• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    Ultrasonic inspection system comprising an emitting ultrasound sensor (1) configured to send an ultrasonic beam (5) through a means (3) to be inspected, and a receiving ultrasound sensor (2) configured to receive the ultrasonic beam (5), each ultrasound sensor (1, 2) comprising a piezoelectric crystal (6) and a sole (7), the sole (7) being available on the surface of the medium (3) to be inspected, and having the sole (7) an inclined plane with respect to the surface of the medium (3) where the piezoelectric crystal (6) rests, and where the inclined plane of the sole (7) has a concave shape for defocalization of the ultrasonic beam (5), the piezoelectric crystal (6) being configured to adapt to said concave shape of the sole (7). (Machine-translation by Google Translate, not legally binding)
    公开号:ES2760223A1
    申请号:ES201831097
    申请日:2018-11-13
    公开日:2020-05-13
    发明作者:Maestre Iratxe Aizpurua；Casas Ivan Castro；Montejano Antonio García
    申请人:Ideko S Coop；
    IPC主号:
    专利说明:

    [0001]
    [0002]
    [0003]
    [0004] Technique sector
    [0005]
    [0006] The present invention relates to an ultrasound inspection system that is specially configured to detect discontinuities in butt welds with a single pair of ultrasound sensors, although it can be used to detect discontinuities in other types of welds.
    [0007]
    [0008] State of the art
    [0009]
    [0010] The use of ultrasonic signals in non-destructive testing (NTD) is known. One of its main applications is the detection of discontinuities in welds. For such detection, the use of inspection techniques such as “TOFD” (“Time-of-flight diffraction”), “Phased array”, AUT (“Automatic Ultrasound inspection”), or combinations of these is known .
    [0011]
    [0012] The TOFD technique is based on the interaction of ultrasonic waves with discontinuities, which causes the emission of diffracted waves at the edges, the ends of the discontinuities behaving as sound sources. The most common is to work with two ultrasound sensors, one in emission and the other in reception.
    [0013]
    [0014] Thus, a pair of ultrasound sensors is used, one of them in an emitter configuration and the other in a receiver configuration, which are arranged in contact on the surface of the medium to be inspected. The emitter sends an ultrasonic beam, or pulse, through the medium, which is received by the receiver, so that depending on the time elapsed between the emission and reception of the beam, the existence of a discontinuity in the medium can be established.
    [0015]
    [0016] The ultrasound sensors are made up of a piezoelectric crystal and a sole, or shoe, for the arrangement of the crystal. The piezoelectric crystal has a flat and circular shape and the soleplate has a straight inclined plane where it is arranged supporting the glass, so that the sensor focuses the ultrasonic beam at a specific angle that is a function of the crystal and its arrangement on the sole.
    [0017]
    [0018] To vary the angle at which the ultrasonic beam strikes and direct it towards the area of the weld to be inspected, the inclination of the support between the glass and the sole must be modified, and / or the distance between the emitter and receiver must be varied .
    [0019]
    [0020] Accordingly, when large thickness welds are required to be inspected, for example on the order of 100 mm, a single pair of ultrasonic sensors is not sufficient to cover the full thickness of the weld. Therefore, it is necessary to use several pairs of ultrasound sensors, for example, three pairs of sensors, one pair to inspect the upper part of the weld, another pair to inspect the central part and another pair to inspect the lower part. Consequently, to inspect a large thickness weld, it is required to use several ultrasound sensors, which increases the cost of the inspection system. Similarly, it implies greater mechanical complexity and difficulty to ensure the correct acquisition of the results.
    [0021]
    [0022] Therefore, an alternative solution is necessary that allows the detection of discontinuities in welds, and especially in large thickness welds, without the need to use several sensors.
    [0023]
    [0024] Object of the invention
    [0025]
    [0026] A subject of the present invention is an ultrasonic inspection system for the detection of discontinuities in welds, and especially for the detection of discontinuities in butt welds.
    [0027]
    [0028] The ultrasound inspection system includes:
    [0029]
    [0030] • an emitting ultrasound sensor configured to send an ultrasonic beam through a medium to be inspected, and
    [0031]
    [0032] • a receiving ultrasound sensor configured to receive the ultrasonic beam,
    [0033]
    [0034] or each ultrasound sensor comprising a piezoelectric crystal and a sole, the sole being available on the surface of the medium to be inspected and having the it soleplates an inclined plane with respect to the surface of the medium where the piezoelectric crystal rests.
    [0035]
    [0036] According to the invention, the inclined plane of the sole where the piezoelectric crystal rests has a concave shape for defocalization of the ultrasonic beam, the piezoelectric crystal being configured to adapt to said concave shape of the sole.
    [0037]
    [0038] Accordingly, with a single pair of ultrasound sensors, a defocalized ultrasonic beam can be obtained, so that the entire thickness of the medium to be inspected can be covered without the need to use several pairs of sensors.
    [0039]
    [0040] According to an embodiment of the invention, the concave shape of the sole is cylindrical. Said shape preferably has a radius of curvature of less than 100mm, so that defocalization of the ultrasonic beam is obtained, allowing the entire thickness of the weld to be covered. Even more preferably the radius of curvature is 20mm.
    [0041]
    [0042] According to another embodiment of the invention, the concave shape of the sole is spherical or spheroidal. Said shape preferably has first and second radii of curvature, both less than 100mm, so that detection of discontinuities in the medium is improved.
    [0043]
    [0044] Preferably the piezoelectric crystal has three zones to de-focus the ultrasonic beam according to two limit angles and a central angle; and thus be able to inspect the weld more efficiently. Thus, the piezoelectric crystal has a first zone for directing the ultrasonic beam at an upper limit angle, a second zone for directing the ultrasonic beam at a central angle, and a third zone for directing the ultrasonic beam at a lower limit angle, where the second zone is arranged between the first and third zone, the second zone having a width less than the width of the first and third zone.
    [0045]
    [0046] The piezoelectric crystal preferably has a width greater than its depth, so that detection of small discontinuities in the weld is improved.
    [0047]
    [0048] According to a preferred embodiment, the width of the second zone of the piezoelectric crystal is 1/3 of the width of the first or third zone.
    [0049] According to said preferred embodiment, the width of the piezoelectric crystal is 1.7 greater than the depth.
    [0050]
    [0051] The use of the ultrasonic inspection system for the detection of discontinuities in butt welds is also an object of the invention.
    [0052]
    [0053] Description of the figures
    [0054]
    [0055] Figure 1 shows an ultrasound inspection system according to an embodiment of the state of the art with a single pair of ultrasound sensors.
    [0056]
    [0057] Figure 2 shows an ultrasound inspection system according to another embodiment of the state of the art with three pairs of ultrasound sensors to inspect a weld of large thickness.
    [0058]
    [0059] Figure 3 shows a perspective view of an embodiment of the ultrasound inspection system of the invention with a single pair of ultrasound sensors.
    [0060]
    [0061] Figure 4 shows a perspective view of one of the ultrasound sensors of the inspection system of the previous figure.
    [0062]
    [0063] Figure 5 shows a top plan view of the glass of the ultrasound sensor of the previous figure.
    [0064]
    [0065] Figure 6 shows a schematic view of the two limit angles and the central angle of the defocalization of the ultrasonic beam.
    [0066]
    [0067] Figure 7 shows a schematic view of the ultrasound inspection system of the invention showing the defocalization of the ultrasonic beam.
    [0068]
    [0069] Figure 8 shows a perspective view of one of the ultrasonic sensors of the inspection system according to another embodiment of the invention.
    [0070]
    [0071] Figure 9 shows a perspective view of the sole of the ultrasound sensor of the exemplary embodiment of figure 4.
    [0072]
    [0073] FIG. 10 shows a perspective view of the sole of the ultrasound sensor of the embodiment of FIG. 8.
    [0074]
    [0075] Detailed description of the invention
    [0076]
    [0077] Figure 1 shows an ultrasound inspection system according to a state-of-the-art configuration to carry out an inspection according to the “TOFD” technique ( Time-of-flight diffraction '). .
    [0078]
    [0079] The inspection system comprises a pair of ultrasound sensors (1,2) that are available on a means (3) to be inspected, such as, for example, two parts between which a weld (4) is defined. Specifically, the inspection system comprises an emitting ultrasound sensor (1) that is configured to send an ultrasonic beam (5) through the medium (3) to be inspected and a receiving ultrasound sensor (2) that is configured to receive the beam. ultrasonic (5) after it has been refracted in the medium (3).
    [0080]
    [0081] The ultrasound sensors (1,2) of the inspection system shown in Figure 1 have a piezoelectric crystal (6) and a sole (7), or shoe, on which the crystal (6) is supported. The crystal (6) has a flat and circular shape and rests on a straight inclined plane of the sole (7), so that according to said embodiment of the crystal (6) and the sole (7), the ultrasonic beam ( 5) it is refracted according to a specific angle (O), and is therefore directed towards a specific area of the weld (4) of the medium (3). According to this embodiment, to focus the ultrasonic beam (5) at different angles, it is necessary to modify the inclination of the plane of the sole (7) on which the glass (6) is supported, and / or to vary the distance (PCS ) between the emission and reception of the ultrasonic beam (5) when the beam (5) passes from the sole (7) to the medium (3) and vice versa.
    [0082]
    [0083] In figure 2 another ultrasound inspection system according to another configuration of the state of the art is shown to also apply an inspection according to the "TOFD" technique in a weld (4) of a large thickness.
    [0084]
    [0085] In this case, in order to cover the entire thickness of the weld (4) it is necessary to use a inspection system with three pairs of ultrasound sensors (1.1,1.2,1.3,2.1,2.2,2.3), which have the same glass configuration (6) and sole (7) as the ultrasound sensors (1,2) of the inspection system shown in figure 1.
    [0086]
    [0087] The first pair of sensors (1.1,2.1) sends a first ultrasonic beam (5.1), according to a first angle (P), to inspect the upper part of the weld (4), the second pair of sensors (2.1,2.2) sends a second ultrasonic beam (5.2), according to a second angle (a), to inspect the central part of the weld (4), and the third pair of sensors (2.1.2.2) send a third ultrasonic beam (5.3), according to a third angle ( y ), to inspect the bottom of the weld (4).
    [0088]
    [0089] The invention proposes to use a single pair of ultrasound sensors (1,2) that emits a single de-focused ultrasound beam (5) with which the entire thickness of the weld (4) can be inspected.
    [0090]
    [0091] Next, the ultrasound inspection system of the invention is described, where the same references are used as those used in Figures 1 and 2 to refer to similar elements.
    [0092]
    [0093] The inspection system comprises an emitting ultrasound sensor (1) configured to send an ultrasonic beam (5) through the medium (3) to be inspected and a receiving ultrasound sensor (2) configured to receive the ultrasonic beam (5). Ultrasonic sensors (1,2) are available on the surface of the medium (3) to be inspected according to a position facing each other, with a sensor arranged on each side of the weld (4), as shown in the figure 3.
    [0094]
    [0095] As shown in the exemplary embodiment of figure 4, each ultrasound sensor (1.2) has a piezoelectric crystal (6) and a sole (7). The sole (7) is available on the surface of the medium (3) to be inspected, and has an inclined plane in its upper part where the piezoelectric glass (6) rests, so that said inclined plane of the sole (7), and therefore the glass (6), are arranged according to an inclined position with respect to the surface of the medium (3).
    [0096]
    [0097] The inclined plane has a concave shape, and the glass (6) has at least one part that adapts to the concave shape, so that the arrangement of the glass (6) on the sole (7) according to Said concave shape allows to defocalize the ultrasonic beam (5). In figure 4 it is shown that the lower part of the glass (6) has a reciprocal shape to the inclined plane of the sole (7).
    [0098]
    [0099] The piezoelectric crystal (6) has three zones (6.1,6.2, 6.3) to de-focus the ultrasonic beam (5) according to two upper and lower limit angles and a central angle (P, a, y).
    [0100]
    [0101] The first zone (6.1) of the crystal (6) directs the ultrasonic beam (5), according to an upper limit angle (P), towards the upper part of the weld (4), the second zone (6.2) directs the ultrasonic beam ( 5), at a central angle (a), towards the central part of the weld (4), and the third zone directs the ultrasonic beam, at a lower limit angle (y), towards the bottom of the weld (4) . Thus, as shown in the schematic view of figure 7, the ultrasound inspection system allows the ultrasound beam (5) to be defocused to inspect the entire thickness of the weld (4).
    [0102]
    [0103] The second zone (6.2) of the piezoelectric crystal (6) is arranged between the first (6.1) and the third zone (6.3), the width (W2) of the second zone (6.2) must be less than the width (W1, W3 ) of the first (6.1) and third zone (6.3) to be able to de-focus the ultrasonic beam (5) according to the angles (P, a, and).
    [0104]
    [0105] Preferably, as seen in Figures 4 and 5, the piezoelectric crystal (6) has a rectangular "H" shape configuration with two major sides and two minor sides, where the width (W) of the crystal (6) ) decreases progressively from one of its major sides to the center of the glass (6), and from said center the width (W) gradually increases until it reaches the other largest side of the glass (6). Thus, at least on its minor sides, the glass (6) has a concave shape.
    [0106]
    [0107] An example of the angles (P, a, and) at which the defocusing of the ultrasonic beam (5) is defined in order to inspect the entire thickness of the weld (4) is shown in the schematic view of figure 6. The angles are referenced with respect to the vertical, the vertical being parallel to the weld (4).
    [0108]
    [0109] The first area (6.1) of the glass (6) allows the ultrasound beam (5) to be directed towards the top of the weld (4). Due to defocusing, the upper limit angle (P) of the beam (5) in that area is high, specifically for a weld (4) with a thickness of 100 mm, the angle (P) is approximately 70 °. Although the distance the beam must travel (5) to go towards the top of the weld (4) is short, since the greater the refracted angle the greater the acoustic pressure required, it is necessary to increase the width (W1) of the first zone (6.1) to achieve the energy needed to achieve the weld (4).
    [0110]
    [0111] The third zone (6.3) allows the ultrasound beam (5) to be directed towards the bottom of the weld (4). The lower limit angle ( y ) due to defocusing in this area is low, specifically for a weld (4) with a thickness of 100 mm, the angle ( y ) is approximately 20 °, however, since the distance it must traverse the beam (5) to go towards the bottom of the weld (4) is high, it is also necessary to increase the width (W3) of the third zone (6.3) to achieve the necessary acoustic pressure.
    [0112]
    [0113] The second zone (6.2) allows the ultrasound beam (5) to be directed towards the central part of the weld (4). For a weld (4) with a thickness of 100 mm the refracted angle (a) in this area is approximately 40 °. Since the second zone (6.2) obtains sound pressure from the first (6.1) and third zone (6.3), and in order not to excessively focus the beam (5) in the central part of the weld (4), it is necessary to reduce the width (W2) of the glass in the second zone (6.2) with respect to the width of the other zones (6.1,6.3)
    [0114]
    [0115] Taking into account that the weld to be inspected is of considerable thickness (up to 100mm), as seen in figure 7, the ultrasound sensors (1,2) are arranged facing each other with a separation distance (PCS) of approximately 70mm between the emission and reception of the ultrasonic beam (5), although at smaller distances the inspection system correctly detects discontinuities in the weld (4).
    [0116]
    [0117] In order to correctly detect small discontinuities of the order of 1.5-2mm, it is necessary for the glass (6) to have a width (W) greater than its depth (D), since if the depth (D) is increased, the Ultrasonic beam width (5), which would make it difficult to detect small discontinuities. That is, as the depth (D) increases, the signals generated by the diffraction of the beam at the top and bottom of the discontinuity would overlap, making it impossible to discern one another when the signals are represented on the screen.
    [0118]
    [0119] According to the exemplary embodiment shown in Figures 4 and 5, preferably the width (W2) of the second zone (6.2) of the glass (6) is approximately 1/3 of the width (W1, W3) of the first (6.1) or of the third zone (6.3), the width of the first and equal third zones.
    [0120]
    [0121] Also according to said exemplary embodiment, the width (W) of the piezoelectric crystal (6) is approximately 1.7 greater than the depth (D).
    [0122]
    [0123] Figures 4 and 9 show an example of embodiment of the sole (7) where the inclined plane to support the piezoelectric crystal (6) has a cylindrical concave shape. Said shape has a radius of curvature (R1) of less than 100 mm and preferably of 20 mm. The radius of curvature (R1) is arranged parallel to the smaller sides of the piezoelectric crystal (6).
    [0124]
    [0125] Figures 8 and 10 show another example of embodiment of the sole (7) in which the inclined plane for the support of the piezoelectric crystal (6) has a concave spherical or spheroidal shape. Said shape has first and second radii of curvature (R1, R2), both radii being less than 100 mm.
    [0126]
    [0127] The first radius of curvature (R1) is arranged parallel to the smaller sides of the piezoelectric crystal (6) while the second radius of curvature (R1) is arranged parallel to the larger sides of the piezoelectric crystal (6).
    [0128]
    [0129] In both embodiments, the glass has a reciprocal shape, at least in its lower part, to adapt to the inclined plane of the sole (7).
    权利要求:
    Claims (13)
    [1]
    1 Ultrasonic inspection system comprising:
    • an emitting ultrasound sensor (1) configured to send an ultrasonic beam (5) through a medium (3) to be inspected, and
    • a receiving ultrasound sensor (2) configured to receive the ultrasonic beam (5),
    or each ultrasound sensor (1,2) comprising a piezoelectric crystal (6) and a sole (7), the sole (7) being available on the surface of the medium (3) to be inspected, and the sole (7) having a inclined plane with respect to the medium surface (3) where the piezoelectric crystal (6) rests,
    characterized by:
    the inclined plane of the sole (7) where the piezoelectric crystal (6) rests has a concave shape for de-focalization of the ultrasonic beam (5), the piezoelectric crystal (6) being configured to adapt to said concave shape of the sole ( 7).
    [2]
    2. - Ultrasonic inspection system, according to the preceding claim, characterized in that the concave shape of the sole (7) is cylindrical.
    [3]
    3. - Ultrasonic inspection system, according to the preceding claim, characterized in that the cylindrical concave shape has a radius of curvature (R1) of less than 100mm.
    [4]
    4. - Ultrasonic inspection system, according to the preceding claim, characterized in that the radius of curvature (R1) is 20mm.
    [5]
    5. - Ultrasonic inspection system, according to claim 1, characterized in that the concave shape of the sole (7) is spherical or spheroidal.
    [6]
    6. - Ultrasonic inspection system, according to the previous claim, characterized in that the spherical or spheroidal concave shape has first and second radii of curvature (R1, R2), both less than 100mm.
    [7]
    7. - Ultrasonic inspection system, according to any one of the preceding claims, characterized in that the piezoelectric crystal (6) has:
    • a first zone (6.1) to direct the ultrasonic beam (5) according to an upper limit angle (P),
    • a second zone (6.2) to direct the ultrasonic beam (5) according to a central angle (a), and • a third zone (6.3) to direct the ultrasonic beam (5) according to a lower limit angle ( y ),
    wherein the second zone (6.2) is arranged between the first (6.1) and the third zone (6.3), the second zone (6.2) having a width (W2) less than the width (W1, W3) of the first (6.1 ) and third zones (6.3).
    [8]
    8. - Ultrasonic inspection system, according to the preceding claim, characterized in that the width (W2) of the second zone (6.2) is 1/3 of the width (W1, W3) of the first (6.1) or third zone (6.3).
    [9]
    9. - Ultrasonic inspection system, according to any one of the preceding claims, characterized in that the piezoelectric crystal (6) has a rectangular configuration in the shape of an "H".
    [10]
    10. - Ultrasonic inspection system, according to any one of the preceding claims, characterized in that the piezoelectric crystal (6) has a width (W) greater than its depth (D).
    [11]
    11. - Ultrasonic inspection system, according to the preceding claim, characterized in that the width (W) of the piezoelectric crystal (6) is 1.7 greater than the depth (D).
    [12]
    12. - Ultrasonic inspection system, according to any one of the preceding claims, characterized in that the ultrasound sensors (1,2) are available on the surface of the medium (3) to be inspected with a separation of 70 mm between the emission and reception of the ultrasonic beam (5).
    [13]
    13. - Use of the ultrasound inspection system of any one of the preceding claims for the detection of discontinuities in butt welds.
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    同族专利:
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    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US4435984A|1980-04-21|1984-03-13|Southwest Research Institute|Ultrasonic multiple-beam technique for detecting cracks in bimetallic or coarse-grained materials|
    JPS58178252A|1982-04-14|1983-10-19|Nippon Kokan Kk <Nkk>|Ultrasonic probe|
    CN203606326U|2013-10-08|2014-05-21|国家电网公司|Ultrasonic probe|
    US20170074831A1|2015-09-11|2017-03-16|Olympus Scientific Solutions Americas Inc.|Focusing wedge for ultrasonic testing|
    US20180277266A1|2015-12-18|2018-09-27|Electricite De France|Device For Controlling And Measuring Welding Defects On A Cylindrical Wall And Method Implementing Same|
    GB978183A|1963-06-28|1964-12-16|Zeiss Jena Veb Carl|Improvements in or relating to sound transducers for nondestructive testing of materials and ultrasonic diagnosis|
    FR3011332B1|2013-09-30|2019-12-20|Areva Np|METHOD AND DEVICE FOR NON-DESTRUCTIVE TESTING OF A WELDING OF A NUCLEAR REACTOR PART|
    法律状态:
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    优先权:
    申请号 | 申请日 | 专利标题
    ES201831097A|ES2760223B2|2018-11-13|2018-11-13|ULTRASONIC INSPECTION SYSTEM|ES201831097A| ES2760223B2|2018-11-13|2018-11-13|ULTRASONIC INSPECTION SYSTEM|
    EP19382725.0A| EP3654031A1|2018-11-13|2019-08-26|Ultrasonic inspection system|
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