JPH0926417A - Ultrasonic flaw detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to accurately and stably read a flaw echo height by disposing a magnet on the surface in contact with a material to be inspected. SOLUTION: An electromagnet switch b3 is operated to turn off an electromagnet, an operation knob a1 is operated to send an ultrasonic pulse 4 from a vibrator b2, and an ultrasonic probe B is moved along the surface of a material C to be inspected. Simultaneously, a flaw detecting graphic form 1 displayed on a display unit a1 is observed, and the presence of a flaw C1 is confirmed. When the flaw C1 is detected, it is displayed on the form 1. In order to accurately read the maximum echo height of the echo 1b, the switch b3 is closed. Thus, the probe B is fixed to the surface of the material C to be inspected by a predetermined magnetic force. The beam path and the echo height are read and recorded in this state. The switch b3 is operated again to turn off the electromagnet, the probe B is moved along the surface of the material C to be inspected, and other flaw is detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic flaw detector used for nondestructive inspection.

[0002]

2. Description of the Related Art As is well known, there is an ultrasonic flaw detector as a device for inspecting an internal state of an object to be inspected without destroying the object. Further, conventionally, an ultrasonic flaw detector for nondestructively inspecting the state inside the metal has been used as the inspection object.

An ultrasonic flaw detector of this type includes an ultrasonic probe for transmitting an ultrasonic pulse and receiving an echo obtained by reflecting the ultrasonic pulse on a flaw inside the object to be inspected,
It comprises an ultrasonic flaw detector that controls the transmission of ultrasonic pulses and displays the received echo. When inspecting the inside of an object to be inspected using this ultrasonic flaw detector, the inspector holds the ultrasonic probe in his hand and sequentially moves it while making contact with the surface of the object to be inspected. The position and size of flaws existing inside are detected.

In this case, a distance (hereinafter referred to as a beam path) to a reflection mark is displayed as a waveform (hereinafter, a flaw detection pattern) on a display provided in the ultrasonic flaw detection device, and an inspector is not able to make this flaw detection pattern. Recognize echo (hereinafter referred to as flaw echo). When the inspector finds this flaw echo, that is, the flaw, the inspector holds the ultrasonic probe by hand and fixes it, and measures the position and size of the beam without reading the accurate beam path and echo height. Then, the measurement result is recorded on a sheet or the like. After that, the ultrasonic probe is moved again to detect that the ultrasonic probe has not been moved, and the ultrasonic probe is pressed and fixed again by hand,
The operation of reading the beam path and the echo height is repeated.

[0005]

By the way, in the above-described ultrasonic flaw detector, the inspector fixes the ultrasonic probe on the surface of the object to be inspected by holding it by hand, and the flaw echo is detected from the flaw detection pattern of the display. The position and size of the flaw are measured by reading the beam path length and echo height of the. In this case, the inspector should hold the ultrasonic probe with one hand and read the beam path and echo height of the flaw echo from the flaw detection pattern on the display with the other hand and write the read value on the paper. become. Therefore, the force of the inspector pressing the ultrasonic probe in such a state does not have a constant pressing force. In this case, since the transmission loss amount of ultrasonic waves on the flaw detection surface fluctuates due to this fluctuation of the pressing force, the flaw echo height displayed on the display fluctuates, and the inspector must read the flaw flaw height accurately. There was a problem that I could not do it.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an ultrasonic flaw detector capable of reading a flaw echo height in an accurate and stable state.

[0007]

In order to solve the above-mentioned problems, an ultrasonic flaw detector according to claim 1 transmits an ultrasonic wave to a metal as an object to be inspected, and the ultrasonic pulse is reflected. In an ultrasonic flaw detector for detecting flaws existing inside the inspected object based on the obtained reflected wave, while transmitting an ultrasonic pulse to the inspected object, ultrasonic flaw detecting means for receiving the echo, Control means for transmitting an ultrasonic pulse from the ultrasonic flaw detection means and for displaying the echo received by the ultrasonic flaw detection means on a display means, and a contact surface of the ultrasonic flaw detection means with an object to be inspected It is characterized in that a magnet is provided in the.

According to a second aspect of the present invention, there is provided an ultrasonic flaw detector according to the first aspect, wherein the magnet is an electromagnet having a coil wound around it, and the ultrasonic flaw detection means turns on / off a current passing through the coil. It is characterized by having an operator for turning it off.

[0009]

According to the ultrasonic flaw detector of the present invention, the ultrasonic probe means is fixed to the surface of the object to be inspected made of metal by the magnetic force of the magnet.

According to the ultrasonic flaw detector of claim 2,
The electromagnet is turned ON / OFF by operating the operation element,
The ultrasonic probe means can be easily attached to and detached from the object to be inspected.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a diagram showing a schematic configuration of the ultrasonic flaw detector of this embodiment. In this figure, reference numeral A is an ultrasonic flaw detector of the ultrasonic flaw detector, B is an ultrasonic probe for transmitting ultrasonic pulses and echoes of the ultrasonic pulses, and C is a metallic inspection object. For example, it is a welded part of steel or the like.

The ultrasonic flaw detector A is equipped with an indicator a1 for displaying the flaw detection pattern 1 and an operation knob a2 for making various settings, and the ultrasonic flaw detector A is provided with an ultrasonic probe through a probe cable 2 and a power cable 3. It is connected to child B. On the other hand, the ultrasonic probe B is composed of a housing b1, a transducer b2 for transmitting ultrasonic pulses and receiving echoes of ultrasonic pulses, and an electromagnet switch b3.

Here, as shown in FIG. 1, the ultrasonic probes B-1 and B-2 are formed in a box shape or a cylindrical shape, and the contact surface with the object C to be inspected is rectangular or It is circular. The contact surface b4 is made of a resin such as acrylic, and the electromagnet b is provided on the outer periphery of the contact surface b4.
5 to b8 are arranged so as to be embedded. Although not shown, these electromagnets b5 to b8 are integrated inside the housing b1, and a coil (not shown) is wound around a part thereof. One end of this is connected to the electromagnet switch b3,
By turning on / off the electromagnet switch b3,
The current supplied from the ultrasonic flaw detector A via the power cable 3 is configured to flow in the coil.

The vibrator b2 vibrates by the voltage supplied through the probe cable 2 to generate an ultrasonic pulse 4. Further, the transducer b2 detects an echo 5 received by being reflected by the flaw c1 existing inside the inspected portion C of the ultrasonic pulse 4 transmitted by itself, and converts it into an electric signal. The ultrasonic flaw detector A displays this electric signal as flaw detection pattern 1 on the display a1.

Next, using the ultrasonic flaw detector described above,
A method for detecting the flaw c1 existing inside the inspection object C will be described. First, the inspector uses the electromagnet switch b3.
To turn off the electromagnet and operate the operation knob a.
1 is operated to bring the ultrasonic pulse 4 from the transducer b2, and the ultrasonic probe B is sequentially moved along the surface of the inspection object C. At the same time, the flaw detection pattern 1 displayed on the display a1 is observed to confirm the presence of the flaw c1. That is, when the flaw c1 is detected, the flaw c1 is displayed as the flaw echo 11b in the flaw detection figure 1 on the display a1 as shown in FIG.

Here, it is possible to calculate the position and size of the flaw c1 from the flaw detection figure 1 displayed on the display a1, and if the flaw echo 1b corresponds to the flaw c1, the inspector: In order to accurately measure the position and size of the flaw c1, the beam path and echo height of the flaw echo 1b must be accurately read.

That is, the inspector operates the electromagnet switch b3 to turn on the electromagnet in order to accurately read the maximum echo height of the flaw echo 1b. As a result, the ultrasonic probe B is fixed to the surface of the inspection object C by a constant magnetic force. In this state, the inspector reads the beam path length and the echo height and records them on a sheet or the like.
When the recording is completed, the electromagnet switch b3 is operated again to turn off the electromagnet, and the ultrasonic probe B is sequentially moved along the surface of the inspection object C in the same manner as described above to detect other flaws. To do.

[0018]

As described above, according to the ultrasonic flaw detector of the present invention, the following effects can be obtained. (1) Since the ultrasonic flaw detection means is always fixed to the object to be inspected by a magnetic force with a constant force, variations in the flaw detection result are greater than when the inspector holds the ultrasonic flaw detection means by hand and fixes it. Is reduced. (2) Since the ultrasonic flaw detection means is fixed to the inspection object, it is possible to easily acquire flaw data. (3) Since the electromagnet can be turned on / off by operating the operator, the mounting position of the ultrasonic flaw detection means can be easily changed.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of an ultrasonic flaw detector according to the present invention.

FIG. 2 is a perspective view showing a configuration of an ultrasonic probe in the ultrasonic flaw detector of the present invention.

[Explanation of symbols]

 A Ultrasonic flaw detector a1 Display a2 Operation knob 1 Detection pattern 1a Transmission pulse 1b Flaw echo 1c Beam path 1d Echo height B Ultrasonic probe b1 Housing b2 Transducer b3 Electromagnetic switch b4 Acrylic plate b5 to b8 Electromagnet C Inspected object c1 flaw 2 flaw detection cable 3 power cable 4 ultrasonic pulse 5 echo

Claims (2)

[Claims] 1. An ultrasonic wave is transmitted to a metal as an inspection object,
An ultrasonic flaw detector for detecting a flaw existing inside the inspection object based on a reflected wave (hereinafter referred to as an echo) obtained by reflecting the ultrasonic pulse, and transmitting the ultrasonic pulse to the inspection object. Along with, an ultrasonic flaw detection means for receiving the echo, and a control means for transmitting an ultrasonic pulse from the ultrasonic flaw detection means and displaying the echo received by the ultrasonic flaw detection means on a display means, An ultrasonic flaw detector, wherein a magnet is arranged on a contact surface of the ultrasonic flaw detector with the object to be inspected. 2. The magnet is an electromagnet having a coil wound around it, and the ultrasonic flaw detection means is provided with an operator for turning on / off a current passing through the coil. Ultrasonic flaw detector.