JPH01147310A - State measuring instrument for coating member - Google Patents

Abstract

PURPOSE:To obtain the instrument which takes a measurement without being affected by noises while removing the noises by detecting an abnormal part of time characteristics of a secondary reflected wave, and correcting it with time characteristic of a primary reflected wave and obtaining thickness information on a coating member. CONSTITUTION:The instrument which measures the state of the coating member 2 having a thin film layer 3 on the surface with the ultrasonic wave detects the time of the primary reflected wave 3' from the bottom surface of the coating member based upon a reflected wave 1' from the coating layer and the time of the secondary reflected wave 4' based on the reflected wave 1' or 3'. The part A where the characteristics of time data Qt2 on the secondary reflected wave 4' are abnormal is detected. Then measurement data on this abnormal part A is corrected with characteristics of a part B of time data Pt1 on the primary reflected wave 3' corresponding to the A, and thickness information on the coating member 2 is obtained according to the corrected secondary reflected wave data.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] This invention relates to a device for measuring the condition of a coating member, and more specifically, it measures the corrosion condition of the back surface of a plate material with a coating film, such as a bottom plate of a raw/heavy oil tank, This invention relates to a corrosion metal status measuring device for displaying information.

[Prior Art] Generally, when measuring the plate thickness of a member with a coating film using ultrasonic waves, it is done by measuring the time interval between the primary reflected wave and the secondary reflected wave from the bottom surface. By measuring the primary reflected wave and secondary reflected wave, the time of the ultrasonic wave passing through the coating is canceled, and only the thickness of the plate is 4.
111 can be determined.

[Problems to be solved] However, as shown in Figure 4 (a) and (b), when measuring the thickness of the corroded remaining wall of a tank bottom plate with a coating film,
When the bottom surface has severe irregularities and the scattering of sound waves on the bottom surface is large, sufficient ultrasonic reflected waves will not be reflected as secondary reflected waves.

In FIG. 4(a), 8 is an ultrasonic probe, and 1
is the ground, 2 is the bottom plate of a crude oil tank placed on L of the ground 1, and 3 is a resin layer coated on the surface of the bottom plate 2. And ■.

■ indicates a reflected wave from the surface or bottom of the coating resin layer 3, ■ indicates a primary reflected wave from the bottom of the bottom plate 2, and ■
is the secondary reflected wave.

In this case, the waveform of the echo signal received by the ultrasonic probe 8 is as shown in FIG.

The wave indicated by ``■'' is a received echo signal obtained corresponding to the reflected waves of ``2'' and ``2'' described above, and the waveform indicated by ``■'' which follows it is a received echo signal corresponding to the reflected wave ②. The waveform ``■'' is the received echo signal corresponding to the reflected wave ``■''. The waveform marked "■" after that is the part on which noise etc. are added.

In addition, the time tl represents a path corresponding to the thickness of the resin layer + bottom plate, and is the time interval from the reflected wave from the surface or bottom of the coating resin layer 3 to the primary reflected wave from the bottom of the success/failure 2. , time t2 represents a path corresponding to the thickness of the bottom plate, and is the time interval from the primary reflected wave to the secondary reflected wave from the bottom surface of the bottom plate 2.

Here, the secondary reflected wave shown by the reflected echo signal The value will be inaccurate. Therefore, when counting and measuring at multiple points by scanning the back surface and processing the results and displaying them, many pixels showing abnormal values, that is, noise, appear in image 1-, making the image difficult to see. Put it away. especially,
In order to detect the secondary reflected wave from the bottom surface, a highly attenuated sound wave is detected, which is close to the noise level.
The detection tends to pick up noise.

The present invention solves the problems of the prior art, and aims to provide a coating member condition measuring device that can obtain measurement data free of noise.

[Means for Solving the Problems] Means in the apparatus for measuring the condition of a coating member of the present invention to achieve such an object is to measure the state of the coating member from the bottom surface of the coating member using the reflected wave from the coating layer of the coating member as a reference. The time of the primary reflected wave and the time of the secondary reflected wave from the bottom of the coating member based on the reflected wave from the coating layer or the primary reflected wave are respectively measured, and the time is based on the measured time of the secondary reflected wave. The characteristics of the abnormal part are detected from the characteristics, the characteristics of this abnormal part are corrected to the characteristics of the changing state corresponding to the changing state of the time characteristics based on the time of the measured primary reflected wave, and the characteristics of the corrected secondary reflected wave are The thickness information of the coating member itself is obtained based on the time characteristics.

[Operation] In this way, by correcting the abnormal part of the time characteristic of the secondary reflected wave with the time characteristic of the primary reflected wave, the noise part is reduced to tJl.
It is possible to obtain time characteristic data of the removed secondary reflected waves, and thereby thickness data that is not affected by noise can be obtained.

Therefore, the image processed and displayed regarding the thickness becomes easy to see.

[Embodiment] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a graph of measurement data in an ultrasonic measuring device for the corrosion state of the bottom plate of a raw/heavy oil tank to which the coating member condition measuring device of the present invention is applied, and FIG. 2 is a block diagram of the ultrasonic corrosion state measuring device. 3A and 3B are flowcharts of processing centered on IE processing for correcting the temporal characteristics of secondary reflected waves in the three-dimensional image processing apparatus.

In FIG. 1, P t t is the super? It shows the time characteristic of the primary reflected wave of a certain scanning line in °1 wave measurement, and Q t 2 is similarly the time 4!11 constant data L2 of the secondary reflected wave ■ in (b) of Fig. 4. 3 shows the time characteristics of the secondary reflected waves of the scanning line obtained in accordance with FIG. Therefore, the vertical axis of this graph is the plate thickness, and the horizontal axis is the measurement position from the origin of the scanning device.

In the figure, the part indicated by A of the time characteristic Qt2 of the secondary reflected wave is a part (noise point) of abnormal characteristics caused by the influence of noise. Moreover, T is the difference between the time characteristic Pt/ of the -wide reflected wave and the time characteristic Qt2 of the secondary reflected wave,
This corresponds to the thickness of the coating resin layer 3 in FIG. 4(a).

Here, the change in the thickness of the coating resin layer 3 is a gradual change unless there is special reason because it is applied. Therefore, the abnormal part A affected by noise is usually , corresponding to the thickness T of the coating resin layer 3, changes along the time characteristic pt7 of the broad reflected wave.Therefore, an abnormal characteristic portion A of the time characteristic Qt2 of the secondary reflected wave occurs. Detect measurement points M and N before and after the measurement, and calculate the time characteristic of the primary reflected wave between these positions M and N.
The time characteristic B between M and N is corrected so that the characteristic during this period becomes the time characteristic Qt shown by the dashed line.

As a result, the time characteristic Qt2 of the secondary reflected wave including the dashed-dotted line from which noise components have been removed can be obtained, and thickness data with almost no noise can be obtained.

Now, time data t1. of such primary reflected waves with respect to the bottom plate of the Hara Ichiura tank. Time data t2 of secondary reflected wave
The second figure shows a block diagram of the ultrasonic flaw detection device that collects
In FIG. 2, 20 is an ultrasonic measuring device, and 21 is a three-dimensional image processing device for the measurement data, which is disposed outside the crude oil tank 11. Reference numeral 22 denotes the measurement data collection device ξ, which is carried into the raw and heavy oil tank 11, and is connected to the phases 11-. 4 are connected. In addition, 1
2 is a manhole provided in the raw heavy oil tank 11.

The transmission pulse signal outputted from the ultrasonic flaw detection device 5 is applied to the ultrasonic probe r8, and the bottom plate 1 of the raw and heavy oil tank 11 is
The reflected echo from 1a (see Figure 1) (the primary reflected wave and secondary reflected wave as its surface echo and bottom echo) is
The received ultrasonic probe r-8 sends the received echo signal to the ultrasonic flaw detection device 5.

The ultrasonic flaw detector 5 amplifies this received echo signal using a pulser/receiver 51 and applies a gate to detect a peak. Then, a pulse signal corresponding to the peak detection corresponding to the surface echo is generated as a counting start pulse signal, and a pulse signal corresponding to the peak detection corresponding to the bottom echo (-wide reflected wave and secondary reflected wave, respectively) is stopped counting. Each signal is generated and sent to the counting circuit 52. The counting circuit 52 counts the clock signal for each of the primary reflected wave and the secondary reflected wave from receiving the counting start pulse signal until receiving the counting stop L pulse signal, and sends these respective values to the control device 7. Send.

The control device 7 receives the count value from the counting circuit 52 as a plate thickness count value in the control section 71, sends a control signal from the control section 71 to the drive device 72, and operates the +i-plane scanning mechanism 4.
(for example, by moving one pitch) to move the super j゛1-wave probe 8 to the next measurement position, and perform a similar 4!11
Obtain constant data.

The control device 7 converts the time interval data from the primary reflected wave to the secondary reflected wave from the obtained measurement data into 11. of the secondary reflected wave. ')
i lil /Il! The time measurement data 17 of the cholera primary reflected wave, the time measurement data t2 of the secondary reflected wave, and the position data of the ultrasound probe 8 (for example, the coordinate position in the XY scan of the plane scanning mechanism 4) data) are sequentially sent to the image processing device 6I of the monitor device 6. The image processing device 81 converts the measurement data value into luminance according to the value, and converts the position data of the ultrasonic probe r8 into a Y-direction deflection signal and an X-direction deflection signal according to the value. The measured data sent sequentially from the control device 7 is sequentially converted and controlled to be displayed as an image.

The control device 7 also controls the time measurement data t7. of the primary reflected wave and the primary reflected wave. t2 and super i'ri him probe J'8
The position data are sequentially sent to the optical transmission circuit 73 and transmitted to the optical reception circuit 14 of the measurement data three-dimensional image processing device 21 via the optical fiber 3.

These measurement data t/, t2 and the ultrasonic probe 8 are used as data regarding the thickness of the bottom plate received by the optical receiving circuit 14.
The position data is the measured data three-dimensional image processing device 210
The data is processed by an arithmetic processing unit 13 equipped with a microprocessor and stored in an external storage device 15. At the same time, all the past measurement data stored in the external storage device 15 is read out from the external storage device 15 and processed, and according to the instruction information inputted from the keyboard 16, the cross-sectional state, island root, contour line display, etc. Is the three-dimensional display etc. on the CRT display 17? I get hit.

Here, the three-dimensional image processing device 21 includes an external storage device 15
The time measurement data of the primary reflected wave and secondary reflected wave stored in t1. t2 and position data of the ultrasonic probe r-1 are obtained. Figure 1 shows this in graph form.

These time measurement data 1/, 12 are then subjected to the processing shown in Fig. 3, which detects an abnormal part of the time characteristics of the secondary reflected wave and converts this abnormal part into a change in the time characteristics of the primary reflected wave. Move the hat as it is and make supplementary 11 mo. Next, this catch i1
Thickness information is obtained based on the time product +vt2 of the secondary reflected wave of the abnormal characteristic portion that is E and the time information t2 of the secondary reflection of the uncorrected portion that is not normal.

To explain the details of such processing, in processing step 100 in FIG. 3, variables i and j are set to i=1. j = 1, and in the next step 101, from the time measurement data 1/, 12, the difference value St = j71 - t2i (where 1 = l - n, n
calculates the total number of 71111 fixed points in a certain area). This difference value S1 is stored, and in the next step 102, it is determined whether the absolute value of the difference with the previously calculated difference value S i-7 is less than the set value P, that is, P< +
3l-8l-/l? ■: Yes. l S(-8it
When l exceeds this set value P, it is determined that it is an abnormal characteristic part, and in step 103, the information of the 4111 fixed point of the measurement position i-1 one L before the measurement position i at this time is set as a variable. Set it to XJ. This corresponds to the measurement point M located at the front side of the normal characteristic portion A shown in FIG. Note that in the determination at step 102, when i=1, which is the first determination, there is no previous data, so this determination is not performed.

Then, in step 104, j is updated as j=j+1, and in step 105, it is determined whether or not the process has finished. If there is still time measurement data, i is updated in step 106. is updated as i=i+1, and as long as there is next measurement data regarding the abnormal characteristic, information on the measurement point is sequentially stored while updating the variable Xj. Also,
As a result of the determination in step 102 above, ! St-5l
If -t l does not exceed the set value P, the process moves to step 105 since it is not an abnormal characteristic.

In such processing, when the characteristics return to normal from the abnormal characteristic measurement state, steps 102 to 1 are performed.
05, returns from step 106 to step 101, and repeats the same process from step 101. Then, if there is an abnormal characteristic part, then the abnormal/! l11 Fixed point data is set to variable Xj at that measurement point.
It is memorized from the moment before, and it is repeated. Therefore, the 71!11 fixed points of each abnormality characteristic location are sequentially recorded from the data one before the point to the point one L before the last abnormality measurement point.

If we obtain a variable Xj indicating each measurement point of each abnormal characteristic from before L entering the abnormal characteristic point (a part where measurement points are continuous) obtained in this way, the first measurement of each abnormal characteristic point among these The point corresponds to the position of the measurement point Mk (k is from 1 to the total number of abnormal characteristic locations) in FIG. 1 before the start of correction for abnormal characteristics, and the /I! of continuous abnormal characteristics. 11 Two measurement points from the last point of the fixed points This corresponds to the end point Nk of .

Therefore, in the next step 107, the next reflection at the position corresponding to the first measurement point (measurement point Mk before the start of correction) among the variables X of consecutive measurement points corresponding to each abnormal characteristic location Time measurement data of wave and secondary reflected wave L/+t2
, take these differences from the '1 sex, and set the value Tk corresponding to the film thickness at that position to the 1fl11 fixed point M before each correction starts.
Calculate and store k.

In the next step 108, the measurement point M before each abnormality correction is started.
Compensation iF: by subtracting the value Tk corresponding to the film thickness from each measurement value of the time measurement data t7 of the primary reflected wave at the measurement points between k and the abnormal end point Nk.

Find the value. That is, for the time measurement data t2 of the secondary reflected waves for each measurement point from the measurement point Mk before the start of each correction to the abnormality correction end point Nk, a correction value t2c :i7-'rJ for this is calculated, This is replaced with time measurement data t2 and each /! of the abnormal characteristic part is replaced. i+1
It is stored as time measurement data of secondary reflected waves at fixed points.

After performing such correction for each ultimate characteristic 1, in step 109, the measurement time value t2 at each position of the non-abnormal part of the secondary reflected wave and the abnormal part of the secondary reflected wave obtained by the above correction are calculated. The time characteristic data consisting of the corrected measurement time value t2 is synthesized as thickness data and stored in the internal memory of the measurement data three-dimensional image processing device 21 or the external storage device 15.

The thickness data obtained from the data corrected in this manner is processed by the microprocessor of the arithmetic processing unit 13, and the image data of 6 presses is displayed on the i'1llll constant data tertiary data three-dimensional image processing unit 21 ray 17. That will happen.

By the way, the setting value P, which is the criterion for determining the above-mentioned abnormal characteristics, is
This is a constant value selected corresponding to the average change in the thickness of the coating thin film layer 3, which is the maximum change in the thickness +, )
Further, it may be a value determined experimentally from a comparison value obtained by experimentally obtaining an abnormal characteristic and a non-abnormal characteristic. In addition, changes due to corrosion under normal conditions
may be set as the maximum value or .II-average value.

Furthermore, in cases where it is desired to more completely cut out the noise part, the setting value P may be specially selected to a value lower than the average change in the thickness of the thin film layer t, 1, and this value The optimum value may be determined based on the relationship between noise and noise. Alternatively, the best screen may be displayed by allowing selection according to the state of the displayed screen.

As explained above, in this example, the entire thickness data is obtained after first correcting the time characteristic data regarding the secondary reflected waves. Of course, the thickness data may be obtained at the same time as the data correction. Also, when correcting the time data of the secondary reflected wave with the time data of the primary reflected wave, does it depend on the thickness of the coating layer at the measurement point before entering the abnormal characteristic?
+li iE, but this can be done by taking the thickness of several measurement points before this point and correcting it with the average value, or by
It may be corrected using a preset average film thickness or a function indicating thickness change.

In addition, in the example, the value of each abnormal measurement point is supplemented with the measurement data before entering the abnormal characteristic, but the measurement data before entering the abnormal characteristic and the following measurement data are sequentially compared. The abnormal data may be corrected each time the comparison is made.

In the embodiment, correction of the time data of wide reflected waves is performed in the measurement data three-dimensional measuring device, but such correction can be provided in the image processing device of the monitor device 6 disposed in the control device or the crude oil tank. You can.

In the example, the measurement data of the go-order reflection is the time interval data from the primary reflection to the secondary reflection. Of course, it is also possible to correct the constant part using the data of the primary reflected wave, and after correction, obtain the time interval data from the primary reflection to the secondary reflection as 11 constant data of the secondary reflection.

In addition, in the examples, the time interval between the primary reflection and the secondary reflection was measured based on the reflected wave from the surface or bottom surface of the coating layer, and the time interval for the secondary reflection wave was measured based on the reflection from the surface or bottom surface of the coating layer. Measured using waves as a reference −
・The difference between the time of the wide reflected wave and the time of the secondary reflected wave is calculated and obtained as the measurement time of the time interval of the secondary reflected wave. Of course, it is also possible to directly measure the time from the start to the secondary reflected wave using a time measurement circuit.

[Effects of the Invention] As can be understood from the following explanation, in this invention, the noise part is eliminated by supplementing the irregular part of the time characteristic of the secondary reflected wave with the time characteristic of the primary reflected wave. It is possible to obtain time characteristic data of the secondary reflected waves that have been reflected, and thereby thickness data that is not affected by noise can be obtained.

Therefore, the image processed and displayed regarding the thickness becomes easy to see.

[Brief explanation of the drawing]

FIG. 1 is a graph of measurement data obtained by an ultrasonic measuring device for the corrosion state of the bottom plate of a crude oil tank to which the coating member condition measuring device of the present invention is applied, and FIG. 2 is a graph of the measurement data of the ultrasonic measuring device for corrosion state. , Figure 3 is a flowchart of the process centered on the time characteristic correction process of the secondary reflected wave of the three-dimensional image processing device, and Figure 4 is an explanatory diagram of the measurement state of the bottom plate of the raw and heavy oil tank. be. 1... Ultrasonic probe r12... Bottom plate of raw and heavy oil tank,
3... Coating resin layer, 4... Plane scanning mechanism, 5
... Ultrasonic flaw detection device, 6... Monitor device, 7... Control device, 9... Optical cable, 11... Haraichi oil tank, 12... Manhole, 21... Three-dimensional measurement data Image processing device, 22.
...Measurement data collection device, 20...Ultrasonic measurement device.

Claims (4)

[Claims] (1) In a coating member condition measuring device that measures the condition of a coating member having a thin film layer on its surface using ultrasonic waves, the primary reflected wave from the bottom surface of the coating member is based on the reflected wave from the coating layer of the coating member. and the time of the secondary reflected wave from the bottom surface of the coating member based on the reflected wave from the coating layer or the primary reflected wave, respectively, and based on the measured time of the secondary reflected wave. The characteristic of the abnormal part is detected from the time characteristic, and the characteristic of this abnormal part is corrected to the characteristic of the changing state corresponding to the changing state of the time characteristic based on the time of the measured primary reflected wave, and the corrected secondary reflection is performed. An apparatus for measuring the condition of a coating member, characterized in that information on the thickness of the coating member itself is obtained based on the temporal characteristics of waves. (2) Detection of an abnormal part is based on the time interval between the time of the previously measured primary reflected wave and the time of the correspondingly measured secondary reflected wave, and the current similar time interval. 2. The coating member condition measuring device according to claim 1, wherein the difference value is larger than a set value. (3) The time measured for the secondary reflected wave is the time interval from the primary reflected wave to the secondary reflected wave, the coating member is the bottom plate of the crude oil tank, and the set value is the average thickness of the thin film layer. The apparatus for measuring the condition of a coating member according to claim 2, characterized in that the corrosion condition of the ground side of the bottom plate is measured in accordance with the amount of change. (4) The time measured for the secondary reflected wave is the time interval from the primary reflected wave to the secondary reflected wave. This is done because the difference value between the time interval measured for the reflected wave and the time measured for the secondary reflected wave and the current similar time interval exceeds the amount of change due to corrosion under normal conditions. 2. The coating member condition measuring device according to claim 1, wherein the coating member condition measuring device measures the corrosion condition of the ground side of the bottom plate.