A billet temperature detection system

Abstract

This invention discloses a billet temperature detection system, comprising: multiple thermocouples, a data acquisition unit, and a controller. The thermocouples are spaced apart within heat-resistant pads of a heating furnace to collect temperature signals when the billet is placed on the heat-resistant pads. The data acquisition unit is connected to the thermocouples and converts the temperature signals into temperature values, which are then sent to the controller. The controller constructs a temperature change model of the billet during heating in the furnace based on the temperature values. During heating, the billet is placed on the heat-resistant pads, and the thermocouples are fixed within them, allowing for stable measurement of the billet's bottom temperature. Furthermore, the multiple thermocouples distributed within the heat-resistant pads ensure continuous and stable temperature detection even as the billet moves horizontally across the pads, enabling the tracking of the billet's actual temperature changes. The controller then constructs a temperature change model of the billet during heating in the furnace based on the temperature values, thus revealing the billet's temperature variation patterns.

Description

Technical Field

[0001] This invention relates to the field of billet heating technology, and in particular to a billet temperature detection system. Background Technology

[0002] There are two main methods for measuring the temperature of steel billets in existing heating furnaces:

[0003] 1. Indirect measurement method: The temperature of the furnace atmosphere (the equilibrium temperature between the furnace gas, the furnace wall, and the steel billet) is measured by thermocouples as a reference for the steel billet temperature.

[0004] Indirect measurement methods involve installing thermocouples on the sides and top of the furnace body in the preheating, heating, and soaking sections of the heating furnace. However, since the billet is constantly moving inside the heating furnace, the temperature of the furnace atmosphere is related to the burner opening, air volume, and thermocouple insertion depth. Therefore, indirect measurement methods are difficult to reflect the true temperature of the billet and make it difficult to construct a data chart of the true temperature distribution of the billet inside the furnace.

[0005] 2. Measure the surface temperature of the steel billet: Measure the surface temperature of the steel billet using a non-contact method such as an infrared thermometer.

[0006] The method of measuring the surface temperature of steel billets needs to overcome the influence of high-temperature gases and various interferences in the furnace on the accuracy of the measurement. The measurement method is generally to insert a measuring probe into the heating furnace through the steel tapping port or other observation holes. The number of measurement points is small, making it difficult to track the actual temperature changes of the steel billets in the furnace. Summary of the Invention

[0007] This invention provides a billet temperature detection system to solve the problem that existing billet temperature measurements are difficult to reflect the true temperature of the billet due to different measurement factors or a limited number of temperature measurement points.

[0008] This invention provides a billet temperature detection system, comprising: multiple thermocouples, a data acquisition unit, and a controller.

[0009] The thermocouples are spaced apart in the heat-resistant pads of the heating furnace to collect temperature signals when the steel billet is placed on the heat-resistant pads.

[0010] The data acquisition unit is connected to the thermocouple and is used to convert the temperature signal into a temperature value and send it to the controller;

[0011] The controller is used to construct a temperature change model of the steel billet when it is heated in the heating furnace based on the temperature value.

[0012] The billet temperature detection system provided in this invention includes: multiple thermocouples, a data acquisition unit, and a controller. The thermocouples are spaced apart within heat-resistant pads in the heating furnace to collect temperature signals when the billet is placed on the heat-resistant pads. The data acquisition unit is connected to the thermocouples and converts the temperature signals into temperature values, which are then sent to the controller. The controller constructs a temperature change model of the billet during heating in the furnace based on these temperature values. During heating, the billet is placed on the heat-resistant pads, and the thermocouples are fixed within them, allowing for stable measurement of the billet's bottom temperature. Furthermore, the multiple thermocouples distributed within the heat-resistant pads ensure continuous and stable temperature detection even as the billet moves horizontally across the pads, enabling the tracking of the billet's actual temperature changes. The controller then constructs a temperature change model of the billet during heating in the furnace based on the temperature values, thus obtaining the billet's temperature change pattern.

[0013] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a flowchart of a billet temperature detection system provided in an embodiment of the present invention;

[0016] Figure 2 This is a top view of a heat insulation pad provided in an embodiment of the present invention;

[0017] Figure 3 This is a schematic diagram of a temperature change curve provided in an embodiment of the present invention. Detailed Implementation

[0018] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0019] Figure 1This is a flowchart of a billet temperature detection system provided in an embodiment of the present invention. This embodiment is applicable to the situation of billet temperature in a heating furnace. The heating furnace in this embodiment is a walking beam furnace. Figure 1 As shown, the heating furnace includes a furnace bottom 14, fixed beam columns 13, fixed beams 12, and heat-resistant pads 11, with the heat-resistant pads 11 located on the fixed beams 12. The process sections for heating the billet 40 in the heating furnace are divided into a preheating section, a heating section, and a soaking section. The specific equipment and control parameters differ for each process section. When the billet 40 needs to enter a process section or change process sections, it needs to be moved horizontally above the fixed beams 12 to enter different process sections. When the billet 40 is placed at the corresponding position of the target process section, it is lowered and placed on the heat-resistant pads 11 above the fixed beams 12. Specifically, when the billet 40 needs to enter or change process sections, a moving beam (not shown) in the heating furnace lifts the billet 40 to a certain height, moves it horizontally a certain distance, and then places it on the heat-resistant pads 11 before heating in that process section.

[0020] The billet temperature detection system provided in this embodiment of the invention includes: multiple thermocouples 10, a data acquisition unit 20 and a controller 30. The thermocouples 10 are spaced apart in the heat-resistant pads 11 of the heating furnace. The data acquisition unit 20 is connected to the thermocouples 10 and the controller 30 is connected to the data acquisition unit 20.

[0021] Thermocouples are used to collect temperature signals when a steel billet is placed on a heat-resistant pad. The working principle of a thermocouple is as follows: two different metal conductors are welded together to form a closed circuit. If a temperature difference is generated when the welded ends are heated, a thermoelectric potential (TEP) is generated in the circuit. If the temperature of the other end (considered as the reference end) is kept constant (typically 0°C), then the TEP of the circuit becomes a single-valued function of the temperature at the measuring end. This element, which measures temperature by measuring the TEP, consisting of two paired metal conductors, is called a thermocouple. The TEP generated by a thermocouple depends only on the thermoelectrode materials and the temperature difference between its two ends, and is independent of the length and diameter of the thermoelectrodes.

[0022] The detection end of the thermocouple is connected to the heat-resistant pad. When the steel billet is placed on the heat-resistant pad, the heat-resistant pad conducts heat and transfers the heat to the detection end of the thermocouple, forming a temperature difference with the other end of the thermocouple (considered as the reference end), which generates a thermoelectric potential and is connected to the data acquisition unit through the data line.

[0023] The data acquisition unit is used to convert temperature signals into temperature values ​​and send them to the controller. The data acquisition unit is essentially a signal converter, transforming the thermocouple's temperature signal into a machine-readable temperature value (digital signal) and sending it to the controller.

[0024] The controller is used to construct a temperature change model of the steel billet during heating in the furnace based on the temperature values. The controller is the calculation and control center of the entire furnace system. Thermocouples are distributed on heat-resistant pads, which can collect the temperature signals of the steel billet at different times. Therefore, the controller can obtain the temperature values ​​of the steel billet at different times, and then construct a temperature change model of the steel billet during heating in the furnace. Specifically, the temperature and time data can be plotted on a curve to obtain the temperature change model.

[0025] The controller can be equipped with a display to show the temperature values ​​sent by the data acquisition unit and the constructed temperature change model, making it easy for staff to view.

[0026] The billet temperature detection system provided in this invention includes: multiple thermocouples, a data acquisition unit, and a controller. The thermocouples are spaced apart within heat-resistant pads in the heating furnace to collect temperature signals when the billet is placed on the heat-resistant pads. The data acquisition unit is connected to the thermocouples and converts the temperature signals into temperature values, which are then sent to the controller. The controller constructs a temperature change model of the billet during heating in the furnace based on these temperature values. During heating, the billet is placed on the heat-resistant pads, and the thermocouples are fixed within them, allowing for stable measurement of the billet's bottom temperature. Furthermore, the multiple thermocouples distributed within the heat-resistant pads ensure continuous and stable temperature detection even as the billet moves horizontally across the pads, enabling the tracking of the billet's actual temperature changes. The controller then constructs a temperature change model of the billet during heating in the furnace based on the temperature values, thus obtaining the billet's temperature change pattern.

[0027] In an optional embodiment of the present invention, the thermocouple is an armored thermocouple. The protective tube of the armored thermocouple is made of a nickel-based high-temperature alloy, and the thermocouple core is made of platinum-rhodium 10-platinum. The nickel-based high-temperature alloy armored thermocouple can operate at a maximum temperature of 1300℃. The thermocouple is installed along the outer wall of the water beam pipe in the heating furnace. Under normal circumstances, the temperature of the outer wall of the water beam is around 130℃. The thermocouple is first insulated with a layer of fiber cotton, and then protected by castable refractory. Therefore, the armored thermocouple meets the condition of long-term operation at temperatures below 1300℃ inside the heating furnace. The thermocouple passes through the bottom of the heating furnace, through the fixed beam column, and connects with the heat-resistant pad in the hollow part of the fixed beam. When the thermocouple is horizontally installed in the fixed beam, the thermocouple is laid at the bottom of the fixed beam.

[0028] In an optional embodiment of the present invention, such as Figure 1As shown, the heat-resistant pad 11 equipped with a thermocouple 10 includes a base 112, a heat-insulating pad (not shown), and a heat-conducting pad 111, with the heat-insulating pad located between the base 112 and the heat-conducting pad 111. It should be noted that regardless of whether the heat-resistant pad 11 is equipped with a thermocouple 10, the upper surfaces of all heat-resistant pads 11 are flush, so that the steel billet 40 can be placed flat on the heat-resistant pad 11.

[0029] Among them, the heat-conducting pad has the characteristic of high thermal conductivity, which facilitates the transfer of heat from the steel billet to the thermocouple for temperature signal acquisition. For example, it can be a silicon nitride ceramic pad. Silicon nitride ceramic pads have excellent thermal conductivity and advantages such as high temperature resistance, oxidation resistance, high hardness, and wear resistance. Silicon nitride ceramics have excellent thermal conductivity, up to 155W / mK. The thermocouple is installed inside the silicon nitride ceramic pad. Since the steel billet in the walking beam furnace is supported on the fixed beam for 70% to -80% of the time, the temperature of the steel billet can be conducted to the thermocouple through the silicon nitride ceramic pad. Due to the heat insulation effect of the insulating pad, the problem of black marks on the steel billet can be eliminated.

[0030] Thermal insulation pads have the characteristic of low thermal conductivity; for example, they can be nanofiber thermal insulation pads.

[0031] The base can be a cobalt-based alloy base, for example, the cobalt-based alloy can be Co-50, Co-40, or Co-20.

[0032] Based on the furnace temperature distribution, the process sections along the length of the furnace can be divided into a preheating section, a heating section, and a soaking section. The heating section is the main heating section, with a higher furnace gas temperature to facilitate rapid heating. The soaking section is located at the discharge end, where the furnace gas temperature is very close to the metal material temperature, ensuring uniform cross-sectional temperature of the discharged billet. Considering the material and performance requirements of the base for different process sections, as well as equipment costs, a Co-50 cobalt-based alloy base can be used for the soaking section, while a Co-40 cobalt-based alloy base can be used for the heating section.

[0033] In an optional embodiment of the present invention, thermocouple mounting holes are provided on the base, the heat insulation pad, and the heat-conducting pad. One end of the thermocouple is fixedly connected to the heat-conducting pad through the thermocouple mounting holes on the base, the heat insulation pad, and the heat-conducting pad, while the other end of the thermocouple passes through the bottom of the heating furnace and is connected to the data acquisition device.

[0034] Taking thermal insulation gaskets as an example, such as Figure 2 As shown, Figure 2 This is a top view of the thermal insulation gasket, which has thermocouple mounting holes 113.

[0035] The thermocouple mounting holes on the base, insulating pad, and thermally conductive pad are the same size and aligned to allow the thermocouple to directly connect to the thermally conductive pad through these three holes. It should be noted that the thermocouple mounting holes on the base and insulating pad are through holes, while the thermocouple mounting holes on the thermally conductive pad are not required to be through holes, as long as the thermally conductive pad can properly transfer energy to the thermocouple. The thermocouple passes through the mounting hole on the base. A low thermal conductivity insulating pad is placed on top of the base, which also has a mounting groove for the thermally conductive pad. The thermally conductive pad is inserted along the mounting groove on the base, and the thermocouple is inserted into the bottom of the thermocouple mounting hole on the thermally conductive pad.

[0036] For armored thermocouples installed in the heating and heat-spreading sections, a high-alumina or corundum protective sleeve should be installed at a height of more than 1 meter from the fixed beam column and below the base. The thermocouples should be laid along the fixed beam and fixed beam column and fixed at appropriate locations. After the thermocouples are installed, the fixed beam and column should be wrapped with fiber cotton and then cast with refractory mortar. The part below the cobalt-based alloy base of the combined heat-resistant pad should be covered with refractory mortar.

[0037] High-alumina or corundum protective sleeves can operate for extended periods in oxidizing environments at 1500-1600℃, preventing thermocouple exposure due to refractory material detachment.

[0038] In an optional embodiment of the present invention, the horizontal distance between two adjacent thermocouples is equal to an integer multiple of the horizontal movement step length of the moving beam in the heating furnace. L is the horizontal movement step length of the moving beam in the heating furnace, and n is the number of steps of the moving beam. Therefore, the horizontal distance between two adjacent thermocouples is nL, where n is a positive integer.

[0039] That is, the thermocouples are placed on the heat-resistant pads on which the billet will be lowered. It should be noted that the first thermocouple should be located at the initial position when the billet enters the heating furnace. As long as the moving beam moves the billet horizontally a certain distance and places it on the heat-resistant pads, the temperature signal of the billet can be collected through the thermocouples.

[0040] In an optional embodiment of the present invention, the horizontal movement step length of the moving beam in the heating furnace and the width of the steel billet satisfy the relationship: nL / K=N,

[0041] Where L is the horizontal movement step size of the moving beam in the heating furnace, K is the width of the billet, n is the number of steps of the moving beam, and n and N are positive integers. That is, the horizontal movement distance of the moving beam is an integer multiple of the billet width, ensuring that the thermocouples on the heat-resistant pad correspond to the same position on the billet before and after the movement, guaranteeing consistent temperature detection conditions. Assuming that before the movement, the thermocouples correspond to the center position in the width direction of the billet, the billet width is 1.5m, and the horizontal movement step size of the moving beam is 2m, when the number of steps is 3, the horizontal movement distance of the billet is 6m, satisfying nL / K = N, where N is a positive integer. At this point, N = 4. Therefore, after the billet moves and lands on the heat-resistant pad, the thermocouples still correspond to the center position in the width direction of the billet. This means that temperature signals can be collected from the same position on the billet before and after the movement, avoiding errors caused by temperature differences at different positions.

[0042] To clearly illustrate the construction process of the temperature change model in this embodiment, the following example is used:

[0043] Assume the horizontal movement step of the walking beam furnace is L, and the distribution distance of the thermocouple measuring points on the fixed beam is set to NL, where N = 1, 2, 3, 4... Assume the width of the billet entering the furnace is K, and the horizontal movement distance of the furnace is nL, where n is the number of steps. Suppose a billet A is positioned at the first temperature detection point. If the horizontal movement distance of the furnace is nL, and the condition nL / K = N holds, then the sequence number of the thermocouple at the temperature measuring point corresponding to billet A at this time is N. Based on this setting, if the billets entering the furnace are A, B, C..., then the temperature values ​​A1, B1, C1... before the walking beam moves, and A2, B2, C2... after the movement, can be obtained according to the horizontal movement distance of the walking beam. Based on the distribution of billet temperature data at different time periods, a model of the billet temperature change within the furnace over time can be established.

[0044] In an optional embodiment of the present invention, the controller includes:

[0045] The temperature distribution data determination module is used to determine the temperature distribution data of the steel billet at different times, different process stages, and different horizontal movement distances based on the temperature data.

[0046] The model generation module is used to establish a temperature change model of steel billets during heating in a heating furnace based on the collected temperature distribution data of a preset number of steel billets.

[0047] In an optional example of the present invention, different process sections of the heating furnace correspond to different thermocouples, and the temperature distribution data determination module includes:

[0048] The time-arrangement submodule is used to arrange the temperature values ​​of each steel billet according to the acquisition time, obtaining the first distribution data. It should be noted that the thermocouples are spaced apart on the heat-resistant pads. Based on the order in which the steel billets pass over the heat-resistant pads, the time order in which each thermocouple acquires the temperature signal from the steel billet is related to the position of the thermocouple on the heat-resistant pad. Thermocouples positioned earlier will acquire the temperature signal of the steel billet first, and thermocouples positioned later will acquire it later. Typically, the acquisition order of the temperature values ​​corresponds to the setting order (serial number) of the thermocouples. For example, the first temperature signal is acquired by the first thermocouple, the second temperature signal is acquired by the second thermocouple, and so on.

[0049] The process segment arrangement submodule is used to mark the first distribution data with process segments based on the thermocouples corresponding to the process segments of the heating furnace, thereby obtaining the second distribution data. For example, if the thermocouples corresponding to the heating segments are numbered 5, 6, 7, and 8, then the temperature values ​​corresponding to the thermocouples numbered 5, 6, 7, and 8 in the first distribution data are marked with "heating segment".

[0050] The distance marking submodule is used to mark the horizontal movement distance of the second distribution data according to the installation position of the thermocouple in the heating furnace, so as to obtain the temperature distribution data of the billet at different times, different process sections, and different horizontal movement distances. The horizontal movement distance of the moving beam is monitorable, and the current process section can also be determined based on the horizontal movement distance of the moving beam. For example, when the horizontal movement distance is 2m, it can be determined that the billet has entered the preheating section, so the heating equipment in the preheating section can be controlled.

[0051] In this embodiment, temperature data is marked with time, process segment, and horizontal movement distance, making the temperature data information more diversified and conducive to building a more complete temperature change model.

[0052] In an optional embodiment of the present invention, the model building module includes:

[0053] The initial model building module is used to build the initial model. The variable parameters of the initial model include time, process segment, horizontal movement distance, and temperature.

[0054] The model training submodule is used to input a preset amount of temperature distribution data into the initial model and fit it to obtain a temperature change model.

[0055] The temperature change model is the fitted temperature change curve, for example, such as Figure 3 As shown, Figure 3The temperature curves of different steel billets at different times, different process stages, and different horizontal movement distances are the temperature change curves before fitting. The data can be segmented and fitted according to each process stage to obtain the time-temperature change law for that process stage, thus obtaining the fitted temperature change curve, i.e., the temperature change model. It should be noted that... Figure 3 The temperature curves shown are for illustrative purposes only. The data in the figures are not intended to limit the invention. In actual production, the curves should be set according to the equipment, parameters, and temperature data of the heating furnace.

[0056] In an optional embodiment of the present invention, the controller further includes:

[0057] The parameter control module is used to control the furnace atmosphere temperature, burner opening, and air volume based on a temperature change model. In other words, the controller guides the furnace control parameters during the billet heating process based on the temperature change pattern of the billet within the furnace, facilitating automated production.

[0058] In an optional embodiment of the present invention, the controller further includes a model calibration module, used to calibrate the constructed temperature change model based on new temperature values ​​sent by the data acquisition unit. The more data available, the higher the accuracy and adaptability of the temperature change model; therefore, new temperature data can be continuously accumulated to correct the temperature change model.

[0059] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0060] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A billet temperature detection system, characterized in that, include: Multiple thermocouples, data acquisition units, and controllers, The thermocouples are spaced apart in the heat-resistant pads of the heating furnace to collect temperature signals when the steel billet is placed on the heat-resistant pads. The data acquisition unit is connected to the thermocouple and is used to convert the temperature signal into a temperature value and send it to the controller; The controller is used to construct a temperature change model of the steel billet when it is heated in the heating furnace based on the temperature value; The horizontal distance between two adjacent thermocouples is equal to an integer multiple of the horizontal movement step length of the moving beam in the heating furnace; The controller includes: The temperature distribution data determination module is used to determine the temperature distribution data of the steel billet at different times, different process sections, and different horizontal moving distances based on the temperature data. The model generation module is used to establish a temperature change model of the steel billet when it is heated in the heating furnace based on the collected temperature distribution data of a preset number of steel billets. Different process sections of the heating furnace correspond to different thermocouples, and the temperature distribution data determination module includes: The time arrangement submodule is used to arrange the temperature values ​​according to the acquisition time for each steel billet to obtain the first distribution data; The process segment arrangement submodule is used to mark the first distribution data according to the thermocouples corresponding to the process segments of the heating furnace to obtain the second distribution data; The distance marking submodule is used to mark the horizontal movement distance of the second distribution data according to the installation position of the thermocouple in the heating furnace, so as to obtain the temperature distribution data of the billet at different times, different process sections and different horizontal movement distances.

2. The billet temperature detection system as described in claim 1, characterized in that, The heat-resistant pad with the thermocouple includes a base, a heat-insulating pad, and a heat-conducting pad, with the heat-insulating pad located between the base and the heat-conducting pad.

3. The billet temperature detection system as described in claim 2, characterized in that, The base, the heat insulation pad, and the heat-conducting pad are all provided with thermocouple mounting holes; One end of the thermocouple is fixedly connected to the heat-conducting pad via the thermocouple mounting hole on the base, the heat insulation pad, and the heat-conducting pad. The other end of the thermocouple passes through the bottom of the heating furnace and is connected to the data acquisition device.

4. The billet temperature detection system as described in claim 1, characterized in that, The horizontal movement step length of the moving beam in the heating furnace and the width of the steel billet satisfy the relationship: nL / K=N. Where L is the horizontal movement step length of the moving beam in the heating furnace, K is the width of the steel billet, n is the number of steps of the moving beam, and n and N are positive integers.

5. The billet temperature detection system as described in claim 1, characterized in that, The model building module includes: The initial model building module is used to build an initial model, whose variable parameters include time, process segment, horizontal movement distance, and temperature. The model training submodule is used to input a preset amount of the temperature distribution data into the initial model and fit it to obtain a temperature change model.

6. The billet temperature detection system according to any one of claims 1-5, characterized in that, The controller also includes: The parameter control module is used to control the furnace atmosphere temperature, burner opening and air volume of the heating furnace according to the temperature change model.

7. The billet temperature detection system according to any one of claims 1-5, characterized in that, The controller also includes: The model calibration module is used to calibrate the constructed temperature change model based on the new temperature values ​​sent by the data acquisition device.

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