JPS62191757A - Method for controlling divided-driving of array type probe - Google Patents

Abstract

PURPOSE:To perform high speed flaw detection by enhancing the repeated frequency of the transmission and reception of an array type probe, by dividing the minute vibrators constituting the array type probe into a plurality of groups and driving the divided groups in parallel under control to perform the ultrasonic scanning of an object to be inspected. CONSTITUTION:Minute vibrators 19-50 are provided to an array type probe 51 and divided into a plurality of groups, for example, each consisting of 8 adjacent vibrators to form a divided parallel driving start group. The minute vibrators are excited by a transmission control part 81 through a pulser 79 and ultrasonic beams 66, 66' are parallelly emitted from each vibrator divided group to be successively transmitted to a steel pipe 65. The scanning ultrasonic waves from the steel pipe 65 are successively received by each vibrator divided group and processed by an adding processing part 84 to be displayed on a display device 86. The transmitting and receiving timing of ultrasonic waves is controlled by an operational processing part 83 and a beam incident angles thetagamma are equally controlled. Because the minute vibrators of the array type probe are divided into a plurality of divided groups to be subjected to driving control in parallel, the repeated frequency of flaw detection is enhanced to enable high speed flaw detection.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in an ultrasonic beam control method for an array probe in an ultrasonic phased array device.

[Conventional technology]

The ultrasonic flaw detection method using an array type probe (hereinafter referred to as the ultrasonic phased array method) is based on the transmission timing of multiple microscopic transducers that make up the array type probe and the reflection signal from the object. By controlling the reception timing,
By superimposing the phases of the ultrasonic signals from each transducer,
Deflect or focus ultrasound waves in a specific direction, or
It is possible to scan at high speed, and detects flaws by detecting reflected signals in a specific direction.

In such an ultrasonic phased array method, when transmitting and receiving ultrasonic waves from an array type probe, multiple micro oscillators making up the array type probe are grouped, and one micro oscillator is Ultrasonic waves are transmitted and received sequentially from one end of the array type probe to the other end while moving one by one.
A known ultrasonic beam control called so-called linear scanning is often used. For example, an ultrasonic beam control method for ultrasonic flaw detection of steel pipes, which is also described in Japanese Patent Application No. 59-140321, uses ultrasonic linear scanning.

FIG. 2 shows an example of steel pipe oblique flaw detection using linear scanning of an ultrasonic beam by the ultrasonic phased array method.

In this figure, an array-type probe 10 composed of small-sized imagers 1 to 9 of Ultrasonic waves are transmitted and received while shifting the beams one by one.In this case, thin ultrasonic beams 11 to 17 deflected in a specific direction α are transmitted and received.
is scanned from one end of the array probe IO to the other end, and ultrasonic signals in the scanning direction are successively received. The deflection angle α is determined based on the refraction angle θr used for flaw detection. When the incident angle of the ultrasonic beam giving the refraction angle θr is θi, the phase of the ultrasonic waves emitted from the three oscillators is controlled so that they are deflected at the deflection angle α, and the ultrasonic beams 11 to 17 are directed to the steel pipe 1.
The information is transmitted and received sequentially toward the surface of the 8.

[Problem that the invention seeks to solve]

When performing linear scanning flaw detection using an array type probe that has the same overall effective size as a normal ultrasonic probe consisting of a single transducer, the former probe has a single transducer. Although it is possible to transmit and receive at a high repetition frequency, the latter array type probe detects the same flaw detection area as the former probe only after repeating transmission and reception many times from one end to the other. That is, in the case of an array type probe, the repetition frequency for transmitting and receiving ultrasonic waves must be low. It is clear that the height of this repetition frequency greatly affects the flaw detection speed when the flaw detection target material is transported continuously over a long period of time. Therefore, depending on the transport speed of the material to be inspected, there may be cases where flaw detection is difficult using the ultrasonic phased array method.

[Means for solving problems]

In transmitting and receiving ultrasonic beams from an array type probe, the present invention separates the divided drive state by dividing and driving the drive start points of the micro oscillators constituting the array type probe into a number of points. The repetition frequency can be increased.

[Effect]

According to the present invention, in linear scanning flaw detection using the ultrasonic phased array method, it is possible to increase the repetition frequency of transmission and reception to the array type probe. By moving the array type probe at high speed over a specimen having a stopped length, high-speed flaw detection can be achieved that is close to the detection speed of a single ordinary ultrasonic probe.

〔Example〕

Hereinafter, a detailed explanation will be given using specific examples.

FIG. 1 is an explanatory diagram of an ultrasonic beam control method during linear scanning using divided driving in an array type probe according to the present invention. Figure 1 (al is an explanatory diagram of the divided drive situation for each micro-oscillator group of the array type probe; Figure 1 (b)
1 is an explanatory diagram simulating a situation in which ultrasonic beams emitted from each micro-oscillator group of an array type probe by split drive are injected into a steel pipe.

Figure 1 (in al, 3211i1 minute 1st axis
The array type probe 51 is composed of eight micro-oscillator groups 52' to 64' and 52' of 52'' to 62''.

The 52" transducer group is used as a divided parallel drive starting group, and the 64'
, 64". This shows that ultrasonic waves are sequentially transmitted and received toward the transducer group of 64".
The steel pipe 65 is driven by the divided parallel drive group of the array probe 51.
Ultrasonic beams 66 to 78.6 are sequentially transmitted toward
6' to 78' are shown, 66" to 78", 6
6'' to 78'' indicate the incident points of the ultrasonic beams transmitted by the divided parallel drive. In this way, by performing flaw detection by driving the array probe 51 in two parts, flaw detection can be performed at twice the repetition frequency compared to conventional linear scanning flaw detection. Figure 3 shows a block diagram of steel pipe flaw detection using an ultrasonic phased array device.

A case will be described in which flaws are detected as a group of eight adjacent micro-vibrators using the array type probe 51 made up of the 32 micro-vibrators 19 to 50 described above in FIG. In Fig. 3, 79 is a pulser for exciting one minute oscillator 19 to 50, 80 is a receiver that receives and amplifies the ultrasonic signal received by minute oscillators 19 to 50, and 181 is the excitation timing of each oscillator. 82 is a reception control unit that controls the reception timing of each transducer, 83 is a calculation processing unit that calculates the transmission and reception timing and controls each part according to the calculation result, and 84 is a reception control unit that controls the reception timing of each transducer. 85 is a display control section for forming an image of the ultrasonic beam scanning cross section, and 86 is a display for displaying this.

First, in the arithmetic processing unit 83, based on the geometrical arrangement of the steel pipe 65 and the array probe 51, and the flaw detection conditions, the transmission timing is set to equalize the incident angles of the ultrasonic beams emitted from each transducer group onto the steel pipe surface. The time and the corresponding reception timing time are calculated. The deflection angle of the ultrasonic beam emitted from each transducer group consisting of the micro transducers 19 to 50 is determined by the calculation result, and the ultrasonic beam is deflected.
The transmission control unit 81 controls the excitation timing of the pulser 79. The signals received by the micro oscillators 19 to 50 pass through a receiver 80, and are controlled by a reception control unit 82 so that the received signals from each oscillator are added according to the calculation results, and these signals are added to an addition processing unit 84. By adding them, it is possible to extract the ultrasonic signal in the deflection direction of the ultrasonic wave.

This kind of operation is carried out in each transducer group 52' to 64', 52'' to 6
4'', 26 ultrasonic beams are scanned by driving 52' and 52'' in parallel and sequentially shifting the ultrasonic beams. Based on the received signals after addition corresponding to each scanned ultrasonic beam, the display control unit 85 displays an image of the ultrasonic beam scanning cross section on the display 86, and compares the flaw detection results with normal linear scanning flaw detection. This can be achieved with twice the repetition frequency compared to the conventional case.

〔Effect of the invention〕

As described above, according to the present invention, in linear scanning flaw detection using an ultrasonic phased array device, the repetition frequency of flaw detection can be increased by the number of divided drives of the array type probe, making it possible to perform faster flaw detection. Become. In the example, a steel pipe is used as the material to be tested, but other plates,
The present invention is also effective for flaw detection on rods, square timbers, etc. Also, the first
Figure (a).

fb) describes the array type probe as being driven in parallel by two divisions, but there is no limit to the number of divisions.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an ultrasonic beam control method during linear scanning with an array type probe according to the present invention (1 drive). Figure 1fbl is an explanatory diagram of the divided drive situation for groups, and is an explanatory diagram simulating the situation in which the ultrasonic beams emitted by the divided drive from each micro-oscillator group of an array type probe are thrown into a steel pipe. Figure 2 is an explanatory diagram showing an example of oblique flaw detection for two or four pipes using linear scanning of an ultrasonic beam using the ultrasonic phased array method, and Figure 3 is a block diagram of steel pipe flaw detection using an ultrasonic phased array device. Applicant Minoru Aoyagi, patent attorney representing Nippon Steel Corporation Procedural amendment (spontaneous) May 8, 1986 Michibe Uga, Commissioner of the Japan Patent Office 1, Indication of the case 1986 patent Application No. 33253 2 Name of the invention Split drive control method for array type probe 3 Relationship with the case of the person making the amendment Patent applicant address 2-6-3 Otemachi, Chiyoda-ku, Tokyo Name (
665) Nippon Steel Corporation Representative Takeshi 1) Yutaka 4, Agent 101 Address No. 4-5 Iwamotocho, Chiyoda-ku, Tokyo, Higashi Building Name (7017) Patent attorney Aoyagi
Minoru 8, Contents of the amendment (1) "As per superimposition," on page 2, line 14 of the specification is amended to "superposition is possible. Therefore." (2) Correct the ``number place'' on page 5, line 4 to ``multiple places.'' (3) Change “52” to 62” on page 6, line 8 of the same page to “52” to
Correct to 64″. (4) Figure 3 of the drawings will be amended as shown in the attached sheet.

Claims (1)

[Claims] The array-type probe includes an array-type probe composed of a large number of micro-oscillators, a pulser that excites the array-type probe, and a receiver that receives signals received by the array-type probe. a transmission control section that controls the transmission timing of ultrasonic waves for each transducer; a reception control section that controls the reception timing of each transducer; and a reception control section that controls the reception signal of each transducer controlled by the reception control section. an addition processing section that performs addition; a display control section that performs control to display an image of a cross section of a test material based on a signal from the addition processing section; a display that displays an image of a cross section of a test material; In an ultrasonic phased array device that consists of an arithmetic processing section that calculates optimal control values for the transmission control section, reception control section, addition processing section, and display control section according to conditions and controls the operation of each section, the array An ultrasonic beam control method characterized by dividing minute transducers constituting a shaped probe into a plurality of groups and driving and controlling the divided groups in parallel to perform high-speed ultrasonic scanning.