The following benefits can be obtained from the infrared thermometer at each stage of the steel production process: high-quality products, improved productivity, reduced energy consumption, enhanced personnel safety, reduced downtime, easy data recording, infrared temperature measurement for steel processing and manufacturing. Main applications: continuous casting, hot blast stove, hot rolling, cold rolling, bar / wire rolling intelligent sensor head with digital circuit and two-way communication, remote parameter setting of the sensor head can be carried out in the control room, so that the function is enhanced and the control is more perfect. This is particularly important for metal materials with emissivity changes. To produce high-quality products and improve productivity, accurate temperature measurement is the key in the whole process of steelmaking.

When continuous casting turns molten steel into flat billet, slab or square billet, there may be production reduction or shutdown. Accurate real-time temperature monitoring, coupled with water nozzle and flow regulation, is required to provide appropriate cooling, so as to ensure the metallurgical properties required by the billet and finally obtain high-quality products. Improve productivity and prolong equipment life. The model of the selected sensor head is determined by the production process and the location of the sensor head. If it is installed in a harsh environment and its line of sight is blocked by dust, water mist or steam, the optical fiber dual color sensor head and integrated dual color sensor head are the best choices. If you need a temperature profile from edge to edge of the slab, you can use a line scanner. The type of hot rolling and the number and type of rolling mills in the rolling process vary with the type of products processed.

(1) During the whole production process of steel, continuous temperature measurement and frame adjustment of the descaling machine can ensure product quality and normal use of the production line, and avoid accidental shutdown.

(2) The billet of the rolling mill unit has been continuously cooled before entering the rolling mill. If the production line stops working for a period of time, the billet temperature may be lower than that before restart. This roller must be set to compensate for the corresponding changes in temperature.

The roll can be set manually by the operator, or an infrared thermometer can be installed in front of each rolling mill, and the rolling mill can be set automatically. This ensures that the mill is set correctly. In order to eliminate the influence of steam and dust in the control cooling area on temperature measurement, a two-color thermometer is used to accurately measure temperature even when the energy of the target is blocked by 95%.

(3) During the hot rolling process of the coiler, the normally cooled steel plate is rolled into steel coils by the coiler for transportation to the cold rolling or other equipment. In order to maintain the reasonable cooling of laminar cooling area, accurate temperature measurement is required at the coiler. The temperature at this point is crucial because it determines whether the steel is reasonably cooled before being rolled. Otherwise, unreasonable cooling may change the metallurgical properties of steel and cause scrap.

(4) Because the temperature of the coil box is low at this point and the steel is running at the speed of 75 ~ 100 feet / second, a low-temperature series infrared thermometer with fast response time is needed. Cold rolling is often carried out after finishing rolling and cooling, and the steel coil is transported to another plant for cold rolling or to other plants. Cold rolling makes the steel thinner and smoother. At this time, the steel is rolled at about 94 ℃ or at ambient temperature. The thermometer installed between finishing mills enables the operator to adjust the mill according to the detected temperature changes. Another high-speed processing process of bar / wire rolling is bar / wire rolling. The billets are reheated and sent to be rolled into bars.

After that, the bar is processed into different sizes through a series of intermediate rolling. After finishing rolling, the bar can be made into more than 100 different products. Reheating the billet to a uniform temperature is very important for the whole rolling process, because uneven bar temperature will aging the equipment and increase the maintenance downtime of the equipment. Knowing the product temperature between racks enables the operator to adjust the roll as required. When the product begins to enter the cooling zone, quickly and carefully monitor the cooling temperature to ensure the metallurgical performance of the product. If the cooling control is not good, the product cannot meet the requirements of process indicators, resulting in quality reduction or waste products. In some production processes, such as high-speed rolling and vibration of thin bars or wire products, temperature measurement is very difficult, infrared two-color thermometer can solve this problem. When the target deviates from the field of view or is partially blocked (dust, steam, obstacles, etc.), it can still accurately measure the temperature. The blast furnace hot blast stove provides high-temperature and stable hot air for the blast furnace.

In order to operate safely, it is necessary to monitor the dome temperature of the hot blast stove. At present, thermocouples are mostly used to measure the dome temperature of hot blast furnaces in China. Due to the limitations of the use environment (high temperature, high pressure) and structure of the thermocouple, the temperature fluctuates greatly. Under the influence of many factors such as vibration and installation mode, the service life of thermocouple is short. The measurement accuracy is unstable. Troublesome maintenance and other shortcomings. A special infrared temperature measurement protection device for hot blast stove dome temperature measurement can replace the thermocouple temperature measurement method to avoid many shortcomings caused by this method. The user's use results show that the device is stable, reliable and effective.

Applicable Machine

Infrared thermal imaging technology is widely used in industrial detection fields such as electric power, rail transit, equipment manufacturing and so on by virtue of the characteristics of full image surface accurate temperature measurement. With the continuous expansion of its application field, infrared thermal imaging technology also plays an important role in the detection and control process of metallurgical industry.

As one of the ferrous metallurgy, the iron and steel industry has developed towards refinement, intelligence and high quality after rough development. On the basis of ensuring the production capacity, the quality of steel has become an important indicator in the competition, and the purity of molten steel is very important.

In the process of steel production, converter steelmaking is an important part. When the steelmaking ends and the tapping begins, the molten steel flows into the ladle from the tapping port, and the liquid level of molten steel and slag in the furnace gradually decreases.

At the end of converter tapping, steel slag will also flow out with molten steel. Excessive steel slag will not only reduce the quality of molten steel, but also easily block the tapping hole, accelerate the wear of ladle refractory layer and shorten the service life of the equipment. Therefore, it is necessary to detect the slag situation of the converter in time, so as to stop slag or steel tapping in time.

Infrared application

The detection steps of tapping and slag of infrared thermal imaging converter are as follows:

1) Read the image, and preprocess the converter tapping image through denoising, enhancement and other algorithms;

2) Image region segmentation, a geometric active contour model for BOF tapping image is established, and the target contour curves of molten steel and slag and the average gray value of the segmented target region are obtained by solving the level set method;

3) Identification and content detection of steel slag, comparing the regional gray to determine the steel slag and calculate the steel slag content;

4) When the steel slag content reaches the set warning value, alarm and output signals to the converter control unit to stop the converter tapping in time, which can maximize the output of steel water and ensure the quality of steel.

Case analysis

Because the emissivity and temperature of steel slag generated in the steel-making process are obviously different from that of molten steel, the infrared thermal imager outputs the temperature image in real time, observes the outflow of steel slag, extracts the steel slag part by using the image segmentation technology and the given temperature threshold, calculates its proportion, and realizes the automatic control of the start and stop of steel tapping.

Advantage

1) The detection of converter steel slag by infrared thermal imaging technology is low cost and easy to maintain;

2) It can effectively avoid the disadvantages of low accuracy of traditional manual judgment and poor working environment of workers;

3) It has strong noise resistance and can realize rapid image segmentation and steel slag content detection;

4) Accurate and real-time automatic detection can improve the purity of molten steel and prolong the service life of the equipment.

Applicable Machine