JPS5963508A - Apparatus for measuring descaling state of steel plate - Google Patents

Abstract

PURPOSE:To measure a descaling state of a steel plate surface at each position for the width direction of the steel plate by the photodetected intensity by irradiating light to the steel plate surface at each position for the width direction and photodetecting the reflected light at each position for the width direction of the steel plate. CONSTITUTION:The light generated from light sources 7, 8 are reflected at the surface of the steel plate 1, the diffused and reflected light is made incident to an optical sensor 15 of each channel of an optical sensor part 9, the light is photodetected by photodiode and the current corresponding to the light intensity is outputted. The output is converted to a voltage signal by an I/V converter 22, the noise is eliminated by a low-pass filter 23, then is inputted to a sample holding circuit 25 through an amplifier 24. In case of driving light sources 12, 13 by AC voltage, the photodetected signal Vd is sampled for every peak of AC voltage waveforms. A comparator 27 compares the sample hold value Vd of the circuit 25 with the reference level Vr set by a level setting device 28, and outputs a signal S indicating the bad descaling state in case of Vd<Vr.

Description

[Detailed Description of the Invention] This invention provides a device for measuring the state of descaling treatment of a steel plate.
It is related to VC.

In processing a steel plate, descaling treatment is performed to remove scale formed on the surface of the steel plate. Descaling treatment can be carried out, for example, by injecting an abrasive onto the surface of the steel plate, but if the injection pressure is improperly adjusted, the scale will not be removed sufficiently, resulting in poor descaling and problems with subsequent processing. One thing that caused a problem. Therefore, in the descaling process, it is necessary to measure the shape of the surface of the steel plate after the process.

In the past, the descaling state was measured visually16, and this method had some drawbacks.

1) To perform measurements, the descaling device must be stopped. Therefore, it is not possible to measure the descaling state during line operation, resulting in poor efficiency.

+1) Visually measuring the descaling state of the entire M plate is time consuming and inaccurate, and variations occur depending on individual measurements. Therefore, this measurement cannot accurately determine the performance of each injection nozzle of the descaling device based on the results.

This invention was made in view of the above-mentioned point VC, and aims to provide a steel plate descaling measuring device that can accurately measure the surface condition of a steel plate after descaling treatment in real time. .

According to this invention, a light beam is directed toward the surface of a steel plate and irradiates each position in the II direction, and the reflected light is received at each position in the width direction of the steel plate, and the intensity of the received light is determined by the 111
11';i! , the scale condition is measured at each position in the 1 quotient direction of the steel plate. That is,
If the descaling is sufficiently r and z, the reflectance of the umbrella plate surface will be even lower and the light reception Ii! If the descaling is defective, the reflectance of the steel plate surface (2) will be low and the received light intensity will be weak (rx), so this is used for measurement.

Hereinafter, embodiments of the present invention will be explained with reference to the drawings.

Figure 1 shows an example of the arrangement of the light sources and optical sensors used in this masterpiece. In Figure 1, a heated steel plate 1 is fed into a descaling device 2 . The descaling device 2 is of a wet type blast type here, and descaling is performed by applying abrasive material or the like from a nozzle 3 to the surface of the steel plate 1 [1+㎜].

In this case, a linear light source 7.8 is directed toward the surface of the steel plate 10,
They are arranged one space apart from the steel plate 1. The light sources 7.8 are constructed by covering the inner curves of fluorescent lamps 10 and 11 with black-treated anti-scattering guides 12 and 13, respectively. An optical sensor section 9 is arranged in a straight line on one side of the light source 7.8 of the housing. The optical sensor section 9 includes a cylindrical scattering prevention guide 14 (diameter 30φ to 5mm) whose inner surface is blackened.
(about 0φ) in which lenses are arranged in negative rows. The anti-scattering guide 14 is an optical sensor 15
1C functions to suppress the intrusion of light other than the diffusely reflected light immediately below it. If each optical converter 15 is provided in a one-to-one ratio with each nozzle 3 of the descaling device 2, it is possible to easily determine which of the nozzles 3 is malfunctioning in the event of descaling failure. Incidentally, the reason why two light sources are provided in the practical example shown in FIG. 1 is to increase the amount of diffusely reflected light incident on the optical sensor section 9 by increasing the amount of irradiation onto the steel plate 1. In addition, in the case of a single lamp, variations in the amount of acid incident on the optical sensor section 9 increase due to the unevenness of the steel plate 1, but this variation can be prevented by irradiating from two directions.

Figure 2 shows the state in which the light sources 7, 8 and optical sensor section 9 in Figure 1 are cut perpendicular to the curve of the steel plate 1 and parallel to its conveying direction. In FIG. 2, the light sources 7.8 are arranged symmetrically with respect to the optical sensor section 9, and the fluorescent lamp 1.
0 and '11 are irradiated onto the surface of the steel plate 1 directly below the optical sensor section 9. Optical sensor section 9
The interior surrounded by the scattering light prevention guide 14 includes a lens, a photodiode 21 into which the light focused by the lens enters, and an X/V converter that converts the output current of the photodiode 21 into a voltage signal. It is arranged perpendicularly to the surface of the steel plate 1, and is arranged so that the diffusely reflected light from the steel plate 1 is received by the photodiode 2 through the lens 9. Note that the photodiode 2j is one that is sensitive to a wide range of original wavelengths (for example, one that responds from the outer wavelength range to the near-infrared range). This means that the wider the sensitivity range, the higher the current generated by light will be.
This is because the ratio improves. The diffusely reflected light received by the photodiode 2 is at the height rJL of the light beam on the steel plate 1.
It is strong when the descaling state (that is, the position directly below the optical sensor part 9) is good, and it becomes weak when the descaling is not sufficient.
The output voltage of the transformer ρ is the descaling rate (represents the degree of descaling processing state, and the descaling is complete vC11
An example is shown in FIG. 3, where 1ooi is the state in which the event has been performed, and 0 is the state in which the event has not been performed at all. The characteristics shown in Figure 3 are the amount of irradiated light and the angle of incidence (the angle of incidence is the light source 7
．． By changing the slope of 8, the f angle of the curve changes, for example, in the range of 40 to 60 degrees.

FIG. 4 shows a small example of an apparatus for measuring the descaling state using the above configuration.

Here, a reference level Vr for descaling failure is set in advance, and the level Vd of the light reception signal is set to this -jk.
, when the quasi-level becomes lower than r, the descaling failure detection signal No. 1g S is generated.

Although FIG. 4 shows a processing system for the optical sensor 15 of one channel in the optical sensor unit 9, in reality, the same system is provided for each channel.

In FIG. 4, the light source 7.8 is illuminated by a power source from a fixed power source. The light from the light source 7.8 is the steel plate 10
The diffusely reflected light is reflected by the surface and enters the optical sensor 15 of each channel in the optical sensor section 9vc. Optical sensor 1
The light incident on the photodiode 21 is received by the photodiode 2 (FIG. 2), and the photodiode 21 outputs a direct current according to the intensity of the light.

The output 'DC' of the photodiode 2J is converted into a direct voltage signal by an I/V controller 22, and after noise is removed by a low-pass filter, it is input to the sample-and-hold circuit 5 via an amplifier.

By the way, when the light sources 12 and 13 are driven by the father current dragon pressure, the illuminance of the light sources 12 and 13 does not change all at once, but constantly flickers in synchronization with the father current voltage waveform. Therefore, light reception 1
Accurate detection cannot be performed by continuously comparing No. 6 vd with the reference level Vr. Therefore, in this implementation v11VC, in order to check the received light intensity under constant headlight,
The light receiving signal Vd is sampled at each peak of the current voltage waveform.

The peak detection circuit 26 detects each peak of the AC voltage waveform between the power sources of the light sources 13 and 12, and samples and holds the received light 1f19Vd at that timing.

Since the σλ peak of the AC voltage waveform occurs every half cycle, if the voltage between the power supplies is
Hz), the sampling period is 5
The case is 0 Hz, and the case is 6 (lHz).111@ From the relationship with the moving speed of the plate 1, sufficient measurement can be performed even with a sampling period of this order.

The ratio device 27 compares the sample and hold circuit B's sample and hold li [Vd with the 4 quasi-level Vr set by the level setting circuit, and when Vd (Vr), it indicates that the descaling process is defective. Outputs a signal S. This No. 100 S can, for example, generate an alarm for defective descaling, and at the same time adjust the injection pressure A phasing of the injection nozzle 3 at the corresponding position in the descaling device 2. Or it can be used for cutting and dusting.

FIG. 5 shows an example of the apparatus shown in FIG. 4 described above. Since the light sources 7 and 8 are driven by alternating current (AC), the old source number Vd fluctuates at the period of half a cycle of the father current power source: illusion. By sampling this received light signal Vd at each positive and negative peak of the father current source voltage,
The sample-and-hold circuit 25 holds a level corresponding to the received photovoltaic signal #. If there is a defective descaling point, the location thereof should be noted.In the above embodiment, two light sources 7.8 are provided to sandwich the tapered sensor section 9, but the number of light sources may be one.

As explained above, according to the present invention, the descaling process can be accurately measured in real time by utilizing the fact that the reflectance of the top plate surface changes due to the descaling process. Therefore, work efficiency is improved9. Moreover, unlike the conventional visual inspection method, there is no variation in measurement values, and the stability of the measurement bag is improved.

Since we performed independent Vci'+ measurements on each of the 11 parts of the steel plate in the housing and obtained a value of 9, it was easy to determine which part in the width direction of the middle plate was defective in descaling [f-IJ cutting, nozzle It is easy to adjust the injection pressure, exchange, etc. with VC, and it is also an OT function to do this with a cut.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the light source 7.8 used in the present invention, cut along a plane perpendicular to the light plane and parallel to its conveying direction;
FIG. 243 is a graph showing the relationship between the descaling rate and the output voltage of the I/￥f converter 22 in FIG. FIG. 5 is a block diagram showing an example of a device that performs state measurement.
The figure is a waveform diagram showing an example of the operation of the apparatus of FIG. 4. 1... Steel plate, 24... Descaling device road, 3...
Abrasive injection nozzle, 7.8... Light source, 9... Optical sensor unit, 10°1]... Fluorescent pair, 12, 13, 1
4...Scatter prevention guide, 15 Figure 2 Figure 5 Opening Figure 3

Claims (1)

[Claims] a light source that irradiates light beams at each position in 11 directions on the surface of the steel plate;
Each optical sensor receives the reflected light from the same position across the width of the steel plate surface by the light source, and the descaling state at each position in the width direction of the steel plate surface is measured based on the output of each of the optical sensors. A measuring device for descaling steel plates with means.