RU2732102C2 - Ultrasonic probe and ultrasonic test system - Google Patents

Abstract

FIELD: monitoring and measuring equipment.

SUBSTANCE: probe (100) for ultrasonic system for nondestructive testing of material in process of relative movement of tested object and probe in testing direction comprises housing (110), which sets the longitudinal direction (L), which coincides with the testing direction, and the transverse direction (Q), perpendicular to the testing direction. Probe also includes a group of transceiving units (150-1, 150-2, 150-3). Each transceiving unit comprises transmitting component (T1, T2, T3) and corresponding receiving component (R1, R2, R3) and sets effective width (PB1, PB2, PB3) of testing in transverse direction (Q) with provision, in process of relative movement of tested object and probe in testing direction, possibility of testing track with width, equal to effective width of testing. Transceiving units form at least two rows (155-1, 155-2) located in longitudinal direction (L) one after another and having length in transverse direction (Q). Transceiving units from different rows are mutually shifted in transverse direction (Q) so that receiving components (R1, R2, R3) of mutually shifted transceiving units are located with mutual overlap in coverage area (U1-2, U2-3), so that the set of transceiving units provides a common effective scanning width (RRB) by means of a probe having no gaps. All transceiving units are located in probe housing (110). All transmitting components (T1, T2, T3) are electrically connected to common terminal transmitting component (AT) of the probe.

EFFECT: proposed are ultrasonic probe and ultrasonic test system.

12 cl, 5 dwg

Description

Technology area

[0001] The invention relates to a probe for an ultrasonic system for non-destructive testing (testing) of a material in the process of relative movement of the test object and the probe in the direction of testing.

State of the art

[0002] Ultrasonic testing is an acoustic process performed to detect, by means of ultrasound, structural defects in a material (called discontinuities) and to determine their dimensions. Such testing is referred to as non-destructive testing methods. In the process of non-destructive testing of a material using ultrasound (US), a sound wave travels from the probe to the test object through a bonding medium, such as a liquid film. The transmission of ultrasonic waves carrying information about the state of the material under test from the test object to the receiving probe usually occurs through the same binding medium. Separate transmitting and receiving probes can be used to emit and receive ultrasonic waves or ultrasonic pulses. In the context of the invention, a probe is understood to mean a portable device using one or more ultrasonic transducers. An ultrasonic transducer is a component that converts an electrical signal into an audio (acoustic) signal or an audio signal into an electrical signal. Typically, emitting and receiving ultrasonic transducers are combined into one probe. Where separate transmitters and receivers are used, they are also considered transceiver probes (transceiver probes). Such probes are preferred, for example, when high resolution in the near field is required. When the same ultrasonic transducers are used for both transmitting and receiving, they are referred to as pulse echo probes.

" [Опыт работы с ультразвуковой системой тестирования, имеющей цельное основание], DGZfP Annual Conference 2013 - DL2.B.2, Seiten 1-8, описана ультразвуковая система тестирования, установленная на прокатном стане непосредственно за холодильником, на входе в секцию резки. В данной ультразвуковой системе тестирования имеются 76 держателей зонда с индивидуальными пневмоприводами. При этом используются зонды-трансиверы с номинальной частотой 5 МГц. Использованные осцилляторы шириной 50 мм разделены по 4 каналам, т.е. всего имеется 304 тест-канала, требующие индивидуальной обработки результатов. Держатели зондов размещены на двух каретках для тестирования поверхности, установленных одна за другой в направлении тестирования, и взаимно смещены в поперечном направлении на ширину зонда. В результате, как отмечено в работе, обеспечивается тестирование всей поверхности (стопроцентное тестирование).[0003] Transceiver probes (transceiver probes) are used, for example, in ultrasonic testing (testing) of metal plates. Typically these slabs are 1-5 m wide, 3-30 m long, and 5-150 mm thick. A. Weber et al. "Betriebliche Erfahrungen mit einer neuen

"[Experience with a Solid Base Ultrasonic Testing System], DGZfP Annual Conference 2013 - DL2.B.2, Seiten 1-8, describes an ultrasonic testing system installed on a rolling mill directly behind a cooler at the entrance to the cutting section. This ultrasonic testing system has 76 individual pneumatic probe holders using transceiver probes with a nominal frequency of 5 MHz.The used oscillators with a width of 50 mm are divided into 4 channels, that is, there are 304 test channels in total, requiring individual processing of results. The probe holders are placed on two surface test carriages, one after the other in the test direction, and are mutually offset in the transverse direction by the width of the probe. As noted in the work, testing of the entire surface is ensured (100% testing).

[0004] The known transceiver probe, divided into four parts (four channels), contains four receiving components arranged in a row inside a rectangular (in cross-section) housing, following immediately one after the other, and a single transmitting component having a length over the entire width of the zone covered by receiving components. This design makes it possible, for example, to detect, with a high degree of reliability, standard reference defects such as flat bottom holes (Flat Bottom Hole, FBH) of the FBH-3 class (FBH with a diameter of 3 mm). However, in the case of testing, for example, metal plates, there is a growing need to detect, with a high degree of reliability, also smaller defects, for example the equivalent FBH-2 or FBH-1,2.

[0005] Patent Application Laid-open DE 19533466 A1 discloses an ultrasonic probe for non-destructive testing of material comprising a group of pulse-echo ultrasonic transducers, the transmitting / receiving surfaces of which are arranged in a first plane by at least two parallel rows and are separated from one another by gaps thus that each gap between ultrasonic transducers located in one row is covered by an ultrasonic transducer from another row. This allows a probe with a large test width to be obtained that has a substantially constant sensitivity over the entire test width.

[0006] DE 3442751 A1 discloses a metal sheet testing system using ultrasound and comprising a group of probes that can be mounted on a sheet and which are arranged in successive rows oriented transversely to the sheet feeding direction with overlapping rows in the feeding direction. Each probe contains a transmitter and a receiver.

[0007] In the laid-open patent application DE 19642072A1 described combined probing devices, which contain a plurality of receiving oscillators staggered on either side of a common transmitting oscillator. The transmitting and receiving oscillators use a common piezoelectric plate, one of their electrodes being separated. Receiving oscillators from different rows are located with partial overlap in the lateral direction, so that testing without any breaks is possible along the entire length that is covered by the transmitting oscillator.

[0008] In the laid-open patent application DE 102008002859 A1 presents a device for non-destructive testing of sheet products by means of ultrasound, using an array phased array of probes.

Disclosure of invention

[0009] The invention solves the problem of creating a probe that is suitable, for example, for use in an ultrasonic inspection system (testing) of metal plates and which, being easy to use and easily mounted in the testing system, provides a large testing width without any gaps and with high reliability even for small defects in the tested object.

[0010] To solve this problem, the invention provides a probe having the features included in claim 1 of the appended claims. Useful improvements are disclosed in the dependent clauses. The content of all claims is explained in this description.

[0011] The probe includes a housing that defines a longitudinal direction and a lateral direction orthogonal thereto. The longitudinal direction is parallel, as far as possible, with the test direction during the operation of the probe. Accordingly, the transverse direction perpendicular to the longitudinal direction is oriented perpendicular as far as possible to the indicated test direction. The probe contains a group of transceiver units, so that it is an ultrasonic multi-probe. Each of the transceiver units contains a transmitting component and a corresponding receiving component. In this case, the effective test width in the transverse direction is set in such a way that in the process of relative movement of the test object and the probe in the test direction, the transceiver unit is able to test the track with the effective test width. The size of the effective test width is somewhat smaller than the physical extent of the transceiver unit in the transverse direction, since the sensitivity of such a unit usually drops sharply near its transverse edges, so that effective testing can only be carried out within a slightly smaller width. The transceiver units form at least two rows located one after the other in the longitudinal direction and having an extension in the lateral direction. The transceiver units from different rows are mutually offset in the lateral direction so that the receiving components of the mutually offset transceiver units are located with mutual overlap in the overlapping area. As a result, the plurality of transceiver units provides an overall effective probe test width without gaps. All transceiver units are located in the probe body.

[0012] All transmitting components are electrically connected to a common terminal transmitting component of the probe. The transmitting components are electrically connected in series and can be easily synchronously activated by means of a common signal. Thus, the signal synchronization is ensured by the probe design and does not require the use of complex electronics.

[0013] Although more than two rows can be used with one or more transceiver units in each row, the transceiver units are preferably arranged in two rows longitudinally one behind the other.

[0014] Since all the transceiver units must be located in the same region of the probe body, it is possible to place these blocks in the process of manufacturing the probe inside the probe body exactly in their intended positions and, accordingly, to accurately ensure the mutual positioning of the transceiver units. The predetermined geometric configuration of the plurality of transceiver units in the probe body is usually provided by means of supporting elements, and it is permanently fixed and protected from penetration of a bonding medium by means of a suitable potting compound such as, for example, epoxy resin.

[0015] Overlapping effective test widths of the individual transceiver units could in fact also be achieved by placing the transceiver units individually in the probe body, placing the individual probes thus formed in the probe holder in two or more mutually offset rows. However, relevant tests have shown that with such a combination of individual probes it can be difficult to provide, with the required accuracy, the desired bonding gap separately for each probe in the holder. If all the sender / receiver units are located in the same probe body, the relative position of the sender / receiver units can be precisely fixed during the manufacture of the probe, so that the setting of the bonding gap can be carried out quickly and precisely simultaneously for all sender / receiver units when the probe is installed in the holder. ... As a result, it is possible to directly compare the amplitudes of signals from reference defects for all transceiver units of the probe.

[0016] By overlapping transceiver units that are laterally offset from each other in overlapping areas, it is possible to achieve that each transceiver unit uses only that region of the theoretically available test width in which a sufficiently high sensitivity is provided. In this case, the width of the overlapping zone is preferably chosen in such a way that the zones of sensitivity drop in the immediate vicinity of the transverse edges of the transceiver units overlap one another so that a noticeable drop in sensitivity between transceiver units adjacent in the transverse direction is excluded or significantly reduced compared to a well-known group of oscillators located only in one row. In some embodiments, the overlap zones have a width that is at least 10% of the effective test width for individual transceiver units, and preferably ranges from 20% to 30% of the effective test width. The fulfillment of these conditions, on the one hand, ensures that the overlap is sufficient to prevent significant drops in sensitivity in the overlapping areas. On the other hand, without making the overlap areas too wide, the effect of providing the required effective test width with the probe using a relatively small number of individual transceiver units can be achieved.

[0017] In some embodiments, the configuration is chosen such that the distance between adjacent transceiver units in the same row exceeds 30% or 50% of the effective test width of the transceiver unit. This ensures that there is no "loss" of the possible, in principle, test width or this "loss" is small.

[0018] Each of the transmitting and receiving components is preferably provided with a plate (eg, rectangular) of piezoelectric material, which in the case of the transmitting component acts as an emitting ultrasonic transducer and in the case of a receiving component as an ultrasonic receiving transducer. These plates are made separately from one another and provided with electrical contacts. In preferred embodiments, these plates are disposed obliquely with respect to one another, so that a gable configuration ("roof") is formed that is mirror-symmetrical about the plane dividing the plates. The dividing plane has a lateral extension. The "roof" angle can be 6 °, for example, although higher or lower values are also possible.

[0019] Between the ultrasonic transducers, in the plane separating them (the plane of symmetry of the roof-shaped configuration), a partition made of ultrasound-absorbing material is preferably installed. One of the purposes of the baffle is to acoustically decouple the transmitting and receiving components of the transmitting / receiving unit, so that sound transmission can only take place indirectly, through the material of the tested object, which is connected with these components during testing. The baffle can also serve to electrically decouple the ultrasonic transducers on the transmitting side and on the receiving side.

[0020] The advantages of the new concept can be realized even if only two transceiver units are used in the same row with mutual offset in the transverse direction, and only two rows of such units are installed in the probe body, mutually offset in the longitudinal direction. However, it is possible to use significantly larger numbers of transceiver units, for example from five to ten. However, in preferred embodiments, there are specifically three, four or five transceiver units in the probe housing. In this case, the first and third transceiver units are located adjacent in the first row, and the second transceiver unit is located in the second row with an offset along the row, symmetric relative to the first and third transceiver units. In the case of using four transceiver units, the fourth transceiver unit is preferably installed in the second row at a distance in the lateral direction from the second transceiver unit. If there is a fifth transceiver unit, it can be placed in the first row.

[0021] When optimizing the number, size and distribution of transceiver units, one should take into account, on the one hand, that the individual receiver signal amplitude in case of a defect of a certain size will be the higher, the smaller the effective test width or the greater the ratio of the defect size to the effective test width. Accordingly, in order to obtain a large signal amplitude, it is desirable to increase the number of transceiver units, for example, to 6-10 or more. On the other hand, with an increase in the number of transceiver units, the technological difficulties that must be overcome in order to correctly position them, as well as to conduct appropriate testing and evaluation of the electronics, also increase. If, by contrast, there are only two transceiver units located in two mutually offset rows, the required individual effective test width may be relatively large, so that the signal amplitude may not be high enough, especially in the case of small defects. Therefore, the number of transceiver units in the probe, exactly three, four or five, seems to be currently preferred.

[0022] All transceiver units located in different rows may have the same orientation of their transmitting and receiving components with respect to the longitudinal direction (test direction). Thus, all transmitting components can radiate in the same direction, for example obliquely forward or obliquely backward (along the test direction). In contrast, in some embodiments, it is envisaged that the transmitter / receiver units of the probe are distributed between the first row and the second row, with the transmitting components of the transceiver units located in different rows facing each other and located in the median (relative to the longitudinal direction) region of the probe. Due to the use of a gable configuration, the plates of the transmitting components are inclined with respect to one another so that the transmitting components radiate from the inside out in directions that diverge, due to the presence of the roof angle, at an angle to one another. As a result, better acoustic decoupling of transceiver units located in different rows can be achieved simply by the fact that the main directions of radiation are diverging. In principle, it is possible to design the probe body in such a way that for mutually offset transceiver units, the probe body has correspondingly adapted sections into which they can be inserted. As a result, a complexly contoured probe body with outer and inner corners might be required. However, the probe body preferably has a rectangular cross section. In particular, the dimensions and design of the probe body can be selected to match the cross-section and dimensions of the probe bodies using a plurality of separated oscillators, so that the probes of the invention can easily replace known multi-oscillator probes during retrofitting.

[0023] It is also possible to electrically connect some or all of the receiving components and connect them to a common terminal receiving component. However, it is desirable to electrically connect each of the receiver components to a separate terminal receiver component of the probe. As a result, it becomes possible to accurately link individual signals about defects to the localization of a defect or to a narrow track in the transverse direction, which makes it possible to increase the accuracy of localization of defects in the transverse direction.

[0024] The terminal transmitting component and terminal receiving components can be located in a common connector block. This allows easy electrical connection of the probe once it is inserted into the holder. Moreover, the use of this probe in existing test systems may not require any adaptation of electrical cables.

[0025] Between the transmitting and receiving components is preferably placed, in order to acoustically decouple them, a partition (acoustic shield) made of a material that absorbs ultrasound, such as cork, foam, etc. In some embodiments, for the same purpose, alternatively or additionally, at least one partition made of an ultrasound absorbing material, for example, a plug, is installed between the transceiver units located adjacent in one row. As a result, cross-talk in the transverse direction can be significantly reduced or eliminated. If there are two or more transceiver units located one behind the other, they can have a common partition that provides acoustic decoupling of the transmitting and receiving components in the transceiver units. This solution reduces the manufacturing costs required for acoustic decoupling.

[0026] For the purpose of acoustic optimization of the probe, each transceiver unit can be equipped with a sound-absorbing element located on the side of the probe opposite to the side that is to be brought into acoustic contact with the surface of the test object. Although each transceiver unit may be provided with its own sound absorbing element, the probe body preferably contains a single sound absorbing element that acts as a sound absorbing element for all transceiver units. One of the results of this implementation is the simplification of manufacture.

[0027] The invention also relates to an ultrasonic system for non-destructive testing of an object in the process of relative movement of the test object and the probe in the direction of testing, which contains one or more probes according to the invention. This system can be, in particular, an ultrasonic testing system for metal plates.

Brief Description of Drawings

[0028] Other advantages and properties of the invention will become apparent from the appended claims and the following description of the preferred embodiments of the invention, taken with reference to the accompanying drawings.

FIG. 1 shows, in plan view, from its active side, an ultrasonic probe according to an embodiment of the invention.

FIG. 2 shows, in section, the probe of FIG. 1 installed in the probe holder.

FIG. 3 is a schematic plan view of a variant with a different arrangement of sound-absorbing baffles.

FIG. 4 schematically, in a plan view, another variant with a different arrangement of sound-absorbing partitions is shown.

FIG. 5 shows, in section, the probe of FIG. 2 with a different sequence of transmitting and receiving components.

Implementation of the invention

[0029] FIG. 1 is a schematic plan view of a probe 100 according to one embodiment of the invention. The probe is shown from its active side, i.e. from the side with which it is brought to the surface of the object to be tested. FIG. 2, the same probe is shown in section in a vertical plane. This probe is intended for use in a fully automatic ultrasonic metal plate testing system that uses a group of nominally identical probes. The probe preferably operates at a nominal frequency of about 4 or 5 MHz and in the illustrated embodiment uses a combination of three transmitting and three receiving ultrasonic transducers, i.e. represents a transceiver probe (transceiver probe).

[0030] The probe preferably uses a milled metal body 110 that has a cross-section as shown in FIG. 1 is substantially rectangular in shape with a width (measured in the transverse direction Q) more than twice the length (measured in the longitudinal direction L). As an example, the width of the case is about 65 mm, while its length (measured in a direction perpendicular to the width) is 24-25 mm. The probe body is open from the side of the active surface 120 (see Fig. 2). On the rear side opposite the active surface, the probe body is closed, except for the conduits for the electrical lines.

[0031] As schematically illustrated in FIG. 2, during the installation and setup of the testing system, the probe 100 is inserted into the holder 200, which, together with a group of other nominally identical probe holders, is fixed to the surface of the testing carriage as part of the testing system. On the underside of the holder 200, facing the test object 290, is a so-called wear sole 210 in the form of a plate made of wear-resistant material such as stainless steel with hard metal parts or hardened steel. For testing, the probe holders are brought to the test object 290 so that the wear-resistant substrates come in contact with the surface of the test object 292 and slide over it if the test object moves relative to the probe holder in the direction of testing 295. In this case, the probe is installed in the probe holder in such a way that the longitudinal direction L of the probe is, as far as possible, parallel to the testing direction 295. Accordingly, the height direction H, orthogonal to the longitudinal and lateral directions, will move away from the surface of the object as far as possible in the vertical direction. The typical travel speed during testing after all probe holders have been connected is, for example, 0.5-1 m / s.

[0032] Wear-resistant substrate 210 has a rectangular notch or lumen 215 that extends from its contact surface 212 to the inner side and is dimensioned in the longitudinal direction L and in the transverse direction Q that the probe 100 can be inserted therethrough with a small clearance relative to the holder probe. At the rear end of the probe, i.e. on the side facing away from the active surface 120, there is a carrier plate 220 which serves to secure and adjust the vertical position of the probe in the probe holder 200. The probe, installed in the holder, is located in such a way that between the planar active surface 120 of the probe and the plane formed by the contact surface 212 of the wear-resistant substrate 210, a so-called coupling gap SP remains, the thickness D of which is constant, as far as possible, along width of the probe and is often about 0.25-0.35 mm. During testing, this gap is filled with a bonding liquid, usually water. Accurate maintenance of the wedge-free bonding gap, especially in the longitudinal direction, is an essential precondition for reliable ultrasonic testing.

[0033] The probe 100 is designed such that it has a relatively uniform high sensitivity without any significant local drops in sensitivity over the entire effective width of the RRC probe testing. For this purpose, in the example under consideration, three nominally identical transceiver units are installed in the internal volume of the probe body, i.e. the first, second and third transceiver units 150-1, 150-2, 150-3. Each of the transceiver units contains a single transmitting component T1, T2, T3 and a single receiving component R1, R2, R3 corresponding to a transmitting component in the same unit. Each of the transmitting and receiving components is provided with a thin rectangular plate of piezoelectric material, which in the case of the transmitting component acts as an emitting ultrasonic transducer, and in the case of the receiving component as an ultrasonic receiving transducer. There are pins not shown on the front and back of the plate. The rectangular plates are oriented parallel to one another in the transverse direction Q and have a mutual inclination in the longitudinal direction, so that a gable configuration (roof-shaped configuration) is formed, mirror-symmetrical about the dividing plane, for example, with an angle of 6 ° (Fig. 2). In the dividing plane (in the plane of symmetry of the configuration in the form of a roof) between the ultrasonic transducers, a dividing wall (partition) 152-1 of a material that absorbs ultrasound is introduced. The partition, preferably made of cork material, serves to acoustically decouple the transmitting and receiving components of the transmitting / receiving unit, so that sound transmission can only take place indirectly, through the material of the test object, which is connected to this unit during testing. The partition also serves to electrically decouple the ultrasonic transducers on the transmitting and receiving sides.

[0034] The presented arrangement of the transmitting and receiving components of the transceiver unit in the test direction can be reversed. Corresponding examples are discussed with reference to FIG. five.

[0035] Above the transceiver components in the inner volume of the housing 110, closed on its rear side, a single sound-absorbing element 260 is placed, which serves to suppress the propagating sound waves from all transceiver units. The free spaces inside the housing between the transmitting components, the receiving components and the baffles are filled with a plastic potting compound to the level of the active surface 120. This ensures a watertight seal for the electrical components of the probe.

[0036] Each of the transceiver units has an effective test width PB, which is measured in the lateral direction and which is somewhat (about 10% -20%) less than the physical extent of the transmitting component T1 and the receiving component R1 in the same direction. To clarify the concept of the effective test width PB1 for the first transceiver unit 150-1, FIG. 1 is a curve E1 that illustrates a typical signal amplitude profile along the component length (measured in the transverse direction Q) for the reference defect FBH-2. Signal amplitude is a measure of sensitivity. This sensitivity profile is characterized by the presence of a rather wide plateau symmetric with respect to the middle of the transceiver unit, a rather high observed signal amplitude with a gentle local drop in sensitivity in the middle of the component, two local maxima М1, М2, shifted to the outer edges of the component, as well as a sharp drop in sensitivity in the immediate vicinity. to the lateral edges of the component. The effective test width PB1 can be determined, for example, in such a way that it corresponds to a region in which the signal amplitude is less than at the local maxima, for example, by no more than 4 dB. Each of the other transceiver units has an effective test width PB2 and PB3, respectively. Effective test widths can be, for example, 20 mm or more. As the test object 290 moves relative to the probe in the test direction 295, each of the transceiver units scans the test track with a width (in the lateral direction) that corresponds to the effective test width for that transceiver unit.

[0037] The transceiver units are positioned relative to each other in such a way that there is a partial overlap in the lateral direction between their effective test widths and between the three test tracks that are scanned by the transceiver units. As a result, scanning can be performed with high sensitivity over the entire total testing width provided by the probe. For this purpose, the transceiver units are installed in two straight rows 155-1, 155-2, located one after the other in the longitudinal direction L and oriented in the transverse direction Q. In this embodiment, the first and third transceiver units 150-1, 150-3 are located in the first row 155-1 with a distance (gap) between them in the transverse direction Q equal to DQ. In this case, the dividing planes between the transmitting components T1, T3 and the receiving components R1, R3, respectively, coincide with one another. The distance DQ between two transceiver units of the same row (measured in the transverse direction) is between 40% and 60% of the size of the transceiver units in that direction (i.e., of their width).

[0038] The second transceiver unit 150-2 is in the second row 155-2, i. E. it is offset longitudinally relative to the first and third transceiver units. This unit is located symmetrically with respect to other transceiver units in such a way that the gap between the transceiver units of the first row is completely bridged. The second transceiver unit 150-2 is located in the transverse direction on both sides of the median plane so that when viewed along the longitudinal direction, the outer parts of this unit are behind the corresponding outer parts of the sender / receiver units located in the first row. As a result, the transceiver units from different (i.e., from the first and second) rows are mutually displaced in the transverse direction Q in such a way that the receiving components of the transceiver units are offset relative to each other, as well as the test tracks scanned by these transceiver units, have an overlapping in zone U1-2 or U2-3. As a consequence, the transceiver units collectively cover the total effective width of the RRC test without any gaps and without a significant drop in sensitivity. The width of the overlapping zones U1-2 and U2-3, measured in the transverse direction Q, is approximately 15-20% of each effective test width PB1, PB2, PB3 provided by the respective individual transceiver units. This ensures, firstly, that testing with high sensitivity is also provided in the area of the tested object corresponding to the specified overlap, and, secondly, that the total effective testing width by means of the probe can be provided by a relatively small number (only three) transceiver units.

[0039] FIG. 1 clearly shows that all transmitter components T1, T2 and T3 of the probe 100 are connected to a common terminal transmitter component AT of the probe. A separate electric line is laid from each receiving component R1, R2, R3 to a separate terminal receiving component AR1, AR2, AR3. The terminal transmitting component AT and the terminal receiving components AR1, AR2 and AR3 are located in a common connector block, so that the probe can be conveniently connected to the electronics of the ultrasonic testing system by plugging it into the corresponding socket.

[0040] There are various possibilities for acoustically and electrically decoupling the transmitting and receiving components. In the embodiment of FIG. 1 and 2, each transceiver unit has a baffle 152-1 installed between the transmitting and receiving components. The partitions are not connected to one another. In the embodiment of probe 300 of FIG. 3, a partition 352 is used, which is common to two transceiver units in the same (first) row. This can simplify the manufacture of the probe. In the embodiment of probe 400 of FIG. 4, a transversely oriented baffle 452 is used and is located between the first-row transceiver units and the second-row transceiver unit. There are also other longitudinally oriented baffles on the narrow sides of the sender / receiver unit. More specifically, the partitions are located on the facing sides of the first row of transceiver units. This provides better rejection of crosstalk in the probe than without cross-barriers.

[0041] In the embodiments of FIGS. 1-4 transmitting components T1, T2, etc. in the composition of various transmitting-receiving units are arranged in such a way that all transmitting components are in mutually parallel planes, at an angle to the LQ plane, due to which all transmitting components from rows arranged in series in the longitudinal direction L radiate in one direction. Therefore, in the embodiment of FIG. 1, three transmitting components T1, T2 and T3 will radiate in the direction obliquely forward during the movement of the probe in the longitudinal direction L.

[0042] FIG. 5 is a cross-section similar to that used in FIG. 2, a modification of the embodiment of FIG. 1, 2. For better clarity, the same designations are used. The only difference compared to the embodiment of FIG. 2 consists in the fact that the transmitting components T1 and T2 of the transmitting / receiving units located one after another in mutually parallel rows are not in mutually parallel planes, but are installed at an angle to each other. Receiving components R1, R2 are arranged in a similar way. One of the effects of this arrangement is that the emitting surfaces of the transmitting components T1, T2 in the composition of the transceiver units located in the longitudinal direction immediately one after the other, are deployed relative to one another and are joined in the zone of mutual overlap in the longitudinal direction. As a result of this mutually deployed position, the main directions of radiation (marked with oblique arrows) are oriented in such a way that the transmitting components emit ultrasound from the inside out. Consequently, the main directions of radiation have oppositely directed components in the longitudinal plane. As a result, compared to the orientation shown in FIG. 1, improved acoustical decoupling of transmitting components in different rows can be provided. Thus, in two-row versions using this reversal, it is possible to install the transmitting components, mutually offset in the longitudinal direction, in the middle region of the probe and, due to their unfolded position, emit sound waves outward from the longitudinal axis.

[0043] Corresponding modifications are also possible with respect to the embodiments of FIG. 3 and 4. For example, in relation to the embodiment of FIG. 3, the arrangement of the transmitting components T2 and the receiving components R2 can be changed so that the transmitting component T2 is directly adjacent to the transmitting components T1 and T3 of two transmit / receive units from another row. For the embodiment of FIG. 4, a corresponding modification can be that the transmitting component T2 is directly adjacent to the partition 452, while the receiving component R2 is displaced outwardly, i.e. located near the probe body.

[0044] As you know, ultrasound testing is based on the difference in the levels of sound waves propagating in different environments. So, these waves experience partial reflection at the boundaries of media with different wave impedances. As the difference in wave impedances increases, the reflected component also increases. A change in acoustic properties at the boundary in a defect or inhomogeneity zone within the test object results in a reflection of the sound pulses emitted by the transmitting component, which arrive at the receiving component as part of the probe. Defects (inhomogeneities) are understood as, for example, cavities, inclusions, cracks or other breaks in the microstructure. The pulse echo method measures the time elapsed between the transmission and reception of a pulse, and the output signal can be generated from measurements of the specified time. In this case, the position and size of the defect (discontinuity) can be determined by comparing such signals with signals from an equivalent reflector (for example, from a standard flat-bottomed hole, FBH), groove or lateral channel. In the case of automated test systems, the information is stored, correlated with the tested object and documented, in various ways, immediately or with delay.

[0045] Tests with conventional 4-channel transceiver probes have shown that these probes have sufficient sensitivity across the entire effective test width for equivalent reflectors up to class FBH-3 (3mm flat bottom hole). However, it has been found that it is often impossible to detect FBH-2 or smaller reference defects with sufficient reproducibility. One of the reasons, with reference to which this limitation of sensitivity is explained, is the presence of zones of reduced sensitivity at the junctions between adjacent receiving components in the same row. The proposed new arrangement of the transceiver units in the probe with overlapping of the tested tracks, i.e. with an effective testing width in accordance with the considered variants of the invention, allows to detect, with high reproducibility, reference defects of the FBH-2 class or smaller (for example, down to FBH-1.2 or FBH-1 or even smaller).

Claims (18)

1. Probe (100) for an ultrasonic system for non-destructive testing of material when the tested object (290) moves relative to the probe in the direction (295) of testing, containing: a housing (110), which defines a longitudinal direction (L) coinciding with the testing direction and a transverse direction (Q) perpendicular to the testing direction, and a group of transceiver units (150-1, 150-2, 150-3), each of which contains a transmitting component (T1, T2, T3) and its corresponding separate receiving component (R1, R2, R3) and sets in the transverse direction (Q ) the effective width (PB1, PB2, PB3) of testing with the provision, in the process of relative movement of the tested object and the probe in the direction of testing, the possibility of testing a track with a width equal to the effective testing width, while: the transceiver units form at least two rows (155-1, 155-2) located in the longitudinal direction (L) one after the other and having an extension in the lateral direction (Q); transceiver units from different rows are mutually displaced in the lateral direction (Q) in such a way that the receiving components (R1, R2, R3) of mutually offset transceiver units are located with mutual overlap in the overlap zone (U1-2, U2-3), so that the set transceiver blocks provide total effective width (PKPB) for probe testing without gaps; all transceiver units are located in the probe body (110), and each of the transmitting components (T1, T2, T3) and receiving components (R1, R2, R3) is equipped with a plate of piezoelectric material and the plates in one transceiver unit are located obliquely with respect to one to another with the formation of a gable configuration, mirror-symmetric relative to the plane separating them, and all transmitting components (T1, T2, T3) are electrically connected to the common terminal transmitting component (AT) of the probe. 2. A probe according to claim 1, characterized in that the overlap zones (U1-2, U2-3) have a lateral width of at least 10%, preferably 20% to 30%, of the effective width (PB1, PB2 , PB3) testing. 3. A probe according to claim 1 or 2, characterized in that adjacent transceiver units (150-1, 150-2) located in the same row (155-1) are separated by a distance (DQ) exceeding 30% of the effective width (PB1 , PB2, PB3) testing for the transceiver unit. 4. A probe according to any one of the preceding claims, characterized in that between the plates, in a plane separating them, a baffle (152-1) of material that absorbs ultrasound is preferably installed. 5. A probe according to any of the previous claims, characterized in that three or four transceiver units (150-1, 150-2, 150-3) are placed in the probe body (110), and the first and third transceiver units are located adjacent to the first row (155-1), and the second transceiver unit (150-2) is located in the second row (155-2) with an offset along the row symmetrical with respect to the first and third transceiver units. 6. The probe according to claim 4 or 5, characterized in that the transceiver units (150-1, 150-2, 150-3) are distributed between the first row (155-1) and the second row (155-2), while the transmitting components of the transceiver units located in different rows are facing one another and are located in the middle region of the probe, and the plates of these components, which are part of the gable structure, are located obliquely relative to each other so that the transmitting components are able, when activated, to emit in directions diverging at an angle to one another. 7. A probe according to any one of the preceding claims, characterized in that its body (110) has a rectangular cross-section. 8. A probe according to any one of the preceding claims, characterized in that each of the receiving components (R1, R2, R3) is electrically connected to a separate terminal receiving component (AR1, AR2, AR3) of the probe. 9. The probe according to claim 8, characterized in that the terminal transmitting component (AT) and the terminal receiving components (AR1, AR2, AR3) are located in a common connector block. 10. A probe according to any of the preceding claims, characterized in that there is a single sound absorbing element (260) inside the probe body (110), which functions as a sound absorbing element for all transceiver units. 11. A probe according to any one of the preceding claims, characterized in that it is provided with at least one partition made of ultrasound-absorbing material, which is located between adjacent transceiver units of the same row. 12. Ultrasonic system for non-destructive testing of an object in the process of relative movement of the test object and the probe in the direction of testing, which contains one or more probes made according to any of the previous paragraphs.

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