PF line heat preservation vestibule device and controlled cooling method

Abstract

The invention provides a PF line heat preservation vestibule device and a controlled cooling method, and belongs to the field of heat preservation equipment for production. The device comprises a heat preservation vestibule side wall, a top cover, a swing window, an electric skylight, a sliding door and a heating device. The side walls and the top cover of the heat preservation vestibule are welded into a frame through steel plates with the thickness of 3-5 mm, the two layers of rock wool heat preservation plates with the thickness of 50-80 mm are tightly stuffed into the frame, and the heat preservation vestibule is jointly defined. The swing window is installed at the lower end of the side wall, connected through a welding type hinge and provided with a windproof hook and a spring cotter. The electric skylight is arranged on the top cover, the sliding door is arranged on one side of the side wall, and the edge is provided with a sealing rubber strip. The heating device is located in the vestibule, an electromagnetic or infrared heating technology is adopted, the power is 10-20 kW, and a temperature sensor with the precision being + / -0.5 DEG C is arranged. The device solves the problems that a conventional PF line only depends on natural or simple air cooling, and the cooling speed cannot be accurately regulated and controlled.

Description

Technical Field

[0001] The invention relates to the technical field of heat preservation equipment for production, and in particular to a PF line heat preservation corridor device and a cooling control method. Background Art

[0002] In the steel production process, the hot-rolled wire rod is transferred from the coil collection station equipment to the slow cooling roller bed area, and then the coil is hung on the C-hook of the PF line by the coil transport vehicle through the flip roller bed. The coil then follows the C-hook through the packaging station, weighing station, and unloading station. At present, the domestic PF line mainly realizes the accumulation, cooling and transportation functions of the coil. However, in the production of special steel, due to the strict requirements of special steel on the internal organizational structure, the cooling speed of the coil needs to be precisely controlled to optimize the internal structure. Conventional PF lines only rely on natural cooling or simple air cooling methods, and cannot accurately control the cooling speed, making it difficult to meet the needs of special steel production. This leads to deficiencies in the mechanical properties of the produced special steel, which restricts the development of steel companies in the field of high-end products. Summary of the invention

[0003] In view of this, the present invention provides a PF line heat preservation corridor device, which specifically includes: a heat preservation corridor side wall, a heat preservation corridor top cover, a swing window, an electric skylight, a sliding door and a heating device;

[0004] The side wall of the insulation corridor is a rectangular box frame welded by a steel plate with a thickness of 3-5 mm, and a double-layer rock wool insulation board is tightly stuffed inside the rectangular box frame, and the thickness of each layer of rock wool insulation board is 50-80 mm;

[0005] The insulation corridor top cover is welded from a steel plate with a thickness of 3-5 mm into a special-shaped box frame, and a double-layer rock wool insulation board is tightly stuffed inside the special-shaped box frame, and each layer of rock wool insulation board is 50-80 mm thick. The insulation corridor side wall and the insulation corridor top cover together form an insulation corridor;

[0006] The swing windows are evenly installed at the lower end of the side wall of the insulation corridor. Each swing window is composed of a rectangular box frame welded from a steel plate with a thickness of 2-3 mm. 3-5 welded hinges are welded above the swing window. The hinges are fixed to the upper frame. A windproof hook is arranged above the swing window, and a spring latch is arranged below.

[0007] The electric skylights are evenly arranged on the top cover of the thermal insulation corridor;

[0008] The sliding door is arranged on one side of the side wall of the insulation corridor, and is welded into a frame by profiles and steel plates with a thickness of 3-5 mm, and a sealing strip is installed on the edge of the sliding door;

[0009] The heating device is installed in the inner space of the insulation corridor, adopts electromagnetic heating or infrared heating technology, has a power of 10-20kW, and is equipped with a temperature sensor with an accuracy of ±0.5°C.

[0010] Furthermore, the welded hinge has a length of 80-100 mm and a width of 30-40 mm; the windproof hook is made of stainless steel and has a length of 50-70 mm; and the spring latch has an insertion depth of 15-20 mm.

[0011] Furthermore, the sliding door has a height of 2-2.5 m and a width of 1-1.5 m.

[0012] Furthermore, the electric skylight comprises: a welded box frame, a roller, a guide groove and an electric push rod; the welded box frame is installed in the interior of the insulation corridor which is jointly surrounded by the side walls of the insulation corridor and the top cover of the insulation corridor, the roller is installed on the welded box frame, the guide groove is arranged in the interior of the insulation corridor which is jointly surrounded by the side walls of the insulation corridor and the top cover of the insulation corridor, the roller rolls in the guide groove, the electric push rod is connected to the welded box frame and provides it with power for opening and closing; the swing window in the open state and the electric skylight in the open state form a convection channel.

[0013] Furthermore, the roller has a diameter of 80-100 mm and is made of high-strength polyurethane; the guide groove has a length of 1-2 m and an accuracy controlled within ±0.5 mm; the electric push rod has a thrust of 500-1000 N and a stroke of 300-500 mm.

[0014] A cooling control method for a PF line insulation corridor specifically includes: heating and insulation after shutdown for maintenance, temperature control during normal production, intelligent adjustment under different production processes and emergency handling of abnormal situations.

[0015] Furthermore, the heating and insulation after shutdown and maintenance include: after shutdown and maintenance, 30 minutes before the first roll of special steel enters the insulation corridor, the heating device starts preheating; the intelligent control system collects data from temperature sensors at 5 different positions in the insulation corridor in real time, takes the average value as the initial temperature T0, and obtains the external environment temperature Te at the same time;

[0016] According to the heat loss model of the insulation corridor pre-entered into the system, the intelligent control system calculates the heat Q required to heat the corridor to the target temperature; the formula is: $Q=mc(T-T0)+kA(T-Te)t$, where m is the mass of the air in the corridor, c is the specific heat capacity of the air, T is the target temperature of 35°C, k is the total heat transfer coefficient of the insulation material, A is the total surface area of ​​the corridor, and t is the expected heating time of 20 minutes;

[0017] According to the heat Q and the thermal efficiency η of the heating device, the power P that the heating device needs to output is calculated: $P=\frac{Q}{\etat}$; the system automatically adjusts the power of the heating device accordingly, so that the temperature inside the insulation corridor rises to 35°C at a uniform rate within 20 minutes; during the heating process, the temperature sensor collects data every 2 minutes, and the intelligent control system fine-tunes the heating power in real time according to the deviation between the actual heating curve and the preset curve to ensure the stability of the heating process;

[0018] After reaching the target temperature, the temperature sensor continuously monitors the temperature in a 1-minute cycle; if the temperature fluctuation exceeds ±1°C, the intelligent control system adjusts the power of the heating device according to the PID control algorithm based on the positive and negative and size of the temperature deviation.

[0019] Furthermore, temperature control during normal production includes:

[0020] During normal production, five temperature sensors evenly distributed in the insulation corridor monitor the temperature in real time with a cycle of 30 seconds. When any of the sensors detects that the temperature exceeds 35°C, the intelligent control system immediately starts the cooling program.

[0021] The system first calculates the average temperature Tavg and the temperature standard deviation σ in the corridor based on data from multiple temperature sensors; if Tavg is between 35-37°C and σ<2°C, it indicates that the temperature rise is relatively uniform, and the intelligent control system controls the electric sunroof to open to 30° and the swing window to open to 20°; if Tavg is between 37-38°C and σ<3°C, the electric sunroof opens to 45° and the swing window opens to 30°; if Tavg ≥38°C or σ≥3°C, the electric sunroof and swing window are fully opened;

[0022] During the ventilation and cooling process, the temperature sensor continuously feeds back data; the intelligent control system recalculates Tavg and σ based on the new temperature data in a 1-minute cycle, and adjusts the opening angles of the electric sunroof and swing window according to the fuzzy control algorithm;

[0023] When the temperature drops to 32℃, the intelligent control system begins to gradually reduce the opening angles of the electric sunroof and swing window; first reduce the opening angles of the electric sunroof and swing window by 10° at the same time, and observe the temperature changes within 5 minutes. If the temperature is stable or rises slightly and remains between 30-32℃, maintain the current opening angle; if the temperature continues to drop, continue to reduce the opening angle by 5° each time until the temperature stabilizes within the range of 30-40℃.

[0024] Furthermore, intelligent adjustments under different production processes include:

[0025] The system pre-stores a variety of cooling curve templates for different special steel production processes; before production, the operator selects the corresponding cooling curve template according to the type of special steel actually produced, and the intelligent control system adjusts the temperature control strategy according to the selected template;

[0026] The intelligent control system dynamically adjusts the ventilation strategy according to the conveying speed of the coils on the production line; when the coil conveying speed increases, the opening angle of the ventilation equipment is increased according to the speed increase ratio; when the conveying speed slows down, the opening angle is reduced according to the speed reduction ratio to ensure that each coil can be accurately cooled.

[0027] Furthermore, emergency response to abnormal situations includes:

[0028] During the entire cooling control process, the intelligent control system monitors the equipment status and temperature data in real time; if the data collected by a temperature sensor fluctuates abnormally for three consecutive times or deviates from the data of other sensors by more than ±3°C, the system immediately starts the backup temperature sensor and sends the number and fault information of the faulty sensor to the operator's terminal device, notifying the maintenance personnel to carry out maintenance;

[0029] If the current of the electric push rod exceeds 120% of the rated current when the electric skylight or swing window is opening or closing, the intelligent control system will first try to send 3 different control instructions. If the problem is still not solved, the system will immediately shut down the equipment and start the backup ventilation equipment. At the same time, the system will adjust the power of the heating device according to the current temperature and the remaining cooling time to maintain the temperature in the insulation corridor within the allowable fluctuation range.

[0030] Beneficial effects:

[0031] Precise cooling control improves steel performance: Compared with the existing conventional PF wire suspension line, the insulation corridor system of the present invention increases the insulation and cooling control operation space, and can accurately control the cooling speed and cooling time of the coil. Through precise control, the austenite structure state and phase change product state inside the wire are effectively optimized, and the mechanical properties of the steel, such as strength, toughness, wear resistance, etc., are significantly improved, so that the quality of the produced special steel reaches higher standards and meets the strict requirements of high-end manufacturing for special steel.

[0032] In addition, efficient insulation saves energy and reduces consumption: the side walls and top cover of the insulation corridor adopt a combination structure of high-quality steel plates and double-layer rock wool insulation boards, which has excellent insulation performance. In different seasons and ambient temperatures, it can effectively reduce heat transfer and reduce energy consumption. For example, in the cold winter environment, it can greatly reduce heat loss, maintain a stable temperature inside the insulation corridor, and reduce the energy consumption of the heating device; in the high temperature summer environment, it can effectively block the entry of external heat, reduce the load of ventilation and cooling, achieve the goal of energy saving and consumption reduction, and improve the economic benefits of the enterprise.

[0033] In addition, flexible ventilation can adapt to various working conditions: the large number of swing windows and electric skylights and the flexible opening and closing control methods make the ventilation and heat dissipation functions more flexible and efficient. Through the intelligent control system, the ventilation volume and convection speed can be accurately adjusted according to different production process requirements, ambient temperature and humidity and other factors. When producing different types of special steel, the ventilation strategy can be quickly adjusted to ensure that the cooling process meets the process requirements, which improves the adaptability and versatility of the system and meets the diversified production needs of steel companies.

[0034] In addition, convenient maintenance ensures stable operation of the system: the reasonable design of the sliding door and the intelligent control of the internal heating device provide great convenience for the maintenance and operation of the system. The sliding door facilitates personnel to enter and exit the insulation corridor, conduct daily inspection, maintenance and repair of internal equipment, and promptly discover and solve potential problems to ensure stable operation of the system. The intelligent control function of the heating device not only ensures the cooling quality of special steel, but also reduces the workload of operators and improves production efficiency.

[0035] In addition, filling the technical gap and promoting the development of the industry: the technical solution of the present invention fills the technical gap in the field of PF line insulation corridor system and cooling control method at home and abroad, and provides a new and efficient cooling control solution for the steel and metallurgical industry. The application of this technology is conducive to promoting the upgrading of special steel production technology of steel enterprises, improving the competitiveness of my country's steel industry in the international market, and promoting the sustainable development of the industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the drawings of the embodiment are briefly introduced below.

[0037] The drawings described below are only related to some embodiments of the present invention, but are not intended to limit the present invention.

[0038] In the attached picture:

[0039] Figure 1 It is a structural schematic diagram of a PF line heat preservation corridor device provided in an embodiment of the present invention;

[0040] Figure 2 is a schematic diagram of sliding door connection provided by an embodiment of the present invention;

[0041] Figure 3 It is a schematic diagram of the connection of the electric sunroof provided in an embodiment of the present invention.

[0042] Figure 4 It is a schematic diagram of the first part of the system flow of an embodiment of the present invention.

[0043] Figure 5 It is a schematic diagram of the second part of the system flow of an embodiment of the present invention.

[0044] Figure 6 It is a schematic diagram of the system flow of the third part of an embodiment of the present invention.

[0045] Reference numerals list

[0046] 1. Insulated corridor side wall; 2. Insulated corridor roof; 3. Swinging window; 4. Electric skylight; 401. Welded box frame; 402. Roller; 403. Guide groove; 404. Electric push rod; 5. Sliding door. DETAILED DESCRIPTION

[0047] The embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings and examples.

[0048] Example: Please refer to Figures 1 to 6 As shown:

[0049] The present invention provides a PF line heat preservation corridor device, comprising: a heat preservation corridor side wall 1, a heat preservation corridor top cover 2, a swing window 3, an electric skylight 4, a sliding door 5 and a heating device;

[0050] The insulation corridor side wall 1 is a rectangular box frame welded from a steel plate with a thickness of 3-5 mm. A double-layer rock wool insulation board is tightly stuffed into the rectangular box frame, and each layer of rock wool insulation board is 50-80 mm thick.

[0051] The insulation corridor top cover 2 is welded from a steel plate with a thickness of 3-5 mm into a special-shaped box frame, and a double-layer rock wool insulation board is tightly stuffed inside the special-shaped box frame. The thickness of each layer of rock wool insulation board is 50-80 mm. The insulation corridor side wall 1 and the insulation corridor top cover 2 together form an insulation corridor;

[0052] The swing windows 3 are evenly installed at the lower end of the insulation corridor side wall 1. Each swing window 3 is composed of a rectangular box frame welded from a steel plate with a thickness of 2-3 mm. 3-5 welded hinges are welded above the swing window 3. The hinges are fixed to the upper frame. A windproof hook is arranged above the swing window 3, and a spring latch is arranged below.

[0053] The electric skylights 4 are evenly arranged on the top cover 2 of the thermal insulation corridor;

[0054] The sliding door 5 is arranged on one side of the insulation corridor side wall 1, and is welded into a frame by profiles and steel plates with a thickness of 3-5 mm, and a sealing strip is installed on the edge of the sliding door 5;

[0055] The heating device is installed in the internal space of the insulation corridor. It adopts electromagnetic heating or infrared heating technology, has a power of 10-20kW, and is equipped with a temperature sensor with an accuracy of ±0.5℃.

[0056] Among them, the welded hinge is 80-100mm long and 30-40mm wide; the windproof hook is made of stainless steel and is 50-70mm long; the spring pin insertion depth is 15-20mm.

[0057] The sliding door 5 has a height of 2-2.5 m and a width of 1-1.5 m.

[0058] Among them, the electric skylight 4 includes: a welded box frame 401, a roller 402, a guide groove 403 and an electric push rod 404; the welded box frame 401 is installed in the insulation corridor side wall 1 and the insulation corridor top cover 2 together form the interior of the insulation corridor, the roller 402 is installed on the welded box frame 401, the guide groove 403 is arranged in the insulation corridor side wall 1 and the insulation corridor top cover 2 together form the interior of the insulation corridor, the roller 402 rolls in the guide groove 403, the electric push rod 404 is connected to the welded box frame 401 and provides it with power to open and close; the swing window 3 in the open state and the electric skylight 4 in the open state form a convection channel.

[0059] Among them, the roller diameter is 80-100mm, and the material is high-strength polyurethane; the guide groove length is 1-2m, and the accuracy is controlled within ±0.5mm; the thrust of the electric push rod is 500-1000N, and the stroke is 300-500mm.

[0060] A cooling control method for a PF line insulation corridor is characterized by comprising: heating and insulation after shutdown for maintenance, temperature control during normal production, intelligent adjustment under different production processes and emergency handling of abnormal situations.

[0061] Among them, the heating and insulation after shutdown and maintenance include: after the shutdown and maintenance, the heating device starts preheating 30 minutes before the first roll of special steel enters the insulation corridor. The intelligent control system collects data from temperature sensors at 5 different positions in the insulation corridor (evenly distributed at the upper, middle, lower heights and both ends of the corridor) in real time, takes the average value as the initial temperature T0, and obtains the external environment temperature Te at the same time (obtained through networking with the factory environment monitoring system, or measured by a high-precision temperature sensor installed outside the corridor, with an accuracy of ±0.2℃).

[0062] According to the heat loss model of the insulation corridor pre-entered into the system (the model is established based on the dimensions of the corridor, the thermal conductivity of the insulation material, the surface area and other parameters, and has been optimized through multiple actual tests), the intelligent control system calculates the heat Q required to heat the corridor to the target temperature. The formula is: $Q=mcT-T0+kAT-Tet$, where m is the mass of the air in the corridor (calculated by the corridor volume and air density), c is the specific heat capacity of the air, T is the target temperature of 35°C (the default value, which can be adjusted within the range of 30-40°C according to the special steel process requirements), k is the total heat transfer coefficient of the insulation material, A is the total surface area of ​​the corridor, and t is the expected heating time of 20 minutes.

[0063] According to the heat Q and the thermal efficiency η of the heating device (known parameters, such as the thermal efficiency of the electromagnetic heating device is 90%), the power P that the heating device needs to output is calculated: $P=\frac{Q}{\etat}$. The system automatically adjusts the power of the heating device accordingly, so that the temperature inside the insulation corridor rises to 35°C at a uniform rate within 20 minutes. During the heating process, the temperature sensor collects data every 2 minutes, and the intelligent control system fine-tunes the heating power in real time according to the deviation between the actual heating curve and the preset curve to ensure the stability of the heating process.

[0064] After reaching the target temperature, the temperature sensor continuously monitors the temperature in a 1-minute cycle. If the temperature fluctuation exceeds ±1°C, the intelligent control system adjusts the power of the heating device according to the positive and negative and size of the temperature deviation according to the PID control algorithm. For example, when the temperature is higher than 36°C, the heating power value that needs to be reduced is calculated based on the deviation, so that the heating device reduces the power output; when the temperature is lower than 34°C, the heating power is increased to maintain the temperature stable between 30-40°C.

[0065] Among them, temperature control during normal production includes:

[0066] During normal production, five temperature sensors evenly distributed in the insulation corridor monitor the temperature in real time with a cycle of 30 seconds. When any of the sensors detects that the temperature exceeds 35°C, the intelligent control system immediately starts the cooling program.

[0067] The system first calculates the average temperature Tavg and the temperature standard deviation σ in the corridor based on the data from multiple temperature sensors. If Tavg is between 35-37℃ and σ<2℃, it indicates that the temperature rise is relatively uniform, and the intelligent control system controls the electric sunroof to open to 30° and the swing window to open to 20°; if Tavg is between 37-38℃ and σ<3℃, the electric sunroof opens to 45° and the swing window opens to 30°; if Tavg≥38℃ or σ≥3℃, the electric sunroof and swing window are fully opened.

[0068] During the ventilation and cooling process, the temperature sensor continuously feeds back data. The intelligent control system recalculates Tavg and σ based on the new temperature data in a 1-minute cycle, and adjusts the opening angles of the electric sunroof and swing window according to the fuzzy control algorithm. For example, when Tavg decreases slowly and σ is large, the opening angle of the vent is appropriately increased; when Tavg decreases too quickly and approaches 32°C, the opening angle is gradually reduced.

[0069] When the temperature drops to 32°C, the intelligent control system begins to gradually reduce the opening angles of the electric sunroof and swing window. First, reduce the opening angles of the electric sunroof and swing window by 10° at the same time, and observe the temperature changes within 5 minutes. If the temperature is stable or slightly rises and remains between 30-32°C, maintain the current opening angle; if the temperature continues to drop, continue to reduce the opening angle by 5° each time until the temperature stabilizes within the range of 30-40°C.

[0070] Among them, intelligent adjustments under different production processes include:

[0071] The system pre-stores a variety of cooling curve templates for different special steel production processes. Before production, the operator selects the corresponding cooling curve template according to the type of special steel actually produced, and the intelligent control system adjusts the temperature control strategy according to the selected template.

[0072] For example, for special steel A that requires rapid cooling, when the temperature reaches 38°C, the intelligent control system quickly opens the electric sunroof and swing window completely, and dynamically adjusts the ventilation time according to the temperature drop rate. If the temperature drop rate is lower than the process requirement of 2°C / minute, the system appropriately extends the ventilation time; if it is higher than 3°C / minute, some vents are closed in advance.

[0073] For special steel B that requires slow cooling, when the temperature exceeds 35°C, the electric sunroof opens to 15°, the swing window opens to 10°, and the intelligent control system strictly controls the temperature drop rate within 1°C / minute. By accurately adjusting the opening angle of the vents and the auxiliary heating power of the heating device, the cooling process is ensured to meet the process requirements.

[0074] At the same time, the intelligent control system dynamically adjusts the ventilation strategy according to the conveying speed of the coils on the production line (obtained through the speed sensor installed on the PF line, with an accuracy of ±0.1m / s). When the coil conveying speed increases, the opening angle of the ventilation equipment is increased accordingly according to the speed increase ratio; when the conveying speed slows down, the opening angle is reduced according to the speed reduction ratio to ensure that each coil can be accurately cooled.

[0075] Among them, emergency response to abnormal situations includes:

[0076] During the entire cooling control process, the intelligent control system monitors the equipment status and temperature data in real time. If the data collected by a temperature sensor fluctuates abnormally for three consecutive times (the fluctuation range exceeds ±5°C) or the deviation from other sensor data exceeds ±3°C, the system will immediately start the backup temperature sensor and send the fault sensor number and fault information to the operator's terminal device (such as mobile phone, computer), notifying the maintenance personnel to carry out maintenance.

[0077] If the electric sunroof or swing window is opening or closing, and the electric push rod current exceeds 120% of the rated current (indicating possible jamming or other faults), the intelligent control system will first try to send 3 different control commands (5 seconds between each command). If the problem is still not solved, the system will immediately shut down the device and start the backup ventilation equipment (if any). At the same time, the system adjusts the power of the heating device according to the current temperature and the remaining cooling time to maintain the temperature in the insulation corridor within the allowable fluctuation range (±3°C), ensuring that the cooling process of the special steel is not seriously affected, and ensuring the continuity of production and product quality.

[0078] PF line insulation corridor system performance test data:

[0079] 1. Purpose of the experiment

[0080] Comprehensively evaluate the performance of the PF line insulation corridor system under different conditions, including the ability to accurately control the cooling rate of the coil, the temperature uniformity during the cooling process, and the impact on the internal structure and mechanical properties of the special steel wire, to provide a detailed experimental basis for the optimization and practical application of the system.

[0081] 2. Experimental Equipment and Materials

[0082] PF line insulation corridor system: built according to patented technical specifications, the specific parameters of each part are as follows:

[0083] Insulated corridor side wall: 3mm thick high-quality steel plate is welded into a rectangular box frame, and the inside is tightly filled with double-layer 50mm thick rock wool insulation board to ensure good thermal insulation performance.

[0084] Insulated corridor roof: It is welded from 3mm thick steel plates into a specific special-shaped box frame, and is also filled with double-layer 50mm rock wool insulation boards to effectively block heat loss.

[0085] Swing window: A rectangular frame made of 2mm thick steel plate with 3 welded hinges welded on the top, equipped with windproof hooks and spring latches to ensure stability and sealing when opening and closing.

[0086] Electric sunroof: It consists of a welded box frame, matching rollers, guide grooves and electric push rods to achieve flexible opening and closing operations.

[0087] Sliding door: It is welded from high-strength profiles and 3mm thick steel plates, with sealing strips installed on the edges to enhance the sealing of the insulation corridor.

[0088] Heating device: Equipped with a 10kW heating device with a temperature control accuracy of ±1°C, ensuring precise regulation of the internal temperature.

[0089] Experimental steel: A specific type of special steel coil was selected as the experimental material, with a total of 15 groups, each containing 5 coils. Before the experiment, the initial temperature of the coils was controlled at 900℃ to ensure the consistency of the experimental conditions.

[0090] Measuring instruments: Equipped with a high-precision infrared thermometer (measuring accuracy of ±1°C) to monitor the temperature changes of the coil in real time; an electronic universal testing machine to accurately measure the tensile strength, yield strength and other mechanical properties of steel; a metallographic microscope to conduct microscopic observation of the austenite structure morphology and phase change products inside the steel.

[0091] 3. Experimental plan

[0092] 3.1 Cooling speed test under different seasonal ambient temperatures

[0093] Summer working conditions (simulated ambient temperature 35℃, relative humidity 60%): turn off the heating device, and fully open all swing windows and electric skylights to form natural convection between the insulation corridor and the outside environment. Every 10 minutes, use an infrared thermometer to measure the temperature at multiple locations on the coil surface, record the data, draw the coil cooling curve, and analyze its cooling rate.

[0094] Winter working conditions (simulated ambient temperature -5℃, relative humidity 40%): Start the heating device to maintain the temperature inside the insulation corridor at 35℃, close the swing windows and electric skylights to reduce heat loss. Measure the coil temperature every 15 minutes, monitor the cooling of the coil under this condition, and evaluate the system's control effect on the cooling speed in a low temperature environment.

[0095] 3.2 Cooling uniformity test under different ventilation strategies

[0096] Strategy 1: Open only one side of the swing window and the corresponding electric sunroof to simulate partial ventilation. Three groups of coils were selected for testing, and multiple temperature sensors were arranged at different positions of the coils to collect temperature data in real time. During the experiment, the temperature of each point was recorded every 10 minutes, and the uniformity of coil cooling was evaluated by calculating the temperature standard deviation.

[0097] Strategy 2: Open the swing windows on both sides and all electric skylights at the same time to achieve the maximum ventilation condition. Three groups of coils were selected and the same temperature monitoring method as strategy 1 was used to compare the differences in coil cooling uniformity under different ventilation strategies.

[0098] Strategy 3: Open the swing window and electric skylight at intervals to simulate a more flexible ventilation mode. Test the other three groups of coils, record the temperature data and calculate the temperature standard deviation to analyze the impact of this ventilation strategy on cooling uniformity.

[0099] 3.3 Test on the influence of internal structure and mechanical properties of wire

[0100] Organization structure analysis: Samples are cut from coils treated with different cooling conditions and processed according to standard metallographic preparation technology to make metallographic samples. The samples are observed using a metallographic microscope to analyze the morphology, grain size and distribution of phase transformation products of the austenite structure, and to study the influence of cooling rate on the organization structure.

[0101] Mechanical property test: Use an electronic universal testing machine to conduct tensile and impact tests on the samples. In the tensile test, key indicators such as tensile strength and yield strength of steel are measured; in the impact test, the impact toughness of steel is measured. By comparing the mechanical property data of the samples under different cooling conditions, the effect of the PF line insulation corridor system on the mechanical properties of special steel is evaluated.

[0102] 4. Experimental Results and Analysis

[0103] 4.1 Cooling speed test results

[0104] Summer working conditions: Under the summer simulated working conditions, it only takes 30 minutes for the coil temperature to drop from 900℃ to 600℃, and the average cooling rate reaches 10℃ / min. This is mainly because the ambient temperature is high in summer, and the temperature difference between the inside and outside of the insulation corridor is small. After opening the swing window and electric skylight, natural convection can quickly take away the heat of the coil, achieving rapid cooling, meeting the requirements of special steel for higher cooling speed in certain production processes.

[0105] Winter working conditions: In the winter simulation environment, it took 60 minutes for the coil to cool from 900℃ to 800℃, with an average cooling rate of 1.67℃ / min. In this low-temperature environment, the heating device continued to work, compensating for the heat lost due to heat dissipation, which significantly slowed down the cooling speed of the coil, meeting the process requirements of slow cooling of special steel in specific production stages, and effectively avoiding internal structural defects caused by too fast cooling.

[0106] 4.2 Cooling uniformity test results

[0107]

[0108] In strategy 1, due to limited ventilation and uneven airflow distribution, there are large differences in the heat exchange rate of different parts of the coil, the temperature standard deviation reaches 12.5°C, and the cooling uniformity is poor. Strategy 2 achieves maximum ventilation, and the airflow can flow through all parts of the coil more evenly. The temperature standard deviation is only 5.2°C, the cooling uniformity is good, and the consistency of the overall quality of the coil is effectively guaranteed. The ventilation method of strategy 3 is relatively flexible, but the ventilation volume and airflow uniformity are not as good as strategy 2. The temperature standard deviation is 8.7°C, and the cooling uniformity is at a medium level.

[0109] 4.3 Test results of organizational structure and mechanical properties

[0110] Organization structure: When the cooling rate is controlled within the appropriate range, the metallographic microscope observes that the austenite organization is transformed into uniform and fine grains, the phase change products are evenly distributed, and there are no obvious organizational defects. This shows that under this cooling condition, the internal organization structure of the steel is optimized, laying the foundation for good mechanical properties. However, when the cooling rate is too fast, the austenite does not have time to fully transform, resulting in a coarse and uneven organization, more residual austenite, and reduced steel performance. If the cooling rate is too slow, the grains will grow, which will also affect the overall performance of the steel.

[0111] Mechanical properties: After precise cooling control, the tensile strength of the sample reaches 1200MPa, the yield strength is 900MPa, and the impact toughness is 50J / cm 2 , showing good mechanical properties. However, the tensile strength of the sample with improper cooling process control was only 1000MPa, the yield strength was 750MPa, and the impact toughness was reduced to 30J / cm 2 This fully proves that the PF line insulation corridor system significantly improves the mechanical properties of special steel. Only by accurately controlling the cooling rate can the steel obtain an ideal organizational structure and thus improve its mechanical properties.

[0112] 5. Experimental conclusion:

[0113] The PF line insulation corridor system can effectively control the coil cooling speed in different seasonal ambient temperatures. In the high temperature environment in summer, it can achieve rapid cooling; in the low temperature environment in winter, it can meet the process requirements of slow cooling of special steel, providing a reliable cooling control method for special steel production.

[0114] Different ventilation strategies have a significant impact on the uniformity of coil cooling. The ventilation strategy of fully opening the double-side swing windows and all electric skylights can make the cooling of all parts of the coil more uniform, effectively improving the consistency of product quality. However, partial ventilation or interval ventilation strategies have certain limitations in cooling uniformity.

[0115] This system has a crucial impact on the internal structure and mechanical properties of special steel wire. By precisely controlling the cooling rate, it can optimize the austenite structure state and phase transformation product distribution, significantly improve the tensile strength, yield strength and impact toughness of steel and other mechanical properties, and meet the strict requirements of high-end manufacturing industry for special steel quality.

[0116] Specific usage and function of this embodiment: In the present invention, after the shutdown for maintenance, when the first roll of special steel is about to enter the insulation corridor, the heating device is started. The intelligent control system automatically calculates and adjusts the power of the heating device according to the initial temperature and ambient temperature in the insulation corridor. For example, when the initial temperature in the insulation corridor is 20°C and the ambient temperature is 10°C, the intelligent control system adjusts the power of the heating device to 15kW, so that the internal temperature of the insulation corridor is quickly raised to 30°C within 15-20 minutes and remains stable.

[0117] During normal production, the temperature is monitored in real time by the temperature sensor installed inside the insulation corridor. When the temperature exceeds 35°C, the intelligent control system issues a command to open the electric sunroof 4 and the swing window 3 at the same time. According to the temperature increase, the intelligent control system automatically adjusts the opening angles of the electric sunroof and the swing window. For example, when the temperature rises to 38°C, the opening angle of the electric sunroof is adjusted to 60°, and the opening angle of the swing window is adjusted to 45°, so that the air forms a good convection and achieves natural cooling. When the temperature drops to 32°C, the intelligent control system gradually reduces the opening angles of the electric sunroof and the swing window until the temperature stabilizes in the range of 30-40°C.

Claims

1. A PF line insulation corridor device, characterized in that: include: Insulated corridor side walls (1), an insulated corridor roof (2), a swing window (3), an electric skylight (4), a sliding door (5) and a heating device; The insulation corridor side wall (1) is a rectangular box frame welded from steel plates with a thickness of 3-5 mm, and a double-layer rock wool insulation board is tightly stuffed into the rectangular box frame, and each layer of rock wool insulation board is 50-80 mm thick; The insulation corridor top cover (2) is welded from a steel plate with a thickness of 3-5 mm to form a special-shaped box frame, and a double-layer rock wool insulation board is tightly stuffed into the special-shaped box frame, and each layer of rock wool insulation board is 50-80 mm thick. The insulation corridor side wall (1) and the insulation corridor top cover (2) together form an insulation corridor; The swing windows (3) are evenly installed at the lower end of the side wall (1) of the heat preservation corridor. Each swing window (3) is composed of a rectangular box frame welded from steel plates with a thickness of 2-3 mm. 3-5 welded hinges are welded above the swing window (3). The hinges are fixed to the upper frame. A windproof hook is arranged above the swing window (3) and a spring latch is arranged below. The electric skylights (4) are evenly arranged on the top cover (2) of the thermal insulation corridor; The sliding door (5) is arranged on one side of the side wall (1) of the heat-insulating corridor, and is welded into a frame by profiles and steel plates with a thickness of 3-5 mm, and a sealing strip is installed on the edge of the sliding door (5); The heating device is installed in the inner space of the insulation corridor, adopts electromagnetic heating or infrared heating technology, has a power of 10-20kW, and is equipped with a temperature sensor with an accuracy of ±0.5°C.

2. A PF line insulation corridor device according to claim 1, characterized in that: The length of the welded hinge is 80-100mm and the width is 30-40mm; the windproof hook is made of stainless steel and has a length of 50-70mm; the insertion depth of the spring latch is 15-20mm.

3. A PF line insulation corridor device according to claim 1, characterized in that: The sliding door (5) has a height of 2-2.5 m and a width of 1-1.5 m.

4. The PF line insulation corridor device according to claim 1, characterized in that: The electric skylight (4) comprises: a welded box frame (401), a roller (402), a guide groove (403) and an electric push rod (404); the welded box frame (401) is installed in the interior of the heat-insulating corridor, which is enclosed by the side wall (1) of the heat-insulating corridor and the top cover (2) of the heat-insulating corridor; the roller (402) is installed on the welded box frame (401); the guide groove (403) is arranged in the interior of the heat-insulating corridor, which is enclosed by the side wall (1) of the heat-insulating corridor and the top cover (2) of the heat-insulating corridor; the roller (402) rolls in the guide groove (403); the electric push rod (404) is connected to the welded box frame (401) and provides power for opening and closing the frame; the swing window (3) in the open state and the electric skylight (4) in the open state form a convection channel.

5. The PF line insulation corridor device according to claim 4, characterized in that: The roller (402) has a diameter of 80-100 mm and is made of high-strength polyurethane; the guide groove (403) has a length of 1-2 m and a precision controlled within ±0.5 mm; the electric push rod (404) has a thrust of 500-1000 N and a stroke of 300-500 mm.

6. A cooling control method for a PF line insulation corridor, characterized in that: include: Heating and insulation after shutdown and maintenance, temperature control during normal production, intelligent adjustment under different production processes and emergency handling of abnormal situations.

7. A cooling control method for a PF line insulation corridor according to claim 6, characterized in that: The heating and insulation after shutdown and maintenance include: after shutdown and maintenance, 30 minutes before the first roll of special steel enters the insulation corridor, the heating device starts preheating; the intelligent control system collects data from temperature sensors at 5 different positions in the insulation corridor in real time, takes the average value as the initial temperature T0, and obtains the external environment temperature Te at the same time; According to the heat loss model of the insulation corridor pre-entered into the system, the intelligent control system calculates the heat Q required to heat the corridor to the target temperature; the formula is: $Q=mc(T-T0)+kA(T-Te)t$, where m is the mass of the air in the corridor, c is the specific heat capacity of the air, T is the target temperature of 35°C, k is the total heat transfer coefficient of the insulation material, A is the total surface area of ​​the corridor, and t is the expected heating time of 20 minutes; According to the heat Q and the thermal efficiency η of the heating device, the power P that the heating device needs to output is calculated: $P=\frac{Q}{\etat}$; the system automatically adjusts the power of the heating device accordingly, so that the temperature inside the insulation corridor rises to 35°C at a uniform rate within 20 minutes; during the heating process, the temperature sensor collects data every 2 minutes, and the intelligent control system fine-tunes the heating power in real time according to the deviation between the actual heating curve and the preset curve to ensure the stability of the heating process; After reaching the target temperature, the temperature sensor continuously monitors the temperature in a 1-minute cycle; if the temperature fluctuation exceeds ±1°C, the intelligent control system adjusts the power of the heating device according to the PID control algorithm based on the positive and negative and size of the temperature deviation.

8. The cooling control method for the PF line insulation corridor according to claim 6 is characterized by: Temperature control during normal production includes: During normal production, five temperature sensors evenly distributed in the insulation corridor monitor the temperature in real time with a cycle of 30 seconds. When any of the sensors detects that the temperature exceeds 35°C, the intelligent control system immediately starts the cooling program. The system first calculates the average temperature Tavg and the temperature standard deviation σ in the corridor based on data from multiple temperature sensors; if Tavg is between 35-37°C and σ<2°C, it indicates that the temperature rise is relatively uniform, and the intelligent control system controls the electric sunroof to open to 30° and the swing window to open to 20°; if Tavg is between 37-38°C and σ<3°C, the electric sunroof opens to 45° and the swing window opens to 30°; if Tavg ≥38°C or σ≥3°C, the electric sunroof and swing window are fully opened; During the ventilation and cooling process, the temperature sensor continuously feeds back data; the intelligent control system recalculates Tavg and σ based on the new temperature data in a 1-minute cycle, and adjusts the opening angles of the electric sunroof and swing window according to the fuzzy control algorithm; When the temperature drops to 32℃, the intelligent control system begins to gradually reduce the opening angles of the electric sunroof and swing window; first reduce the opening angles of the electric sunroof and swing window by 10° at the same time, and observe the temperature changes within 5 minutes. If the temperature is stable or rises slightly and remains between 30-32℃, maintain the current opening angle; if the temperature continues to drop, continue to reduce the opening angle by 5° each time until the temperature stabilizes within the range of 30-40℃.

9. The cooling control method for the PF line insulation corridor according to claim 6 is characterized by: Intelligent adjustments under different production processes include: The system pre-stores a variety of cooling curve templates for different special steel production processes; before production, the operator selects the corresponding cooling curve template according to the type of special steel actually produced, and the intelligent control system adjusts the temperature control strategy according to the selected template; The intelligent control system dynamically adjusts the ventilation strategy according to the conveying speed of the coils on the production line; when the coil conveying speed increases, the opening angle of the ventilation equipment is increased according to the speed increase ratio; when the conveying speed slows down, the opening angle is reduced according to the speed reduction ratio to ensure that each coil can be accurately cooled.

10. The cooling control method for the PF line insulation corridor according to claim 6, characterized in that: Emergency response to abnormal situations includes: During the entire cooling control process, the intelligent control system monitors the equipment status and temperature data in real time; if the data collected by a temperature sensor fluctuates abnormally for three consecutive times or deviates from the data of other sensors by more than ±3°C, the system immediately starts the backup temperature sensor and sends the number and fault information of the faulty sensor to the operator's terminal device, notifying the maintenance personnel to carry out maintenance; If the current of the electric push rod exceeds 120% of the rated current when the electric skylight or swing window is opening or closing, the intelligent control system will first try to send 3 different control instructions. If the problem is still not solved, the system will immediately shut down the equipment and start the backup ventilation equipment. At the same time, the system will adjust the power of the heating device according to the current temperature and the remaining cooling time to maintain the temperature in the insulation corridor within the allowable fluctuation range.

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