In addition, as Figure 4 shown, an inspection surface 103 formed by boring is provided on the inner surface of the test block body 1 at the weld 101. The inspection surface 103 is used to ensure the effective implementation of phased array ultrasonic inspection.

[0036] Referring to Figure 1 and Figure 5 , the test block body 1 is also provided with heat affected zones 102 on both sides of the weld 101. As the name implies, the heat affected zone 102 is the area around the weld 101 that is affected by heat during welding. Crack defects are provided in the heat affected zones 102, including but not limited to longitudinal crack c and transverse crack d. In addition to inspecting the weld 101, the present utility model can also inspect the heat affected zones 102, and further verify the accuracy, detectability, and reliability of the phased array ultrasonic inspection technology replacing the radiographic inspection technology during the manufacturing and installation processes of nuclear safety class equipment, ensuring nuclear safety.

[0037] In this embodiment, the welding defects are natural defects generated by welding or artificial defects generated by machining. The natural defects in the test block body 1 are typical welding defects that are likely to occur during the welding process of the weld 101, such as longitudinal crack c, transverse crack d, lack of fusion e, lack of penetration f, strip-shaped defect g, circular defect h, etc., and at least 50% of the welding defects should be area-type defects, such as lack of fusion e, lack of penetration f, longitudinal crack c, transverse crack d, etc., and at least 20% of the welding defects are volume-type defects, such as slag inclusion i, etc.

[0038] Furthermore, in order to more realistically simulate the actual defect situation of the target product, the welding defects of the test block body 1 are designed according to the following requirements.

[0039] When the thickness of the test block body 1 is less than or equal to 13 mm, the proportion of welding defects distributed within the outer surface 1 / 2 thickness range of the weld 101 is at least 20%, and at the same time, the proportion of welding defects distributed within the inner surface 1 / 2 thickness range of the weld 101 is at least 40%; when the thickness of the test block body 1 is greater than 13 mm, the proportion of welding defects distributed within the outer surface 1 / 3 thickness range of the weld 101 is at least 20%, the proportion of welding defects distributed within the middle 1 / 3 thickness range of the weld 101 is at least 20%, and at the same time, the proportion of welding defects distributed within the inner surface 1 / 3 thickness range of the weld 101 is at least 40%.

[0040] At least two welding defects are distributed perpendicular to the fusion line of the weld 101, and the remaining welding defects are distributed along the circumferential direction of the weld 101.

[0041] For various types of defects in the test block body 1: the length tolerance of the strip-shaped defect g and the circular defect h should be controlled within ±1.0 mm; the length tolerance of the longitudinal crack c, transverse crack d, lack of fusion e, and lack of penetration f should be controlled within ±1.0 mm, and the height tolerance should be controlled within ±0.1 mm.

[0042] For the strip-shaped defect g in the test block body 1, the set value of its length refers to the critical non-compliant defect size of the strip-shaped defect for radiographic inspection in ASME Ⅲ, Section NC-5320, 2004 Edition and the single defect length size allowed for Class I welds in DL / T 1718, 2017 Edition; the height should not exceed the single defect height limit value of Class I welds in DL / T 1718, 2017 Edition, that is, the height is not greater than 2 mm.

[0043] For the circular defect h in the test block body 1, its size should not be greater than the maximum allowable size of the circular defect for radiographic inspection in ASME Ⅲ, Section NC-5320, 2004 Edition, that is, the minimum value is 4 mm.

[0044] For longitudinal crack c, transverse crack d, lack of fusion e, and lack of penetration f defects, since there is no requirement for the critical over-standard size in the acceptance criteria for radiographic inspection in Section NC-5320 of ASME III, Division 1 (2004 Edition), therefore, the principle for determining the sizes of longitudinal crack c, transverse crack d, lack of fusion e, and lack of penetration f defects in the test block is as follows: The length value of the defects is set with reference to the critical over-standard defect sizes of strip-shaped defects for radiographic inspection in Section NC-5320 of ASME III, Division 1 (2004 Edition) and the allowable single defect length sizes for Class I welds in DL / T 1718 (2017 Edition); the height shall not exceed the limit of the height of a single defect for Class I welds in DL / T 1718 (2017 Edition), that is, the height is not greater than 2 mm.

[0045] It should be noted that considering the possible single-sided scanning situation in the actual field, therefore, the inspection methods of the test block body 1 are set with two methods: single-sided scanning and double-sided scanning.

[0046] As Figure 4 shown, taking the center line of the weld 101 as the boundary, single-sided scanning means: using a phased array ultrasonic probe to scan the part on one side of the center line of the weld 101; double-sided scanning means: using a phased array ultrasonic probe to scan the parts on both sides of the center line of the weld 101.

[0047] Among them, the part on one side of the center line of the weld 101 and close to the phased array ultrasonic probe is defined as the proximal side 1011, and the part on the other side of the center line of the weld 101 and far from the phased array ultrasonic probe is defined as the distal side 1012. When using the single-sided scanning method, the proportion of welding defects distributed on the distal side 1012 is at least 30%, and the proportion of area-type welding defects distributed on the proximal side 1011 is at least 30%.

[0048] In order to make the purpose, technical solutions, and advantages of the present utility model clearer, the following takes the main steam / main feed water system pipeline of a high-temperature gas-cooled reactor as an example for detailed description. After sorting out, the material grade of one section of the main steam / main feed water system pipeline is ASME SA-335P91, and the specification parameters are shown in Table 1 below:

[0049] Table 1

[0050]

[0051] Combined with the specification parameters of the target product in Table 1 and the specification range of the weld 101 for which the PAUT technology is to be used, the information of the PAUT technology verification test block designed is shown in Table 2 below:

[0052] Table 2

[0053]

[0054] With the specification size of Taking the verification test block with the specification size as an example, the inspection method is bilateral scanning. The designed welding defect conditions are shown in Table 3 below, including at least the following 20 defects:

[0055] Table 3

[0056]

[0057]

[0058] Taking the verification test block with the specification size of as an example, the inspection method is unilateral scanning. The designed welding defect conditions are shown in Table 4 below, including at least the following 20 defects:

[0059] Table 4

[0060]

[0061]

[0062] According to the corresponding test block size, the welding defects in Table 3 and Table 4 are fabricated. When fabricating each test block body 1, the corresponding 20 defects can be randomly combined. 4 - 5 defects can be fabricated in each test block body 1, that is, 4 - 5 bilateral scanning test block bodies 1 and 4 - 5 unilateral scanning test block bodies 1 are fabricated for each specification.

[0063] It can be seen that taking the design of the phased array ultrasonic inspection technology verification test block for the main steam / main feed water system pipeline of the high-temperature gas-cooled reactor as an example, the present utility model elaborates in detail on the design of the test block body 1 and the design of welding defects, stipulates each specification and the unilateral scanning and bilateral scanning test blocks, clarifies the requirements for the natural defect type, self-height, self-length, and weld thickness area distribution. By using the fabricated test block body 1 to conduct blind tests and open tests on inspectors, the rationality of the inspection procedure, the reliability of the inspection equipment, and the compliance of the inspector skills can be comprehensively tested, providing verification for the accuracy, detectability, and reliability of the phased array ultrasonic inspection technology replacing the ray inspection technology during the manufacturing and installation processes of nuclear safety-class equipment, and ensuring nuclear safety.

[0064] In the above description, many specific details are set forth in order to fully understand the present utility model. However, the above description is only a preferred embodiment of the present utility model, and the present utility model can be implemented in many other ways different from those described herein. Therefore, the present utility model is not limited by the specific embodiments disclosed above. At the same time, any person skilled in the art can make many possible changes and modifications to the technical solution of the present utility model by using the methods and technical contents disclosed above without departing from the scope of the technical solution of the present utility model, or modify it into an equivalent embodiment with equivalent changes. All those that do not depart from the content of the technical solution of the present utility model, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present utility model still fall within the scope of protection of the technical solution of the present utility model.

Claims

1. A phased array ultrasonic testing technology verification test block, characterized in that, Including: A test block body (1) made of the same material as the target product to be inspected, the test block body (1) being configured in imitation of the shape of the target product, with a weld seam (101) provided on the test block body (1), the weld seam (101) being formed by the same welding process as the target product, and the specifications and reinforcement height of the weld seam (101) being consistent with those of the target product; welding defects are provided on the weld seam (101), and the welding defects include one or a combination of an upper surface groove (a), a lower surface groove (b), a longitudinal crack (c), a transverse crack (d), lack of fusion (e), incomplete penetration (f), strip-shaped defects (g), circular defects (h), slag inclusions (i).

2. The phased array ultrasonic testing technology verification test block according to claim 1, wherein: The welding defects are configured into N according to their types, their own dimensions and their distribution in the weld thickness region, and M test block bodies (1) are provided. The N welding defects are evenly distributed into the weld seams (101) of the M test block bodies (1).

3. The phased array ultrasonic testing technology verification test block according to claim 2, characterized in that: When the thickness of the test block body (1) is less than or equal to 13 mm, the proportion of the welding defects distributed within the outer surface 1 / 2 thickness range of the weld seam (101) is at least 20%, and at the same time the proportion of the welding defects distributed within the inner surface 1 / 2 thickness range of the weld seam (101) is at least 40%; When the thickness of the test block body (1) is greater than 13 mm, the proportion of the welding defects distributed within the outer surface 1 / 3 thickness range of the weld seam (101) is at least 20%, the proportion of the welding defects distributed within the middle 1 / 3 thickness range of the weld seam (101) is at least 20%, and at the same time the proportion of the welding defects distributed within the inner surface 1 / 3 thickness range of the weld seam (101) is at least 40%.

4. The phased array ultrasonic testing technology verification test block according to claim 3, characterized in that: At least two of the welding defects are distributed perpendicular to the fusion line of the weld seam (101), and the remaining welding defects are distributed along the circumferential direction of the weld seam (101).

5. The phased array ultrasonic testing technology verification test block according to claim 2, characterized in that: The inspection method of the test block body (1) is single-sided scanning or double-sided scanning. Taking the center line of the weld seam (101) as the boundary, single-sided scanning means: scanning a part on one side of the center line of the weld seam (101) through a phased array ultrasonic probe; double-sided scanning means: scanning parts on both sides of the center line of the weld seam (101) through a phased array ultrasonic probe.

6. The phased array ultrasonic testing technology verification test block according to claim 5, characterized in that: Defining the part on one side of the center line of the weld seam (101) and close to the phased array ultrasonic probe as the proximal side (1011), and the part on the other side of the center line of the weld seam (101) and far from the phased array ultrasonic probe as the distal side (1012). When using the single-sided scanning method, the proportion of the welding defects distributed on the distal side (1012) is at least 30%, and the proportion of the area-type welding defects distributed on the proximal side (1011) is at least 30%.

7. The phased array ultrasonic testing technology verification test block according to claim 1, wherein: The test block body (1) is further provided with heat-affected zones (102) on both sides of the weld seam (101), and crack defects are provided in the heat-affected zones (102).

8. The phased array ultrasonic testing technology verification test block according to claim 1, characterized in that: The inner surface of the test block body (1) is provided with an inspection surface (103) formed by boring at the weld (101).

9. The phased array ultrasonic testing technology verification test block according to claim 1, characterized in that: The welding defects are natural defects generated by welding or artificial defects generated by machining methods.

10. The phased array ultrasonic testing technology verification test block according to claim 2, characterized in that: The test block body (1) is any one or a combination of a straight pipe fitting, an elbow pipe fitting, and a tee pipe fitting. The outer diameters and wall thicknesses of the M test block bodies (1) include at least three specifications of the maximum, minimum, and intermediate values of the target product.

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