JPH06331605A - Ultrasonic inspection device - Google Patents

Abstract

PURPOSE:To realize an ultrasonic inspection device which not need resetting of a delay time for enlarged display even if a water temperature is changed. CONSTITUTION:An ultrasonic inspection device having an elevating function on and under the water surface is provided with a tank 3 having an inflow port 3a, a temperature sensor 7 for measuring a water temperature provided in the neighborhood of the inflow port 3a, a corresponding table 9a for water temperature and sound speed and a calculating means for modifying a delay time t0 set according to the ratio between a first speed t0 acquired corresponding to the water temperature from the table 9a when setting the delay time and a second speed of the current water temperature so as to acquire it as a second time t1, and a wave form of an ultrasonic echo is enlarged and displayed according to the timing delayed by the second time t1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic inspection apparatus, and more particularly to an ultrasonic inspection apparatus for ultrasonically measuring a work through water or the like and displaying an echo waveform for inspection.

[0002]

2. Description of the Related Art FIG. 3 shows an example of a waveform of an ultrasonic echo measured by a conventional water immersion type ultrasonic inspection apparatus.
(A) is an example of a waveform when the water temperature is 20 ° C., where T is a launch echo corresponding to the ultrasonic wave transmitted from the probe to the work into the water, and S is the ultrasonic wave reflected on the surface of the work. Is a surface echo corresponding to, and B is a bottom echo corresponding to the ultrasonic waves reflected on the back surface of the work. A portion of the waveform corresponding to the work is provided for observation for inspection. Therefore, the delay time t0 is set. Then, in the so-called fixed gate mode, the display of the echo waveform during the delay time t0 is suppressed with reference to the timing of the launch echo T, and the time t2 thereafter, that is, between the front surface echo S and the back surface echo B, is dealt with. The displayed waveform is enlarged.

[0003]

In such a conventional ultrasonic inspection apparatus, the echo waveform during the delay time t0, which is unnecessary to be displayed in response to ultrasonic wave propagation in water, is excluded from the display target. However, the ultrasonic wave, which is an ultrasonic medium, has a different ultrasonic wave propagation velocity (hereinafter referred to as “sound velocity” in this specification) depending on the temperature. Therefore, when the water temperature changes, the position of the echo may shift and the front echo S and the back echo B may fall outside the display range (t2) (FIG. 3).
(Refer to the waveform example at the water temperature of 40 ° C. in (b)).

However, in the so-called surface gate mode in which the surface echo is used as a reference, such inconvenience does not occur. However, not all the inspections are required only in the surface gate mode, and in many cases, the fixed gate mode is unavoidable depending on the measurement conditions. Even in the surface gate mode, when the surface echo S is used as a reference and a predetermined time is delayed from the reference, the same problem occurs.

Therefore, in such a case, in order to enlarge and display the waveform of the necessary portion, the delay time must be reset every time the temperature changes to some extent. This is inconvenient and inconvenient from the viewpoint of inspection efficiency. An object of the present invention is to solve the above-mentioned problems of the prior art, and to realize an ultrasonic inspection apparatus that does not require resetting of the delay time for enlarged display even if the water temperature changes. is there.

[0006]

The structure of the ultrasonic inspection apparatus of the present invention for achieving the above object is the same as in the immersion type ultrasonic inspection apparatus having a function of raising and lowering the water surface as an ultrasonic medium. A water tank having a water inlet, and a temperature sensor provided in the water tank near the inlet to detect the temperature of the water poured into the liquid tank from the inlet;
A table showing the correspondence relationship between temperature and sound velocity for the water, and a time set as a delay time for enlarged display of ultrasonic echoes as a set delay time (first time), and when this setting is made The sound velocity associated with the temperature detected by the temperature sensor in the table is set as the set velocity (first velocity), and is associated with the temperature detected by the temperature sensor when the ultrasonic echo to be displayed is measured by the table. When the sound velocity is the measurement speed (second speed), the set delay time is multiplied by the ratio of the set speed (first speed) and the measurement speed (second speed). The set delay time (first speed) is set according to the set speed (first speed) and the measurement speed (second speed).
And a calculation means for obtaining the corrected result time as a correction delay time (second time), between the timing of the launch echo and the correction delay time (second time). Is a method for enlarging and displaying the waveform of the ultrasonic echo in accordance with the timing delayed from the predetermined reference timing by the correction delay time (second time) by suppressing the display start and starting the display after the lapse. Is. Instead of the table, other corresponding means such as a function equivalent to the table may be provided and the sound velocity obtained by this means may be used according to the temperature detected by the temperature sensor.

[0007]

In the ultrasonic inspection apparatus of the present invention having such a configuration, the display position is specified by setting the delay time for the convenience of the apparatus configuration, but the set delay time that takes a set fixed value. Instead, the ultrasonic echo is enlarged and displayed according to the correction delay time that takes a value that is corrected for each measurement according to the temperature and speed of sound of water. This allows
Once the delay time is set and the physical position for enlarged display is specified, even if the water temperature changes and the sound velocity of water changes after that, the position almost corresponding to the specified position is It is a target for enlarged display.

Moreover, since the temperature sensor is provided near the inflow port to detect the temperature of the inflow water based on the water surface up / down function, it is possible to quickly follow the change in the water temperature. In other words, it is possible to minimize the degree to which the correspondence between the position and time that matched at the time of setting deviates due to changes in water temperature, and after that, the correspondence at the time of setting regarding position and time is almost always maintained. To be done. As a result, it is possible to prevent undesired changes in the display position. Therefore, even if the water temperature changes, it is not necessary to reset the delay time for enlarged display.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows a schematic diagram of an ultrasonic inspection apparatus. Here, 1 is a water tank which is a part of the water surface raising and lowering mechanism, 2 is a float which is a part of the water surface raising and lowering mechanism, 3 is a water tank in which ultrasonic measurement is performed, 4 is a workpiece to be inspected, 5 is An ultrasonic probe, 6 is a flaw detector section for sampling ultrasonic echo data via the probe 5 and sending it to the controller 9, 7 is a temperature sensor, and 8 is water temperature data for sampling to the controller 9 via the temperature sensor 7. A thermometer for sending, 9 is a controller mainly composed of MPU, and 10 is a display for displaying an echo waveform under the control of the controller 9.

The bottoms of the water tank 1 and the water tank 3 are connected to each other by piping, and the heights of the water surfaces thereof are the same. When the float 2 that is vertically movable in the water storage tank 1 is vertically driven under this condition, the water surface of the water storage tank 1 moves up and down, and accordingly, the water surface of the water tank 3 also moves up and down. Thereby, the water surface up / down function is achieved. An inflow port 3a is provided at the bottom of the water tank 3, and the above-mentioned piping is connected thereto. Therefore. When the float 2 descends, the water from the water storage tank 1 flows into the water tank 3 through the inflow port 3a.

Further, inside the water tank 3, a temperature sensor 7 for detecting the temperature of the water in the water tank 3 is provided. The temperature sensor 7 is provided in the vicinity of the inflow port 3a, and is particularly fixed at a place where it is easy to receive the water poured into the water tank 3 from the inflow port 3a. An accurate water temperature can be quickly detected by detecting the temperature of running water at this position using the water surface up / down function.

Although not shown in detail, the controller 9 is a computer system which is connected to the flaw detector 6, the thermometer 8, the display 10 and the like through an interface and has an inspection program and a table 9a in the memory. is there. By executing the inspection program having the setting mode and the measurement display mode, the flaw detector 6 is controlled, the ultrasonic echo waveform data is input from the flaw detector 6, and the water temperature data is input from the thermometer 8. , A part of the input waveform data is enlarged and displayed on the display 10. Table 9a
For water as an ultrasonic medium consists of accurate sound velocities of 1 ° C. from 0 ° C. to 63 ° C. The table 9a shows the correspondence between the temperature and the sonic velocity over the temperature range that can be normally used.

The operation of the ultrasonic inspection apparatus having such a configuration will be described. First, the inspection program is executed under the setting mode to set the enlarged display position of the echo waveform. This position setting is also performed in the unit of time because of the convenience of the device in which the gate of the flaw detector 6 is set in the unit of time. Specifically, a time t0 indicating the timing to start the enlarged display with a delay of a predetermined time from the reference timing of the launch echo T or the like and a time t2 indicating the display time width are set. This time t0 corresponds to the set delay time (first time), and these times t0 and t2 are stored in the memory. Further, the temperature detected by the temperature sensor 7 at this time is 2
When the temperature is 0 ° C., the speed of sound corresponding to the water temperature of 20 ° C. in the table 9a, that is, 1482.66 m / s is stored in the memory as the set speed (first speed).

Next, the inspection program is executed in the measurement display mode to perform ultrasonic measurement and enlarged display of the echo waveform. In this ultrasonic measurement, the flaw detector section 6 sends a launch pulse to the probe 5, and in response to this, an ultrasonic wave is transmitted from the probe 5 into the water, which is reflected by the work 4 and the reflected ultrasonic wave is transmitted to the probe 5. The flaw detector section 6 samples via the, and the controller 9 inputs the data of this echo waveform. Further, the enlarged display of the echo waveform is performed by displaying on the display 10 the data of the echo waveform from the time t2 delayed from the timing t1 based on the timing of the ejection pulse of the flaw detector 6 as a reference. Be seen.

Here, the time t2 is already set in the setting mode, but the time t1 is undecided. Therefore, before the waveform display, the inspection program performs the following. The temperature detected by the temperature sensor 8 at this time is input. The same temperature is 20 ° C. immediately after the setting mode. The sound velocity corresponding to this temperature is obtained from the table 9a, and this sound velocity, ie 1482.
The measurement speed is 66 m / s. Then, the time t0 also stored is multiplied by the ratio of the stored set speed and the speed of sound, that is, 1.0. The resulting value (1.0 × t0) is used as the correction delay time (second time). Thus, the inspection program also serves as a calculation unit that corrects the set delay time based on the ratio of the measurement speed and the set speed, and outputs the corrected result as the corrected delay time.

The corrected delay time is used as a specific value of the delay time t1 until the above-mentioned display start.
Since the temperature is 20 ° C. and is the same as the temperature in the setting mode, the speed ratio is 1.0, so that the specific value of the time t1 matches the time t0. Further, the display position of the echo waveform does not change at the same temperature. Therefore, the echo waveform at the position set in the setting mode is enlarged and displayed on the display 10 (see the waveform diagram in FIG. 2A), and this displayed waveform is observed to inspect the first work.

In the same manner, the work is changed one after another and the inspection is repeated. In the meantime, the water temperature changes due to changes in the outside temperature, heat generation from the device, and the like. As a specific example, the measurement display when the water temperature reaches 40 ° C. will be described. The ultrasonic measurement of this work is performed, the data of the echo waveform is input to the controller 9, and the temperature detected by the temperature sensor 8 at this time is also input. The inspection program uses the speed of sound corresponding to this temperature of 40 ° C in the table 9a.
And the sound velocity, that is, 1529.18 m / s is set as the velocity during measurement.

Then, the stored set speed 148
The ratio of 2.66 m / s to the measured speed of 1529.18 m / s, or 0.97, is stored at time t0.
Hang on. The resulting value (0.97 × t0) is used as the correction delay time (second time), and the delay time t until the start of display is t.
It is used as a concrete value t1 ′ of 1. Therefore, the enlarged display of the echo waveform is performed by displaying on the display 10 the data of the echo waveform during the time t2 from the time point delayed by the time t1 ′ from the timing of the ejection pulse of the flaw detector 6 as a reference. Done.

The water temperature is 40 ° C. and the water temperature is 20 ° C. in the setting mode.
Since the sound speed is different, the speed ratio is 0.97, and the time t1 ′ does not match the time t0 and is a short value. On the other hand, as the sound velocity increases, the echo waveform also shrinks along the time axis. This ratio is also equal to the speed ratio 0.97. Therefore, the echo waveform enlarged and displayed from the time point delayed by the time t1 ′ does not change its display position even if the water temperature changes because the fluctuation on the time axis is canceled by the correction of the delay time.

Therefore, the echo waveform at a position substantially corresponding to the position set in the setting mode is enlarged and displayed on the display 10 (see t2 portion of the waveform diagram in FIG. 2B), and this display waveform is observed to The inspection of the workpiece at that time is performed. Therefore, regardless of changes in the water temperature, as long as the workpieces are of the same type, inspections can be performed one after another without resetting the delay time for enlarged display. Although boiling water is generally used as the ultrasonic medium, the present invention is effective even when another liquid is used. Further, the invention is not limited to the fixed gate mode in which the launch echo is used as the reference timing, but is also effective in the surface gate mode in which the surface echo is used as the reference timing.

[0021]

As can be understood from the above description, according to the ultrasonic inspection apparatus of the present invention, in the ultrasonic inspection apparatus having the function of raising and lowering the water surface, a water tank having an inlet and a portion provided near the inlet are provided. A temperature sensor for measuring the water temperature, a correspondence table between the water temperature and the sonic speed, and a ratio between the first speed and the second speed of the current water temperature when the delay time is set, which is obtained from the table in correspondence with the water temperature. And a calculation unit that corrects the delay time set as above and obtains it as a second time, and the waveform of the ultrasonic echo is enlarged and displayed according to the timing delayed by the second time. This eliminates the need to reset the delay time for enlarged display even if the water temperature changes. As a result, there is an effect that the operation is easy and the inspection efficiency is improved.

[Brief description of drawings]

FIG. 1 is a schematic view of an embodiment of the ultrasonic inspection apparatus having the configuration of the present invention.

FIG. 2 is a waveform example for explaining the operation.

FIG. 3 is an explanatory diagram of waveforms of ultrasonic echoes measured by a conventional water immersion type ultrasonic inspection apparatus.

[Explanation of symbols]

 1 Water Tank 2 Float 3 Water Tank 4 Work 5 Ultrasonic Probe 6 Flaw Detector 7 Temperature Sensor 8 Thermometer 9 Controller 10 Display

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Teru Morita 650 Jinrachi-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Engineering Co., Ltd. (72) Ichio Endo 650 Kintate-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery In Engineering Co., Ltd. (72) Inventor, Hajime Mizutani 650, Kazunachicho, Tsuchiura City, Ibaraki Prefecture Hitachi Construction Machinery Engineering Co., Ltd.

Claims (1)

[Claims] 1. A wet ultrasonic inspection apparatus, such as a water immersion type, having a function of raising and lowering the liquid surface of an ultrasonic medium such as water; and a liquid tank such as a water tank having an inlet for the ultrasonic medium, A temperature sensor provided in the vicinity of the inflow port in the liquid tank for detecting the temperature of the ultrasonic medium flowing from the inflow port into the liquid tank, and a temperature and an ultrasonic propagation velocity of the ultrasonic medium. According to the temperature detected by the temperature sensor at the time when this setting is made, the table showing the correspondence relationship between the table and other corresponding means, and the time set as the delay time for the enlarged display of the ultrasonic echo are set as the first time. The ultrasonic wave propagation speed obtained by the table or other corresponding means is defined as the first speed, and is obtained by the table or other corresponding means in accordance with the temperature detected by the temperature sensor at the time of measuring the ultrasonic echo of the display target. Computing means for correcting the first time in accordance with the ratio of the first speed and the second speed when the sound wave propagation speed is the second speed, and calculating the result as the second time. An ultrasonic inspection apparatus, comprising: and displaying the waveform of the ultrasonic echo in an enlarged manner in accordance with a timing delayed by the second time from a predetermined reference timing.