RU213099U1 - TEST SPECIMEN OF ULTRASONIC TESTING OF A FLANGED CONNECTOR WITH SCREW SOCKETS - Google Patents

Abstract

The utility model relates to devices for non-destructive testing of the structure and detection of defects in metal products and elements of nuclear power plants (NPP), can be used to test and evaluate the performance and efficiency of the ultrasonic testing (UT) system when discontinuities are detected by the ultrasonic testing system, as well as to ensure the ability to ultrasonic testing system to determine the characteristics and parameters of discontinuities and the quality of the metal of the flange connector of the NPP steam generator. The technical result achieved from the use of the utility model is to improve the quality of tuning of ultrasonic testing systems and the reliability of detection by ultrasonic testing systems of defects in flange connectors of steam generators of nuclear power plants. The technical result is achieved by the fact that the test sample of ultrasonic testing of a flange connector with threaded sockets is provided with discontinuities made between the threads along the thread direction, and the sample is made in the form of a part of a flat flange 115 mm thick, provided on the side of the upper surface with two blind threaded sockets, while in the first threaded socket, one discontinuity in the form of the first crack is made at a distance of 77 mm from the upper surface of the sample by pressing a cylindrical insert with a crack into a hole made in the body of the sample, and two discontinuities in the form of the first and second crack simulators are made by machining at a distance of 35 mm and 5 mm from the upper surface of the sample, respectively, in the second threaded socket, one discontinuity in the form of a second crack is made at a distance of 34 mm from the upper surface of the sample by pressing a cylindrical insert with a crack into the hole made in the body of the sample, and three discontinuities in the form of a third, fourth and fifth crack simulators, machined at a distance of 65 mm, 65 mm and 10 mm from the upper surface of the sample, respectively, while the sample is equipped with a first flat-bottom reflector with a diameter of 4.4 mm, which is located between the first threaded socket and the outer rounded edge sample, as well as a second flat-bottomed reflector with a diameter of 3.1 mm, which is located between the threaded sockets, and the distance of the flat-bottomed reflectors from the upper surface of the sample is 88 mm. 3 fig.

Description

The utility model relates to devices for non-destructive testing of the structure and detection of defects in metal products and can be used to test and evaluate the performance and efficiency of an ultrasonic testing (UT) system, as well as to ensure the ability of the UT system to determine the characteristics and parameters of discontinuities and the quality of the flange connector metal nuclear power plant steam generator.

Known test sample (reference block) ultrasonic testing of the surfaces of the gear teeth and the roots of the teeth, which is made in the form of a parallelepiped of steel, equipped with horizontal through holes of various sizes.

(CN 211318303 (U), G01N 29/04, G01N 29/30, published 08/21/2020) connector. The known IS contains only artificial reflectors, does not contain dangerous characteristic metal defects in the SG flanges such as realistic and real cracks, crack-like defects, and cannot be used for certification of ultrasonic testing systems.

The closest in technical essence is a device for ultrasonic testing of the internal thread of the flange, made in the form of a hollow cylinder with an internal thread. The test sample device is a part of a flange with a glass, along the thread direction of which the thread grooves contain three discontinuities in the form of artificial horizontal cracks of various depths. The thickness of the test piece is 40 mm and the curvature K = 1/80. (CN 207992126 (U), G01N 29/30, published 10/19/2018). The well-known tuning sample is equipped with blind threaded holes and is used to adjust the parameters of the flaw detector during ultrasonic testing of a specific size of flanged joints. It is not suitable for ultrasonic testing of other standard sizes. It is also not suitable for testing and certification of ultrasonic testing systems due to the absence of discontinuities in it in the form of real cracks.

The objective of the utility model is to create a test sample of ultrasonic testing of a flange connector with threaded sockets, which is made of steel of the same grade, has a design and dimensions similar to the controlled element, includes characteristic discontinuities of the metal and provides an opportunity for certification and evaluation of the effectiveness of the ultrasonic testing system to reliably detect discontinuities in the form of cracks of various origins, including determining the characteristics and parameters of discontinuities, and using them to evaluate the quality of the metal.

The technical result achieved from the use of the utility model is to improve the quality of tuning of ultrasonic testing systems and the reliability of detection by ultrasonic testing systems of defects in flange connectors of steam generators of nuclear power plants.

The technical result is achieved by the fact that the test sample of ultrasonic testing of a flange connector with threaded sockets is provided with discontinuities made between the threads along the thread direction, and the sample is made in the form of a part of a flat flange, 115 mm thick, provided on the side of the upper surface with two blind threaded sockets, with In this case, in the first threaded socket, one discontinuity in the form of the first crack is made at a distance of 77 mm from the upper surface of the sample by pressing a cylindrical insert with a crack into a hole made in the sample body, and two discontinuities in the form of the first and second crack simulators are made by machining at a distance of 35 mm and 5 mm from the upper surface of the sample, respectively, in the second threaded socket, one discontinuity in the form of a second crack is made at a distance of 34 mm from the upper surface of the sample by pressing a cylindrical insert with a crack into the hole made in the body of the sample, and three discontinuities in the form of t third, fourth and fifth crack simulators, machined at a distance of 65 mm, 65 mm and 10 mm from the upper surface of the sample, respectively, while the sample is equipped with the first flat-bottomed reflector with a diameter of 4.4 mm, which is located between the first threaded socket and the outer rounded edge sample, as well as a second flat-bottomed reflector with a diameter of 3.1 mm, which is located between the threaded sockets, and the distance of the flat-bottomed reflectors from the upper surface of the sample is 88 mm.

The technical result is also achieved by the fact that the sample is made with M48 blind threaded sockets with a threaded part length of 90 mm and a thread pitch of 5 mm, with a distance between the vertical axes of the threaded sockets of 102.3 mm at a distance of the vertical axes of the threaded sockets from the outer rounded edge of the flange 44, 0-46.0mm;

the first crack is 15 mm wide and 6.4 mm deep, and the second crack is 10 mm wide and 3.2 mm deep;

the opening width of all crack simulators is 0.3±0.1 mm; in the first threaded socket, the first crack simulator is made 26.9 mm wide and 3.2 mm deep, and the second crack simulator is made 26.9 mm wide and 3.2 mm deep;

in the second threaded socket, the third crack simulator is made 31.0 mm wide and 6.4 mm deep, the fourth crack simulator - 26.9 mm wide and 3.2 mm deep, the fifth crack simulator - 26.9 mm wide and 3.2 mm deep mm;

the tops of the discontinuities are located at an angle of inclination of the vertical section passing through the top of the discontinuity and the axis of the threaded socket to the vertical section passing through the axes of the threaded sockets, and the top of the first crack is made at an angle of 0°, the top of the second crack is at an angle of 90°, the top of the first imitator cracks - at an angle of 125°, the top of the second crack simulator - at an angle of 35°, the top of the third crack simulator - at an angle of 0°, the top of the fourth crack simulator - at an angle of 150°, the top of the fifth crack simulator - at an angle of 25°;

the axis of the first reflector is located at a distance of 39 mm from the axis of the first threaded socket, and the axis of the second flat-bottomed reflector is located at a distance of 41 mm from the axis of the first threaded socket.

The utility model, which has various cracks of different origin and location in the body of the test sample, provides an increase in the reliability of detecting defects in the form of cracks in the flange connectors of steam generators of nuclear power plants by ultrasonic testing systems.

The design of the test sample according to the utility model includes the following structural elements (figure 1-2), where:

G1, G2 - the first and second blind threaded socket;

T1, T2 - cracks made in the first and second threaded seat, respectively;

IT1, IT2 - the first and second crack simulators made in the first threaded seat;

IT3, IT4, IT5 - the third, fourth and fifth crack simulators made in the second threaded seat;

OT1, OT2 - flat bottom reflectors;

α - the angle of inclination of the tops of discontinuities;

1 - outer rounded edge of the sample;

2 - preparation of a sample for implantation;

3 - stress concentrator;

4 - crack;

5 - cylindrical insert with a crack.

The test sample according to the utility model (Fig.1,2) is a part (in the form of a rounded plate with an outer rounded edge 1) of a flat flange, for example, a flanged connector for a manhole hatch Du500 of the second circuit of the NPP steam generator, on a scale of 1: 1 with the following overall dimensions dimensions: length Х=192 mm, width Y=150 mm, thickness Z=115 mm. On the side of the upper surface, the sample is equipped with two blind threaded sockets M48 (G1 and G2) with a threaded part length of 90 mm, a thread pitch of 5 mm, and is made of steel grade 10GN2MFA with a surface roughness of the sample not worse than R _a 6.3 μm. The distance between the axes of the threaded sockets is 102.3 mm, with the distance of the centers of the threaded sockets from the rounded edge 1 of the flange 44.0-46.0 mm (figure 2).

The test sample according to the utility model contains embedded discontinuities (defects) in the form of cracks and crack simulators, which provide the possibility of certification and evaluation of the performance and efficiency of the ultrasonic testing system to reliably detect the parameters of discontinuities.

Discontinuities in the threaded sockets are made between the threads along the thread direction (figure 1)

In the first threaded socket G1 discontinuities are made (Fig.1,2) in the form of the first crack T1 and two crack simulators IT1 and IT2. The first crack T1 with a width of 15 mm and a depth of 6.4 mm is made by pressing a cylindrical insert 5 (figure 3) with a crack into a hole made in the body of the sample, at a distance of 77 mm from the upper surface of the sample. The discontinuity in the form of the first crack simulator IT1 with a width of 26.9 mm and a depth of 3.2 mm was machined at a distance of 35 mm from the upper surface of the sample, and the second discontinuity in the form of a second crack simulator IT2 with a width of 26.9 mm and a depth of 3.2 mm made by machining at a distance of 5 mm from the upper surface of the sample. Crack simulators IT1 and IT2 are made with an opening width of 0.3±0.1 mm.

In the second threaded socket G2 (figure 1, 2) discontinuities are made in the form of a second crack T2 and three crack simulators IT3, IT4 and IT5. The second crack T2 with a width of 10 mm and a depth of 3.2 mm is made by pressing a cylindrical insert 5'' (Fig.3) with a crack into a hole made in the body of the sample at a distance of 34 mm from the upper surface of the sample. The discontinuity in the form of the third crack simulator IT3 31.0 mm wide and 6.4 mm deep was machined at a distance of 65 mm from the upper surface of the sample, the discontinuity in the form of the fourth crack simulator IT4 26.9 mm wide and 3.2 mm deep was machined by processing at a distance of 65 mm from the upper surface of the sample, the discontinuity in the form of the fifth crack simulator IT4 26.9 mm wide and 3.2 mm deep was machined at a distance of 5 mm from the upper surface of the sample. The opening width of crack simulators ITZ, IT4 and IT5 is 0.3±0.1 mm.

The tops of the discontinuities are located at an angle of inclination a (figure 2) of the vertical section passing through the top of the discontinuity and the axis of the threaded socket, to the vertical section passing through the axes of the first and second threaded sockets. For the first crack, the angle of inclination of its tip is 0°, for the second crack - 90°, for the first crack simulator -125°, for the second crack simulator - 35°, for the third crack simulator - 0°, for the fourth crack simulator - 150°, for the fifth crack simulator - 25°.

The test sample according to the utility model is also equipped with two flat-bottom reflectors OT1 and OT2, made at a distance of 88 mm from the upper surface of the sample. The first reflector is made with a diameter of 4.4 mm, and the second reflector = with a diameter of 3.1 mm. The axis of the first flat-bottomed reflector OT1 is placed between the first threaded socket and the outer rounded edge 1 of the sample at a distance of 39 mm from the axis of the first threaded socket, and the axis of the second flat-bottomed reflector OT2 is placed between the axes of the threaded sockets at a distance of 41 mm from the axis of the first threaded socket. The reflectors are made by known methods of mechanical processing of metals and ensure that the quality of the metal is assessed in accordance with the current standards for quality assessment.

A test sample according to the utility model is used to test the operability and efficiency of ultrasonic testing systems for metal flanges of steam generators of VVER-type NPPs when certifying newly developed ultrasonic testing methods and systems and evaluating the possibility of using them in testing NPP metal. The number and location of discontinuities in the sample provides an increase in the reliability of detecting defects in the form of cracks in the flange connectors of steam generators of nuclear power plants by ultrasonic testing systems.

Cracks T1 and T2 can be cut out of defective NPP equipment or obtained artificially and introduced (implanted) into the test sample by known methods, including (figure 2, 3):

- production of blank 2 samples from the metal of the test sample for implantation;

- execution in the workpiece 2 of the stress concentrator 3 in the form of a notch, the application of a variable load F to the workpiece 2 until the formation of a crack 4, for example, a fatigue crack of the required depth, removal of the surface layer of the material with a thickness not less than the depth of the notch;

- cutting the implanted sample in the form of a cylindrical insert 5 of the required size with the location of the crack 4 or on the side surface of the insert (along or across the axis of the cylinder), or on the end surface;

- grinding and polishing of the surface of the cylindrical insert 5 with a crack 4 and its testing;

- production in the test sample according to the utility model in the required place of a through hole with a diameter smaller than the diameter of the cylindrical insert 5 with a crack;

- grinding and polishing the surface of the resulting hole;

- hot fit by pressing at a temperature of less than 500°C of a cylindrical insert 5 into the hole of the test sample with the placement of crack 4 in the required location (at the required depth and required angle a);

- welding a hole in the test piece using the metal of the test piece;

- machining of the surface of the test piece. (SU 750324, G01N 1/28, published 07/28/1980; CN 101710040,

G01N 1/28; G01N 1/32, published 05/19/2010; WO 9819155, G01M 19/00, G01N 29/30, published 05/07/1998)

In the manufacture of a test sample according to a utility model for implanting cracks T1 and T2, cylindrical inserts 5 and 5'' were made with cracks 4 placed across the axis of the insert and in their middle (figure 3), and holes for their hot fit by pressing were made along external thread sockets G1 and G2 (figure 2)

Crack simulators at the required depth and location angle α are obtained by known methods of milling and/or electroerosion.

In the process of certification testing by the system and/or method of ultrasonic testing, the test sample according to the utility model ensures the identification of all discontinuities, the determination and evaluation of their sizes and parameters, and allows, based on the characteristics obtained, to evaluate the quality of the metal of the flange connector with threaded sockets of the existing NPP equipment.

Claims (8)

1. A test sample of ultrasonic testing of a flange connector with threaded sockets, equipped with discontinuities made between the threads along the thread direction, characterized in that the sample is made in the form of a part of a flat flange 115 mm thick, provided on the side of the upper surface with two blind threaded sockets, while in the first threaded socket, one discontinuity in the form of the first crack is made at a distance of 77 mm from the upper surface of the sample by pressing a cylindrical insert with a crack into a hole made in the body of the sample, and two discontinuities in the form of the first and second crack simulators are made by machining at a distance of 35 mm and 5 mm from the upper surface of the sample, respectively, in the second threaded socket, one discontinuity in the form of a second crack is made at a distance of 34 mm from the upper surface of the sample by pressing a cylindrical insert with a crack into the hole made in the body of the sample, and three discontinuities in the form of the third, fourth and the fifth crack simulators, machined at a distance of 65 mm, 65 mm and 10 mm from the upper surface of the sample, respectively, while the sample is equipped with the first flat-bottomed reflector with a diameter of 4.4 mm, which is located between the first threaded socket and the outer rounded edge of the sample, and also a second flat-bottom reflector with a diameter of 3.1 mm, which is located between the threaded sockets, and the distance of the flat-bottom reflectors from the upper surface of the sample is 88 mm. 2. The test specimen according to claim 1, characterized in that it is made with M48 blind threaded sockets with a threaded part length of 90 mm and a thread pitch of 5 mm, with a distance between the vertical axes of the threaded sockets of 102.3 mm with a distance of the vertical axes of the threaded sockets from the outer rounded edge of the flange 44.0-46.0 mm. 3. Test specimen according to claim 1, characterized in that the first crack is 15 mm wide and 6.4 mm deep, and the second crack is 10 mm wide and 3.2 mm deep. 4. Test specimen according to claim 1, characterized in that the opening width of all crack simulators is 0.3 ± 0.1 mm. 5. Test specimen according to claim 1, characterized in that in the first threaded socket the first crack simulator is made 26.9 mm wide and 3.2 mm deep, and the second crack simulator is made 26.9 mm wide and 3.2 mm deep. 6. The test sample according to claim 1, characterized in that in the second threaded socket the third crack simulator is made 31.0 mm wide and 6.4 mm deep, the fourth crack simulator is 26.9 mm wide and 3.2 mm deep, the fifth crack simulator - 26.9 mm wide and 3.2 mm deep. 7. The test specimen according to claim 1, characterized in that the tops of the discontinuities are located at an angle of inclination of the vertical section passing through the top of the discontinuity and the axis of the threaded socket to the vertical section passing through the axes of the threaded sockets, and the top of the first crack is made at an angle of 0° , the tip of the second crack is at an angle of 90°, the tip of the first crack simulator is at an angle of 125°, the tip of the second crack simulator is at an angle of 35°, the tip of the third crack simulator is at an angle of 0°, the tip of the fourth crack simulator is at an angle of 150°, the top of the fifth crack simulator is at an angle of 25°. 8. Test specimen according to claim 1, characterized in that the axis of the first reflector is located at a distance of 39 mm from the axis of the first threaded socket, and the axis of the second flat-bottomed reflector is located at a distance of 41 mm from the axis of the first threaded socket.

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