JPS6165158A - Ultrasonic flaw detector - Google Patents

Abstract

PURPOSE:To improve measuring operability sharply and to attain more precise measurement by automating the attenuation ratio setting operation of an attenuator to include a decibel value processed by the attenuator always within a highly accurate reading range without manual operation. CONSTITUTION:The arithmetic processing of e=20log c/d is executed on the basis of an output value (c) obtained by A/D converting an analog signal attenuated by the attenuator 6 and a reference value (d) obtained from a reference value oscillation circuit 8 to obtain an attenuation decibel value (e). The calculated attenuation decibel level (e) is compared with a set-up attenuation decibel value (f) obtained from a set-up attenuation decibel value oscillation circuit 10 by a comparator 11. The attenuation ratio of the attenuator 6 is automatically set up and changed by a setting/changing means 12 on the basis of said compared result so that the calculated attenuation decibel value (e) is '0' or less and the set-up decibel value (f) or more, i.e. the value (e) is included within the highly accurate reading range.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an ultrasonic flaw detection device for flaw detection of piping, etc.
In detail, the transmitting probe that projects ultrasonic waves onto the inspected member,
A receiving probe that receives the ultrasonic waves transmitted through the inspected member, an attenuator that attenuates the intensity of the ultrasonic waves received by the receiving probe at a set ratio, and a device that displays the signal from the attenuator on a cathode ray tube. This invention relates to improvements to the ultrasonic flaw detection equipment provided.

[Conventional technology]

Conventionally, in the above-mentioned ultrasonic flaw detection equipment, the attenuation ratio of the attenuator is configured to be changeable by manual operation, and by changing the setting, when reading the signal value from the attenuator as a decibel value on the logarithmic scale on the cathode ray tube, the attenuation ratio is changed. The waveform image was adjusted to position the signal waveform in the high-precision reading range of the logarithmic scale.

[Problem that the invention seeks to solve]

However, as the signal waveform from the attenuator changes over time, it is extremely complicated and difficult to manually set the attenuation ratio of the attenuator one after another while reading the measured values indicated by the waveform. Met.

An object of the present invention is to automate the attenuation ratio setting operation by rationally improving the attenuator setting operation configuration.

[Means for solving problems]

The characteristic configuration of the ultrasonic flaw detection apparatus according to the present invention is based on an A/D converter for a signal from an attenuator, an output value C from the A/D converter, and a reference value d from a reference value transmitting means. Means for calculating the attenuation decibel value e using the following formula %; means for comparing the calculated attenuation decibel value e from the calculation means with the set attenuation decibel value [from the set attenuation decibel value transmitting means; There is provided a means for automatically changing the setting of the attenuation ratio of the attenuator so that the calculated attenuation decibel value e is 0 or less and the set attenuation decibel value is 1 or more, based on the comparison result by the comparison means.・The effects are as follows.

[For production]

In other words, as shown in FIGS. 1 and 2, the analog signal from the attenuator (6), that is, the cathode ray tube (4
) The analog signal value (b) attenuated by the attenuator (6) is sent to the A/D converter (7) to adjust the waveform image.
By digitizing it with the reference value transmitting means (8), an output value C which digitally indicates a value corresponding to the height (X) of the waveform (^) displayed on the cathode ray tube (4) is obtained.
) by substituting the reference value d, which is equal to the upper limit of the CRT human power range, and the output value C into the following equation, e = 20j1! og c/d A negative calculated attenuation decibel value e is obtained which indicates the difference in decibels between the upper limit height xo) of the image area of the cathode ray tube (4) and the height X) of the displayed waveform (A).

Then, an attenuation decibel value f is set as a negative value corresponding to the difference between the upper limit height χ0) of the CRT image area and the lower limit height XL) of the high-precision reading range (Y) of the logarithmic scale on the CRT (4). The attenuation decibel value transmitting means (10) transmits the attenuation decibel value, and the comparison means (11) compares the set attenuation decibel value f with the calculated attenuation decibel value e, and based on the comparison result by the comparison means (11),
When the calculated attenuation decibel value e is less than or equal to O, the set attenuation decibel value is 1.
In other words, the image waveform (A) at each point in time is between the upper limit (xo) of the CRT image area and the lower limit (XL) of the high-precision reading range (Y), that is, the high-precision reading range. The attenuation ratio of the attenuator (6) is automatically changed by the setting changing means (12) so that the attenuator (6) is located within (Y).

C. Effect of the invention] As a result of the above, the image waveform indicating the intensity state of the received ultrasonic wave is
It is possible to always appropriately position the logarithmic scale within the high-precision reading range without any manual adjustment operations, greatly improving measurement operability, and furthermore, it is possible to position the waveform located within the high-precision reading range on the logarithmic scale. Since the measurer can concentrate on reading, more accurate measurements can now be made.

〔Example〕

Next, an embodiment will be described based on FIGS. 1 and 2.

Transmission probe (2) that projects ultrasonic waves onto the inspected member (1)
4, and a receiving probe (3) that receives the ultrasonic waves that have passed through the inspected member (1), and receives the voltage signal (a) from the receiving probe (3). A cathode ray tube (4) is provided to display the intensity state of the ultrasonic wave in a waveform, and a digital display section (5) is provided to digitally display the intensity of the received ultrasonic wave.
This is an ultrasonic flaw detection device that detects flaws in a member to be inspected (1) based on r''a, that is, attenuation information +a of transmitted ultrasonic waves.

An attenuator (6) is provided that attenuates the voltage signal (a) from the receiving probe (3) to a set ratio while taking the corresponding voltage, and the value (b) of the analog voltage signal from the attenuator (6) is When reading the waveform (A) imaged on the cathode ray tube (4) at a proportional height X) on the logarithmic scale on the cathode ray tube (4), the image waveform (8)
) The waveform image can be adjusted by changing the settings of the attenuator attenuation ratio in multiple steps so that it fits within the image area of This is to accurately read the state of change on the cathode ray tube (4).

An A/D converter (
7), and a reference value transmitting circuit (8) which transmits a fundamental voltage signal of a voltage value (d) equal to the upper limit voltage value of the input range of the cathode ray tube (4) by digital. Based on the output voltage value (c) from the converter 11A converter (7) and the reference voltage value (d) from the reference value transmitting circuit (8), the upper limit height of the image area of the cathode ray tube (4) (X,) is determined. An arithmetic circuit (9) is provided which calculates a negative attenuation decibel value (e) indicating the difference in decibels from the height (X) of the displayed waveform (A) using the following equation.

e = 206 ogc/d and set attenuation with a negative value corresponding to the difference between the upper limit height xo) of the CRT image area and the lower limit height XL) of the high precision reading range (Y) of the logarithmic scale on the CRT (4). A set attenuation decibel value transmitting circuit (10) that transmits a voltage signal giving a decibel value (f) is provided, and the set attenuation decibel value (f) and the calculated attenuation decibel value (e) from the arithmetic circuit (9) are provided. A circuit (11) for comparing is provided, and based on the comparison result by the comparison circuit (11),
The attenuation ratio setting changeover switch (6A) in the attenuator (6) is automatically operated so that the calculated attenuation decibel value (e) is 0 or less and the set attenuation decibel value (f) or more (f<e<O). A switching command circuit (12) for switching is provided.

In other words, the attenuator attenuation ratio adjustment for positioning the video waveform (A) within the high-precision reading range (Y) can be performed fully automatically.

Note that the set attenuation decibel value (f) that defines the high-precision reading range (Y) can be changed by manual operation.

The switching command circuit (12) is configured to determine the attenuator attenuation ratio in each switching state and, based on the determination result,
The attenuator setting decibel value (g) indicates how many decihers of received ultrasound intensity the reference voltage value (d) (the upper limit voltage value of the cathode ray tube input range) corresponds to in the switching state before attenuation processing by the attenuator (6). A display H3 (13) includes a switching state discriminating circuit (12A) that calculates the attenuator setting decibel value (g) by table calculation or the like, and numerically displays the attenuator setting decibel value (g) based on a digital output signal from the switching state discriminating circuit (12A). ), so that the measurer can check the cathode ray tube (4) at each measurement point.
The structure is such that it is easy to recognize how many decibels the upper limit height of the image area (Xo) represents.

Further, in order to digitally display the intensity of the received ultrasonic waves on the digital display section (5), the switching state discriminating circuit (
Attenuator setting decibel value given from (12A)
g) (a positive value indicating how many decibels the CRT image area upper limit height Xo) corresponds to) and the calculated attenuation decibel value (e) given from the arithmetic circuit (9) (CRT image area upper limit height xo) The decibel value (k) of the received ultrasound intensity expressed as the height X) of the video waveform (A) can be obtained by adding the negative value corresponding to the difference between the height An adder circuit (14) for calculating is provided, and a display device (58) numerically displays the decibel value (k) of the received ultrasound intensity based on the calculation result of the adder circuit (14);
A printer (5B) that continuously prints out the numerical values.
) is provided in the digital display section (5).

[Another example]

Sending the reference value (d), calculating the attenuation decibel value (e), emitting the set attenuation decibel value (f) (δ, and comparing the calculated attenuation decibel value (e) and the set attenuation decibel value (f)) The specific circuit configuration for performing this can be changed in various ways, and these configurations are collectively referred to as the reference value transmitting means (8), the calculating means (9), and the set attenuation decibel value transmitting means (10). ), and comparison means (11).

In order to automatically change the setting of the attenuation ratio of the attenuator (6) based on the comparison result by the comparison means (11), the attenuation ratio is changed from the maximum side to the minimum side while feeding back the comparison result by the comparison means (11). Alternatively, by sequentially changing from the minimum side to the maximum side, the setting is changed to the optimum damping ratio, or,
The specific form of setting change can be changed in various ways, such as by preliminarily inferring the optimum damping ratio based on the comparison result by the comparison means (11), and then rapidly changing the setting of the damping ratio to the analogous optimum damping ratio. Furthermore, in the various modified forms as described above, the specific operation circuit configuration for switching the attenuation ratio switching configuration in the attenuator (6) based on the comparison result from the comparing means (11) can also be changed in various configurations. These operation circuit configurations are collectively referred to as setting change means (12).

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, with FIG. 1 being a schematic circuit diagram and FIG. 2 being a schematic diagram. (1)...Member to be inspected, (2)...Emitting probe, (3)...Receiving probe, (4)...
... Braun tube, (6) ... Attenuator, (7) ... A/D converter, (8) ...
・Reference value transmitting means, (9)...Calculating means, (1
0)...Setting attenuation decibel value transmitting means, (11
)... Comparison means, (12)... Setting changing means.

Claims (1)

[Claims] A transmitting probe (2) that projects ultrasonic waves onto a member to be inspected (1)
, a reception probe (3) that receives the ultrasound transmitted through the inspected member (1), an attenuator (6) that attenuates the intensity of the ultrasound received by the reception probe (3) at a set ratio;
The ultrasonic flaw detection device is also equipped with a device for displaying the signal from the attenuator (6) on a cathode ray tube (4), and includes an A/D for the signal from the attenuator (6).
Converter (7), output value c from its A/D converter (7)
and a reference value d from the reference value transmitting means (8), a means (9) for calculating an attenuation decibel value e by the following formula e=20logc/d, and a calculated attenuation decibel value e from the calculation means. , setting attenuation decibel value transmitting means (10
) for comparing the set attenuation decibel value f from (11)
), and based on the comparison result by the comparison means (11), the attenuation ratio of the attenuator (6) is automatically changed so that the calculated attenuation decibel value e is less than 0 and greater than the set attenuation decibel value f. An ultrasonic flaw detection device provided with a means (12) for