JP5957297B2 - Defect search device, scan device, and defect search method - Google Patents

Description

  The present invention relates to a defect search device, a scanning device, and a defect search method.

  Defects such as scratches occur in objects such as pipes and tanks. For this reason, it is necessary to search for a defect generated in the object. Patent Document 1 discloses a self-propelled flaw detector used for such a search.

JP 2009-128122 A

By the way, in order to search the defect | deletion which arose in the target object, an ultrasonic wave is used, for example.
For example, in the ultrasonic oblique angle flaw detection method, an ultrasonic input / output unit scans in a direction orthogonal to the direction of movement of the self-propelled flaw detector, and a reflected wave due to an ultrasonic wave defect placed in the object at a predetermined angle. The relative distance to the deficit is calculated based on the time until receiving. Thereby, the presence / absence, position, and size of a defect in the scanned range can be obtained. In this case, since it is necessary to scan the input / output unit in the direction orthogonal to the moving direction of the self-propelled flaw detector, the search takes time, but since the ultrasonic waves are reflected on the front and back surfaces of the target, You can search for defects on both the front and back sides of objects.
In the TOFD (Time of Flight Diffraction) method, an ultrasonic input part and an output part are arranged at a predetermined interval on the surface of an object, and ultrasonic waves are modulated by defects when propagating from the input part to the output part. Then, the presence / absence and position of the defect are obtained based on the modulated portion in the detected ultrasonic waveform. In this case, since it is not necessary to scan the input unit and the output unit, the search time is greatly shortened, but lateral waves propagate on the surface of the target object that the input unit and the output unit contact, A dead zone in which a defect in a range up to a depth of several millimeters cannot be searched is generated, and a defect on the surface of the target object may not be suitably searched.

  As described above, an object defect search apparatus is required to search for defects on both sides of an object in a short time.

The defect search apparatus according to the present invention is provided with a moving body that moves on the surface of an object to be searched for defects, and is immovable on the moving body, and detects reflected waves by introducing ultrasonic waves from the surface of the object. a plurality of input-output unit, a storage unit and an amplifier for amplifying a detection signal output from each of the plurality of input and output portions, the respective detection signals amplified by the amplifier accumulates, stores the waveforms of the detection signals, An analysis unit that analyzes a waveform of each detection signal stored in the storage unit and searches for a defect of the object. Then, a plurality of input and output portions, respectively, a detection signal including a reflected wave component of ultrasonic waves reflected by dispersing inputs the ultrasonic spread dispersed within the object to the object so as to overlap each other output To do. Amplifiers, each detection signal is included in, is amplified by each logarithmic amplifier reflected wave component of ultrasonic waves reflected and dispersed. The analysis unit analyzes the waveform of each detection signal output from the plurality of input / output units at the same timing and stored in the storage unit based on the reflected wave component in the overlap of the ultrasonic dispersion ranges, Search for the location of the defect.

Preferably, the moving body, a plurality of input and output unit is provided side by side in a direction intersecting the moving direction of the moving body, a plurality of input-output unit, for one output unit is the object even without least enter the ultrasonic obliquely Te, analysis unit, the waveform of the detection signal stored in the storage unit, analyzed by apertures synthesis, to search for the position of the defect of the object, and good.

  Preferably, the input / output unit may disperse and spread the ultrasonic wave in the object by inputting an ultrasonic wave of 2 MHz or more and 5 MHz or less to the object.

A scanning device according to the present invention is a scanning device used in a device for searching for damage to an object for which a defect is to be searched, and is provided on a moving body that moves on the surface of the object, and is immovably provided on the moving body. A plurality of input / output units that detect reflected waves by inputting ultrasonic waves from the surface of the object, and an amplifier that amplifies each detection signal output from each of the plurality of input / output units. Then, a plurality of input and output portions, respectively, a detection signal including a reflected wave component of ultrasonic waves reflected by dispersing inputs the ultrasonic spread dispersed within the object to the object so as to overlap each other output To do. Amplifier is amplified by each logarithmic amplifier the reflected wave component that is included in the detection signals. The position of the defect of the object is searched by analyzing the waveform of each detection signal output from the plurality of input / output units at the same timing based on the reflected wave component in the overlapping of the ultrasonic dispersion ranges.

In the defect search method according to the present invention, an ultrasonic wave is input to an object from each of a plurality of input / output units that are immovably provided on a moving body that moves on the surface of the object to be searched for defects. each stored a measurement step of detecting reflected waves, a storing step of storing waveform of the detection signal in the storage unit each of the detection signals accumulated and outputted from each of the plurality of input-output unit, the storage unit by the An analysis step of analyzing the waveform of the detection signal to search for a defect in the object. In the measurement step, ultrasonic waves that are dispersed and spread within the object are input to the object from a plurality of input / output units so as to overlap each other , and a detection signal including a reflected wave component of the ultrasonic waves that is dispersed and reflected Is output. The storage step, the connection log amplifier between the input and output unit and the storage unit, and accumulates the amplified respectively reflected wave component that is included in the detection signals. In the analysis step, the waveforms of the detection signals output from the plurality of input / output units at the same timing and stored in the storage unit are analyzed based on the reflected wave components in the overlap of the ultrasonic dispersion ranges, Analyze the location of the defect.

  In the present invention, it is possible to search for defects on both sides of an object in a short time.

1 is a schematic configuration diagram of an ultrasonic automatic oblique angle flaw detector according to an embodiment of the present invention. FIG. 2 is a schematic block diagram illustrating a control system and a processing system of the ultrasonic automatic oblique inspection device of FIG. 1. It is explanatory drawing of the dispersion | distribution range of the ultrasonic wave of each probe of the 1st probe of FIG. 1, a 2nd probe, and a 3rd probe. It is a figure which shows the correspondence of the dispersion | distribution range of the ultrasonic wave by the several probe of FIG. 1, and the detectable range of the defect | deletion by aperture synthesis. It is a flowchart which shows an example of the flaw detection operation | movement by the ultrasonic automatic bevel angle flaw detector of FIG. It is explanatory drawing of an example of the search process of the damage | wound (deletion | deletion) by opening synthetic | combination processing.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram of an ultrasonic automatic oblique inspection device 1 according to an embodiment of the present invention.
FIG. 2 is a schematic block diagram showing a control system and a processing system of the ultrasonic automatic oblique flaw detection apparatus 1 of FIG.
1 and 2 is a device that searches for defects such as scratches on an object 61 such as a gas pipe or a gas tank using ultrasonic waves.
Since the ultrasonic wave is used for the search, the ultrasonic automatic bevel flaw detector 1 can search for a defect in a state where the gas pipe and the gas tank are filled with gas.
FIG. 1 shows a welded object 61.
A range of a predetermined width from the weld line L1 is called a welded portion W1.
A range about three times as large as the welded portion W1 is referred to as a flaw detection range W2.

  1 includes a scanner controller 2, a scanner device 3, a flaw detector 4, and a computer device 5.

The scanner device 3 irradiates the object 61 with ultrasonic waves while traveling and moving on the surface S0 of the object 61.
The scanner device 3 includes, for example, a housing 11, a pair of rubber-equipped magnetic tires 12, an encoder 13, a plurality of probes such as a first probe 14, a second probe 15, and a third probe 16. And having.

The housing 11 has a rectangular frame shape along the surface shape of the flaw detection surface (here, the surface S0) of the object 61. Within the frame of the housing 11, the first probe 14, the second probe 15, and the third probe 16 are arranged in a line. A pair of rubber-equipped magnet tires 12 is disposed outside the frame of the housing 11. The magnet tire 12 is rotatable in a direction perpendicular to the arrangement direction of the plurality of probes.
Thereby, the scanner device 3 can move the surface S0 of the object 61 in a direction perpendicular to the arrangement direction of the plurality of probes in a state where the magnet tire 12 is attracted to the surface S0 of the object 61. For example, as shown in FIG. 1, when the welding part W1 of the target object 61 is extended linearly, it can move along the linear welding part W1.
In a gas pipe, a gas tank, or the like, the scanner device 3 is moved along the linear welded portion W1 to search for defects such as scratches.
The encoder 13 rotates according to the magnet tire 12 and outputs a pulse signal corresponding to the amount of rotation of the magnet tire 12.

The scanner controller 2 is connected to the scanner device 3 and the computer device 5.
The scanner controller 2 controls the operation of the scanner device 3. For example, input / output of ultrasonic waves by a plurality of probes is controlled based on a pulse signal input from the encoder 13.
The scanner controller 2 generates travel data 19 indicating the amount of movement of the scanner device 3 from the pulse signal input from the encoder 13 and outputs it to the computer device 5.

The first probe 14 includes, for example, a holder 21, a waveguide member 22, and a diaphragm 23.
The holder 21 fixes the diaphragm 23 and the waveguide member 22 to the housing 11.
The waveguide member 22 has, for example, a cylindrical shape. The waveguide member 22 is in contact with the surface S0 of the object 61 at the bottom surface.
The diaphragm 23 is disposed, for example, on the upper surface of the waveguide member 22.
The diaphragm 23 is of a small size in the propagation direction of, for example, 5 to 10 mm square ultrasonic waves. Thereby, the first probe 14 inputs the ultrasonic wave of the transverse wave generated by the diaphragm 23 from the waveguide member 22 to the object 61.
The frequency of the ultrasonic waves is, for example, 2 to 5 MHz. By inputting such relatively low frequency transverse ultrasonic waves obliquely to the object 61, the ultrasonic waves are easily dispersed and spread within the object 61. For example, when the waveguide member 22 is made of acrylic and the object 61 is a metal gas pipe, the waveguide member 22 is brought into contact with the object 61 at an angle inclined by about 68.5 degrees to To 5 MHz ultrasonic waves are refracted at the contact surface according to Snell's law and easily spread in a relatively wide range within the object 61.
The diaphragm 23 detects a reflected wave transmitted from the object 61 to the waveguide member 22 and outputs a detection signal (echo signal) including a waveform component of the reflected wave to the flaw detector 4.
The diaphragm 23 detects not only the reflected wave in the straight direction of the ultrasonic wave, but also the reflected wave due to the defect of the ultrasonic wave that is obliquely spread from the incident direction, which has not been used in the conventional automatic ultrasonic oblique inspection method. To do.
Note that a water absorbent sheet may be sandwiched between the waveguide member 22 and the object 61 so that the ultrasonic wave can easily propagate between the waveguide member 22 and the object 61. Water can be retained on the contact surface by the water absorbent sheet, and transmission loss of ultrasonic waves can be reduced.

The first probe 14 is connected to the scanner controller 2, vibrates the diaphragm 23 based on the input of the output instruction signal from the scanner controller 2, and outputs pulsed ultrasonic waves.
Therefore, in the detection signal by the diaphragm 23 after outputting the ultrasonic wave, the reflected wave component of both the front surface S0 and the back surface S1 of the target object 61 and the target object 61 with respect to the ultrasonic wave spreading in the target object 61 are included. And a reflected wave component due to deficiency.

  The configurations of the second probe 15 and the third probe 16 are the same as those of the first probe 14, and a description thereof will be omitted.

The flaw detector 4 is connected to the scanner device 3, the scanner controller 2, and the computer device 5.
The flaw detector 4 includes, for example, a plurality of log amplifiers including a first log amplifier 31, a second log amplifier 32, and a third log amplifier 33, and a plurality of ADCs including a first ADC (Analog to Digital Converter) 34, a second ADC 35, and a third ADC 36. And a storage unit 37.
In the flaw detector 4 used in the ultrasonic automatic oblique angle flaw detection method, a linear amplifier is used instead of the log amplifier. In the ultrasonic ultrasonic oblique flaw detection method, the probe is scanned in a direction perpendicular to the moving direction, and a reflected wave from a predetermined direction from which the ultrasonic wave is output is detected from a detection signal from the diaphragm 23 of the probe. This is because it is enough.

The first log amplifier 31 is connected to the diaphragm 23 of the first probe 14. The first log amplifier 31 amplifies the detection signal from the diaphragm 23.
Unlike a linear amplifier, a log amplifier compresses a signal with a wide dynamic range to an equivalent decibel value. Functions as a logarithmic converter. For example, in the example of FIG. 6 to be described later, the detection signal of the diaphragm 23 including at least a reflected wave component of −30 dB to −50 dB can be converted into a signal having an amplitude of 0 to 5 V, for example, an input / output level of the IC. I just need it.
The log amplifier only needs to be capable of sufficient sensitivity correction.

The second log amplifier 32 is connected to the diaphragm 23 of the second probe 15.
The third log amplifier 33 is connected to the diaphragm 23 of the third probe 16.
The configurations of the second log amplifier 32 and the third log amplifier 33 are the same as those of the first probe 14, and a description thereof will be omitted.

The first ADC 34 is connected to the first log amplifier 31. The first ADC 34 converts the output signal of the first log amplifier 31 into a digital value. The first log amplifier 31 outputs a digital value to the storage unit 37.
The second ADC 35 is connected to the second log amplifier 32. The second ADC 35 converts the output signal of the second log amplifier 32 into a digital value. The second log amplifier 32 outputs a digital value to the storage unit 37.
The third ADC 36 is connected to the third log amplifier 33. The third ADC 36 converts the output signal of the third log amplifier 33 into a digital value. The third log amplifier 33 outputs a digital value to the storage unit 37.

The storage unit 37 is, for example, a semiconductor memory or a hard disk device.
The storage unit 37 accumulates and stores digital values input from the first ADC 34. As a result, the storage unit 37 stores the waveform data of the entire waveform of the detection signal including the reflected wave component detected by the diaphragm 23 of the first probe 14 as the first waveform data 38.
The storage unit 37 stores the waveform data of the entire waveform of the detection signal including the reflected wave component detected by the diaphragm 23 of the second probe 15 as the second waveform data 39.
The storage unit 37 stores the waveform data of the entire waveform of the detection signal including the reflected wave component detected by the diaphragm 23 of the third probe 16 as the third waveform data 40.

The computer device 5 includes an I / O (Input / Output) port 41, a display unit 42, a CPU (Central Processing Unit) 43, a memory 44, and a system bus 45 for connecting them.
The I / O port 41 is connected to the flaw detector 4 and the scanner controller 2 by a communication cable according to, for example, the IEEE (Institute of Electrical and Electronics Engineers, Inc.) 802.3 standard.
The display unit 42 displays the flaw detection result for the object 61.
The display unit 42 displays the flaw detection result by, for example, a cross-sectional view of the object 61 viewed in the three orthogonal axes.
The CPU 43 executes a program stored in the memory 44.
Thereby, the analysis unit 46 is realized in the computer device 5.
The program stored in the memory 44 may be stored before shipment of the computer device 5 or stored after shipment. Even if the program stored in the memory 44 after shipment is downloaded from a server device via a communication medium such as the Internet, the program is stored in a computer-readable recording medium such as a CD-ROM (Compact Disc-Read Only Memory). You may install what was recorded.

FIG. 3 is an explanatory diagram of the ultrasonic dispersion range of each probe of the first probe 14, the second probe 15, and the third probe 16.
FIG. 3A shows the ultrasonic dispersion range of the first probe 14.
FIG. 3B shows the ultrasonic wave dispersion range of the second probe 15.
FIG. 3C shows an ultrasonic wave dispersion range of the third probe 16.
In these drawings, the front surface S0 of the target object 61, the back surface S1 of 0.5 skip, the virtual surface S2 of 1.0 skip, so that it can be easily understood that the ultrasonic waves diffuse and travel in the target object 61. A 1.5-skip virtual back surface S3 is shown.
The virtual surface S2 is obtained by mapping the surface S0 with the back surface S1 as a reference.
The virtual back surface S3 is obtained by mapping the back surface S1 with the virtual surface S2 as a reference.
Although the gas pipe is cylindrical and the gas tank is spherical, in the following description, a flat object 61 will be described as an example in order to simplify the description.

As shown in FIG. 3A, the first probe 14 is arranged in contact with the surface S0 of the object 61.
The ultrasonic waves generated by the diaphragm 23 of the first probe 14 enter the target object 61 from the surface S0 of the target object 61 through the waveguide member 22. The ultrasonic waves incident on the object 61 are dispersed and spread in the object 61. When there is no damage, the ultrasonic wave is first reflected on the back surface S1 of the object 61, then reflected on the front surface S0, and further reflected on the back surface S1.
Therefore, for example, the detection signal of the diaphragm 23 corresponding to the section from the timing T11 to the timing T12 in FIG. 3A includes the reflected wave component reflected at the welded portion W1 or the flaw detection range W2 of the object 61. .
The reflected wave component at the same timing of the detection signal includes, for example, a reflected wave component by the first path L2 and a reflected wave component by the second path L3 in FIG. A reflected wave component in a range A1 having the same distance from the first probe 14 is included as a reflected wave component at the same timing.
When a defect such as a flaw occurs in the welded portion W1 or the flaw detection range W2 of the object 61, the timing from the timing T11 to the timing T12 for all waveforms of the detection signals of the diaphragm 23 of the first probe 14 is obtained. The section includes a large reflected wave component. A peak due to the reflected wave component is formed.
In the first waveform data 38, for example, all waveform data of detection signals up to 1.0 skip is recorded.

As shown in FIG. 3B, the second probe 15 is arranged in contact with the surface S0 of the object 61 at a position farther from the first probe 14 with respect to the welded portion W1 of the object 61. Is done.
When a defect such as a flaw occurs in the welded portion W1 or the flaw detection range W2 of the object 61, the timing from the timing T21 to the timing T22 for all the waveforms of the detection signals of the diaphragm 23 of the second probe 15 is obtained. The section includes a large reflected wave component.
In the second waveform data 39, for example, all waveform data of detection signals up to 1.5 skips are recorded.

As shown in FIG. 3C, the third probe 16 is disposed in contact with the surface S0 of the object 61 at a position farther than the second probe 15 with respect to the welded portion W1 of the object 61. Is done.
When a defect such as a flaw occurs in the welded portion W1 or the flaw detection range W2 of the object 61, the timing from the timing T31 to the timing T32 for all waveforms of the detection signals of the diaphragm 23 of the third probe 16 is obtained. The section includes a large reflected wave component.
In the third waveform data 40, for example, all waveform data of detection signals up to 1.5 skips are recorded.

FIG. 4 is a diagram illustrating a correspondence relationship between the ultrasonic dispersion range by the plurality of probes in FIG. 1 and the defect detectable range by aperture synthesis.
FIG. 4A is a stack of FIGS. 3A to 3C.

  Then, as shown in FIG. 4B, for the surface S0 of the object 61, the reflected wave component of the first probe 14 reflected by the virtual surface S2 (1.0 skip), and the first The reflected wave component in which the ultrasonic waves of the two probes 15 are reflected on the virtual surface S2 (1.0 skip) and the ultrasonic waves of the first probe 14 are reflected on the virtual surface S2 (1.0 skips). And a reflected wave component.

The aperture synthesis method is included in the detection waveforms of the plurality of diaphragms 23 by utilizing the difference in the time required for the reflected waves from the same object to reach the plurality of diaphragms 23 arranged at different positions. This is a method of comparing a plurality of flaws adjacent to each other by comparing reflected wave components.
In addition, the position and size of each scratch can be accurately calculated by the aperture synthesis method.

  Therefore, with respect to the surface S0 of the object 61, a plurality of reflected wave components can be obtained as shown in FIG. The number, position and size of each defect can be calculated accurately.

As shown in FIG. 4C, for the back surface S1 of the object 61, the reflected wave component in which the ultrasonic wave of the first probe 14 is reflected by the back surface S1 (0.5 skip), and the second A reflected wave component in which the ultrasonic wave of the probe 15 is reflected on the back surface S1 (0.5 skip) and a reflected wave component in which the ultrasonic wave of the third probe 16 is reflected on the back surface S1 (0.5 skip). Then, the reflected wave component obtained by reflecting the ultrasonic wave of the third probe 16 on the virtual back surface S3 (1.5 skip) is obtained.
Therefore, for the surface S0 of the object 61, the number of defects is determined by the aperture synthesis method for all the ranges of the welded portion W1 or the flaw detection range W2 from which a plurality of reflected wave components are obtained as shown in FIG. The position and size of each defect can be accurately calculated.

  FIG. 5 is a flowchart showing an example of a flaw detection operation performed by the automatic ultrasonic oblique inspection device 1 of FIG.

When searching for a defect in the object 61, as shown in FIG. 1, the scanner device 3 is disposed on the surface S 0 of the object 61 and travels and moves on the surface S 0 of the object 61.
The scanner device 3 outputs a pulse signal from the encoder 13 in accordance with the movement. The scanner controller 2 determines the movement of the scanner device 3 based on the input of the pulse signal (step ST1).

When it is determined that the scanner device 3 has moved by a predetermined amount, the scanner controller 2 outputs travel data 19 indicating the amount of movement or destination of the scanner device 3 to the computer device 5 (step ST2).
The CPU 43 of the computer device 5 stores the travel data 19 in the memory 44.

After outputting the travel data 19, the scanner controller 2 outputs a search instruction signal to the first probe 14 (step ST3).
In the first probe 14, the diaphragm 23 outputs pulsed ultrasonic waves to the object 61, and the diaphragm 23 detects the reflected wave. In the flaw detector 4, the first log amplifier 31 amplifies the detection signal of the diaphragm 23, the first ADC 34 converts it into a digital value, and the storage unit 37 accumulates the digital value. When the storage unit 37 accumulates data for a predetermined time, the entire waveform data of the flaw detection range W2 by the reflected wave of the first probe 14 at the current position of the scanner device 3 is stored as the first waveform data 38. The

After the measurement by the first probe 14 is completed, the scanner controller 2 outputs a search instruction signal to the second probe 15 (step ST4).
In the storage unit 37, all waveform data of the flaw detection range W <b> 2 by the reflected wave of the second probe 15 at the current position of the scanner device 3 is stored as second waveform data 39.

After the measurement by the second probe 15 is completed, the scanner controller 2 outputs a search instruction signal to the third probe 16 (step ST5).
In the storage unit 37, all waveform data of the flaw detection range W <b> 2 due to the reflected wave of the third probe 16 at the current position of the scanner device 3 is stored as third waveform data 40.

When the above measurement processing is completed, the analysis unit 46 of the computer apparatus 5 acquires and analyzes the first waveform data 38, the second waveform data 39, and the third waveform data 40 from the storage unit 37 of the flaw detector 4 (step). ST6).
The analysis unit 46 analyzes the plurality of waveform data by aperture synthesis processing.
Thereby, the presence / absence of a defect such as a scratch at the position of the scanner device 3 indicated by the traveling data 19 is obtained.

After analyzing the defect by the aperture synthesis process, the analysis unit 46 generates display data indicating the number of defects and the position and size of each defect.
The analysis unit 46 outputs the generated display data to the display unit 42.
The display unit 42 displays the display data (step ST7).
On the display unit 42, for example, a flaw detection result screen for displaying a defect color-coded in a cross-sectional view of the object 61 viewed in three orthogonal axes is displayed.

The ultrasonic automatic oblique flaw detection apparatus 1 in FIG. 1 repeatedly executes the process in FIG. 5 every time the operator moves the scanner apparatus 3.
On the display unit 42, defects such as scratches on the object 61 are displayed in real time.

Next, an example of aperture synthesis processing will be described.
FIG. 6 is an explanatory diagram of an example of a scratch (deletion) search process by the aperture synthesis process.
FIG. 6A is an explanatory diagram of a relative position between the probe and the defect of the back surface S1 of the object 61.
FIG. 6A shows four positions of the probe, that is, a first position P1, a second position P2, a third position P3, and a fourth position P4.
FIG. 6B is a characteristic diagram of an example of the level of the detection signal of the reflected wave component in 0.5 steps corresponding to the relative position between the probe and the defect of the target 61.
The upper row shows the relative distance between the probe and the defect.
The lower level is the level of the detection signal of the reflected wave component by the diaphragm 23 of the probe.
The characteristics shown in FIG. 6B are as follows: the standard test piece SAB-A1 has a refraction angle of 68.5 °, an incident point of 6.5 mm, a frequency of 4 MHz, a diaphragm 23 having a size of 5 × 10 mm, and −12 dB. This is an example when the range is 62 ° to 80 °.

FIG. 6C shows the first waveform data 38 by the first probe 14 at the first position P1 near the defect.
FIG. 6D shows the second waveform data 39 by the second probe 15 at the fourth position P4 far from the defect.
These waveform data are all waveform data. The horizontal axis represents time with reference to the timing at which ultrasonic waves are output from the diaphragm 23, for example.
The reflected wave component due to the defect in FIG. 6A is included in the waveform data at a timing corresponding to the relative distance.

In this case, the analysis part 46 performs the analysis process of FIG.6 (E), for example.
In the analysis process of FIG. 6E, the analysis unit 46 performs sensitivity correction for each beam path of each probe in order to prevent a decrease in detection sensitivity due to diffusion loss and scattering attenuation.
For example, standard test piece STB-A2 series or RB-41 No. 2 to correct.
The flaw detection sensitivity may be a sensitivity obtained by matching the echo height of the vertical hole having a diameter of 4 mm and a depth of 4 mm with the H line.

Specifically, the analysis unit 46 first determines the waveform of the timing corresponding to the relative distance for the first waveform data 38 of FIG. 6C in order to determine whether or not the position of FIG. cut.
And it correct | amends based on the characteristic view of FIG. 6 (B) memorize | stored in the memory 44. FIG.
Here, assuming that the H-line level is −30 dB, the analysis unit 46 corrects the level of the cut-out waveform data by −12 dB so that −42 dB in FIG. 6B is set to −30 dB.
When the level of the cut-out waveform data after correction is equal to or higher than the L line level, for example, the analysis unit 46 detects a defect.
The detection level of the scratch may be an echo height 12 dB lower than the echo height of the vertical hole having a diameter of 4 mm and a depth of 4 mm, which is matched with the H line.
Since the detection signal of the diaphragm 23 is amplified by the first log amplifier 31, the level of the waveform actually recorded in the first waveform data 38 is different from the level of the detection signal by the diaphragm 23. . Therefore, the analysis unit 46 detects the loss in consideration of the amplification characteristic of the first log amplifier 31.

Similarly, the analysis unit 46 cuts out the waveform of the timing corresponding to the relative distance from the second waveform data 39 in FIG. 6D and corrects it based on the characteristic diagram in FIG.
In this case, the analysis unit 46 corrects the level of the clipped waveform data by −10 dB so that −40 dB in FIG. 6B is set to −30 dB.
When the level of the cut-out waveform data after correction is equal to or higher than the L line level, for example, the analysis unit 46 detects a defect.
Since the detection signal of the diaphragm 23 is amplified by the second log amplifier 32, the level of the waveform actually recorded in the second waveform data 39 is different from the level of the detection signal by the diaphragm 23. . Therefore, the analysis unit 46 detects the loss in consideration of the amplification characteristic of the second log amplifier 32.

When a defect is detected together, or when a defect is detected on the other hand, the analysis unit 46 performs aperture synthesis processing.
For example, the analysis unit 46 compares the maximum values of the two pieces of waveform data that have been cut out, and specifies the number of defects present in the range to be analyzed, the position and size of each defect.

The analysis unit 46 executes the above processing for each section for the flaw detection range W2.
The analysis unit 46 specifies the number, position, size, and range of damage on both sides and inside of the object 61 existing in the flaw detection range W2.

As described above, in this embodiment, the probe provided in the scanner device 3 that moves on the surface S0 of the object 61 for searching for a defect inputs the ultrasonic waves in the object 61 to the object 61, The reflected wave component of the ultrasonic wave reflected by the defect such as is detected.
At this time, the probe inputs 4 MHz ultrasonic waves to the object 61. The ultrasonic waves spread and spread within the object 61.
Note that even 2 MHz ultrasonic waves or 5 MHz ultrasonic waves are dispersed and spread within the object 61. Ultrasonic waves of 2 MHz or more and 5 MHz or less are dispersed and spread within the object 61.
Further, the log amplifier amplifies the reflected wave component of the ultrasonic wave dispersed and reflected, which is included in the detection signal of the diaphragm 23 of the probe. The log amplifier amplifies both the minute reflected wave component and the large reflected wave component of the dispersed ultrasonic waves.
Therefore, by analyzing the waveform of the detection signal after amplification by the analysis unit 46, it is possible to search for a defect in a range where the ultrasonic waves are dispersed and spread.
A defect can be searched for over a wide range without scanning the probe in the direction intersecting the moving direction of the scanner device 3 as in the ultrasonic automatic oblique angle flaw detection method. Not only defects in a single direction but also defects in a wide range can be searched.

In the present embodiment, the ultrasonic wave input to the object 61 by the probe is reflected on both the front surface S0 and the back surface S1 of the object 61. The diaphragm 23 of the probe detects this reflected wave component.
Therefore, it is possible to search for defects on both sides of the object 61.
In the present embodiment, it is possible to search for defects on both sides of the object 61 in a short time.

Moreover, the analysis part 46 of this embodiment analyzes by an aperture synthesis method using several waveform data.
Therefore, the number and positions of defects can be accurately searched for defects existing in a certain range even though ultrasonic waves are dispersed and spread within the object 61. It is possible to accurately search for the number and position of defects in a region where the ultrasonic wave dispersion ranges overlap in the object 61. The number and positions of defects can be accurately searched for on both sides of the object 61 searched in a short time.

Thus, this embodiment has the following effects.
As in the TOFD method, flaw detection can be performed by scanning in one direction, so that the flaw detection time is shortened and the construction period can be shortened.
Since the pulse reflection method is used, the opening scratches on the inner and outer surfaces of the object 61 can be detected extremely well.
By performing the aperture synthesis method, the position of the flaw can be specified with high accuracy.
Since water is held on the contact surface between the probe and the object 61, there is very little loss of sound.
The reliability of flaw detection results can be improved by recording all waveforms using a log amp.
Since the flaw detection result is displayed as a three-directional image, the flaw detection result can be easily confirmed.
The inspection time can be shortened by using the magnet tire 12 as a drive wheel.

  The above embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications or changes can be made without departing from the scope of the invention.

For example, in the above embodiment, the scanner device 3 has three probes.
In addition to this, for example, the scanner device 3 may have two probes or four or more probes. In addition, the plurality of probes may be arranged in one row in the scanner device 3 or may be arranged in a plurality of rows.

In the above embodiment, in the scanner device 3, the plurality of probes of the first probe 14, the second probe 15, and the third probe 16 are arranged on one side of the weld line L <b> 1 of the object 61. Has been.
In addition to this, a plurality of probes may be arranged on both sides of the weld line L1. For example, three probes may be arranged on the right side and three on the left side of the weld line L1. The plurality of probes may be arranged, for example, in a line so as to be symmetrical with respect to the welding line L1.
The plurality of probes on the right side of the weld line L1 inspects the right side of the weld line L1. The plurality of probes on the left side of the weld line L1 inspects the left side of the weld line L1. Thus, by moving the scanner device 3 once along the weld line L1, it is possible to obtain all waveform data for detecting the welded portion W1 and the flaw detection range W2 for the weld line L1.

  In the above embodiment, the first probe 14, the second probe 15, and the third probe 16 all input ultrasonic waves obliquely to the object 61. In addition to this, for example, the first probe 14 may input an ultrasonic wave straight, and the second probe 15 and the third probe 16 may input diagonally. Even in this case, the analysis unit 46 can accurately search for the number and positions of the defects in the region where the ultrasonic dispersion ranges overlap.

In the above embodiment, the flaw detector 4 is provided with the first log amplifier 31 and the first ADC 34 separately.
In addition, for example, the first log amplifier 31 may amplify the input detection signal and convert it to a digital value. In this case, the first log amplifier 31 may be connected to the recording unit 37. The same applies to the second log amplifier 32 and the third log amplifier 33.
The flaw detector 4 is provided with a pair of log amplifiers and ADCs, and a selector is provided between the log amplifier and the first probe 14, the second probe 15, and the third probe 16. A pair of log amplifiers and ADCs may be used in a time-sharing manner by the first probe 14, the second probe 15 and the third probe 16.

1 Ultrasonic automatic oblique angle flaw detector (defect search device)
2 Scanner controller 3 Scanner device (moving body)
4 Flaw Detector 5 Computer Device 14 First Probe (Input / Output Unit)
15 Second probe (input / output unit)
16 Third probe (input / output unit)
31 1st log amp (log amp)
32 Second log amp (log amp)
33 Third log amp (log amp)
37 Storage Unit 46 Analysis Unit 61 Object S0 Surface

Claims (5)

A moving object that moves on the surface of the object to be searched for defects;
A plurality of input / output units that are provided immovably on the moving body and detect reflected waves by introducing ultrasonic waves from the surface of the object;
An amplifier for amplifying each detection signal output from each of the plurality of input / output units;
Storing each detection signal amplified by the amplifier, and storing a waveform of each detection signal;
An analysis unit for analyzing the waveform of each detection signal stored in the storage unit and searching for a defect in the object;
Have
Wherein the plurality of input-output unit, said each includes reflected wave component of the ultrasonic waves reflected and dispersed with inputs to said object within said object so as to overlap each other the ultrasonic wave spreads dispersed in Output detection signal,
The amplifier, the reflected wave component contained in the respective detection signals amplified by each logarithmic amplifier,
The analysis unit outputs a waveform of each detection signal output from the plurality of input / output units at the same timing and stored in the storage unit based on the reflected wave component in the overlap of the ultrasonic dispersion ranges. Analyzing and searching for the position of the defect of the object,
Defect search device. Wherein the movable body, said plurality of input output unit is provided side by side in a direction intersecting the moving direction of the moving body,
Wherein the plurality of output portions, one of said input and output unit even without less inputs the ultrasonic obliquely to the object,
The analysis unit, the waveform of the stored detection signal in the storage unit, analyzed by apertures synthesis, to search for the position of the defect of the object,
The defect search apparatus according to claim 1. The input-output unit, by inputting a and following the ultrasound 5MHz or more 2MHz to the object, thereby spread by dispersing the ultrasound within the object,
The defect search apparatus according to claim 1 or 2. A scanning device used in an apparatus for searching for damage to an object for which a defect is searched,
A moving body that moves on the surface of the object;
A plurality of input / output units that are provided immovably on the moving body and detect reflected waves by introducing ultrasonic waves from the surface of the object;
An amplifier for amplifying each detection signal output from each of the plurality of input / output units;
Have
The plurality of input-output unit, said each includes reflected wave component of the ultrasonic waves reflected and dispersed with inputs to said object within said object so as to overlap each other the ultrasonic wave spreads dispersed in Output detection signal,
The amplifier, the reflected wave component contained in the respective detection signals, amplified by the logarithmic amplifier,
The position of the defect of the object is analyzed based on the reflected wave component in the overlap of the ultrasonic dispersion ranges, with respect to the waveforms of the detection signals output from the plurality of input / output units at the same timing. Searched by
Scanning device. Measurement in which ultrasonic waves are input to the object from each of a plurality of input / output units provided immovably on a moving body that moves on the surface of the object to be searched for a defect, and a reflected wave is detected by the input / output unit. Steps,
A storage step of storing each detection signal output from each of the plurality of input / output units and storing the waveform of each detection signal in a storage unit,
An analysis step of analyzing the waveform of each detection signal stored in the storage unit and searching for a defect in the object;
Have
Wherein the measurement step, the plurality of input-output unit to the object, the spread and dispersed within the object type ultrasound so as to overlap each other, dispersed reflected wave component of has been the ultrasound reflected and it outputs the detection signal including,
Wherein in the storing step, the connection log amplifier between the input and output unit and the storage unit, the reflected wave component contained in the respective detection signals and accumulates the amplified respectively,
In the analysis step, the waveforms of the detection signals output from the plurality of input / output units at the same timing and stored in the storage unit are based on the reflected wave components in the overlap of the ultrasonic dispersion ranges. Analyze and analyze the position of the defect of the object,
Missing search method.

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