A stable device for infrared temperature measurement of hot blast stove

Abstract

The utility model provides a kind of hot blast furnace infrared temperature measurement working condition stabilizing device, including infrared temperature measurement appearance, the infrared temperature measurement appearance is connected with upper sealing quartz mirror by upper connecting flange, the upper sealing quartz mirror is connected with electric heating coil through electric heating protection window, the electric heating coil is connected with lower sealing quartz mirror, the lower sealing quartz mirror is connected with nitrogen purging device, the nitrogen purging device is connected with high-temperature resistant through-hole ball valve, the high-temperature resistant through-hole ball valve is connected with angle adjuster, the angle adjuster is connected with peep tube, the peep tube is connected with lower connecting flange, the lower connecting flange is connected with hot blast furnace vault temperature measurement hole through welding short pipe.The utility model can make the working temperature where infrared temperature measurement appearance is at constant state, realize infrared temperature measurement appearance in high temperature, high dust, high humidity, multiple components, and flammable and explosive etc. Working condition long-term stable, reliable, accurate measurement.

Description

Technical Field

[0001] This utility model belongs to the field of instrumentation and measurement technology, and relates to a device for stabilizing the infrared temperature measurement working condition of a hot air furnace. Background Technology

[0002] Hot blast stoves are devices used to heat the blast air in blast furnaces and are an indispensable component of modern blast furnaces. Modern blast furnaces mostly use regenerative hot blast stoves. Their working principle involves first burning coal gas to heat the checker bricks in the regenerator chamber with the resulting flue gas. Then, cold air from the blast station is heated by passing it through the hot checker bricks. The hot blast stove alternately burns and supplies air, ensuring the blast furnace continuously receives high-temperature hot air. The temperature of the hot blast stove's dome is crucial data for the safe and accurate operation of the hot blast stove.

[0003] Traditionally, platinum-rhodium-platinum (S) or platinum-rhodium-platinum-rhodium (B) precious metal thermocouples are used for temperature measurement, with a measurement range of 0–1600℃. Due to the frequent changes in pressure and temperature inside the hot blast furnace during production, and the large thermal shock, the service life of the thermocouples is very short, ranging from a few weeks to a few months, which increases the cost of use and maintenance workload. In recent years, some metallurgical enterprises in China have gradually adopted non-contact infrared radiation thermometry technology for measuring the temperature of hot blast stove domes. However, in practical applications, due to various interference factors such as installation location, temperature, humidity, and weather, the measurement accuracy is low, with most measurement errors around ±4%F. In some cases, the error can even exceed ±10% when interference factors are not properly addressed. Continuous operation stability is also difficult to guarantee, requiring manual maintenance once a week. The main reasons for this are twofold: First, the influence of ambient temperature: most existing infrared radiation thermometry systems for hot blast stove domes in China use integrated infrared radiation thermometers. The measurement errors caused by temperature drift due to changes in ambient temperature have not received sufficient attention or been adequately addressed. For example, the Marathon thermometer produced by Raytheon in the United States... The MR1SBSF infrared thermometer has a system accuracy of ±0.75%FS, which refers to the accuracy of the instrument under standard operating conditions (temperature, humidity, etc.). However, when the ambient temperature exceeds the standard operating temperature, the silicon detector and electronic components inside the infrared thermometer are affected by the ambient temperature, and its measurement accuracy decreases according to the temperature coefficient (±0.03%FS / ambient temperature change in °C). Furthermore, the ambient temperature at the top of the hot blast stove is, in reality, highly variable due to seasonal variations, diurnal variations, meteorological conditions, and the insulation condition of the furnace lining. This makes it a location with significant temperature fluctuations and poor environmental conditions. If the infrared thermometer does not utilize... Effective insulation techniques and measures will inevitably introduce significant additional errors due to ambient temperature variations. Secondly, there is the impact of interference: Infrared radiation thermometry of the hot blast stove dome involves an optical path of approximately 3000–6000 mm between the thermometer and the target object, varying depending on the furnace type and size. This path can be divided into three parts: the external inspection tube, the temperature measurement holes in the furnace wall, and the flue gas flame zone at the furnace dome. Whether in combustion (at atmospheric pressure) or pressurized air supply mode, intermediate interfering media such as water vapor, CO2, dust, and smoke in the optical path attenuate the radiation energy of the target object through absorption, scattering, and reflection. The degree of influence depends on the amount of interfering media and the spectral response characteristics of the infrared radiation thermometer. Therefore, infrared radiation thermometry of the hot blast stove dome exhibits typical complex interference characteristics, presenting numerous challenges for comprehensive understanding and control. Utility Model Content

[0004] The purpose of this invention is to address the problems existing in the prior art by providing a device for stabilizing the infrared temperature measurement working conditions of a hot air furnace. This device solves the problem that existing infrared thermometers operate in environments with large temperature fluctuations, making it difficult to achieve long-term stable, reliable, and accurate measurements under complex environmental conditions.

[0005] Therefore, the present invention adopts the following technical solution:

[0006] A device for stabilizing the infrared temperature measurement operation of a hot blast stove includes an infrared thermometer. The infrared thermometer is connected to an upper sealing quartz lens via an upper connecting flange. The upper sealing quartz lens is connected to an electric heating coil via an electric heating protection window. The electric heating coil is connected to a lower sealing quartz lens. The lower sealing quartz lens is connected to a nitrogen purger. The nitrogen purger is connected to a high-temperature resistant through-hole ball valve. The high-temperature resistant through-hole ball valve is connected to an angle adjuster. The angle adjuster is connected to a viewing tube. The viewing tube is connected to a lower connecting flange. The lower connecting flange is connected to a temperature measuring hole on the dome of the hot blast stove via a welded short pipe.

[0007] Furthermore, the infrared thermometer is equipped with an aiming hole.

[0008] Furthermore, the infrared thermometer is equipped with a dust cover, and a heating rod and a thermal resistor are installed inside the dust cover.

[0009] Furthermore, the infrared thermometer is equipped with a protective case on its side, and the protective case contains a first power supply, a second power supply, and a temperature controller; wherein:

[0010] The first power supply is electrically connected to the infrared thermometer, and the second power supply is electrically connected to the electric heating coil.

[0011] Furthermore, the protective enclosure is provided with a gas source inlet, a nitrogen purge gas inlet, and a constant temperature dust cover gas inlet on its side; wherein:

[0012] The gas inlet is used to supply gas.

[0013] The nitrogen purger gas inlet is connected to the nitrogen purger via a shut-off valve.

[0014] The gas inlet of the constant temperature dust cover is used to connect the solenoid valve and the dust cover.

[0015] Furthermore, the gas source inlet and the nitrogen purger gas inlet are connected by a pipeline, and a gas source inlet shut-off valve, a filter pressure reducing valve, a gas flow stabilizing valve, a pressure gauge and a solenoid valve are sequentially installed between them.

[0016] Furthermore, the temperature controller is electrically connected to the heating rod, the resistance temperature detector, and the solenoid valve.

[0017] Furthermore, the dust cover is equipped with a convection adjustment window.

[0018] Furthermore, the first power supply uses a 24VDC power supply, and the second power supply uses a 36VAC power supply.

[0019] The beneficial effects of this utility model are as follows:

[0020] This invention enables the infrared thermometer to maintain a constant operating temperature of 20-30℃: when the temperature is ≤20℃, the temperature controller automatically starts the heating rod for heating; when the temperature is ≥30℃, the heating rod automatically stops heating; when the temperature is ≥40℃, the solenoid valve is automatically activated to control nitrogen gas for purging and cooling, thereby providing a stable operating environment for the infrared thermometer.

[0021] In addition, this utility model adopts a jacketed annular purger installed in the measuring optical path of the infrared thermometer, and the airflow outlet adopts an internal tangential nozzle design. Industrial nitrogen is used for continuous purging. A thermal shield is inserted between the instrument and the target to prevent dust, oil and water vapor from adhering to the optical lens. This enables the infrared thermometer to achieve long-term stable, reliable and accurate measurement under high temperature, high dust, high humidity (containing water), multi-component, flammable and explosive conditions. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of this utility model.

[0023] In the diagram, 1-Infrared thermometer, 2-Upper connecting flange, 3-Upper sealing quartz lens, 4-Electric heating protection window, 5-Electric heating coil, 6-Lower sealing quartz lens, 7-Nitrogen purger, 8-High temperature resistant through-hole ball valve, 9-Angle adjuster, 10-Sight tube, 11-Lower connecting flange, 12-Temperature measuring hole on the dome of the hot air furnace, 13-Aiming hole, 14-Heating rod, 15-Thermal resistance, 16-First power supply, 17-Second power supply, 18-Temperature controller, 19-Gas source, 20-Gas source inlet, 21-Gas source inlet shut-off valve, 22-Filter pressure reducing valve, 23-Gas flow stabilizing valve, 24-Pressure gauge, 25-Solenoid valve, 26-Stop valve, 27-Protective box, 28-Dust cover, 29-Convection adjustment window, 30-Nitrogen purger gas inlet, 31-Constant temperature dust cover gas inlet. Detailed Implementation

[0024] The technical solution of this utility model will be described below with reference to the accompanying drawings and implementation methods. Example

[0025] like Figure 1As shown, a device for stabilizing the infrared temperature measurement operation of a hot blast furnace includes an infrared thermometer 1. The infrared thermometer 1 is connected to an upper sealing quartz lens 3 via an upper connecting flange 2. The upper sealing quartz lens 3 is connected to an electric heating coil 5 via an electric heating protection window 4. The electric heating coil 5 is connected to a lower sealing quartz lens 6. The lower sealing quartz lens 6 is connected to a nitrogen purger 7. The nitrogen purger 7 is connected to a high-temperature resistant through-hole ball valve 8. The high-temperature resistant through-hole ball valve 8 is connected to an angle adjuster 9. The angle adjuster 9 is connected to a viewing tube 10. The viewing tube 10 is connected to a lower connecting flange 11. The lower connecting flange 11 is connected to a temperature measuring hole 12 on the dome of the hot blast furnace via a welded short pipe. Specifically, the nitrogen purger 7 has a jacketed annular structure, and the airflow outlet adopts an internal tangential nozzle (1.5mm×60°) design. Industrial nitrogen is used for continuous purging through the purging inlet.

[0026] The infrared thermometer 1 is equipped with an aiming hole 13, and the outer cover of the infrared thermometer 1 is equipped with a dust cover 28. The dust cover 28 is equipped with a convection adjustment window 29, and a heating rod 14 and a thermal resistor 15 are installed inside the dust cover 28. The infrared thermometer 1 is equipped with a protective box 27 on its side. The protective box 27 is equipped with a first power supply 16, a second power supply 17, and a temperature controller 18. Among them, the first power supply 16 is electrically connected to the infrared thermometer 1, and the second power supply 17 is electrically connected to the electric heating coil 5. The temperature controller 18 is electrically connected to the heating rod 14, the thermal resistor 15, and the solenoid valve 25 respectively. Specifically, the infrared thermometer 1 aims at the target along the mechanical axis. Therefore, through the aiming hole 13, the angle adjuster 9 is used to make the mechanical axis pass through the center of the target area to be measured. If there are interfering objects in the field of view, the angle adjuster 9 needs to be used to select the center of the target area.

[0027] The protective box 27 is provided with a gas source inlet 20, a nitrogen purger gas inlet 30 and a constant temperature dust cover gas inlet 31 on its side; wherein: the gas source inlet 20 is used to introduce the gas source 19; the nitrogen purger gas inlet 30 is connected to the nitrogen purger 7 through the shut-off valve 26; the constant temperature dust cover gas inlet 31 is used to connect the solenoid valve 25 and the dust cover 28.

[0028] The gas source inlet 20 and the nitrogen purger gas inlet 30 are connected by a pipeline, and a gas source inlet shut-off valve 21, a filter pressure reducing valve 22, a gas flow stabilizing valve 23, a pressure gauge 24, and a solenoid valve 25 are sequentially installed between them. In this embodiment, the filter pressure reducing valve 22 has a maximum working pressure of 1 MPa, a filtration accuracy of 5 μm, and a pressure adjustment range of 0.05 to 0.5 MPa. The filter pressure reducing valve 22 filters particles >5 μm in the nitrogen or compressed air source and reduces the pressure to 0.2 to 0.4 MPa. The gas source inlet shut-off valve 21 has a maximum withstand pressure of 1.6 MPa.

[0029] The first power supply 16 uses a 24VDC power supply and outputs a 4-20mA DC signal; the second power supply 17 uses a 36VAC power supply. When operating in winter, the second power supply 17 is turned on to defrost the upper sealed quartz lens 3 and the lower sealed quartz lens 6.

[0030] During use, this invention can maintain the working environment temperature of the infrared thermometer 1 at a constant 20-30℃. Specifically: when the temperature is ≤20℃, the temperature controller 18 automatically starts the heating rod 14 for heating; when the temperature is ≥30℃, the heating rod 14 automatically stops heating; when the temperature is ≥40℃, the solenoid valve 25 is automatically activated to control nitrogen gas for purging and cooling, thereby providing a stable working environment for the infrared thermometer.

[0031] In addition, this utility model uses a nitrogen purger 7 installed in the measuring optical path of the infrared thermometer 1. The airflow outlet adopts an internal tangential nozzle design and uses industrial nitrogen for continuous purging. A thermal shield is inserted between the instrument and the target to prevent dust, oil and water vapor from adhering to the optical lens. This enables the infrared thermometer 1 to achieve long-term stable, reliable and accurate measurement under high temperature, high dust, high humidity (containing water), multi-component, flammable and explosive conditions.

Claims

1. A device for stabilizing the infrared temperature measurement operation of a hot blast stove, characterized in that, The device includes an infrared thermometer (1), which is connected to an upper sealing quartz lens (3) via an upper connecting flange (2). The upper sealing quartz lens (3) is connected to an electric heating coil (5) via an electric heating protection window (4). The electric heating coil (5) is connected to a lower sealing quartz lens (6). The lower sealing quartz lens (6) is connected to a nitrogen purger (7). The nitrogen purger (7) is connected to a high-temperature resistant through-hole ball valve (8). The high-temperature resistant through-hole ball valve (8) is connected to an angle adjuster (9). The angle adjuster (9) is connected to a viewing tube (10). The viewing tube (10) is connected to a lower connecting flange (11). The lower connecting flange (11) is connected to a temperature measuring hole (12) on the top of the hot air furnace via a welded short pipe.

2. The infrared temperature measurement stabilization device for a hot blast stove according to claim 1, characterized in that, The infrared thermometer (1) is equipped with an aiming hole (13).

3. The infrared temperature measurement stabilization device for a hot blast stove according to claim 1, characterized in that, The infrared thermometer (1) is covered with a dust cover (28), and a heating rod (14) and a thermal resistor (15) are provided inside the dust cover (28).

4. The infrared temperature measurement stabilization device for a hot blast stove according to claim 3, characterized in that, The infrared thermometer (1) is provided with a protective box (27) on its side, and the protective box (27) contains a first power supply (16), a second power supply (17), and a temperature controller (18); wherein: The first power supply (16) is electrically connected to the infrared thermometer (1), and the second power supply (17) is electrically connected to the electric heating coil (5).

5. The infrared temperature measurement stabilization device for a hot blast stove according to claim 4, characterized in that, The protective box (27) is provided with a gas source inlet (20), a nitrogen purger gas inlet (30), and a constant temperature dust cover gas inlet (31) on its side; wherein: The gas inlet (20) is used to supply gas (19); The nitrogen purger gas inlet (30) is connected to the nitrogen purger (7) through a shut-off valve (26); The gas inlet (31) of the constant temperature dust cover is used to connect the solenoid valve (25) and the dust cover (28).

6. The infrared temperature measurement stabilization device for a hot blast stove according to claim 5, characterized in that, The gas source inlet (20) and the nitrogen purger gas inlet (30) are connected by a pipeline, and a gas source inlet shut-off valve (21), a filter pressure reducing valve (22), a gas flow stabilizing valve (23), a pressure gauge (24) and a solenoid valve (25) are installed between them in sequence.

7. The infrared temperature measurement stabilization device for a hot blast stove according to claim 4, characterized in that, The temperature controller (18) is electrically connected to the heating rod (14), the thermal resistor (15), and the solenoid valve (25), respectively.

8. The infrared temperature measurement stabilization device for a hot blast stove according to claim 3, characterized in that, The dust cover (28) is provided with a convection adjustment window (29).

9. The infrared temperature measurement stabilization device for a hot blast stove according to claim 4, characterized in that, The first power supply (16) uses a 24VDC power supply, and the second power supply (17) uses a 36VAC power supply.

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