System and method for measuring the temperature of the sprayed ingot surface and the tundish molten steel

Abstract

The present invention discloses a system and method for measuring the temperature of the sprayed ingot surface and tundish molten steel. During the spray molding process, the tundish is measured, and a point temperature meter is used to collect the center temperature of the spray surface. A thermal imager collects the temperatures of multiple fixed areas on the same radial direction of the spray surface for measurement, and the temperature is corrected using the collected temperatures using the point temperatures. Simultaneously, a tundish temperature collector collects the tundish molten steel temperature. The above temperature data is collected at set intervals, and the collected temperature data is refreshed once at set intervals. When ten sets of data are accumulated, the temperatures collected by the point temperature meter and the corrected temperature values of multiple areas of the thermal image are averaged. Simultaneously, the current tundish molten steel temperature and the sprayed ingot surface height value are collected and arranged into a line of character strings for storage. The present invention realizes online measurement of the sprayed ingot spray surface temperature and the tundish molten steel temperature.

Description

Technical Field

[0001] The invention belongs to the technical field of automatic detection and provides a system and method for measuring the temperature of the upper end surface of a cylindrical injection ingot (hereinafter referred to as the injection surface) and the temperature of molten steel in a tundish. Background Art

[0002] The spray ingot is to spray the molten steel back and forth along the radius of the end face of the cylindrical ingot through two nozzles onto a circular tray. The tray spirally descends at a constant speed so that the spray surface remains at a certain height. After the molten steel is converted from liquid to solid, a complete cylindrical steel ingot is formed, which is located inside a hollow cylindrical protective cover.

[0003] The spraying process is relatively rare in the industry, and automatic temperature measurement systems are even more lacking. The temperature of the spray surface during spraying is extremely important for the shaping and quality control of the steel ingot. On the one hand, the current method is to manually measure the temperature of the tundish at five-minute intervals using a handheld thermal thermometer. During spraying, the steel ingot is located on the center tray of the hollow protective cover, making it impossible to directly measure the temperature of the spray surface. On the other hand, the thermometer is a disposable product with high consumption, and handheld measurement requires close contact with the high-temperature environment, which is dangerous. Therefore, it is necessary to develop a non-contact spray surface temperature measurement and a contact-type tundish molten steel temperature measurement device to achieve automatic temperature measurement and provide a data foundation for the spraying process. Summary of the Invention

[0004] The purpose of the present invention is to provide a system and method for measuring the temperature of the injection surface and the temperature of the tundish. For steel ingots with a diameter between 500-800mm, the temperatures of the tundish, the center of the injection surface and multiple fixed areas in the same radial direction are measured during the injection molding process, and the data are collected, analyzed and stored, thereby realizing online measurement of the injection surface temperature of the injection ingot and the molten steel temperature in the tundish.

[0005] The system for measuring the temperature of the spray ingot surface and the tundish molten steel comprises a point temperature meter, a thermal imager, a tundish temperature collector, a spray ingot protection cover, a carbon rod medium, a temperature probe protection bucket, a tundish, a switch and an industrial control machine.

[0006] The point temperature meter is used to collect the temperature of the center point of the injection surface, and the data is transmitted to the switch through the network cable.

[0007] The thermal imager is connected to the switch via a network cable and is used to obtain the average temperature within three areas with a pixel size of 20X20, selected from the center area of the injection surface at equal pixel intervals along the radius of the injection surface; the three areas are the center area of the injection surface, the center area of the injection surface radius, and the outer end area of the injection surface radius.

[0008] The temperature probe of the tundish temperature collector is connected to the top of the carbon rod medium; the carbon rod medium is inserted into the opening at the center of the bottom surface of the tundish temperature probe protection bucket, so that the carbon rod medium is inserted into the molten steel, and the tundish temperature probe measures the temperature of the molten steel in the tundish; the tundish temperature collector is connected to the serial port of the industrial computer through an RS485-RS232 converter, and the temperature of the molten steel in the tundish measured by the temperature probe is sent to the industrial computer.

[0009] The switch is connected to the network port of the industrial computer through a network cable and is used to transmit the collected data of the point temperature meter and the thermal imager to the industrial computer.

[0010] The industrial computer is used to control the entire temperature measurement process.

[0011] Based on the above-mentioned temperature measurement method of the sprayed ingot surface temperature and the tundish molten steel temperature measurement system, the specific steps are as follows:

[0012] Step 1: System Initialization

[0013] System initialization includes:

[0014] A. Call the thermal image acquisition block function to generate three 20x20 pixel areas in the thermal imager;

[0015] B. Start the point temperature data receiving thread.

[0016] Step 2: Parameter Setting

[0017] Manually input the furnace number, ingot number, diameter, steel type, length, superheat, and height increase speed to set the parameters. After confirming that they are correct, proceed to step 3.

[0018] Step 3: Temperature measurement, including tundish temperature data measurement, point temperature data measurement, thermal imaging temperature measurement and temperature calculation.

[0019] Among them, the method for obtaining the intermediate ladle temperature data is: establish serial port communication between the industrial computer and the intermediate ladle temperature collector, open the serial port, continuously obtain the intermediate ladle temperature data string through the serial port interrupt function, then calculate the temperature data, and display the intermediate ladle temperature data in the system interface, and generate a dynamic line chart at the same time.

[0020] The point temperature data measurement method is: call the point temperature communication function and establish TCP / IP communication through socket; at the same time, set the point temperature meter collection time interval to 2s in the industrial computer, and send temperature acquisition instructions to the point temperature meter with a period of 2s; then the point temperature meter obtains the ingot surface center point temperature data string every 2s, and solves the ingot surface center point temperature data string through the point temperature data receiving process, and extracts the ingot surface center point temperature value from the ingot surface center point temperature data string.

[0021] The thermal image temperature measurement method is as follows: the industrial computer calls the thermal image acquisition block function of the thermal imager, and further calls the thermal image temperature acquisition function. The thermal imager collects the average temperature according to the set three 20x20 area element coordinates.

[0022] Step 4: Calculate the thermal image temperature correction value

[0023] Calculate the difference between the temperature value of the center point of the ingot surface at time t and the average temperature value of the corresponding position measured by the thermal imager to obtain the difference Δx t :

[0024] Δx t =C t -P1 t

[0025] Among them, C t P1 is the temperature value of the center point of the ingot surface measured by the point temperature instrument 1 at time t; t is the average temperature of the central area of the injection surface measured by the thermal imager at time t.

[0026] The difference Δx t Sum the three area averages measured by the thermal imager, and the result is the correction value of the three area averages, that is:

[0027] T1 t =P1 t +Δx t =C t ;

[0028] T2 t =P2 t +Δx t ;

[0029] T3 t =P3 t +Δx t ;

[0030] Among them, T1 t T2 is the correction value of the average temperature of the central area of the injection surface at time t; t T3 is the correction value of the average temperature of the center area of the injection surface radius at time t; t P2 is the correction value of the average temperature of the outer end area of the injection surface radius at time t; t P3 is the average temperature of the center area of the injection surface measured by the thermal imager at time t; t is the average temperature of the outer end area of the injection surface radius measured by the thermal imager at time t.

[0031] The advantages of the present invention are:

[0032] 1. The injection surface temperature and tundish molten steel temperature measurement system of the present invention meets the needs of long-term data measurement / display / storage / playback / export;

[0033] 2. The present invention's method for measuring the injection surface temperature and tundish molten steel temperature uses a point temperature meter, a thermal imager, and a tundish continuous temperature meter as primary measuring equipment. An online measurement and analysis system for injection surface temperature data and tundish molten steel temperature data is designed and implemented, overcoming the shortcomings of manual measurement of data points, insufficient data volume, and a harsh measurement environment. The system ensures that the measured data reaches stability within five minutes of the start of injection.

[0034] 3. The injection surface temperature and tundish molten steel temperature measuring system of the present invention is easy to use, cost-effective and easy to promote. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Schematic diagram of the system for measuring the temperature of the sprayed ingot surface and the tundish molten steel temperature according to the present invention.

[0036] Figure 2 This is a flow chart of the method for measuring the temperature of the sprayed ingot surface and the tundish molten steel temperature of the present invention.

[0037] In the picture:

[0038] 1-Point temperature meter 2-Thermal imager 3-Tundish temperature collector

[0039] 4- Spray ingot protective cover 5- Carbon rod medium 6- Temperature probe protection bucket

[0040] 7-Middle package 8-Switch 9-Industrial computer

[0041] 301-Temperature probe DETAILED DESCRIPTION

[0042] The present invention will be described in further detail below with reference to the accompanying drawings.

[0043] The injection surface temperature and tundish molten steel temperature measurement system of the present invention is composed of a point temperature meter 1, a thermal imager 2, a tundish temperature collector 3, a spray ingot protective cover 4, a carbon rod medium 5, a temperature probe protection bucket 6, a tundish 7, a switch 8 and an industrial computer 9. Figure 1 As shown, Figure 1 shown.

[0044] The spot temperature meter 1 uses an E1RL-F2-V-0-018 infrared thermometer (600-1800°C dual-color, eyepiece / video aiming, and captures single-point temperature values). It has a high-temperature protective sleeve E-GSTJ1 (cast aluminum, water-cooled, and air-purged), and an adjustable mounting bracket E-GSAB for the protective sleeve. The spot temperature meter 1 is placed in the protective sleeve and mounted on one side of the upper end of the spray ingot protective cover 2 via the bracket. The spray ingot protective cover 4 has a circular window on the side and is isolated from the outside world by heat-resistant glass. The spot temperature meter 1 can collect the temperature (spot temperature data) of the center point of the spray surface through the glass. The data from the spot temperature meter 1 is transmitted to the switch 8 via a network cable.

[0045] Thermal imager 2 uses an OPTPI1MLOF25T1800 infrared thermal imager (with a response wavelength of 0.92-1.1μm and collects area array temperature values). It is equipped with a SUB-to-Ethernet signal converter (model ACPIUSBSGB) and a 315°C protective cover with a SUB-to-Ethernet signal converter mounting point (model ACPICJAEU). It also features a protective window for the thermal imager cover (model ACCJAPWPI1M) and a front adjustment unit for the cover (model ACCJAFUOF25). Thermal imager 2 is mounted on the upper end of the spraying ingot protective cover 4, on the same level as and opposite to the spot temperature meter 1. Thermal imager 2 is connected to switch 8 via a network cable to collect the spraying surface temperature. Starting from the center of the spraying surface, three 20x20 pixel areas are selected at equal pixel intervals along the spraying surface radius, and the average temperature of each area is calculated. The three areas, from the inside out, are the center of the spraying surface, the center of the spraying surface radius, and the outer end of the spraying surface radius.

[0046] The tundish temperature collector 3 uses a WFD-600-LXCW type molten steel continuous temperature detector, which has a temperature probe 301, an RS485-RS232 converter 302, a display instrument and a display instrument protection box.

[0047] The temperature probe 301 is connected to the top of the carbon rod medium 5. The outer diameter of the carbon rod medium 5 gradually decreases from the top to the bottom. The carbon rod medium 5 is inserted into the central opening on the bottom surface of the tundish temperature probe protection bucket 6. The carbon rod medium 5 is positioned by the large diameter of the top. The tundish temperature probe bucket 6 is placed on the upper rectangular opening of the tundish 7, with the carbon rod medium 5 inserted approximately 300 mm below the molten steel. The tundish temperature probe 301 measures the molten steel temperature within the tundish. The tundish temperature probe 301 is connected to the tundish temperature collector 3 via a metal hose. The tundish temperature collector 3 is connected to the serial port of the industrial computer 9 via an RS485-RS232 converter 302. The tundish temperature collector 3 collects the molten steel temperature within the tundish 7 measured by the tundish temperature probe 301 and transmits it to the industrial computer for storage.

[0048] The switch 8 uses an industrial switch 105TX (5-port 10 / 100BaseTX Industrial Ethernet Switch, DIN-Rail) and has an on-site electrical box with power terminals, as well as power and communication cables (required length of 40 meters, one for the thermometer, one for the power supply and communication cables, and one for the thermal imager, and one for the power supply and communication cables). The switch 8 is connected to the network port of the industrial computer 9 via a network cable to transmit the collected data from the spot temperature meter 1 and thermal imager 2 to the industrial computer 9.

[0049] The industrial computer 9 uses an i7-7700 processor with a quad-core processor at 3.4GHz, 8GB of RAM, and a 1GB mechanical hard drive and a 128GB solid-state drive. It controls the entire temperature measurement process and includes a playback module and a temperature measurement module.

[0050] Among them, the playback module is used to call the stored data and display it in the system interface to realize the playback of the measured temperature data and the current workpiece specification parameters; and the playback target in the playback data can be selected in sequence. By selecting the target to be played back, the target furnace number, ingot number, diameter, steel type, length, superheat, height increase speed setting parameters corresponding to the MySQL database and the measured temperature data are called and displayed in the system interface. The playback module has a zoom adjustment function for the playback data to adjust the density of the playback data. The revisit module also has a data export function to realize the export of measurement data, and by setting the start time and end time, the historical data of this time period can be exported to the Output folder, generating an Excel file named with the start time and end time (containing multiple steel ingots) and a temperature data file in txt format. To view, you only need to open the Excel file, and the data column is set with a hyperlink to the txt file.

[0051] The temperature measurement module allows you to set parameters such as the ingot furnace number, ingot number, diameter, steel type, length, superheat, and height increase rate. Once set, the module checks whether the parameters are correct. If they are incorrect, an error message will be displayed on the system interface. If they are correct, the measurement will begin. The measurement results will be displayed on the system interface at regular intervals and stored. The measurement will end when the ingot spraying is complete.

[0052] Based on the above-mentioned measurement method of the injection surface temperature and the tundish molten steel temperature measurement system, such as Figure 2 The specific steps are as follows:

[0053] Step 1: System initialization.

[0054] System initialization includes:

[0055] A. Call the thermal image acquisition block function to generate three 20x20 matrices (thermal image acquisition blocks) in thermal imager 2. The starting coordinates of the three matrices are (46, 142), (146, 142), and (246, 142), respectively. The matrix element value is the coordinate of the current element.

[0056] B. Call the MySQL database and display the last furnace number, ingot number, diameter, steel type, length, superheat, height increase speed setting parameters and temperature measurement data on the system interface.

[0057] C. Start the point temperature data receiving thread.

[0058] Step 2: Parameter Setting

[0059] Manually input the furnace number, ingot number, diameter, steel type, length, superheat, and height increase speed to set the parameters. After confirming that they are correct, proceed to step 3.

[0060] Step 3: Temperature measurement, including tundish temperature data measurement, point temperature data measurement, thermal imaging temperature measurement and temperature calculation.

[0061] Among them, the method for obtaining the intermediate ladle temperature data is: establishing serial port communication between the industrial computer 9 and the intermediate ladle temperature collector 3, opening the serial port, continuously obtaining the intermediate ladle temperature data string through the serial port interrupt function, and then performing temperature data calculation, and displaying the intermediate ladle temperature data in the system interface, and generating a dynamic line graph at the same time.

[0062] The point temperature data measurement method is: call the point temperature communication function and establish TCP / IP communication through the socket; at the same time, set the point temperature meter 1 collection time interval to 2s in the industrial computer 9, and send the temperature acquisition instruction to the point temperature meter 1 with a period of 2s; then the point temperature meter 1 obtains the ingot surface center point temperature data string at a regular interval of 2s, and solves the ingot surface center point temperature data string through the point temperature data receiving process, and extracts the ingot surface center point temperature value from the ingot surface center point temperature data string.

[0063] The thermal image temperature measurement method is as follows: the industrial computer calls the thermal image acquisition block function of thermal imager 2, and further calls the thermal image temperature acquisition function. Thermal imager 2 performs average temperature acquisition based on the set three 20x20 thermal image acquisition block element coordinates.

[0064] Step 4: Calculate the thermal image temperature correction value

[0065] Calculate the difference between the temperature value of the center point of the ingot surface at time t measured by the thermometer 1 and the average temperature value of the corresponding position (the center area of the injection surface) measured by the thermal imager 2 to obtain the difference Δx t :

[0066] Δx t=C t -P1 t

[0067] Among them, C t P1 is the temperature value of the center point of the ingot surface measured by the point temperature instrument 1 at time t; t is the average temperature of the center area of the injection surface measured by the thermal imager at time t. t >P1 t .

[0068] The difference Δx t The sum of the three area averages measured by thermal imager 2 is the correction value of the three area averages, that is:

[0069] T1 t =P1 t +Δx t =C t ;

[0070] T2 t =P2 t +Δx t ;

[0071] T3 t =P3 t +Δx t ;

[0072] Among them, T1 t T2 is the correction value of the average temperature of the central area of the injection surface at time t; t T3 is the correction value of the average temperature of the center area of the injection surface radius at time t; t P2 is the correction value of the average temperature of the outer end area of the injection surface radius at time t; t P3 is the average temperature of the center area of the injection surface measured by the thermal imager at time t; t is the average temperature of the outer end area of the injection surface radius measured by the thermal imager at time t.

[0073] Step 5: Temperature data display and storage

[0074] A set of data is acquired every 2 seconds, including spot temperature data, temperature correction values for the three zones of the thermal image, the tundish molten steel temperature value, and the current height of the sprayed ingot surface. A line graph of the three zones of the thermal image is generated based on the temperature correction values for the three zones of the thermal image. The spot temperature values, tundish molten steel temperature values, current height of the sprayed ingot surface, and the line graph of the three zones of the thermal image are displayed on the system interface and refreshed every 2 seconds. When ten sets of data are accumulated, the spot temperature values and the corrected temperature values for the three zones of the thermal image are averaged. At the same time, the current tundish molten steel temperature value and the sprayed ingot surface height value are collected and arranged into a line of strings for storage.

Claims

1. A method for measuring the temperature of a sprayed ingot surface and a tundish molten steel temperature measuring system, characterized in that: The specific steps are as follows: Step 1: System Initialization System initialization includes: A. Call the thermal image acquisition block function to generate three 20x20 pixel areas in the thermal imager; B. Start the point temperature data receiving thread; Step 2: Parameter Setting Manually input the furnace number, ingot number, diameter, steel type, length, superheat, and height increase speed setting parameters. After confirming that they are correct, proceed to step 3; Step 3: Temperature measurement, including tundish temperature data measurement, point temperature data measurement, thermal imaging temperature measurement and temperature calculation; The method for acquiring tundish temperature data is as follows: serial communication is established between the industrial computer and the tundish temperature collector, the serial port is opened, and the tundish temperature data string is continuously acquired through the serial port interrupt function. The temperature data is then calculated and displayed on the system interface, and a dynamic line chart is generated. The point temperature data measurement method is as follows: calling the point temperature communication function and establishing TCP / IP communication through a socket; at the same time, the industrial computer sets the point temperature meter acquisition time interval to 2 seconds, and then sends a temperature acquisition instruction to the point temperature meter at a 2-second period; then the point temperature meter acquires the ingot surface center point temperature data string every 2 seconds, and the point temperature data receiving process performs the calculation to extract the ingot surface center point temperature value from the ingot surface center point temperature data string; The thermal image temperature measurement method is as follows: the industrial computer calls the thermal image acquisition block function of the thermal imager, and further calls the thermal image temperature acquisition function. The thermal imager collects the average temperature based on the coordinates of the three 20x20 area elements set; Step 4: Calculate the thermal image temperature correction value Calculate the difference between the temperature value of the center point of the ingot surface at time t and the average temperature value of the corresponding position measured by the thermal imager to obtain the difference Δx t : Δx t =C t -P1 t Among them, C t P1 is the temperature value of the center point of the ingot surface measured by the point temperature meter at time t; t is the average temperature of the central area of the injection surface measured by the thermal imager at time t; The difference Δx t Sum the three area averages measured by the thermal imager, and the result is the correction value of the three area averages, that is: T1 t =P1 t +Δx t =C t ; T2 t =P2 t +Δx t ; T3 t =P3 t +Δx t ; Among them, T1 t T2 is the correction value of the average temperature of the central area of the injection surface at time t; t T3 is the correction value of the average temperature of the center area of the injection surface radius at time t; t P2 is the correction value of the average temperature of the outer end area of the injection surface radius at time t; t P3 is the average temperature of the center area of the injection surface measured by the thermal imager at time t; t is the average temperature of the outer end area of the injection surface radius measured by the thermal imager at time t; A set of data is acquired every 2 seconds, including point temperature data, temperature correction values of the three areas of the thermal image, temperature value of the molten steel in the tundish, current height of the sprayed ingot surface, and a broken line graph of the three areas of the thermal image generated based on the temperature correction values of the three areas of the thermal image; among them, the point temperature value, temperature value of the molten steel in the tundish, current height value of the sprayed ingot surface and the broken line graph of the three areas of the thermal image are displayed in the system interface and refreshed every 2 seconds. When ten sets of data are accumulated, the point temperature value and the corrected temperature value of the three areas of the thermal image are averaged respectively. At the same time, the current temperature value of the molten steel in the tundish and the height value of the sprayed ingot surface are collected and arranged into a row of character strings for storage.

2. A method for measuring the temperature of the sprayed ingot surface temperature and the tundish molten steel temperature measuring system according to claim 1, characterized in that: In step 1, system initialization also includes calling the MySQL database to display the last furnace number, ingot number, diameter, steel type, length, superheat, height increase speed setting parameters and temperature measurement data measured on the system interface.

3. A system for measuring the temperature of the sprayed ingot surface and the tundish molten steel temperature according to claim 1, characterized in that: It consists of a spot temperature meter, a thermal imager, a tundish temperature collector, a spray ingot protection cover, a carbon rod medium, a temperature probe protection bucket, a tundish, a switch and an industrial control unit. The point temperature meter is used to collect the temperature of the center point of the injection surface, and the data is transmitted to the switch via the network cable; The thermal imager is connected to a switch via a network cable and is used to obtain the average temperature of three 20×20 pixel areas selected from the center of the injection surface at equal pixel intervals along the radius of the injection surface; the three areas are the center of the injection surface, the center of the injection surface radius, and the outer end of the injection surface radius; The temperature probe of the tundish temperature collector is connected to the top of the carbon rod medium; the carbon rod medium is inserted into the opening at the center of the bottom surface of the tundish temperature probe protection bucket, so that the carbon rod medium is inserted into the molten steel, and the tundish temperature probe measures the temperature of the molten steel in the tundish; the tundish temperature collector is connected to the serial port of the industrial computer through an RS485-RS232 converter, and the temperature of the molten steel in the tundish measured by the temperature probe is sent to the industrial computer; The switch is connected to the network port of the industrial computer via a network cable, and is used to transmit the collected data of the point temperature meter and the thermal imager to the industrial computer; The industrial computer is used to control the entire temperature measurement process.

4. A system for measuring the temperature of the sprayed ingot surface and the tundish molten steel temperature as claimed in claim 3, characterized in that: The industrial computer has a playback module and a temperature measurement module. The playback module is used to call the stored data and display it in the system interface. The playback target in the playback data can be selected in sequence. By selecting the target to be played back, the corresponding target furnace number, ingot number, diameter, steel type, length, superheat, height increase speed setting parameters and measured temperature data in the MySQL database are called and displayed in the system interface. The playback module has a zoom adjustment function for the playback data to adjust the density of the playback data. The revisit module also has a data export function to realize the export of measurement data. By setting the start time and end time, the historical data of this time period can be exported. The temperature measurement module is used to set the parameter information of the steel ingot furnace number, ingot number, diameter, steel type, length, superheat, and height increase speed; after the setting is completed, the temperature measurement module detects whether the set parameters are correct; if the set parameters are incorrect, an error prompt will be given in the system interface; if the set parameters are correct, the measurement will be started; the measurement results will be displayed in the system interface at a certain time interval and stored; when the steel ingot spraying is completed, the measurement can be ended.

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