JPS6027853A - Ultrasonic wave flaw detector - Google Patents

Abstract

PURPOSE:To enable, ultrasonic divergent scanning within an accurate range even if an incident plane is limited without complicating incident angle control, by allowing an acoustic lens to refract ultrasonic wave from a selected electrode of plural vibrators and allowing the wave to be emitted from the center of a wedge member contacting this lens. CONSTITUTION:When electrodes 35a-35c, etc., out of supersonic vibrator electrodes 35a, 35b... installed on an acoustic lens 34, are selected for excitation, the ultrasonic wave from the electrodes 35a-35c is refracted by the lens 34 and then converges to the center A of the wedge member 32 contacting with the lens 34. Ultrasonic wave is emitted from the center A to a specimen 14 in a convergent manner and even if an incident plane of ultrasonic 15 of the specimen 14 is limited, accurate divergent ultrasonic wave scanning of inside of the specimen becomes available without complicating incident angle control.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sector scan type ultrasonic flaw detection apparatus for detecting flaws in a metallic structural member such as a ship's hull using ultrasonic waves.

For example, to detect welding conditions inside a hull weld using ultrasonic waves, a fan-shaped scanning imaging device using an array sensor II as shown in FIG. 1 is used. The above array type sensor I
I is m number of vibrator electrodes arranged in a horizontal row (Niremen)
,) Z2a.

Z2b... can be seen once, and this vibrator electrode 12a
.

12b... By exciting each with a pulse signal from the pulse generation circuit 13, ultrasonic waves I are generated within the inspected object 14.
Propagate 5. Here, the object 1 to be inspected by this ultrasonic wave 15
The angle of incidence θ for 4 is.

Vibrator electrodes 12a, 12b of array sensor IK
...The timing of exciting each of them, that is, the timing of generating a pulse signal by the pulse generation circuit I3, is set by controlling the control circuit z6, and the incident angle θ of this ultrasonic wave 15 is set as shown by arrow a. By sequentially changing and scanning, the interior of the object to be inspected X4 is detected in a fan shape.

In this case, the ultrasonic wave 1 that scans the object 14 and returns
5 is the vibrator electrode 12 again at the same angle as the above incident angle θ.
a s I 2 b..., this received signal is amplified through the amplification circuit 17%, and the received signal delay circuit 18 transmits the above-mentioned vibrator hl!Z J a @ I
2 Delayed with respect to the excitation timing of b... This delay time control is performed by the control circuit 16, and the received signal after the delay control is added to the adder circuit Z9.
The ultrasonic flaw detection is fully detected by combining the two.

In other words, 1, for example, if a defective portion occurs in the object to be inspected 14, an inspection cross-sectional image is displayed on the display device 20, showing the defect tjlS in the blank area 21 as shown in FIG. It is something that will be done.

However, in the scanning imaging device configured in this way, the transducer electrode 12a of the array sensor II that generates the ultrasonic wave 15 is
, 12b are arranged in a single row in a plano-concave shape.
b'f A plane m which uniformly contacts each of them] 4 peaks are required Q. In other words, 1. For example, if the ultrasonic incident angle of the object to be inspected 14 has a curvature or is unnecessarily narrow, it is very difficult to make the ultrasonic wave 15 sufficiently incident on the object to be inspected 14. Therefore, it is impossible to scan the inside of the object I4 in a fan shape, and control of the ultrasonic incident angle θ with respect to the object I4 is complicated, which is not preferable.

This invention was made in view of the above problems.1
An object of the present invention is to provide an ultrasonic flaw detection device that can perform fan-shaped scanning in a simple and accurate range without making incident angle control complicated, even when the ultrasonic wave incidence surface is very narrow, for example.

That is, the ultrasonic flaw detection device according to the present invention is as follows.

- a wedge member having an arcuate surface on one side; an acoustic lens placed in contact with the entire arcuate surface of this wedge member; A constant number of vibrator electrodes arranged in a row, a means for sequentially selecting and exciting each of the plurality of vibrator electrodes, and a signal k that is sequentially received by the plurality of vibrator electrodes.
and a means for selecting and adding an ultrasonic wave emitted through the acoustic lens when the vibrator electrode is excited?
, it is arranged to concentrate on a part of the surface opposite to the arcuate surface of the wedge member.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 shows its configuration, and this flaw detection device is equipped with an array type sensor 3I. FIG. 4 shows this array type sensor 31 ft, and this sensor 3I has a semicylindrical wedge member 32. This wedge member 32 has an arcuate surface 33 on its upper surface, and an acoustic lens 34 is placed on the arcuate surface 33. This effect lens 3
Reference numeral 4 is set to contact the entire surface of the arcuate surface 33, and a plurality of vibrator electrodes 35a, 35b, . . . are arranged on the surface of this acoustic lens. The vibrator electrodes 35a, 36b, . . . are arranged at right angles to the arc direction of the wedge member.
Pole 35a.

A damper material 36 is provided around the back surfaces of the components 35b, . . . and is surrounded by an envelope 32.

And, the vibrator electrode 35a of this array type sensor 3I,
A plurality of pulse generating circuits 41a, 41bN, . . . in FIG. 3 are connected to 35b, . . . , respectively. This pulse generating circuit 41a.

41b, . . . are m number of vibrator electrodes 35a3, respectively.
This pulse generating circuit 41a supplies a pulse (No. 1) to the electrodes 35a, 35bh, .

A channel selection circuit 42 is connected to a r b @..., and the plurality of vibrator electrodes J 5 a @ 35 b
+...Select each excitation order.

In addition, the vibrator electrode 36m of the upper self-array sensor 3I,
35b, . . . each include a plurality of amplifier circuits 43m,
A reception channel selection circuit 44 is connected via 43b, . The reception channel selection circuit 44 excites the reception signals supplied from the plurality of transducer electrodes 35aj5b, . . . via the amplifiers 43m, 43b, . The receiving channel selection circuit 44 is connected to the display device 2o via the addition circuit I9. Each of the channel selection circuits 42 and 44 includes a control circuit b.
1 & 45 are connected, and the selection order of each is fully controlled.

In other words, when performing ultrasonic flaw detection with flaw detection equipment configured in this way,

For example, three pulse generation circuits 41a to 41c are selected by the control circuit 45, and three of the array sensors 31 are selected.
Only the vibrator electrodes 35a to 35C are excited and driven. As a result, the three vibrator electrodes 35a to 35c are arranged as shown in FIG.
As shown in A), ultrasonic waves 15 are generated and radially propagated toward the transverse object l. In this case, the ultrasonic waves 15 from the upper mouth 1 transducer electrodes 35a to 35c are
4, and is concentratedly radiated from the center A of the surface of the wedge member 32 facing the arcuate surface 33.

Then, from the center H1iA of this wedge member 32,
The ultrasonic wave 15 incident on the body 14Vc is propagated in a radiation range proportional to the selected electrode range as shown by the arrow X.After this, the ultrasonic wave 15 reflected back from the object I4 is , are again received by the respective vibrator electrodes 35a to 35c via the center part A of the wedge member 32,
The signal is supplied to a reception channel selection circuit 44 via amplifiers 43a to 43c in FIG.

Next, the control circuit 45 selects and sets the second pulse generation circuit group 41b to 41d, and excites and drives the vibrator electrodes 35b to 35d in a range shifted by the I vibrator electrode 35a from the previous time. As a result, as shown in Figure 5 ω),
Ultrasonic waves 15 emitted from the transducer electrodes 35b to 35d via the acoustic lens 34 and the center part A of the wedge member 32
starts to propagate to the object Z4 to be inspected in a direction that is shifted by a certain angle [Y] from the previous time.

Thereafter, the ultrasonic wave X5 reflected back from the test object 14 is received by each of the transducer electrodes 35b to 35d again via the central part in the same manner as in the case of emission described above, and the corresponding one is shown in FIG. is supplied to the receiving channel selection circuit 44 via the amplifiers 43b to 43d.
5b, . . . are sequentially selected in a fixed number and excited and driven, the object to be inspected 14 is scanned in a fan-like manner by the ultra-light beam 15 having the central portion A of the wedge member 32 as the radiating point. Then, the reflected reception signal of the ultrasonic wave 15 supplied to the reception channel selection circuit 44 is sent to the addition circuit 19.
The images are combined and displayed on the display device 20 as an @ scan plane image as shown in FIG.

Therefore, if the flaw detection device configured in this way is
A plurality of vibrator electrodes 35 a * J 5 b *...
All of the ultrasonic waves Z5 generated from the acoustic lens 34 are refracted through the acoustic lens 34, and are concentratedly radiated from the center A of the wedge member 32.

For example, even if the ultrasonic wave 15 incident on the object 14 to be inspected is very narrow, it is possible to travel inside the object 14 within an accurate fan-shaped range. Also.

This is because the received signal delay circuit 18 and the like that were conventionally required in FIG. 1 of item n11 can be made unnecessary.

This does not complicate the overall configuration of the device.

As described above, according to the present invention, 1) Even when the ultrasonic incident surface of the object to be inspected is very narrow or has a curvature, the incident angle control can be easily performed without becoming complicated. Furthermore, it becomes possible to scan the inside of the object to be inspected in a fan-like manner within an accurate range. This greatly expands the range of applications for flaw detection equipment.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a fan-shaped scanning video device using a conventional play-type sensor, FIG. 2 is a diagram showing the display state of the display device of the video device, and FIG. 3 is a diagram showing an embodiment of the present invention. FIG. 4 is a diagram showing the configuration of such an ultrasonic flaw detection device, and FIG. FIG. 19... Addition oil path, 20... Display device, 31...
Array type sensor, 32... Wedge member, 33... Arc surface, 34... Acoustic lens, 35a, 35b... Vibrator' cold pole, 41a, 41b... Pulse generating circuit.

Claims (1)

[Claims] a wedge member having an arcuate surface on one surface; an acoustic lens placed in contact with the entire surface of the arcuate portion of the wedge member; means for selecting and exciting each of the multiple number of vibrator electrodes, and sequentially selecting and adding the signals received by the vibrator electrodes of the above-mentioned number of pulls. and means for concentrating the ultrasonic waves emitted through the acoustic lens on a part of the surface of the wedge member facing the arcuate surface VL when the vibrator electrode is excited. Device.