Probe wedge and ultrasonic testing equipment

Abstract

The aim is to improve the accuracy of ultrasonic testing by suppressing noise generation in probe wedges and ultrasonic testing equipment. [Solution] In a probe wedge 13C attached to the probe 12C of the probe 11C, the probe comprises a wedge body 81 having a block shape with a transmitting unit 12a and a receiving unit 12b provided independently, an installation surface 82 provided on the wedge body, an installation surface 83 provided on the opposite side of the wedge body from the installation surface and to which the probe can be attached, a through hole 84 provided along a through-direction penetrating from the installation surface to the installation surface and into which a gel material can be filled, and a separating plate 85 arranged along the radial and axial directions of the through hole to separate the through hole into the transmitting unit side and the receiving unit side, wherein the separating plate has a first separating plate 85A arranged on the installation surface side and a second separating plate 85B arranged on the installation surface side and made of a softer material than the first separating plate.

Description

Technical Field

[0001] The present disclosure relates to a wedge for a probe and an ultrasonic inspection device.

Background Art

[0002] In ultrasonic inspection in the industrial field, as a contact medium, glycerin paste, machine oil, or water is applied to the outer surface of a structure so that ultrasonic waves propagate into the interior of the structure to be inspected, and an ultrasonic probe (hereinafter referred to as a probe) is pressed against it to transmit and receive ultrasonic waves. In order to propagate ultrasonic waves with directivity in a desired direction within the test object, as an internal structure of the probe, it has a wedge (also called a wedge or a shoe) to which a piezoelectric vibrator is attached, or a wedge is attached to the outside of a vertical probe and used. In the former case, the structure including the piezoelectric element and the wedge are not separated, and in the latter case, the structure including the piezoelectric element (vertical probe) and the wedge are separated. Hereinafter, when only "probe" is described without particular notice, it is assumed to include a wedge as a part of the probe. Also, in the present disclosure, when describing "vertical probe" or "vertical two-vibrator probe", which are types of probes, it is described as not including a wedge and being used with a wedge attached. Similarly, when describing "oblique-angle probe", which is a type of probe, it necessarily includes a wedge due to the characteristics of the probe. For other types of probes, for example, when describing "two-vibrator probe" or "array probe", it will be explained as necessary whether it includes a wedge or not.

[0003] When ultrasonic waves are propagated at an oblique angle to the normal to the outer surface of a structure, wedges are often manufactured by machining resin, taking into account Snell's Law, which describes the relationship between the sound velocity between the structure and the wedge, and the angle of incidence and the angle of refraction at the boundary between the wedge and the structure. If the outer surface of the object to be inspected has a large curvature, regardless of whether manual or automated flaw detection is performed, the contact surface of the wedge is processed to conform to the shape of the outer surface of the object in order to improve contact with the outer surface (securing contact area) and maintain the probe's position (suppressing wobbling when pressed). In particular, when performing automated flaw detection, the contact and stability of the probe pressed against the object are required.

[0004] Therefore, as an alternative to the direct contact method, which involves directly pressing the probe against the object using a solid wedge, methods such as the immersion method and the water column method, which use liquid, are known to improve the contact of the probe with the outer surface of the object. Using liquid improves contact by conforming to the outer surface of an uneven structure, but the liquid must be kept in place without gas contamination between the vertical probe and the object. The equipment becomes larger due to the use of a water tank and water flow generation mechanism, making on-site implementation difficult.

[0005] To maintain a deformable medium between the vertical transducer and the subject without increasing the size of the apparatus, methods using elastic membranes or bags such as gels or rubber are available. Methods using gels include using konjac as the gel, using gelling agents such as agar or gelatin at several times the amount added to food products, and using specialized products such as hydrophilic / hydrophobic segmented polyurethane gel (SPUG). When using gel as a wedge, it can be used either by cutting it after gelling, or by pouring it in before gelling and waiting for it to gel. Methods using membranes or bags involve filling the bag with water or oil. While the latter method is useful, it requires a structure to prevent liquid leakage, and if the bag ruptures, reassembly and cleaning are necessary.

[0006] The technology disclosed herein relates to a relatively small gel wedge that can be handled in the same way as a conventional wedge and reduces the effort required in case of breakage. When a gel wedge is used with gel alone, its shape changes, and the time it takes for ultrasound to propagate through the gel varies depending on how it is pressed. Therefore, it is assumed that the wedge is made of a structural material (solid) that can maintain the shape of the gel at a generally constant level. In other words, the structural material is used to suppress large shape changes caused by pressing, and resins such as acrylic and polyimide are commonly used, but the material of the structural material is not limited to resin, and metals can also be used as long as they are solid.

[0007] For the sake of explanation, the following description will primarily focus on metal structures with curvature, such as pipe welds, as the main targets for ultrasonic inspection, but this does not limit the types or materials of the objects being inspected. Furthermore, in addition to being used as a probe held by a person for inspection, the gel wedge is also suitable as a probe for automated ultrasonic inspection using scanners or robots, due to its excellent adhesion to the outer surface of structures and its stability. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Patent No. 5725901 [Patent Document 2] Japanese Patent Publication No. 2006-90804 [Patent Document 3] Patent No. 6362568 [Overview of the project] [Problems that the invention aims to solve]

[0009] When a vertical probe is attached to a gel wedge composed of gel and non-gel structural materials to inspect a specimen for defects, the following four technical challenges arise. Technical challenge a. Due to the different acoustic impedances of the gel, structural material, and subject, ultrasound reflected at the boundaries between these materials becomes relatively strong noise near the surface of the subject. Technical challenge b. The difference in acoustic impedance between the wedge and the gel is smaller than the difference in acoustic impedance between the sample material (mainly metal) that should be propagated and the gel. As a result, reflected waves that pass from the gel to the wedge and return to the vertical probe appear in the area to be inspected, creating noise and reducing the detection performance (S / N ratio) for minute defects compared to conventional solid wedges. Technical challenge c. When a liquid such as glycerin paste is filled into the gel to improve contact between the vertical probe and the gel, and the vertical probe is pressed against the gel, the gel in that area indents by the volume of the liquid, while the gel on the contact surface bulges, causing a change in shape. This indentation and bulging of the gel not only negatively affects the probe's contact and stability with the sample, which is its intended purpose, but the amount of liquid can also become a factor in variability in detection when the probe assembly and inspection work is repeated over a long period of time. Technical issue d. When using a gel wedge with a transceiver-separated dual-element transducer, the deformation of the gel portion when the transducer is pressed against the sample is greater than that of a solid wedge. Therefore, if a material such as cork is used, it may not conform to the shape of the sample surface, leading to breakage and potentially making it impossible to maintain inspection performance. The main reasons for using a dual-element transducer are to suppress dead zones and detect defects near the surface, or, when it is necessary to use a thin wedge due to surrounding structures, to suppress strong noise caused by multiple reflections within the wedge that result from making it thin. The inventors focused primarily on these four issues and made improvements to the structure of the gel wedge.

[0010] Figures 1 and 2 show the structure when a conventionally used resin wedge is replaced with a gel wedge. Figure 1 is a schematic diagram representing a gel wedge for a vertical probe, and Figure 2 is a schematic diagram representing a gel wedge for an angled probe. In Figures 1 and 2, (a) represents a general wedge, and (b) represents a general gel wedge. For simplicity, a single-type probe consisting of one piezoelectric element is used as an example here, but dual-element probes and array probes consisting of multiple piezoelectric elements are also covered. The reason for using a wedge in an array probe is that although the incident angle of ultrasound can be electronically scanned by delay control even without a wedge, using a wedge increases the effective aperture and improves sensitivity in the angled direction. In addition, when scanning an array probe without a wedge in direct contact with the subject, there is a concern about performance degradation due to wear of the matching layer (also called the protective plate that forms the contact surface of the probe), so a wedge may be used to protect against wear. Additionally, when arraying the transducers increases the contact surface area, leading to strong adsorption due to atmospheric pressure and making detachment difficult, wedges may be used to avoid performance degradation due to delamination of the matching layer.

[0011] As shown in Figures 1 and 2, these wedge-type probes consist of a general-purpose vertical probe and a wedge section, and the vertical probe and wedge section are often joined by screws. The figures show a case where an L-shaped bracket is attached to the probe casing and a helicoil is inserted into the wedge for connection, but in some cases the vertical probe casing and wedge are equipped with screw grooves that allow the casing itself to be screwed into the wedge for connection. In addition, water, oil, or a special glycerin paste is applied to the boundary between the vertical probe section and the wedge section to prevent obstruction of ultrasonic wave propagation by gas (air or bubbles).

[0012] In the vertical probes used for vertical flaw detection and plate thickness measurement shown in Figure 1, there are cases where only the vertical probe portion is in direct contact. However, especially when high precision is required for thickness measurement, a flat wedge without inclination may be used. The flat wedge is often referred to as a delay material.

[0013] In the angle beam probe used in angle beam flaw detection shown in Figure 2, the wedge portion is molded so that the vertical probe can be tilted at a certain angle relative to the mounting surface. When these are made into gel wedges, simply considering the directivity of ultrasound, the area of ​​the piezoelectric element, or a wider area along the ultrasound propagation path, is replaced with gel. Here, replacement means hollowing out a part of a typical solid wedge and filling it with gel. The solid portion used for filling with gel will be called the structural material. Without the structural material, the angle at which ultrasound enters the object will naturally become unstable, making it impossible to refract the ultrasound at the desired angle and inspect the inside of the object. The structural material is molded considering stability when in contact with the object, such as a pipe.

[0014] Prior art includes Patent Documents 1 to 3. When using Patent Document 1, the thickness of the gel protrusion (elastic protrusion 32 in Patent Document 1) from the contact surface of the jig body (structural material in this description) causes scattered and reflected waves generated at the other end face 22a, the corner of the opening 23a on one side, and the gap with the object to be examined, resulting in noise corresponding to the aforementioned technical problem a. Furthermore, reflected waves from one end face 21a of the shoe 20, and from these corners, will generate noise corresponding to technical problem b. Moreover, when automatically inspecting the cylindrical outer surface with the probe of Patent Document 1, a separate mechanism is required to maintain the probe's orientation.

[0015] As a countermeasure to the technical problem b shown in Patent Document 2, it is known that sound-absorbing materials commonly used include rubber, which has high attenuation due to absorption and conversion to heat, and a structure with a jagged shape that increases scattering attenuation. Although there is no problem with providing such a structure, the structure of the structural material becomes complex.

[0016] Patent Document 3 describes a device in which the wedge portion is made of a solid material such as resin, and the acoustic separation plate (acoustic shielding plate 5 in Patent Document 3) is made of cork, with the cork sandwiched between two wedges for transmitting and receiving and fixed with adhesive. If this is replaced with gel, as mentioned above, the cork will not be able to adequately follow the shape changes of the gel, resulting in reduced durability. For example, damage to the cork portion may cause cork fragments to get caught during flaw detection scanning, potentially reducing detection performance and requiring rework.

[0017] Although not mentioned in any of the Patent Documents 1-3, a common technical issue c for gel wedges is that the coupling medium (glycerin paste, water, oil, etc.) filling the space between the vertical transducer and the wedge must not be completely sealed. If there is too much coupling medium, it will push the gel towards the contact surface, causing it to protrude and making it difficult to maintain stable contact. Also, as the gel wedge attached to the vertical transducer is repeatedly pressed against and released from the test subject, the coupling medium may gradually seep out from the not-completely sealed boundary, reducing the amount of protrusion and potentially altering the contact during the test, thus affecting sensitivity. Furthermore, if the gel breathes by expanding and contracting, conversely, if it draws in air, forming an air layer at the contact point between the gel and the transducer, this can significantly reduce sensitivity.

[0018] This disclosure and Patent Documents 1-3 envision manual or automated unintended tubing (UT) being performed on a subject with curvature using a transducer with improved contactability and stability. In particular, the content of creating a gel with a variable shape by drilling holes in a part of the transducer wedge is identical.

[0019] Figure 3 is an explanatory diagram showing the propagation path of ultrasound through the wedge and the subject when the transducer is pressed against the subject, and Figure 4 is a graph showing the waveform intensity as a function of path length.

[0020] As shown in FIGS. 3 and 4, when performing angle beam flaw detection using the gel wedge shown in Patent Document 1 or a commercially available gel wedge, as shown in FIG. 4 with the waveform in the detection mode further simplified, a waveform including noise caused by Technical Problem a and Technical Problem b will be obtained. Therefore, when the defect is near the surface layer or when the defect is small and the reflected wave is weak, the signal and noise may overlap and the defect detectability may decrease.

[0021] The inventors found that among the through-hole portion provided as the ultrasonic propagation path of the gel wedge and the contact portion between the gel wedge and the test piece, the noise is in the structural material portion located in the ultrasonic propagation direction (corresponding to the corner portion of the one-side opening 23a in Patent Document 1 / Technical Problem a), which is the wave reflected once or multiple times in the gap with the contact portion with the test piece and received, and also the ultrasonic wave reflected at the gel and test piece boundary propagates in the structural material and is the wave reflected and received at the outer surface of the structural material (corresponding to the side surface portion where the sound-absorbing material is attached in FIG. 8 of Patent Document 2 / Technical Problem b).

[0022] As a result of examining a gel wedge that can exclude these technical problems, it was found that by utilizing the fact that the sound velocity of the examined gel is close to the sound velocity of liquids such as water and oil and slower than the sound velocity of the material that is the main test piece, and by replacing the structural material portion on the propagation direction side with gel as the structural material shape of the angle beam flaw detection gel wedge, Technical Problems a to c can be solved at once. That is, if the structural material portion on the propagation direction side is replaced with gel, for Technical Problem a, the reflection source itself that becomes noise can be removed. For Technical Problem b, since the gel sound velocity is 70% or less of the structural material sound velocity, by propagating in the gel region for a long time, the noise appearance region can be adjusted to be outside the attention region for capturing the signal. For Technical Problem c, since it becomes a structure that can escape the deformation of the gel surface on the side that has no effect on the flaw detection performance by replacing up to the side surface of the structural material with gel, the deformation of the gel located on the side in contact with the vertical probe that affects the flaw detection performance and the gel located on the side in contact with the test piece is suppressed, and the contact property and sensitivity are stabilized.

[0023] That is, instead of the hole along the ultrasonic propagation region like the structural material part of the gel wedge shown in the patent document, a wedge having a structure in which the structural material part located in the direction that becomes a noise factor in addition to the propagation region is replaced with gel not only suppresses noise, but also can obtain the effect of ensuring contact and stability and suppressing variations in detection performance.

[0024] Also, a wedge in which a part of the structural material located in the ultrasonic propagation direction is replaced with gel has a "U" shape when viewed from the contact surface direction. When gripping the side surfaces located at the upper and lower parts of the "U" of the "U" with the hand or a jig during manual flaw detection or automatic flaw detection, there is a risk of deformation because the structural material strength is lower than before. In order to suppress deformation, a structure having a beam (reinforcing material) inside the gel may be provided.

[0025] Also, when the ultrasonic wave reflects in the gel and reaches the beam and the reflected wave from the beam is received again to become noise, by having a beam shape in which the ultrasonic wave is likely to scatter in all directions or deliberately having a beam structure that is not orthogonal to the propagation direction, the effect of suppressing the deformation of the gel due to an external force and the effect of suppressing noise can be obtained.

[0026] Also, since the reflected wave from the beam can predict the appearance position, by actively capturing and evaluating it, it is possible to determine whether the deformation following the surface structure of the specimen is maintained. That is, when constructing an automatic ultrasonic inspection system, a gate is provided in the region where the reflected wave from the beam appears, and by measuring and evaluating the position and intensity of the reflected wave, it is possible to estimate the contact and stability during the probe scanning, such as whether the gel shape following the surface structure of the specimen is maintained.

[0027] The present disclosure solves the above-described problems, and an object thereof is to provide a wedge for a probe and an ultrasonic inspection device that improve ultrasonic inspection accuracy by suppressing the generation of noise.

Means for Solving the Problems

[0028] To achieve the above objective, the probe wedge of the present disclosure is a probe wedge attached to the probe of a probe, wherein the probe comprises a wedge body having a block shape and having a transmitting unit and a receiving unit independently provided, a mounting surface provided on the wedge body, a mounting surface provided on the wedge body opposite to the mounting surface and to which the probe can be attached, a through hole provided along a through direction penetrating from the mounting surface toward the mounting surface and into which a gel material can be filled, and a separating plate arranged along the radial and axial directions of the through hole to separate the through hole into the transmitting unit side and the receiving unit side, wherein the separating plate comprises a first separating plate arranged on the mounting surface side and a second separating plate arranged on the mounting surface side and formed of a material softer than the first separating plate.

[0029] Furthermore, the ultrasonic inspection apparatus of this disclosure comprises a vertical dual transducer probe having a transmitting unit and a receiving unit, a wedge for the dual transducer probe attached to the vertical dual transducer probe, and a flaw detector connected to the vertical dual transducer probe. [Effects of the Invention]

[0030] The probe wedge and ultrasonic inspection apparatus of this disclosure can improve the accuracy of ultrasonic inspection by suppressing the generation of noise. [Brief explanation of the drawing]

[0031] [Figure 1] Figure 1 is a schematic diagram representing a gel wedge for a vertical probe. [Figure 2] Figure 2 is a schematic diagram representing a gel wedge for an angle beam probe. [Figure 3] Figure 3 is an explanatory diagram showing the path through which ultrasound propagates inside the wedge and the subject. [Figure 4] Figure 4 is a graph showing the waveform intensity as a function of path length. [Figure 5] Figure 5 is a schematic diagram showing the external appearance of the vertical probe used in the first embodiment. [Figure 6]Figure 6 is a schematic diagram illustrating the noise factors and definition of the inspection direction for gel wedges in angled flaw detection. [Figure 7] Figure 7 is a schematic diagram representing the wedge of the first embodiment. [Figure 8] Figure 8 is a schematic diagram showing a modified example of the wedge according to the first embodiment. [Figure 9] Figure 9 is a schematic diagram illustrating the operation of the wedge according to the first embodiment. [Figure 10] Figure 10 is a schematic diagram showing an example of an examination result obtained using an ultrasound examination device. [Figure 11] Figure 11 is a schematic diagram representing the wedge of the second embodiment. [Figure 12] Figure 12 is a schematic diagram representing the wedge of the third embodiment. [Figure 13] Figure 13 is a simplified block diagram representing the ultrasound inspection system of the fourth embodiment. [Figure 14] Figure 14 is a flowchart illustrating the ultrasound examination method. [Figure 15] Figure 15 is a cross-sectional view showing the wedge of the fifth embodiment. [Figure 16] Figure 16 is a front view showing the wedge of the fifth embodiment. [Figure 17] Figure 17 is a plan view showing the wedge of the fifth embodiment. [Figure 18] Figure 18 is a front view showing a first modified example of the wedge according to the fifth embodiment. [Figure 19] Figure 19 is a plan view showing a first modified example of the wedge according to the fifth embodiment. [Figure 20] Figure 20 is a front view showing a second modified example of the wedge according to the fifth embodiment. [Figure 21] Figure 21 is a plan view showing a second modified example of the wedge according to the fifth embodiment. [Figure 22] Figure 22 is a front view showing a third modified example of the wedge according to the fifth embodiment. [Modes for carrying out the invention]

[0032] Preferred embodiments of the present disclosure will be described in detail below with reference to the drawings. However, these embodiments do not limit the present disclosure, and where there are multiple embodiments, they may be combinations of these embodiments. Furthermore, the components in the embodiments include those readily conceivable by those skilled in the art, those that are substantially identical, and those that are equivalent.

[0033] [First Embodiment] Figure 5 is a schematic diagram showing the external appearance of the probe used in the first embodiment.

[0034] The gel wedge of the first embodiment is generally used by attaching it to a vertical probe. The gel wedge is provided with screw holes to match the vertical probe, either the type with screw holes in the housing portion of the probe as shown in Figure 5(a), or the type with screw threads on the probe as shown in Figure 5(b). In the wedge of the first embodiment, unless otherwise specified, the gel wedge shall be attached to the vertical probe using either method.

[0035] Figure 6 is a schematic diagram illustrating the noise factors and definition of the inspection direction for gel wedges in angled flaw detection.

[0036] The noise factors for the two technical challenges a and b will be explained. As shown in Figure 6, the ultrasonic waves emitted from the vertical probe propagate directionally through the gel, refract at the boundary between the gel and the specimen according to Snell's law, and propagate within the specimen. Depending on the transducer diameter, frequency, and material sound velocity, the waves propagate as plane waves within the near-field limit distance and as spherical waves beyond that distance. The noise in technical challenge a is caused by the fact that while the ultrasonic waves propagate directionally through the gel and specimen, they also have a certain degree of spread. In the structure of a conventional gel wedge, the ultrasonic waves scatter particularly at the triple point where the structural material, specimen, and gel overlap in the direction of inspection, and propagate again within the gel, resulting in noise that inevitably appears near the surface of the specimen.

[0037] The noise caused by technical challenge b is generated when longitudinal ultrasonic waves, reflected from the surface of the specimen, enter the side of the gel-filled through-hole, propagate within the structural material, split into longitudinal and transverse waves, reflect one or more times within the structural material, and return to the vertical probe. This noise appears depending on the size and shape of the wedge.

[0038] Therefore, in the first embodiment, the structural material is formed into a "U" shape, and the gel is filled to the side that is in the direction of ultrasonic wave propagation. With this configuration, the first embodiment can not only suppress the noise generated by technical problems a and b explained using Figure 6, but also stabilize the contact and sensitivity by allowing the gel surface on the side, which is less likely to affect the flaw detection performance, to deform.

[0039] Furthermore, when inspecting objects with curvature on their outer surface, such as pipes, it is preferable to create a contact surface structure with legs at the four corners, rather than making large contact with the structural material at the contact surface, so that the curvature is greater than that of the outer diameter curvature of the pipe being inspected. By using such a structural material, it is possible to stabilize the distance over which the ultrasound propagates within the gel and the angle at which it enters the object. In addition, by pressing the solid legs 21a, rather than the gel material portion, against the object 100 being inspected, the posture is stabilized, improving positioning accuracy, and the durability of the gel material can be improved by suppressing strong force being applied directly to the gel material.

[0040] <Ultrasound examination equipment> Figure 7 is a schematic diagram representing the wedge of the first embodiment. Figure 7 shows a front view of the wedge with a vertical flaw detector (dotted line) attached to the center, a top view of the wedge at the top, a bottom view of the wedge at the bottom, a left side view of the wedge on the left, and a right side view of the wedge on the right.

[0041] The ultrasonic inspection device 10 is equipped with a probe 11 and is used in connection with a flaw detector that includes an input / output unit, a control processing unit, a transmitting / receiving unit (pulsar receiver), etc. Here, the flaw detector refers to a portable flaw detector in which the pulsar receiver and a PC and user interface that control the pulsar receiver are integrated, but the PC function and the pulsar receiver function may be separate. In this embodiment, the probe 11 is a distinctive feature, so the flaw detector is omitted from Figure 7. The probe 11 is pressed against the object to be inspected, and ultrasonic waves are transmitted and received to detect defects in the object to be inspected.

[0042] The probe 11 includes a vertical probe 12 and a wedge 13.

[0043] <Wedge for probe> The wedge (wedge for probe) 13 comprises a wedge body 21, an installation surface 22, a mounting surface 23, a through hole 24, and an open portion 25.

[0044] The wedge body 21 has a block shape. The wedge body 21 is made of, for example, a resin material, but is not limited to a resin material. Here, the overall length direction of the wedge body 21 (left-right direction in the front view in the center of Figure 7) is described as the Y direction, the width direction of the wedge body 21 (up-down direction in the top view at the top of Figure 7) is described as the X direction, and the overall height direction of the wedge body 21 (up-down direction in the front view in the center of Figure 7) is described as the Z direction.

[0045] The mounting surface 22 is provided on the lower surface of the wedge body 21, that is, on one side of the wedge body 21 in the Z direction (downward in the front view in the center of Figure 7). The mounting surface 22 is preferably flat, but if pressing against a concave surface such as the inner surface of a pipe is anticipated, the gel portion may be convex to match the inspection surface of the object to be inspected. The mounting surface 23 is provided on the upper surface of the wedge body 21, that is, on the other side of the wedge body 21 in the Z direction (upward in the front view in the center of Figure 7). The mounting surface 23 is the surface for attaching the vertical probe 12. The mounting surface 23 is provided on the opposite side of the wedge body 21 from the mounting surface 22. The mounting surface 23 is inclined with respect to the mounting surface 22. That is, the wedge body 21 has the mounting surface 22 on the lower side and the upper surface 31 parallel to the mounting surface 22 on the upper side. The mounting surface 23 is provided on one side in the Y direction (to the right in the front view in the center of Figure 7) relative to the upper surface 31, and has a predetermined inclination angle with respect to the upper surface 31.

[0046] The wedge body 21 has an end face 32 on one side in the Y direction (to the right in the front view in the center of Figure 7), a side face 33 on one side in the X direction (downward in the top view at the top of Figure 7), and a side face 34 on the other side in the X direction (upward in the top view at the top of Figure 7). The mounting surface 23 is positioned between the top surface 31 and the end face 32. The mounting surface 23 slopes downward (towards the mounting surface 22) from the top surface 31 towards the end face 32.

[0047] The through-hole 24 is a circular hole that penetrates from the mounting surface 23 to the installation surface 22. The through-hole 24 is provided along an axis O1 that runs perpendicular to the mounting surface 23 and through to the installation surface 22. The axis O1 is perpendicular to the mounting surface 23 but inclined with respect to the installation surface 22. The through-hole 24 can be filled with gel material. Since the gel material is often a solid such as resin as the wedge material, the attenuation of the ultrasound is greater than that of the wedge body 21, and the propagation speed of the ultrasound is slower than that of the wedge body 21.

[0048] The opening 25 opens from the through hole 24 toward the front end face 35 in the through direction. The wedge body 21 has an end face 35 on the other side in the Y direction (to the left in the front view in the center of Figure 7). The opening 25 opens from the through hole 24 toward the front end face 35. The opening 25 can be filled with gel material. The opening 25 communicates with the through hole 24, as well as with the upper surface 31 (mounting surface 23) side and the installation surface 22 side. In this case, the through hole 24 and the opening 25 have the same width in the direction along the installation surface 22 (X direction). However, the through hole 24 and the opening 25 may have different widths in the direction along the scanning surface (X direction). The wedge body 21 has a U-shape when viewed from the mounting surface 23 side and the installation surface 22 side.

[0049] The wedge body 21 has a recess 36 on the side facing the mounting surface 22. The recess 36 can be filled with gel material. The wedge body 21 also has a plurality of legs 37 (four in this embodiment) on the outside of the recess 36 on the mounting surface 22. The plurality of legs 37 are provided at the four corners of the wedge body 21 and can contact the object to be inspected. Furthermore, the wedge body 21 has a through hole 38 that penetrates from the through hole 24 to the end face 32. The through hole 38 discharges excess sonicote (glycerin paste) or water that is filled between the gel material and the vertical probe 12.

[0050] The wedge 13 is attached to the vertical probe 12. The vertical probe 12 is cylindrical in shape and has a male threaded portion at its axial end. On the other hand, the wedge 13 has a female threaded portion on the mounting surface 23 side of the through hole 24 in the wedge body 21. The vertical probe 12 is fixed by inserting the male threaded portion of the wedge 13 into the through hole 24 of the wedge body 21 and screwing it into the female threaded portion. In this case, it is obvious that the mounting surface 23 should have the minimum necessary female threaded portion so that the male threaded portion can be screwed into the female threaded portion.

[0051] <Variation> Note that the mounting structure of the wedge 13 to the vertical probe 12 is not limited to the screw structure described above. Figure 8 is a schematic diagram showing a modified example of the wedge of the first embodiment.

[0052] The wedge 13 is attached to the vertical probe 12. The vertical probe 12 is not limited to a cylindrical shape, and the flange portion 41 is fixed to it. The flange portion 41 of the vertical probe 12 is in close contact with the mounting surface 23 of the wedge 13 so as to align with the through hole 24 of the wedge 13. The flange portion 41 of the vertical probe 12 is then fixed to the wedge 13 by multiple fixing screws 42.

[0053] <Operation of the ultrasound machine> Figure 9 is a schematic diagram illustrating the operation of the wedge in the first embodiment, and Figure 10 is a schematic diagram showing an example of inspection results using an ultrasonic inspection device.

[0054] As shown in Figure 9, the probe 11 has a wedge 13 attached to the vertical probe 12, and the through hole 24 and opening 25 of the wedge 13 are filled with gel material. The probe 11 positions the mounting surface 22 of the wedge 13 facing the inspection surface 101 of the object to be inspected 100. Then, by pressing the wedge 13 against the inspection surface 101 of the object to be inspected 100, the mounting surface 22 of the wedge 13 and the inspection surface 101 of the object to be inspected 100 come into close contact. At this time, since a liquid such as glycerin paste is filled to improve the contact between the vertical probe 12 and the gel material, the liquid is discharged from the through hole 38. In addition, the gel is indented by the volume of the liquid, but the deformation of the gel can be released through the opening 25.

[0055] The vertical probe 12 transmits ultrasonic waves from its transmitter toward the object to be inspected 100. The ultrasonic waves from the vertical probe 12 propagate directionally through the gel material of the through-hole 24 and reach the inspection surface 101 of the wedge 13. The ultrasonic waves that reach the inspection surface 101 then propagate through the inside of the object to be inspected 100, are reflected at the defective area, and then return to the receiver of the vertical probe 12.

[0056] The ultrasonic waves transmitted from the vertical probe 12 toward the object under inspection 100 propagate directionally through the gel material, refract at the boundary between the gel material and the object under inspection 100 according to Snell's law, and propagate inside the object under inspection 100. Conventional wedges do not have an open section 25, and the gel material is filled only in the through-hole 24. Therefore, while the ultrasonic waves propagate directionally through the gel material and inside the object under inspection 100, they also propagate with a certain degree of spread. As shown in Figure 6, the ultrasonic waves scatter at the triple point where the wedge (structural material), the object under inspection 100, and the gel material overlap in the direction of flaw detection, and are transmitted back into the gel material, causing noise to be generated near the inspection surface 101 of the object under inspection 100. Furthermore, the ultrasonic waves reflected from the inspection surface 101 of the object being inspected 100 enter the inner surface of the through hole 24 and, as they propagate through the wedge (structural material), split into longitudinal and transverse waves. These waves then reflect once or more inside the structural material and return to the vertical probe 12, which also generates noise.

[0057] On the other hand, in the first embodiment, the wedge 13 has gel material filled in the through hole 24 and the open portion 25. Therefore, the ultrasonic waves that propagate with a certain degree of spread are suppressed from scattering at the triple point where the structural material of the wedge 13, the object to be inspected 100, and the gel material, which are located in the direction of flaw detection, overlap, and the generation of noise near the inspection surface 101 of the object to be inspected 100 is suppressed. In addition, the reflected waves of ultrasonic waves reflected by the inspection surface 101 of the object to be inspected 100 only propagate through the open portion 25 without reaching the inner surface of the through hole 24, and the generation of noise is suppressed here as well.

[0058] As shown in Figure 10, when a wedge is used in which there is no conventional open section 25 and only the through-hole 24 is filled with gel material, noises a and b are generated as shown by the dotted lines in Figure 10. Noise a is noise generated by the scattering of ultrasonic waves at the triple point where the wedge, the object to be inspected 100, and the gel material overlap. Noise b is noise generated when ultrasonic waves reflected from the inspection surface 101 of the object to be inspected 100 propagate to the wedge.

[0059] On the other hand, when using the wedge 13 in which the through-hole 24 and open portion 25 of the first embodiment are filled with gel material, the generation of noise a and b, as shown by the dotted lines in Figure 10, is suppressed. Therefore, only the defective parts shown by the solid lines in Figure 4 can be appropriately detected. In other words, by suppressing the noise generated by the above-mentioned technical problem a, defects at shallow positions in the object to be inspected 100 can be efficiently detected. Furthermore, by suppressing the noise generated by the above-mentioned technical problem b, defects at deeper positions in the object to be inspected 100 can be efficiently detected.

[0060] The wedge 13 of the first embodiment comprises a wedge body 21, an installation surface 22, a mounting surface 23, a through hole 24, and an opening 25. The opening 25 opens from the through hole 24 to the front end face 35 in the through direction, allowing for filling with gel material. Therefore, it is possible to suppress the generation of noise due to scattering of ultrasonic waves and noise due to the incidence of reflected waves onto the wedge body 21, thereby improving the accuracy of ultrasonic inspection.

[0061] [Second Embodiment] Because the structure of the gel wedge in the second embodiment is "U-shaped," there is a risk of reduced structural strength if sufficient structural material thickness cannot be taken into consideration due to physical interference during flaw detection. In other words, when gripped by a human hand or a jig used to fix it to the end effector of a scanner / robot, the structural material may deform, and the change in the shape of the gel may affect the contact area between the vertical probe, the specimen, and the gel, which affects flaw detection sensitivity.

[0062] Therefore, reinforcing materials that are less likely to generate noise in the structural material should be provided. When adding reinforcing materials, it is best to tilt them at an angle of 10 degrees or more and place the reinforcing materials as close to the side as possible so that reflected waves from the reinforcing materials do not generate technical problem b. The reason for this is that the former makes it possible to prevent reflected waves from the reinforcing materials from directly reaching the vertical probe, and the latter is that the longitudinal wave sound velocity in gel is about 60% slower than that in resin, so by increasing the distance over which the sound propagates in the gel region, the location of the noise can be moved to outside the region where defect detection is expected.

[0063] Figure 11 is a cross-sectional view showing the wedge of the second embodiment. Note that components having the same function as those in the first embodiment described above are denoted by the same reference numerals, and detailed descriptions are omitted.

[0064] As shown in Figure 11, the wedge 13A has a connecting member 51. The wedge body 21 has a through hole 24 and an open portion 25 inside, so that when viewed from the mounting surface 23 side and the installation surface 22 side, it has a U-shape. Therefore, the wedge body 21 has a pair of arms 21a that extend from the end face 32 side to the end face 35 side. The connecting member 51 connects the pair of arms 21a inside the open portion 25. By connecting the pair of arms 21a, the connecting member 51 functions as a reinforcing member for the pair of arms 21a.

[0065] Furthermore, the connecting member 51 is positioned along an inclination direction that is tilted by a predetermined angle horizontally with respect to the direction (X direction) perpendicular to the communication direction (Y direction) that connects the through hole 24 and the opening 25. By tilting the connecting member 51 horizontally with respect to the X direction, when the reflected ultrasonic wave is incident on the connecting member 51, the propagation of the reflected wave toward the vertical probe 12 can be suppressed.

[0066] The connecting member 51 is cylindrical in shape, but may also be polygonal. There is usually one connecting member 51, but may be multiple. The connecting member 51 is placed in the open section 25, but may also be placed outside the open section 25, on the side of the installation surface 22, the mounting surface 23, the end surface 35, etc. However, it is preferable to place the connecting member 51 at a position away from the installation surface 22 and the through hole 24.

[0067] The wedge 13A of the second embodiment comprises a wedge body 21, an installation surface 22, a mounting surface 23, a through hole 24, an open portion 25, and a connecting member 51. The connecting member 51 connects a pair of arms 21a of the wedge body 21. Therefore, since the connecting member 51 functions as a reinforcing member connecting the pair of arms 21a, deformation is suppressed by reinforcing the wedge body 21, thereby improving the detection accuracy of the probe 11A.

[0068] [Third Embodiment] As described in the second embodiment, the reflected waves from the reinforcing material can be controlled by the position where the reinforcing material is applied. Therefore, instead of treating them as noise, they can be actively utilized as a means to determine whether or not the wedge is firmly pressed against the object during automated flaw detection.

[0069] This section describes the position of the reinforcing material attached to the structural material of the gel wedge when actively utilizing reflected waves from the reinforcing material. In the structure of the gel wedge of this embodiment, the main ultrasonic path is a single region of gel, excluding the area within the object being examined. For example, if the object being examined is not only a flat plate but also a pipe, and the gel wedge is in close contact with it, the ultrasonic waves incident at the incident point will be reflected at an angle equal to the angle of incidence relative to the normal at the incident point and propagate through the gel. Therefore, in the second embodiment, the reinforcing material was tilted by 10 degrees or more on the path of reflection at an equal angle. By deliberately placing the reinforcing material in a direction perpendicular to the reflected waves propagating through the gel (i.e., not tilted by 10 degrees or more), it is possible to strongly receive the reflected waves from the reinforcing material and to predict and control the position of the reflected waves from the reinforcing material. Furthermore, by considering the shape of the reinforcing material, the strength can also be controlled to some extent. In this state, if the pressure on the gel wedge is insufficient, such as when one side of the four legs of the gel wedge is lifted from the pipe, the gel will deform to some extent, causing the normal vector to change and the reflection intensity to change significantly.

[0070] Figure 12 is a cross-sectional view showing the wedge of the third embodiment. Components having the same function as those in the first embodiment described above are denoted by the same reference numerals, and detailed descriptions are omitted.

[0071] As shown in Figure 12, the wedge 13B has a reflective member 52. The wedge body 21 has a through hole 24 and an open section 25 inside, so that when viewed from the mounting surface 23 side and the installation surface 22 side, it has a U-shape. Therefore, the wedge body 21 has a pair of arms 21a that extend from the end face 32 side to the end face 35 side. The reflective member 52 connects the pair of arms 21a inside the open section 25. By connecting the pair of arms 21a, the reflective member 52 can also function as a reinforcing member for the pair of arms 21a.

[0072] Furthermore, the reflective member 52 is positioned along a direction (X direction) perpendicular to the communication direction (Y direction) that connects the through hole 24 and the opening 25. The reflective member 52 is capable of reflecting ultrasonic waves toward the through hole 24 on the mounting surface 23 side. That is, ultrasonic waves transmitted from the vertical probe 12 reach the reflective member 52 after being reflected by the object being inspected. The reflected waves that reach the reflective member 52 return to the vertical probe 12 through the through hole 24.

[0073] The reflective member 52 controls the direction of reflection of the reflected wave incident from the object being inspected. By controlling the direction of the reflected wave reflected by the reflective member 52, the reflected wave is not treated as noise, but rather used as a signal to determine whether the wedge 13B is properly pressed against the object being inspected and in close contact. The ultrasonic waves that reach the object being inspected from the vertical probe 12 are reflected at an angle equal to the angle of incidence with respect to the normal at the point of incidence and propagate inside the gel-containing area of ​​the open section 25. Therefore, the reflective member 52 is positioned along the path of reflection at an equal angle, in a direction (X direction) perpendicular to the reflected wave propagating inside the gel material. As a result, the reflective member 52 can strongly receive the reflected wave from the object being inspected, and can also appropriately predict and control the position of the reflected wave from the reflective member 52. In this case, the intensity can also be controlled to some extent by considering the shape of the reflective member 52.

[0074] The reflective member 52 is cylindrical in shape, but may also be polygonal. While there is usually only one reflective member 52, multiple reflective members may be provided.

[0075] The wedge 13B of the third embodiment comprises a wedge body 21, an installation surface 22, a mounting surface 23, a through hole 24, an opening 25, and a reflective member 52. The reflective member 52 connects a pair of arms 21a of the wedge body 21 at the opening 25. Therefore, the reflective member 52 can receive reflected waves from the object to be inspected and appropriately predict and control the position of the reflected waves to determine whether the wedge 13B is in proper contact with the object to be inspected.

[0076] [Fourth Embodiment] The probes described in the first to third embodiments may be used by an inspector to inspect an object by hand, or they may be used for automated inspection using a general scanner or robot. Furthermore, the flaw detector may consist of a single set of pulse receivers, or by increasing the number of pulse receivers, multiple piezoelectric elements may be used to transmit and receive ultrasonic waves simultaneously. The configuration described below is general and will therefore be briefly explained.

[0077] In this embodiment, the contactability of the probe using the gel wedge described in the third embodiment is determined, and flaw detection is automatically performed again. The simplest method is to input the reflected wave intensity from the reinforcing material obtained when it is in proper contact with the object to be examined, and the acceptable range of fluctuation in reflected wave intensity during scanning, and set a threshold, and monitor to ensure that the threshold is not exceeded.

[0078] Specifically, the necessary flaw detection and scanning conditions, such as ultrasonic transmission and reception conditions and scanning conditions (including data acquisition timing), are read and the process begins. During flaw detection and scanning, the signal strength from the reinforcing material is monitored among the acquired waveforms. It is determined whether the signal strength exceeds a threshold. If the threshold is exceeded, flaw detection and scanning are performed again at that location. If the threshold is not exceeded, flaw detection and scanning continue, and it is determined whether the planned scanning trajectory has been completed. If the scanning trajectory is not completed, the remaining scanning trajectory plan is executed. If the scanning trajectory is completed, the inspection is terminated.

[0079] It should be noted that the above explanation assumes that the only signal usable for determining the quality of contact is the reflected wave from the reinforcing material. However, if other signals such as material noise and other steady-state shape echoes can also be utilized, it is clear that machine learning or similar methods can be used to make a comprehensive determination in addition to the reflected wave from the reinforcing material.

[0080] Figure 13 is a simplified block diagram representing the ultrasound inspection system of the fourth embodiment, and Figure 14 is a flowchart representing the ultrasound inspection method. Components having the same functions as those in the third embodiment described above are denoted by the same reference numerals, and detailed explanations are omitted.

[0081] As shown in Figure 13, the ultrasound inspection system 60 comprises a probe 11B, a transmitting / receiving unit 61, a scanning unit 62, a control processing unit 63, an input unit 64, and a display unit 65.

[0082] The probe 11B has a wedge 13B attached to the vertical probe 12. The transmitting / receiving unit 61 has a pulse receiver 71 and a transmitting / receiving controller 72, and the pulse receiver 71 is connected to the probe 11. The scanning unit 62 has a scanner / robot 73 and a scanner / robot controller 74, and the probe 11B is attached to the scanner / robot 73.

[0083] The control processing unit 63 includes a control device 75, a waveform processing unit 76, and a storage device 77. The control processing unit 63 is connected to the transmitting / receiving unit 61 and the scanning unit 62. The storage device 77 stores ultrasonic transmission / reception conditions, ultrasonic waveforms (acquired data), ultrasonic waveform processing conditions, transducer scanning trajectory, transducer scanning conditions, transducer position, data linking information, processing result information, display conditions, etc. The waveform processing unit 76 performs waveform processing based on data acquired from the transducer 11B via the transmitting / receiving unit 61. The control device 75 performs various controls based on the processing data from the waveform processing unit 76 and the stored data from the storage device 77. The input unit 64 is, for example, a keyboard or mouse and is connected to the control processing unit 63. The display unit 65 is a display and is connected to the control processing unit 63.

[0084] Furthermore, the control processing unit 63 is a control device, and the control device is a computer, for example, a CPU (Central Processing Unit) or MPU (Micro Processing Unit), which executes various programs stored in the memory unit using the memory unit as a working area.

[0085] The ultrasonic inspection system 50 has a transducer 11B according to the third embodiment. As shown in Figures 13 and 14, in step 001, the control processing unit 63 reads the necessary flaw detection and scanning conditions, such as the ultrasonic transmission and reception conditions and scanning conditions (including data acquisition timing). The control processing unit 63 then transmits ultrasonic waves from the transducer 11B and controls the scanner and robot to start scanning. In step 002, the control processing unit 63 monitors the signal intensity of the ultrasonic waves received from the reflector 52 (see Figure 12) among the waveforms acquired by the transducer 11B. Here, the position of the reflector 52 fixed to the wedge 13B of the transducer 11B is known in advance, and the ultrasonic signal from the reflector 52 can be identified.

[0086] In step 003, the control processing unit 63 determines whether the ultrasonic signal intensity from the reflective member 52 exceeds a preset threshold, that is, whether the ultrasonic signal intensity from the reflective member 52 is within the threshold. If the control processing unit 63 determines that the ultrasonic signal intensity from the reflective member 52 exceeds the threshold (No), in step 004, it displays that the inspection result may not be appropriate and performs the flaw detection and scanning again.

[0087] On the other hand, if the control processing unit 63 determines that the ultrasonic signal intensity from the reflecting member 52 is within the threshold (Yes), it continues the flaw detection and scanning in step 005. Then, in step 006, the control processing unit 63 determines whether the planned scanning trajectory has been completed. If the control processing unit 63 determines that the planned scanning trajectory has not been completed (No), it returns to step 003. On the other hand, if the control processing unit 63 determines that the planned scanning trajectory has been completed (Yes), it terminates the process.

[0088] The ultrasonic inspection system 50 of the fourth embodiment performs ultrasonic inspection using a probe 11B having a wedge 13B provided with a reflective member 52. Therefore, by determining the signal strength of the ultrasonic waves from the reflective member 52, it is possible to determine whether or not the probe 11B is in proper contact with the object to be inspected.

[0089] [Fifth Embodiment] The fifth embodiment describes a gel wedge structure for a dual-element transducer, which is attached to a vertical dual-element transducer and divides the region where ultrasonic waves propagate to the transmitting and receiving sides. Here, we will explain the reason for using a dual-element transducer. The wedge (delay material) for the vertical transducer can be described as a special wedge in which the contact surface of the angled transducer wedge and its opposite surface are parallel. The wedge for angled flaw detection has a structure in which the mounting surface of the vertical transducer is inclined with respect to the contact surface, making it difficult for reflected waves to directly return to the vertical transducer. On the other hand, since the wedge for vertical flaw detection is a parallel flat plate, multiple reflections occur within the wedge, and strong reflected waves are generated many times, so it can be said that it is a structure that generates strong noise originating from the wedge. As a countermeasure, in addition to the piezoelectric element that emits ultrasonic waves, a piezoelectric element dedicated to receiving is provided, and by using a dual-element transducer separated by an acoustic separation plate, it is possible to suppress noise (dead zone) due to reverberation caused by the piezoelectric transducer and transducer structure, as well as noise from the surface of the object under test. Conventionally, a wedge structure for dual-element transducers, used to conform to the outer surface of a test object, is known to have a relatively thin cork sandwiched between the transmitting and receiving wedges. Changing the transmit / receive split wedge for dual-element transducers to a gel wedge presents challenges regarding cork durability, acoustic isolation, and manufacturing / field operational feasibility. Incidentally, angled dual-element transducers are sometimes used when a thin wedge portion is required, such as in inspections of confined spaces. This invention describes the structure of a transmit / receive split gel wedge for use with vertical dual-element transducers, but it is obvious that it can also be applied to angled transmit / receive split gel wedges.

[0090] Regarding durability issues, the acoustic separator plate where the vertical dual transducer and wedge come into contact does not move during scanning and is therefore not damaged because the transducer and wedge are fixed. However, the acoustic separator plate near the contact point between the gel and the specimen comes into direct contact with the specimen, and the gel is also displaced in the opposite direction to the scanning direction during scanning. It is easy to predict that repeated scanning will cause wear and damage to the cork. Not only will the intrusion of liquid coupling medium into the area where the acoustic separator plate has detached increase noise, but cork fragments and air bubbles can get caught in the contact surface between the transducer and the specimen, causing a decrease in signal. In particular, in automated ultrasonic testing, this is an issue that should be avoided because removing the probe for repair and then recalibrating the sensitivity and retesting may waste unnecessary time.

[0091] Regarding the challenges of acoustic isolation, the vertical dual transducer and the acoustic isolation plate portion of the transmit / receive split wedge must be in close contact to prevent noise from being transmitted from the transmitting element to the receiving element via the adhesive surface. Similarly, the gel on the surface of the subject must also be in close contact with the acoustic isolation plate to suppress ultrasonic waves transmitted from the transmitting gel to the subject surface and from the subject surface to the transmitting gel.

[0092] In terms of manufacturability and on-site operational feasibility, injecting and molding the gel material while an acoustic separator is present increases the risk of air bubbles being incorporated into the gel due to irregularities on the cork surface. Furthermore, the cork cannot be replaced when it wears out or becomes damaged.

[0093] The fifth embodiment solves the above-mentioned problems. Specifically, the acoustic separator plate inside the vertical dual transducer and the acoustic separator plate of the gel wedge need to be in relatively tight contact to minimize gaps when fixing the vertical dual transducer, so cork is preferable, and for the acoustic separator plate used on the subject side, a flexible film that can withstand the deformation of the gel is preferable. In other words, it is preferable to have a two-layer structure for the acoustic separator plate. Furthermore, it is preferable to have grooves processed for the cork so that it does not move when pressed.

[0094] The film to be used must be flexible and soft, and also softer than the material being scanned to prevent scratching the surface of the sample. By using a flexible film, the film can follow the deformation of the gel when the probe is pressed against the sample and scanned, thus preventing damage to the film. As a flexible and sound-impermeable material, multilayer films or closed-cell films are suitable.

[0095] A multilayer film consists of two or more layers, and can be made by providing at least one layer containing a large amount of air, such as a non-bonding layer (an extremely thin air layer) or a mesh, or by providing one or more layers of metal foil with a significantly different acoustic impedance from the resin film. If possible, the edges of the multilayer film should be sealed. This is to prevent liquids such as glycerin paste applied when in contact with the object from penetrating the film and reducing its acoustic isolation properties. As for closed-cell films, if the cells are closed, they do not absorb water, and depending on the proportion of cells, they block sound and also have excellent flexibility and abrasion resistance.

[0096] In terms of practicality in the field, if the film shifts position or becomes damaged, the structure should be such that the gel-filled wedge is manufactured in sections, allowing the damaged or shifted cork film to be replaced with a healthy one, or returned to its designated position and secured with screws or similar fasteners.

[0097] By adopting a transmit / receive split gel wedge structure that possesses the above features, a gel wedge suitable for automated ultrasonic testing can be manufactured. Furthermore, this structure can also be applied to a transmit / receive split gel wedge for an angled probe used to avoid noise from multiple echoes within the wedge when it is necessary to reduce the height of the angled probe wedge in situations where the probe is inserted into a narrow space to perform angled flaw detection on a thick plate.

[0098] Figure 15 is a cross-sectional view showing the wedge of the fifth embodiment. Note that components having the same function as those in the first embodiment described above are denoted by the same reference numerals, and detailed descriptions are omitted.

[0099] As shown in Figure 15, the probe 11C comprises a vertical dual transducer probe 12C and a wedge 13C.

[0100] The vertical dual transducer 12C is a dual-transducer ultrasonic transducer in which a transmitting unit 12a equipped with a piezoelectric element for transmitting and a receiving unit 12b equipped with a piezoelectric element for receiving are separated and independent on the O2 line by an acoustic separator plate.

[0101] The wedge 13C is attached to the vertical dual transducer 12C. The flange portion 41 of the vertical dual transducer 12C is fixed. The vertical dual transducer 12C is positioned so that the flange portion 41 is in close contact with the wedge 13C and is fixed to the wedge 13C by multiple fixing screws 42.

[0102] <Wedge> Figure 16 is a front view representing the wedge of the fifth embodiment, and Figure 17 is a top view representing the wedge.

[0103] As shown in Figure 15, the wedge 13C comprises a wedge body 81, an installation surface 82, a mounting surface 83, a through hole 84, and a separation plate 85.

[0104] The wedge body 81 is made of, for example, a resin material, but is not limited to a resin material. The mounting surface 82 is provided on the lower surface of the wedge body 81. The mounting surface 82 is preferably flat, but may be shaped to match the inspection surface of the object to be inspected. The mounting surface 83 is provided on the upper surface of the wedge body 81. The mounting surface 83 is the surface for mounting the vertical dual transducer 12C. The mounting surface 83 is provided on the opposite side of the wedge body 81 from the mounting surface 82. When a vertical dual transducer with a gel wedge is used, the mounting surface 83 of the gel wedge is parallel to the mounting surface 82. When an oblique-angled dual transducer with a gel wedge is used, the mounting surface 83 of the gel wedge is only inclined with respect to the mounting surface 82.

[0105] The through-hole 84 penetrates from the mounting surface 83 to the installation surface 82. The through-hole 84 is often shaped to match the piezoelectric element of a vertical dual transducer. For example, if two semicircular piezoelectric elements are used as the transmitting and receiving elements, the through-hole 84 is circular and has a center concentric with the axis O2 of the wedge body 81. If it is rectangular, it may be rectangular, and the through-hole should be larger than the size of the piezoelectric element. For simplicity in illustration, this description assumes the use of a vertical transducer in which two semicircular piezoelectric elements are separated by an acoustic isolation plate and arranged to form a circle. The through-hole 84 can be filled with gel material.

[0106] The separation plate 85 is plate-shaped and arranged along the radial and axial directions of the through hole 84. The separation plate 85 separates the inside of the through hole 84 into the transmitting unit 11a side and the receiving unit 11b side. Preferably, the separation plate 85 is made of a porous material with higher sound absorption than the wedge body 81. The separation plate 85 has a first separation plate 85A and a second separation plate 85B. The first separation plate 85A is arranged inside the through hole 84 on the mounting surface 83 side of the wedge body 81. The second separation plate 85B is arranged inside the through hole 84 on the installation surface 82 side of the wedge body 81.

[0107] In this case, the first separator plate 85A and the second separator plate 85B are in close contact at one end along the axis O2. The other end of the first separator plate 85A along the axis O2 can be in close contact with the vertical dual transducer probe 12C which is attached to the mounting surface 83. Furthermore, the other end of the second separator plate 85B along the axis O2 can be in close contact with the object to be inspected. Even if the second separator plate 85B shifts from its close contact state, creating a small gap between the first separator plate 85A and the second separator plate 85B, as long as there is an air layer without the gels being in close contact, it will function as a third separator plate, and ultrasonic waves will not propagate from the transmitting gel to the receiving gel.

[0108] The second separating plate 85B is formed from a material that is softer than the first separating plate 85A. For example, it is preferable that the first separating plate 85A is made of cork and the second separating plate 85B is made of film.

[0109] By the way, since the wedge 13C requires the placement of a separation plate 85 in the through hole 84, the wedge body 81 is divided into multiple parts (two in this embodiment). That is, the wedge body 81 is composed of two divided parts 91 and 92 that are divided radially.

[0110] As shown in Figures 16 and 17, the divided bodies 91 and 92 have a first curved surface 93 formed on the upper part, which is one side of the axis O2. The first curved surface 93 is for the insertion or mounting of the tip of the vertical dual transducer probe 12C. The divided bodies 91 and 92 have a second curved surface 94 formed on the lower part, which is the other side of the axis O2. The second curved surface 94 forms a through hole 84 (see Figure 9). The outer diameter of the first curved surface 93 is larger than the outer diameter of the second curved surface 94, thereby forming a stepped portion 95. In addition, the divided bodies 91 and 92 have recesses 96 at each circumferential end of the second curved surface 94, aligned with the axis O2.

[0111] Furthermore, the divided sections 91 and 92 are provided with mounting holes 97 for connecting the divided sections 91 and 92 to each other, as well as mounting holes 98 for attaching the vertical dual transducer probe 12C.

[0112] As shown in Figure 15, the wedge 13C is constructed by combining divided bodies 91 and 92 in a cylindrical shape. The divided bodies 91 and 92 are connected by fixing screws (not shown) inserted into mounting holes 97. At this time, the first separation plate 85A and the second separation plate 85B are fitted into and clamped in the recesses 96 of the divided bodies 91 and 92. Furthermore, when the vertical dual transducer probe 12C is mounted on the wedge 13C, it is positioned by the stepped portion 95.

[0113] One challenge in on-site operation is that the separation plate 85 may shift position or become damaged. However, since the wedge body 81 is composed of divided parts 91 and 92, separating the divided parts 91 and 92 makes it easy to adjust the position and replace the first separation plate 85A and the second separation plate 85B that make up the separation plate 85.

[0114] As shown in Figure 15, the wedge 13C may have an opening 89 that opens from the through hole 84 toward the side, as in the first embodiment. The opening 89 is linear in shape, but may also have a shape that widens toward the through hole 84, as shown by the dashed line. By providing the opening 89, when the gel filled in the through hole 84 deforms, the deformation of the gel is allowed to escape, stabilizing the contact and making it easier to maintain a constant sensitivity. In addition, the wedge 13C may have a recess on the mounting surface 82, as in the first embodiment. By providing a recess, as shown in Figure 8, a leg portion 37 is provided, and the leg portion 37 similarly stabilizes the contact when pressed, making it easier to maintain a constant sensitivity.

[0115] <Variation> Figure 18 is a front view showing a first modified example of the wedge according to the fifth embodiment, and Figure 19 is a plan view showing a first modified example of the wedge according to the fifth embodiment.

[0116] The separation plate 85 comprises a first separation plate 85A and a second separation plate 85B. The first separation plate 85A is made of cork, and the second separation plate 85B is made of film, which is a softer material than the first separation plate 85A. Since the first separation plate 85A and the second separation plate 85B differ in thickness and hardness, a structure that suppresses displacement or increases friction to make movement difficult is effective in order to firmly sandwich the first separation plate 85A and the second separation plate 85B with the divided parts 91 and 92 to maintain acoustic separation.

[0117] As shown in Figures 18 and 19, the divided bodies 91 and 92 have a first curved surface 93 to which the tip of the vertical dual transducer probe 12C is attached or inserted, and a second curved surface 94 that forms a through hole 84 (see Figure 15). The divided bodies 91 and 92 are provided with recesses 96 at each circumferential end of the second curved surface 94. When the divided bodies 91 and 92 are connected by fixing screws (not shown), the first separation plate 85A and the second separation plate 85B are fitted into the recesses 96 of the divided bodies 91 and 92 and held in place.

[0118] In the first modified example, the recess 96 has a first recess 96a and a second recess 96b. The first recess 96a supports the first separation plate 85A, and the second recess 96b supports the second separation plate 85B. A step is provided between the first recess 96a and the second recess 96b. That is, the depth of the second recess 96b (thickness of the second separation plate 85B) is smaller than the depth of the first recess 96a (thickness of the first separation plate 85A). Therefore, when the hardness of the first separation plate 85A and the second separation plate 85B differs, the first recess 96a and the second recess 96b can firmly support the first separation plate 85A and the second separation plate 85B by matching the respective depths of the first recess 96a and the second recess 96b to the thicknesses of the first and second separation plates 85A and 85B, respectively.

[0119] Figure 20 is a front view showing a second modified example of the wedge according to the fifth embodiment, and Figure 21 is a plan view showing a second modified example of the wedge according to the fifth embodiment.

[0120] As shown in Figures 20 and 21, in the second modified example, the recess 96 has a first recess 96c and a second recess 96d. The first recess 96c supports the first separation plate 85A, and the second recess 96d supports the second separation plate 85B. A step is provided between the first recess 96c and the second recess 96d. That is, the width of the second recess 96b (width of the second separation plate 85B) is smaller than the width of the first recess 96c (width of the first separation plate 85A). As a result, the first recess 96c is wider than the second recess 96d, which makes it possible to firmly contact the first separation plate 85A supported by the first recess 96c with the vertical dual transducer probe 12C. In addition, it is possible to prevent the first separation plate 85A from shifting toward the second separation plate 85B and to mount the separation plate 85 in a more accurate position.

[0121] Figure 22 is a front view showing a third modified example of the wedge according to the fifth embodiment.

[0122] The third modified form has the configuration of both the first and second modified forms. As shown in Figure 22, in the third modified form, the recess 96 has a first recess 96e and a second recess 96f. The first recess 96e supports the first separation plate 85A, and the second recess 96f supports the second separation plate 85B. A step is provided between the first recess 96e and the second recess 96f. That is, the depth and width of the second recess 96b are smaller than the depth and width of the first recess 96e. Therefore, the third modified form can achieve the effects of both the first and second modified forms.

[0123] In addition to the above-described configuration, the surface roughness of the recess 96 may be made rougher. In this case, the frictional resistance between the divided bodies 91 and 92 and the first separating plate 85A and the second separating plate 85B can be increased, thereby suppressing the displacement of the first separating plate 85A and the second separating plate 85B.

[0124] The wedge 13C of the fifth embodiment comprises a wedge body 81, an installation surface 82, a mounting surface 83, a through hole 84, and a separation plate 85. The separation plate 85 has a first separation plate 85A positioned on the mounting surface 83 side and a second separation plate 85B positioned on the installation surface 82 side and formed of a softer material than the first separation plate 85A. Therefore, the durability of the separation plate 85 can be improved while ensuring acoustic separation performance, thereby improving the accuracy of ultrasonic inspection.

[0125] [Effects of this embodiment] The probe wedge according to the first embodiment is a wedge 13, 13A, 13B, 13C that is attached to the vertical probe 12 and vertical dual transducer probe 12C of the probes 11, 11A, 11B, 11C, and comprises a block-shaped wedge body 21, an installation surface 22 provided on the wedge body 21, an installation surface 23 provided on the opposite side of the installation surface 22 on the wedge body 21 and inclined with respect to the installation surface 22, to which the vertical probe 12 and vertical dual transducer probe 12C can be attached, a through hole 24 provided along the through-direction penetrating from the installation surface 23 to the installation surface 22 and into which gel material can be filled, and an opening 25 that opens from the through hole 24 to the front end face 35 in the through-direction and into which gel material can be filled.

[0126] According to the first embodiment of the probe wedge, the accuracy of ultrasonic inspection can be improved by suppressing the generation of noise due to scattering of ultrasonic waves and noise due to the incidence of reflected waves onto the wedge body 21. In addition, when the wedges 13, 13A, and 13B of the probe 11 are pressed against the inspection surface 101 of the object to be inspected 100, the deformation of the gel material can be released through the opening 25.

[0127] The probe wedge according to the second embodiment is the probe wedge according to the first embodiment, further having a U-shape when viewed from the mounting surface 22 side. This allows for an appropriate area to be secured in the wedge body 21 where ultrasonic waves interfere. In addition, the U-shape results in a smooth shape, allowing the gel material to deform smoothly. Furthermore, the U-shape is robust because there are no stress concentration points. Moreover, since the piezoelectric element inside a vertical probe is often disc-shaped, and the outer shape of the probe is often cylindrical, the wedge only needs to be hollowed out once to form a cylindrical shape, resulting in a rational shape for wedge manufacturing.

[0128] The probe wedge according to the third embodiment is a probe wedge according to the first or second embodiment, further comprising legs 37 at the corners of the mounting surface 22 that can contact the object to be inspected 100. This allows the probe wedges 13, 13A, 13B, and 13C to be placed on the object to be inspected 100 via the legs 37, thereby improving the positioning accuracy of the probe wedges 13, 13A, 13B, and 13C.

[0129] The probe wedge according to the fourth embodiment is a probe wedge according to any one of the first to third embodiments, further having a pair of arms 21a formed by a through hole 24 and an open portion 25, and a connecting member 51 is provided to connect the pair of arms 21a. As a result, the posture is stabilized by pressing the solid legs 21a, rather than the gel material portion, against the object to be inspected 100, thereby improving positioning accuracy, and the durability of the gel material can be improved by suppressing strong force being applied directly to the gel material.

[0130] The probe wedge according to the fifth embodiment is the probe wedge according to the fourth embodiment, further wherein the connecting member 51 is arranged along an inclined direction that is inclined by a predetermined angle with respect to a direction perpendicular to the communication direction that connects the through hole 24 and the open portion 25. This makes it possible to suppress ultrasonic waves reflected by the connecting member 51 from reaching the vertical probe 12 and the vertical dual transducer probe 12C.

[0131] The probe wedge according to the sixth embodiment is a probe wedge according to any one of the first to third embodiments, further having a pair of arms 21a formed by a through hole 24 and an open portion 25, and is provided with a reflecting member 52 connecting the pair of arms 21a, the reflecting member 52 is arranged along a communication direction that connects the through hole 24 and the open portion 25, and is capable of reflecting ultrasonic waves toward the through hole 24 on the mounting surface 23 side. By guiding the ultrasonic waves reflected by the reflecting member 52 to the vertical probe 12 and the vertical dual transducer probe 12C, it is possible to determine whether the wedges 13, 13A, 13B, and 13C are in proper contact with the object to be inspected.

[0132] The seventh embodiment of the probe wedge is a probe wedge 13C that is attached to the vertical dual transducer probe 12C of the probe 11C, wherein the vertical dual transducer probe 12C has a transmitting unit 13a and a receiving unit 13b that are provided independently and do not include wedges 13, 13A, 13B, and 13C, and has a block-shaped wedge body 81, an installation surface 82 provided on the wedge body 81, and a vertical dual transducer probe 12C provided on the opposite side of the wedge body 81 from the installation surface 82 The device comprises a mounting surface 83 to which the device can be attached, a through hole 84 provided along a through-direction penetrating from the mounting surface 83 toward the installation surface 82 and into which a gel material can be filled, and a separation plate 85 arranged along the radial and axial directions of the through hole 84 to separate the through hole 84 between the transmitting unit 11a side and the receiving unit 11b side. The separation plate 85 has a first separation plate 85A positioned on the mounting surface 83 side and a second separation plate 85B positioned on the installation surface 82 side and made of a softer material than the first separation plate 85A.

[0133] According to the seventh embodiment of the probe wedge, by ensuring acoustic separation performance with the separation plate 85 and improving the durability of the separation plate 85, the accuracy of ultrasonic inspection can be improved.

[0134] The probe wedge according to the eighth embodiment is a probe wedge according to the seventh embodiment, further comprising: the first separator plate 85A and the second separator plate 85B having one end in close contact with each other; the other end of the first separator plate 85A being able to come into close contact with the vertical dual transducer probe 12C attached to the mounting surface 83; and the other end of the second separator plate 85B being able to come into close contact with the object to be inspected 100. As a result, when the area of ​​the through hole 84 of the wedge body 81 is divided into a transmitting area and a receiving area by the separator plate 85, leakage of ultrasonic waves between the transmitting area and the receiving area can be suppressed.

[0135] The probe wedge according to the ninth embodiment is a probe wedge according to the seventh or eighth embodiment, wherein the wedge body 81 is composed of a plurality of radially divided segments 91, 92, and the separation plate 85 is sandwiched by the plurality of segments 91, 92. This makes it easy to adjust the position or replace the separation plate 85 by separating the segments 91, 92.

[0136] The probe wedge according to the tenth embodiment is a probe wedge according to the ninth embodiment, further comprising a plurality of segmented bodies 91, 92 each provided with recesses 96 on their inner circumference for positioning the separation plate 85. This allows the separation plate 85 to be positioned with high precision.

[0137] The ultrasonic inspection apparatus according to the 11th embodiment comprises a vertical probe 12 and a vertical dual transducer probe 12C, which are provided with a transmitting unit and a receiving unit, and one of the probe wedges 13, 13A, 13B, 13C of the first to tenth embodiments, which are attached to the vertical probe 12 and the vertical dual transducer probe 12C. This makes it possible to improve the accuracy of ultrasonic inspection.

[0138] The ultrasonic inspection method according to the twelfth embodiment is an ultrasonic inspection apparatus 10 comprising a vertical probe 12 and a vertical dual transducer probe 12C, which are provided with a transmitting unit and a receiving unit, and a probe wedge 13B according to the sixth embodiment that is attached to the vertical probe 12 and the vertical dual transducer probe 12C, and comprises the steps of transmitting ultrasonic waves from the vertical probe 12 and the vertical dual transducer probe 12C, receiving reflected waves reflected by the reflecting member 52 from the vertical probe 12 and the vertical dual transducer probe 12C, and determining whether the reflected waves are abnormal signals. By determining the signal strength of the ultrasonic waves from the reflecting member 52, it is possible to determine whether the vertical probe 12 and the vertical dual transducer probe 12C are in proper contact with the object to be inspected. [Explanation of Symbols]

[0139] 10. Ultrasound examination equipment 11,11A,11B,11C probe 12 Vertical transducer 12C vertical dual element transducer 13, 13A, 13B, 13C Wedges 21.81 Wedge body 22,82 Installation surface 23,83 Mounting surface 24,84 through holes 25 Open area 31 Top side 32,35 End face 33,34 Side view 36 recesses 37 Legs 38 Through holes 41 Flange section 42 Fixing screws 51 Connecting member 52 Reflective material 60 Ultrasound Examination Systems 61 Transmitter / Receiver 62 Scanning Unit 63 Control Processing Unit 64 Input section 65 Display section 71 Pulse Receiver 72 Transceiver Controller 73 Scanners / Robots 74 Scanner / Robot Controller 75 Control device 76 Waveform Processing Unit 77 Storage device 85 Separation plate 85A 1st separation plate 85B 2nd separation plate 91,92 split field 93 First curved surface 94 Second curved surface 95 Stepped section 96 recess 100 items to be inspected 101 Inspection surface

Claims

1. In a probe wedge attached to the probe of a probe, The aforementioned probe has a transmitting unit and a receiving unit provided independently. The wedge body has a block shape, The wedge body has an installation surface, A mounting surface is provided on the wedge body opposite to the mounting surface, and to which the probe can be attached, A through-hole is provided along a through-direction that penetrates from the mounting surface toward the installation surface and into which a gel material can be filled, A separation plate is arranged along the radial and axial directions of the through hole to separate the through hole from the transmitting unit side and the receiving unit side. Equipped with, The separation plate comprises a first separation plate positioned on the mounting surface side and a second separation plate positioned on the installation surface side and formed of a material softer than the first separation plate. Wedge for probes.

2. The first and second separating plates are in close contact at one end, the other end of the first separating plate is capable of being in close contact with the probe attached to the mounting surface, and the other end of the second separating plate is capable of being in close contact with the object to be inspected. The probe wedge according to claim 1.

3. The wedge body is composed of a plurality of segments divided in the radial direction, and the separating plate is sandwiched between the plurality of segments. The probe wedge according to claim 1.

4. Each of the divided bodies is provided with a recess on its inner circumference for positioning the separation plate. The probe wedge according to claim 3.

5. A probe having a transmitting unit and a receiving unit, A probe wedge according to claim 1, which is attached to the probe, A flaw detector connected to the aforementioned probe, An ultrasound examination device equipped with the following features.

Images