JPH02115762A - Ultrasonic test equipment - Google Patents

Abstract

PURPOSE:To distinctly discriminate a reflected ultrasonic wave by receiving and transmitting ultrasonic waves by electromagnetic ultrasonic transducers independent of each other and separating a transmitter and a receiver. CONSTITUTION:Electromagnetic ultrasonic transducers 4a and 4b are connected to an ultrasonic test equipment B and are placed on the surface of a material 5 to be examined, and when a transmission pulse is inputted from an ultrasonic transmitter 1 to the transducer 4a, an ultrasonic wave 6 is transmitted into the material 5 to be examined and is propagated in the material 5 while repeating multireflection. the transducer 4b receives the ultrasonic wave 6 and receives a reflected ultrasonic wave 8 due to a defect 7 also. Since the ultrasonic wave 8 is propagated in the opposite direction of the ultrasonic wave 6, it is received by the transducer 4a also. Thus, the reflected ultrasonic wave is distinctly discriminated without an influence of the transmission pulse.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to an ultrasonic flaw detection device used for ultrasonic flaw detection.

(Prior art) Ultrasonic flaw detection is carried out during periodic inspections of nuclear facilities. In order to perform ultrasonic flaw detection, an ultrasonic flaw detection device and an ultrasonic transducer are required. Conventionally, various types of ultrasonic transducers have been proposed. An electromagnetic ultrasonic transducer is known as one of these ultrasonic transducers. Unlike those that use magnetostrictive or electrostrictive elements, this electromagnetic ultrasonic transducer uses Lorentz force to generate ultrasonic waves in the material to be inspected, and is in a non-contact state with the material to be inspected. It has the feature that it can be set. Therefore, even if the surface of the material to be inspected has irregularities, the test can be carried out without any special treatment.

By the way, when carrying out an ultrasonic flaw detection inspection using such an electromagnetic ultrasonic transducer, an ultrasonic flaw detection apparatus A as shown in FIG. 3 is used.

The ultrasonic flaw detection apparatus A shown in FIG. 3 includes an ultrasonic transmitter 1.
Ultrasonic receiver2. Waveform display device 3 and electromagnetic ultrasound 1-
It consists of a transducer 4, and usually these ultrasonic transmitters 1. The ultrasonic receiver 2° waveform display device 3 is combined into one housing, and the electromagnetic ultrasonic transducer 4 is connected by a cable. When inspecting the material 5 to be inspected using this ultrasonic flaw detection device A, the following procedure is performed.

Connect the electromagnetic ultrasonic transducer 4 to the ultrasonic deep wound device [A, place it on the surface of the material 5 to be inspected, and transmit an electric signal from the ultrasonic transmitter 1 to the electromagnetic ultrasonic transducer 4.
Electric signals are converted into ultrasonic signals within the electromagnetic ultrasonic transducer 4, and ultrasonic waves 6 are transmitted into the inspected material 5.

If there is a defect in the inspected material 5, a part of the ultrasonic wave 6 will detect the defect 7.
, and a reflected ultrasound wave 8 is generated. This reflected ultrasonic wave 8 is detected by the electromagnetic ultrasonic transducer 4, converted into an electric signal again, amplified by the ultrasonic receiver 2, and displayed as a pulse F in the waveform display device 3, indicating the presence or absence of defects. This is a judgment-like expression. As shown in Fig. 4(a), when the pulse width of the transmitted ultrasonic pulse 9 is short, even if the thickness of the inspected material is thin, the transmitted ultrasonic pulse 9 and the reflected ultrasonic wave 8 can be clearly identified, but if the pulse width of the transmitted ultrasonic pulse 9 is long, and the thickness of the inspected material is thin, as shown in Fig. 4 (
As shown in b), the transmitted ultrasonic pulse 9 and the reflected ultrasonic wave 8 cannot be clearly distinguished.

Therefore, in order to widen the inspection range to inspect thin plate materials, it is necessary to shorten the pulse width of the transmitted ultrasonic pulse 9.

(Problem to be solved by the invention!a) Since the electromagnetic ultrasonic transducer 4 has poor sensitivity, the ultrasonic deep wound NA configured as described above is difficult to clearly detect the reflected ultrasonic waves 8 from the defect. In addition, it is necessary to use a high-output pulse generator as the ultrasonic transmitter 1 and a high-amplification voltage amplifier as the ultrasonic receiver 2.

Therefore, since the large output pulse is amplified by a voltage amplifier with a high amplification degree, the minute voltage portion of the large output pulse is also greatly amplified. Therefore, the pulse width of the transmitted pulse 9 becomes apparently long, and the reflected ultrasound 8 is hidden within the transmitted pulse, resulting in a problem that the reflected ultrasound 8 cannot be clearly detected.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an ultrasonic flaw detection device that can clearly detect reflected ultrasonic waves 8 without being affected by transmitted pulses 9. .

[Structure of the invention]

(Means for Solving the Problems) In order to solve the above object, in the present invention, two electromagnetic ultrasonic transducers are used, one of which is an electromagnetic ultrasonic transducer for transmitting ultrasonic waves, and the other is an electromagnetic ultrasonic transducer for transmitting ultrasonic waves. It is characterized by being an electromagnetic ultrasonic transducer for transmission.

(Function) Ultrasonic reception and ultrasonic transmission are performed by separate electromagnetic ultrasonic transducers, and the ultrasonic transmitter and ultrasonic receiver can be separated, so that the transmitted pulse is the electromagnetic ultrasonic wave for ultrasonic reception. The ultrasonic wave is not directly input to the transducer, so even if the single reflected ultrasonic wave is amplified by a high-amplification voltage amplifier, the single reflected ultrasonic wave can be clearly detected because it is not affected by the transmitted pulse.

(Example) FIG. 1 shows an example of the present invention. Note that the same parts as in FIG. 3 are denoted by the same reference numerals, and the explanation thereof will be omitted. As shown in FIG. 1, the ultrasonic flaw detection device B has an electromagnetic ultrasonic transducer 4a for transmitting ultrasonic waves connected to an ultrasonic transmitter 1, and an electromagnetic ultrasonic transducer 4b for receiving ultrasonic waves connected to an ultrasonic receiver 2. do. Further, the ultrasonic receiver 2 is connected to a waveform display device 3.

The method of using the ultrasonic flaw detector B is the same as the method of using the ultrasonic flaw detector A. That is, the electromagnetic ultrasonic transducers 4a and 4b are connected to the ultrasonic flaw detector and placed on the surface of the material 5 to be inspected. When an electric signal is transmitted from the ultrasonic transmitter 1 to the electromagnetic ultrasonic transducer 4a, the electric signal is converted into an ultrasonic signal within the electromagnetic ultrasonic transducer 4a, and an ultrasonic wave 6 is transmitted into the inspected material 5. Inspected material 5
If there is a defect inside, a part of the ultrasonic wave 6 is reflected by the defect 7, and a reflected ultrasonic wave 8 is generated. This reflected ultrasonic wave 8 is detected by the electromagnetic ultrasonic transducer 4b, converted into an electrical signal, and amplified by the ultrasonic receiver 2, and displayed as a pulse F in the waveform display device 3, indicating the presence or absence of defects. It will be judged.

Next, the operation of the ultrasonic flaw detection apparatus B will be explained based on FIG.

When a transmission pulse is input from the ultrasound transmitter 1 to the electromagnetic ultrasound transducer 4a, the transmission pulse is converted into an ultrasound signal within the electromagnetic ultrasound transducer 4a, and an ultrasound 6 is transmitted into the inspected material 5.

As shown in FIG. 1, this ultrasonic wave 6 propagates within the inspected material 5 while repeating multiple reflections. As shown in FIG. 1, when the electromagnetic ultrasonic transducer 4b for receiving ultrasonic waves is placed at the point of incidence of the ultrasonic waves 6 on the surface of the inspected material 5, the electromagnetic ultrasonic transducer 4b receives the ultrasonic waves 6. Next, when the ultrasonic wave 6 is reflected by the defect 7 and a reflected ultrasonic wave 8 is generated, the receiving electromagnetic ultrasonic transducer 4.

Unlike ordinary piezoelectric ultrasonic transducers, it has bidirectional sensitivity, so it can also receive reflected ultrasonic waves 8 whose propagation direction is different from that of ultrasonic waves 6. Furthermore, the reflected ultrasound 8 propagates in the opposite direction to the ultrasound 6 and is also received by the electromagnetic ultrasound transducer 4a.

FIG. 2 shows such an ultrasonic reception state. Fig. 2(a) shows the state of ultrasonic pulses in the electromagnetic ultrasonic transducer 4a for ultrasonic transmission, and Fig. 2(b) shows the state of ultrasonic pulses in the electromagnetic ultrasonic transducer 4b for ultrasonic reception. This shows the state of ultrasonic pulses. As can be seen from FIGS. 2(a) and 2(b), the electromagnetic ultrasonic transducer 4b for ultrasonic reception can receive the reflected ultrasonic waves 8 without being affected by the transmitted pulses.

〔Effect of the invention〕

As described above, if the ultrasonic flaw detection device of the present invention is used,
Since the ultrasonic transmission pulse does not affect the reflected ultrasonic waves, the reflected ultrasonic waves can be clearly identified. For this reason,
Even when inspecting thin plate materials, defective locations can be determined accurately, expanding the inspection range. Furthermore, since pulses from defects can be easily determined, inspection time can be shortened.

[Brief explanation of the drawing]

FIG. 1 is a functional block diagram of the ultrasonic flaw detection device of the present invention,
FIG. 2 is a schematic diagram of the waveform that appears on the waveform display device when the ultrasonic flaw detection device of the present invention is used, FIG. 3 is a functional block diagram of a conventional ultrasonic flaw detection device, and FIG. Appears on the waveform display when using an ultrasonic flaw detector. Schematic diagram of ultrasound shape. 1... Ultrasonic transmitter 2... Ultrasonic receiver 3... Waveform display device 4... Electromagnetic ultrasonic transducer 5... Inspected material 6... Ultrasonic wave 7.
...Defect 8...Reflected ultrasound 9.
...Ultrasonic transmission pulse agent Patent attorney Nori Chika Ken Yudo Daishimaru Ken Figure 1

Claims (1)

[Claims] It has two electromagnetic ultrasonic transducers, an ultrasonic transmitter, an ultrasonic receiver, and a waveform display device, and one of the two electromagnetic ultrasonic transducers is electrically connected to the ultrasonic transmitter, and the other is electrically connected to the ultrasonic transmitter. 1. An ultrasonic flaw detection device comprising: electrically connected to an ultrasonic receiver, and the ultrasonic receiver electrically connected to a waveform display device.