High-temperature slab imaging temperature detecting system in secondary cooling zone of continuous casting machine and temperature detecting method thereof

Abstract

The invention belongs to the technical field of steelmaking and continuous casting, in particular to a high-temperature slab imaging temperature detecting system in a secondary cooling zone of a continuous casting machine and a temperature detecting method thereof. The system comprises a micro-color CCD camera, a video image acquisition module and an industry computer, wherein the micro-color CCD camera is arranged above the inner arc of the secondary cooling zone of the continuous casting machine and is used for acquiring the two-dimensional image information of a slab; the video image acquisition module is used for receiving and saving the two-dimensional image information; and the industry computer is used for processing and analyzing the two-dimensional image information and displaying a final result. Based on the color video imaging and computer image processing technologies, the method converts the chroma information of pixels in a high-temperature slab color image which is subjected to image preprocessing into temperature information, performs modifying processing on the temperature of the pixel the surface of which is coated by scale, and finally outputs the maximum value and the average value of the temperature. The temperature detecting method has the advantages of simple and convenient operation, high accuracy, quick dynamic response and wide application range, can be easily integrated to dynamic soft press, electromagnetic stirring and dynamic water distribution of secondary cooling, and has wide industry application prospect.

Description

technical field [0001] The invention belongs to the technical field of steelmaking and continuous casting, and in particular relates to an online continuous detection system and method for the surface temperature of a high-temperature billet in a secondary cooling zone of a continuous casting machine. Background technique [0002] There are two methods of measuring temperature: contact method and non-contact method. In the contact temperature measurement method, thermocouples and thermal resistance thermometers are the most commonly used. The advantage of this method is that the equipment and operation are simple, and the real temperature of the object is measured. The disadvantage is that the dynamic characteristics are poor, and due to the need to contact the object to be measured , so it has an influence on the temperature distribution of the measured object. At present, the non-contact temperature measurement method is mainly based on radiation temperature measurement m...

AI Technical Summary

Problems solved by technology

It has many deficiencies, and its application is of little significance: (1) First, it is still impossible to rule out the influence of the iron oxide scale on the surface of the slab on the temperature measurement

(2) The thermometer rotates synchronously with the back-up roll of the casting machine, so the temperature detection cycle will be affected by the fluctuation of the casting machine's pulling speed, sometimes fast and sometimes slow

When the casting speed is low, the time interval between two adjacent thermocouples contacting the slab increases, which means that the detection cycle becomes longer

(3) A thermometer can only measure the temperature of one point, but multiple thermocouples are used. If the number is too small, the detection cycle will become longer, resulting in untimely temperature measurement; if the number is too large, the number of thermocouples will be increased. The installation difficulty and maintenance cost, especially when one or some thermocouples are not installed properly or the readings jump, may bring more system errors

Its disadvantages are (1) it is only limited to the temperature measurement of the slab located in the straightening area, and does not involve the more complicated secondary cooling spray area

Even in the straightening area, the direct use of infrared temperature measuring probes still cannot accurately measure the surface temperature of the slab

(2) The analysis system only has simple analysis functions, and does not yet have the ability to analyze and feed back equipment conditions and slab quality in combination with the continuous casting process

The disadvantage of this patent is that (1) it fails to fully consider the influence of the high-temperature and high-humidity water mist medium around the slab and the iron oxide scale on the surface of the slab on the temperature measurement, (2) the approximate maximum value of the temperature is obtained by increasing the detection cycle , the purpose of real-time detection of surface temperature cannot be achieved. (3) It is difficult to detect the accurate temperature of each typical control point in the secondary cooling zone by using this method

Invention patent CN200510110014.X "A Continuous Casting Slab Surface Target Temperature Monitoring Method and Its Device" discloses a continuous casting slab surface target temperature monitoring and analysis method, which can effectively analyze the feedback results of existing monitoring devices and make the It is connected with the continuous casting process and equipment status, but limited to its temperature detection, it still uses an infrared thermometer, which has the same problems as the above-mentioned patents

[0008] It is often difficult to obtain reliable monitoring data by using common detection methods, or the real temperature cannot be measured, or the temperature measurement element is damaged prematurely and the measurement is interrupted.

Invention patent application number 200780019591.5 "Continuous casting slab surface temperature measurement method and device" discloses a continuous casting slab surface temperature measurement device and method, using a high-resolution thermal imager and scanning infrared thermometer, combined with model filtering , basically meet the requirements of billet temperature measurement, but its equipment cost is extremely high, maintenance is difficult, and it is rarely used on continuous casting machines

However, if there is no preprocessing of the slab image and filtering of the result data, it is still difficult to obtain the real temperature of the slab due to the influence of surface water mist and iron oxide scale, and it is not combined with the process parameters, which has little guiding significance for the production process

[0009] Invention Patent Application No. 200910077462.2 "A Color CCD-Based Radiation Temperature Field Measurement Device and Method" discloses a color CCD-based temperature field measurement device, which is different from this patent in that there are differences in the realization of the temperature calculation principle, and The former requires the switching of optical filters, and its mechanical and optical systems are relatively complicated, and it has not considered the special circumstances such as the continuous casting slab being covered by iron oxide scale

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