JPS6063406A - Radiation thickness gauge - Google Patents

Abstract

PURPOSE:To discriminate accurately variance of the thickness of the tip part of a material to be measured by outputting raw data at intervals of a reference counting time from the start of measurement to an average operation time and outputting the average operation result of moving average thereafter. CONSTITUTION:Radiant rays 3 radiated from a ray source 2 are made incident to a detector 5. In this case, if a steel plate 4 runs between a vessel 1 and the detector 5, a part of radiant rays 3 is absorbed by the steel plate 4, and attenuated radiant rays (transmitted rays) are made incident to the detector 5. The output of the detector 5 is amplified by an amplifier 6 and is converted to a pulse signal by a V-F converter 7 and become input data of an integrator 8. When the steel plate 4 running in the arrow direction is detected by a steel plate detector 13, an operation processing device 10 is switched automatically to measurement. In the integrator 8, input data is sampled at intervals of the reference counting time by a trigger from a reference time generator 9 and is integrated. This output is inputted to the operation processing device 10 and is used for average operation of moving average together with a set value of a moving average time setter 14.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] Does the present invention apply to high temperatures? This relates to radiation thickness 1, which uses radiation to measure the thickness of a steel plate or the like that is running at high speed.

[Technical background of the invention and its problems]

A radiation thickness meter uses a radiation detector to detect the radiation emitted from a radiation source and transmitted through the material to be measured, and calculates the thickness of the material to be measured from the ratio of the incident radiation to the transmitted radiation. Because it can measure the thickness of the material to be measured without touching it, it is used to measure the thickness of steel plates that run at high temperatures and high speeds in rolling equipment.

In that case, average calculation is performed to determine the plate thickness, but conventionally, as shown in Figure 1, from the start of measurement until the average calculation time T'4 is reached, every set standard counting time a is used, The data of Tl # T2 e I'3rT4 is cumulatively averaged, and after reaching the average calculation time ri, the average calculation is performed using a moving average for each reference counting time a.

However, in such a method, the thickness of the tip of the steel plate is calculated based on a cumulative average, so there is a drawback that the amount of change in the plate thickness cannot be determined.

[Purpose of the invention]

An object of the present invention is to provide a radiation thickness meter that can accurately determine the amount of change in thickness at the tip of a material to be measured.

[Summary of the invention]

The present invention includes a radiation source container that houses a radiation source, a detector that detects radiation emitted from the radiation source, and a converter that converts the output of this detector into a pulse signal with a frequency corresponding to the analog amount of the radiation source.
-r converter, a reference time generator that generates a reference time signal, and using the output signal of this reference time generator as a trigger signal, the output of the V-F converter is sampled and integrated every reference counting time. an integrator, a measured material detector that detects a measured material traveling between the radiation source container and the detector, a processing device that calculates the thickness of the measured material from the output of the integrator, and a moving It is equipped with a moving average time setting device that sets the average time, and outputs data (raw data) for each reference counting time from the processing unit from the start of measurement until reaching the average calculation time, and thereafter outputs data (raw data) for each reference counting time. This radiation thickness meter is characterized in that it outputs a value calculated using a moving average.

[Embodiments of the invention]

FIG. 2 shows an embodiment of the present invention, in which 1 is a radiation source container, 2 is a radiation source housed in this container 1, and emits radiation 3. 4 is a steel plate as a material to be measured, 5 is a radiation detector, and the steel plate 4 runs between this detector 5 and the radiation source container 1.

6 is an amplifier for amplifying the output of the detector 5; 7 is a V-F converter for converting the output of the amplifier 6 into a pulse signal having a frequency corresponding to its voltage value; 8 is an integrator; 9 is an integrator; The integrator 8 uses the output of the reference time generator 9 as a vir signal and integrates the output of the V-F converter 7 by using a reference time generator.

10 is an arithmetic processing unit, 11 is a display/recording device, 12 is a process computer, 13 is a steel plate detector for detecting the steel plate 4, and 14 is a moving average time setting device. The arithmetic processing unit 10 receives the detection signal from the copper plate detector 13 and switches to measurement), and calculates the copper plate based on the output of the integrator 8 (data for each reference counting time) and the setting value of the moving average time setting device 14. 4 and outputs the result (deviation, absolute value) to the display/recording device 11 and process computer 12 f7:.

In this case, as shown in Figure 3, raw data for each standard counting time a is output from the start of measurement until reaching the average calculation time TI4, and then average calculation is performed using a moving average for each standard counting time a. I am trying to output the results.

Next, the operation will be described. Radiation 3 emitted from the source 2 enters the detector 5 . In this case, when the steel plate 4 runs between the container 1 and the detector 5, a portion of the radiation 3 is absorbed by the steel plate 4, and the reduced radiation (transmitted radiation) enters the detector 5. The output of this detector 5 is amplified by an amplifier 6 and then converted into a pulse signal by a V-F converter 1, which becomes input data to an integrator 8. Further, when the steel plate 4 traveling in the direction A shown in the figure is detected by the steel plate detector 13, the processing unit 10 automatically starts measuring 9J! D change.

The integrator 8 digitizes and integrates the input data every reference counting time based on a trigger from the reference time generator 9. This output is input to the arithmetic processing unit 10, and used together with the set value of the moving average time setter 14 for average calculation in the moving average.

This arithmetic processing device 10 outputs the measured value for each reference counting time, regardless of the setting value of the moving average time setter 14, until the moving average time is reached, and thereafter average calculation is performed using the moving average. The result will be output.

For example, as shown in FIG. 4(,), the thickness of the tip of the steel plate 4 is T, 2T, 3T, 4T, and 3T.

When the thickness changes sequentially from 2T to T, as shown in FIG. 4(,), the measured values for each reference counting time a are output as T, 2T, and 3T, and the plate thickness changes are faithfully reflected in the measured values.

Incidentally, with the conventional cumulative average, the measured values are T, 1.5T, 2T, and 3T as shown in FIG. 4(b), and the amount of change cannot be accurately determined.

In the illustrated example, the reference counting time is fixed at a,
It can be changed as appropriate. Similarly, the set value of the moving average time is also arbitrary.

〔Effect of the invention〕

As described above, according to the present invention, raw data is output for each reference counting time from the start of measurement until reaching the average calculation time,
After that, we started outputting the average calculation result of the moving average, so it was possible to accurately determine changes in the plate thickness at the tip of the material to be measured, and the accuracy of AGC (automatic plate thickness control) of rolling equipment. This method has the advantage that it is possible to accurately judge whether the information is correct or incorrect.

[Brief explanation of drawings]

Fig. 1 is a diagram for explaining a conventional example of a calculation method when measuring the plate thickness of a traveling copper plate using a radiation thickness meter, and Fig. 2 is an example of an embodiment of the radiation thickness meter according to the present invention. 3121 is an explanatory diagram showing a calculation example of the same embodiment,
The fourth tA (a)-(b) p(,) is an explanatory diagram of the operation of the same embodiment. 1...8 radiation sources, 2...ray source, 4...copper plate (material to be measured), 5...radiation detector, 7...V-F converter, 8...integrator instrument, 9... reference time generator, 10...
・Arithmetic processing unit, 11...Display/recording device, 12...
・Norocess computer, 13...Copper plate detector, 14
...Moving average time setting device.

Claims (1)

[Claims] A radiation source container containing a radiation source, a radiation detector that detects radiation emitted from the radiation source, and a material detector that detects a material to be measured traveling between the container and the detector. , a V-F converter that converts the output of the radiation detector into a Noculus signal with a frequency corresponding to the value thereof, and a reference time generator;
The output of this reference time generator is used as a signal by the above V-
an integrator that samples and integrates the output of the F converter;
Receiving the detection signals of the moving average time setting device and the material to be measured detector as a measurement start signal, calculating the plate thickness of the material to be measured based on the output of the integrator and the setting value of the moving average time setting device; The radiation thickness is equipped with a calculation processing device that outputs raw data for each standard counting time from the start of measurement until reaching the average calculation time, and then outputs the results of averaging calculations using the moving average for each standard counting time. Total.