Production method for heating section steel blank by adopting heat accumulating type heating furnace

Abstract

The invention discloses a production method for heating a section steel blank by adopting a regenerative heating furnace, which comprises the following steps: in a regenerative combustion mode, burners on two sides of a heat supply section form a corresponding relationship, and when an air gas valve on the right side is closed and a smoke valve is opened, and an air gas valve on the left side is opened and the smoke valve is closed, the burner is closed; air and fuel gas are preheated through the heat accumulator on the left side and enter the furnace to be combusted; waste gas is discharged from the heat accumulator on the right side, and meanwhile the heat accumulator on the right side is preheated to a proper temperature; after set time, left-right reversing is conducted, air and fuel gas are preheated through the heat accumulator on the right side and enter the furnace to be combusted, waste gas is exhausted from the heat accumulator on the left side, and meanwhile the heat accumulator on the left side is preheated to the proper temperature; afterwards, the previous process is repeated. The problems that a heating furnace is insufficient in heat storage capacity and high in furnace pressure are solved through existing heating equipment, the high-quality steel rail blank is finally obtained, and a solid early-stage foundation is laid for follow-up rolling of the high-quality steel rail.

Description

Technical Field

[0001] The invention belongs to the technical field of metallurgical materials, and in particular relates to a production method for heating a steel blank by using a regenerative heating furnace. Background Art

[0002] In the late 1980s, the regenerative heating technology was introduced to China from Japan. Through the application of regenerative heating technology, low calorific value blast furnace and converter gas can be effectively utilized to heat steel billets through ladle baking in converter workshop and steel rolling heating furnace. The technical advantages of energy saving and environmental protection quickly attracted the attention of many domestic steel enterprises and metallurgical industry design and research departments. In the early 1990s, the regenerative waste heat recovery technology has been rapidly developed; many improvements have been made in the material, structure, and heat storage performance of the regenerative body. At present, the application and promotion of regenerative heating furnaces have become the main energy-saving measures and development direction of steel rolling enterprises. However, due to the short development and utilization time of domestic regenerative heating technology, the process technology of some related parts is not yet very mature, which makes many regenerative furnaces that have been put into use have some inherent process defects, and the actual application effect of regenerative heating furnaces varies greatly.

[0003] Baosteel Rail Beam Factory keeps pace with the times and introduces a regenerative heating furnace to heat the rail blanks in accordance with its own production conditions. Some serious process and technical problems also occurred during the early operation. Through a series of advanced process optimization and technical improvement measures, the regenerative heating furnace has been transformed, and many improvements have been made in the material, structure, and heat storage performance of the regenerative body. The heat transfer area per unit volume has been raised from 10-40m2 / m3 to 200-1300m2 / m3, so the volume has been significantly reduced; the structure of the reversing valve and the reliability of the control system have also been improved, and the reversing cycle has been shortened from about 30 minutes to a few minutes or tens of seconds, and the thermal efficiency has been greatly improved to about 70%-90%, and the preheating temperature of the combustion air or fuel has been greatly increased to more than 1000℃, while the exhaust flue gas temperature can be reduced to below 200℃, close to the dew point temperature of the flue gas. As the preheating temperature of the combustion air is as high as 1000℃, which is much higher than the traditional 500-600℃, the traditional fuel combustion method has been changed, and a new combustion technology - high temperature air combustion (HTAC) technology has emerged. The key to this technology is that it can realize the low-temperature and low-oxygen combustion process through efficient thermal storage waste heat recovery, forming a flame characteristic that is very different from traditional combustion, thereby achieving the dual benefits of energy saving and environmental protection. At present, the thermal storage heating furnaces are in good operating condition and have achieved considerable economic benefits. Summary of the invention

[0004] The purpose of the present invention is to provide a production method for heating steel billets using a heat storage heating furnace, using the current heating equipment to improve the problems of insufficient heat storage capacity and high furnace pressure of the heating furnace, and ultimately obtaining high-quality rail billets, laying a solid preliminary foundation for the subsequent rolling of high-quality rails.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] The present invention discloses a production method for heating steel billets by using a regenerative heating furnace. Most of the steel billets are 280*380mm billets for heating and rolling. Air and gas dual regenerative combustion control is used in the heating process. Multiple pairs of regenerative burners are symmetrically arranged on both sides of the furnace. The burners on both sides are periodically reversed to complete the switching process of "heat storage-air supply" and "heat storage-gas supply".

[0007] In the heat storage combustion mode, the burners on both sides of the heating section form a corresponding relationship. When the air gas valve on the right is closed, the smoke valve is opened, the air gas valve on the left is opened, and the smoke valve is closed, the air and gas are preheated through the heat storage body on the left and enter the furnace for combustion; the exhaust gas is discharged from the heat storage body on the right, and the heat storage body on the right is preheated to an appropriate temperature; after a set time, the left and right directions are reversed, the air and gas are preheated through the heat storage body on the right and enter the furnace for combustion, the exhaust gas is discharged from the heat storage body on the left, and the heat storage body on the left is preheated to an appropriate temperature; after that, the previous process is repeated.

[0008] Furthermore, during the reversing process, a nitrogen backflush system is provided to blow as much residual gas in the pipe in front of the burner as possible into the furnace for combustion when switching from gas supply to smoke exhaust, thereby reducing gas reversing losses and saving energy.

[0009] Furthermore, under normal circumstances, the reversing device adopts a periodic reversing method; the switching cycle time is issued by the PLC and the reversing is automatic; the reversing cycle can be adjusted on the HMI according to actual conditions; at the same time, the system is provided with a manual reversing operation mode; when switched to this mode, the reversing valve is manually operated through the HMI.

[0010] Furthermore, under normal production conditions, the furnace pressure must be kept at a slightly positive pressure, satisfying ≤30Pa.

[0011] Furthermore, attention should be paid to the low-pressure signal of the gas. When the burner is turned on, the nitrogen and gas low-pressure should be locked in the microcomputer. The dispatch room should be contacted in time when the gas pressure is low. When the gas pressure is lower than 2500Pa, the gas should be reduced and kept warm. When the gas pressure is lower than 2000Pa, the furnace should be stopped. When the gas pressure returns to normal above 3500Pa, the furnace can be started.

[0012] When there is a sudden power outage, the valve position of each section of the gas pipe valve should be closed on the microcomputer and should be greater than 10%. At the same time, the flue gas temperature before the air preheater must be strictly controlled, and the maximum temperature is not allowed to exceed 800℃ to avoid burning the air preheater. If the air preheating temperature is too high and greater than 500℃, cold air and hot air should be mixed and released. During production, the furnace loading and unloading doors should be tightly closed to prevent cold air from entering the furnace, increasing iron oxide scale, or the flame in the furnace from entering the furnace door and burning the furnace door frame.

[0013] Furthermore, a heat storage walking beam heating furnace is used in the heating process, with a furnace bottom strength of 564kg / ㎡.h, a billet outlet temperature of MAX=1250℃, and - is used to improve the problem of insufficient heat storage capacity of the heating storage furnace.

[0014] Furthermore, the specific parameters of the regenerative heating furnace are set as follows:

[0015] 1). Furnace type: regenerative walking beam heating furnace;

[0016] 2). Support beams: There are five fixed beams and four movable beams in the furnace;

[0017] 3). Driving mode of stepping machinery - full hydraulic drive;

[0018] 4). Material feeding and discharging method: using loading and discharging machine, end feeding and end discharging;

[0019] 5). The effective length is 36500mm, the inner width is 14600mm, the bricklaying length is 38900mm, and the bricklaying width is 15640mm;

[0020] 6). Furnace bottom strength: 564kg / ㎡.h;

[0021] 7). Billet out-of-furnace temperature: MAX = 1250°C;

[0022] 8). Furnace heating capacity: 280t / h cold billet;

[0023] 9). Fuel type: high-pressure and coke oven mixed gas;

[0024] 10). Fuel calorific value: 7524KJ / Nm 3 ;

[0025] 11). Rated gas consumption: 52475Nm 3 / h;

[0026] 12). Rated air consumption: 97079Nm 3 / h;

[0027] 13). Rated smoke volume: 139584Nm 3 / h;

[0028] 14). Burner: 80 sets of air-gas regenerative burners, 4 sub-high-speed burners, 11 ignition burners;

[0029] 15). Heating capacity configuration:

[0030] Soaking section: 10 upper M950 gas regenerative burners;

[0031] 10 M1180 air regenerative burners at the bottom;

[0032] Heating stage: 16 upper M1180 gas regenerative burners;

[0033] 16 M1450 air regenerative burners at the bottom;

[0034] Heating stage 2: 14 upper M1180 gas regenerative burners;

[0035] 14 M1450 air regenerative burners at the bottom;

[0036] Preheating section: 2 upper sub-high speed burners;

[0037] Two lower sub-high speed burners;

[0038] Each section is equipped with ignition burners: 11 low-pressure vortex burners DW-Ι-9;

[0039] The fuel distribution ratio between the upper and lower parts is: 47% in the upper part and 53% in the lower part;

[0040] The fuel distribution ratio of each section is: 10% for preheating section, 35% for heating section 1, 35% for heating section 2, and 20% for equalizing section;

[0041] Gas pressure before burner: 3000Pa;

[0042] Air pressure before burner: 4000Pa;

[0043] 16). Stepper mechanical type: double-layer frame slope double roller type

[0044] 17). Walking beam travel: lifting travel: 200mm, 100mm up and down, translation travel: 0~500mm adjustable, stepping cycle: 60s;

[0045] 18). Fabric laying method: 5.8m~9.2m staggered fabric laying, 9.5~13.6m single-row fabric laying;

[0046] 19). Stepper mechanical function:

[0047] Positive cycle—the billet moves forward;

[0048] Reverse cycle - billet retreats;

[0049] Stepping - the billet only moves up and down;

[0050] Intermediate holding - the movable beam and the fixed beam support the billet at the same time;

[0051] Stepping waiting - the stepping cycle runs according to the steel-making cycle

[0052] 20). Stepping mechanical type: double-layer frame slope double roller type;

[0053] 21). Translation hydraulic cylinder: 2;

[0054] 22). Lifting hydraulic cylinder: 2;

[0055] 23). Blower: Quantity: 2 units, Model: 9-26-21F left 45°, Power: 560KW, Flow: 130000m 3 / s, total pressure: ≥10000Pa;

[0056] Main engine speed: 995r / min Medium temperature: normal temperature, rated current: 41.2A;

[0057] 27). Induced draft fan

[0058] Quantity: 4 units, model: 9-26-20.5F left 45°, power: 400KW flow: 135000M 3 / h, total pressure: ≥5600Pa;

[0059] 28). Technical parameters of smoke exhaust system chimney

[0060] The empty smoke chimney is 40m and the outlet diameter is 2.32m;

[0061] The coal smoke chimney is 40m and the outlet diameter is 1.4m;

[0062] 29). Water cooling system: Cooling water consumption: 120t / h; Cooling water pressure ≥0.4Mpa.

[0063] Compared with the prior art, the beneficial technical effects of the present invention are:

[0064] The present invention utilizes the existing heating equipment to improve the problems of insufficient heat storage capacity and high furnace pressure of the heating furnace, and finally obtains high-quality rail blanks, laying a solid preliminary foundation for the subsequent rolling of high-quality rails. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] The present invention will be further described below in conjunction with the accompanying drawings.

[0066] Figure 1 Thermal engineering system for steel sections. DETAILED DESCRIPTION

[0067] Most of the steel billets are heated and rolled with 280*380mm billets, and air-gas dual regenerative combustion control is used during the heating process. On both sides of the furnace, multiple pairs of regenerative burners are symmetrically arranged, and the burners on both sides are periodically reversed to complete the switching process of "regenerative-air supply" and "regenerative-gas supply".

[0068] In the heat storage combustion mode, the burners on both sides of the heating section form a corresponding relationship. When the air gas valve on the right is closed, the smoke valve is opened, the air gas valve on the left is opened, and the smoke valve is closed, the air and gas are preheated through the heat storage body on the left and enter the furnace for combustion. The exhaust gas is discharged from the heat storage body on the right, and the heat storage body on the right is preheated to an appropriate temperature. After a set time, the left and right directions are reversed, and the air and gas are preheated through the heat storage body on the right and enter the furnace for combustion. The exhaust gas is discharged from the heat storage body on the left, and the heat storage body on the left is preheated to an appropriate temperature. After that, the previous process is repeated. Based on the working principle of the heat storage combustion system, the present invention improves the working efficiency of the heating furnace by adjusting the heating configuration of the burner and other methods. The specific process is as follows:

[0069] 1. Furnace type: regenerative walking beam heating furnace

[0070] 2. Support beams: There are five fixed beams and four movable beams in the furnace.

[0071] 3. The driving mode of stepping machinery - full hydraulic drive.

[0072] 4. Material feeding and discharging method: using loading and discharging machine, end-in and end-out.

[0073] 5. The effective length is 36500mm, the inner width is 14600mm, the bricklaying length is 38900mm, and the bricklaying width is 15640mm.

[0074] 6. Furnace bottom strength: 564kg / ㎡.h

[0075] 7. Billet out of furnace temperature: MAX = 1250℃

[0076] 8. Furnace heating capacity: 280t / h (cold billet)

[0077] 9. Fuel type: High-pressure and coke oven mixed gas

[0078] 10. Fuel calorific value: 7524KJ / Nm 3

[0079] 11. Rated gas consumption: 52475Nm 3 / h

[0080] 12. Rated air consumption: 97079Nm 3 / h

[0081] 13. Rated smoke volume: 139584Nm 3 / h

[0082] 14. Burner: 80 sets of air-gas regenerative burners, 4 sub-high-speed burners, 11 ignition burners

[0083] 15. Heating capacity configuration:

[0084] Soaking section: 10 upper M950 gas regenerative burners

[0085] 10 lower M1180 air regenerative burners

[0086] Heating stage: 16 upper M1180 gas regenerative burners

[0087] 16 lower M1450 air regenerative burners

[0088] Heating stage 2: 14 upper M1180 gas regenerative burners

[0089] 14 lower M1450 air regenerative burners

[0090] Preheating section: 2 upper sub-high speed burners

[0091] 2 lower sub-high speed burners

[0092] Each section is equipped with ignition burners: low-pressure vortex burners DW-Ι-9 11 pcs

[0093] The fuel distribution ratio between the upper and lower parts is: 47% in the upper part and 53% in the lower part

[0094] The fuel distribution ratio of each section is: preheating section 10%, heating section 1 35%, heating section 2 35%, equalizing section 20% Gas pressure before burner: 3000Pa

[0095] Air pressure before burner: 4000Pa

[0096] 16. Stepper machine type: double-layer frame slope double roller type

[0097] 17. Stepping beam travel: lifting travel: 200mm (up and down 100mm each), translation travel: 0~500mm adjustable, stepping cycle: 60S

[0098] 18. Fabric feeding method: 5.8m~9.2m staggered fabric feeding, 9.5~13.6m single-row fabric feeding

[0099] 19. Stepper mechanical function:

[0100] Positive cycle - billet moving forward

[0101] Reverse cycle - billet retreat

[0102] Stepping - the billet only moves up and down

[0103] Intermediate holding - movable beam and fixed beam support the billet at the same time

[0104] Stepping waiting - the stepping cycle runs according to the steel-making cycle

[0105] 20. Stepper machine type: double-layer frame slope double roller type

[0106] 21. Translation hydraulic cylinder: 2

[0107] 22. Lifting hydraulic cylinder: 2

[0108] 23. Blower: Quantity: 2 units, Model: 9-26-21F left 45°, Power: 560KW, Flow: 130000m 3 / s, total pressure: ≥10000Pa

[0109] Main engine speed: 995r / min Medium temperature: normal temperature Rated current: 41.2A

[0110] 27. Draft fan

[0111] Quantity: 4 units, model: 9-26-20.5F left 45°, power: 400KW flow: 135000M 3 / h, total pressure: ≥5600Pa

[0112] 28. Technical parameters of smoke exhaust system chimney

[0113] Empty smoke chimney 40m outlet diameter 2.32m

[0114] Smoke chimney 40m outlet diameter 1.4m

[0115] 29. Water cooling system: Cooling water consumption: 120t / h (forced circulation evaporation cooling, pure circulating water cooling. Cooling water pressure ≥ 0.4Mpa.

[0116] During the reversing process, a nitrogen backflush system is provided. When switching from gas supply to smoke exhaust, as much residual gas in the pipe in front of the burner as possible is blown into the furnace for combustion, reducing gas reversing losses and saving energy. Under normal circumstances, the reversing device adopts a periodic reversing mode. The switching cycle time is issued by the PLC and automatically reverses. The reversing cycle can be adjusted on the HMI according to actual conditions. At the same time, the system is equipped with a manual reversing operation mode. When switched to this mode, the reversing valve is manually operated through the HMI.

[0117] At the same time, check the furnace pressure fluctuation and adjust the flue damper in time. Under normal production conditions, ensure that the furnace pressure is at a slightly positive pressure (≤30Pa). At the same time, pay attention to the low-pressure signal of the gas. When the burner is turned on, the nitrogen and gas low pressure should be locked in the microcomputer. The low gas pressure should be contacted with the dispatching room in time. When the gas pressure is lower than 2500Pa, the gas pressure should be reduced and kept warm.

[0118] When the gas pressure is lower than 2000Pa, the furnace needs to be stopped. When the gas pressure returns to normal (above 3500Pa), the furnace can be started. When there is a sudden power outage, the valve position of each section of the gas pipe valve should be closed on the microcomputer (but more than 10%). At the same time, the flue gas temperature before the air preheater must be strictly controlled. The maximum temperature is not allowed to exceed 800℃ to avoid burning the air preheater. When the air preheating temperature is too high (greater than 500℃), cold air and hot air should be mixed and released. During production, the furnace loading and unloading door should be tightly closed to prevent cold air from entering the furnace to increase iron oxide scale or the flame in the furnace from entering the furnace door and burning the furnace door frame.

[0119] Heating configuration: The heating furnace uses air and gas double heat storage burners for heating, which are divided into 6 combustion control sections: heating section 1, heating section 2, heating section 3 upper, heating section 3 lower, soaking section upper, soaking section lower. Each control section adopts segmented and side reversing. Whether one of the heating sections is enabled or not can be determined according to the output of the heating furnace.

[0120] Table 1 Burners and heating configuration of each section of heating furnace

[0121]

[0122] In order to reduce oxidation and burning loss, improve furnace temperature uniformity and heating quality, and reduce gas consumption, a double regenerative burner is used, which consists of air regenerative box, gas regenerative box, burner bricks and other parts. The specific configuration of the burner in each section of the heating furnace is shown in Table 1. The burner nozzle adopts a porous structure, and the optimal nozzle flow rate and nozzle angle will be designed according to the furnace width and gas characteristics, so that air and gas form the best state of diffuse combustion in the furnace, reduce NOx and CO emissions, and save energy. The burner bricks are prefabricated in the manufacturer to ensure the accuracy of the burner nozzle and angle.

[0123] The reversing cycle of the regenerative burner is 40 to 60 seconds, with time and exhaust gas temperature as control parameters. During normal operation, the reversing cycle is within 60 seconds. Extending the cycle time as much as possible can reduce the number of reversing times, reduce gas reversing losses, and save energy.

[0124] Experimental comparison before and after heating furnace process adjustment

[0125]

[0126] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A production method for heating steel blanks using a regenerative heating furnace, characterized in that: Most of the steel billets are heated and rolled with 280*380mm billets. During the heating process, air-gas dual regenerative combustion control is adopted. On both sides of the furnace, multiple pairs of regenerative burners are symmetrically arranged. The burners on both sides are periodically reversed to complete the switching process of "regenerative-air supply" and "regenerative-gas supply". In the heat storage combustion mode, the burners on both sides of the heating section form a corresponding relationship. When the air gas valve on the right is closed, the smoke valve is opened, the air gas valve on the left is opened, and the smoke valve is closed, the air and gas are preheated through the heat storage body on the left and enter the furnace for combustion; the exhaust gas is discharged from the heat storage body on the right, and the heat storage body on the right is preheated to an appropriate temperature; after a set time, the left and right directions are reversed, the air and gas are preheated through the heat storage body on the right and enter the furnace for combustion, the exhaust gas is discharged from the heat storage body on the left, and the heat storage body on the left is preheated to an appropriate temperature; after that, the previous process is repeated.

2. The method for producing steel blanks by using a regenerative heating furnace according to claim 1, characterized in that: During the reversing process, a nitrogen backflush system is provided to blow as much residual gas in the pipe in front of the burner as possible into the furnace for combustion when switching from gas supply to smoke exhaust, thereby reducing gas reversing losses and saving energy.

3. The method for producing steel blanks by using a regenerative heating furnace according to claim 2, characterized in that: Under normal circumstances, the reversing device adopts a periodic reversing method; the switching cycle time is issued by the PLC and the reversing is automatic; the reversing cycle can be adjusted on the HMI according to actual conditions; at the same time, the system is equipped with a manual reversing operation mode; when switched to this mode, the reversing valve is manually operated through the HMI.

4. The method for producing steel blanks by using a regenerative heating furnace according to claim 1, characterized in that: Under normal production conditions, the furnace pressure must be kept at a slightly positive pressure, meeting the requirement of ≤30Pa.

5. The method for producing steel blanks by using a regenerative heating furnace according to claim 1, characterized in that: At the same time, pay attention to the low-pressure signal of gas. When the burner is turned on, the microcomputer should lock the nitrogen and gas low-pressure interlocking. When the gas pressure is low, contact the dispatch room in time. When the gas pressure is lower than 2500Pa, reduce the amount of heat preservation. When the gas pressure is lower than 2000Pa, stop the furnace. Wait until the gas pressure returns to normal above 3500Pa, start the furnace. When there is a sudden power outage, the valve position of each section of the gas pipe valve should be closed on the microcomputer and should be greater than 10%. At the same time, the flue gas temperature before the air preheater must be strictly controlled, and the maximum temperature is not allowed to exceed 800℃ to avoid burning the air preheater. If the air preheating temperature is too high and greater than 500℃, cold air and hot air should be mixed and released. During production, the furnace loading and unloading doors should be tightly closed to prevent cold air from entering the furnace, increasing iron oxide scale, or the flame in the furnace from entering the furnace door and burning the furnace door frame.

6. The method for producing steel blanks by using a regenerative heating furnace according to claim 1, characterized in that: The specific parameters of the regenerative heating furnace are set as follows: 1). Furnace type: regenerative walking beam heating furnace; 2). Support beams: There are five fixed beams and four movable beams in the furnace; 3). Driving mode of stepping machinery - full hydraulic drive; 4). Material feeding and discharging method: using loading and discharging machine, end feeding and end discharging; 5). The effective length is 36500mm, the inner width is 14600mm, the bricklaying length is 38900mm, and the bricklaying width is 15640mm; 6). Furnace bottom strength: 564kg / ㎡.h; 7). Billet out-of-furnace temperature: MAX = 1250°C; 8). Furnace heating capacity: 280t / h cold billet; 9). Fuel type: high-pressure and coke oven mixed gas; 10). Fuel calorific value: 7524KJ / Nm 3 ; 11). Rated gas consumption: 52475Nm 3 / h; 12). Rated air consumption: 97079Nm 3 / h; 13). Rated smoke volume: 139584Nm 3 / h; 14). Burner: 80 sets of air-gas regenerative burners, 4 sub-high-speed burners, 11 ignition burners; 15). Heating capacity configuration: Soaking section: 10 upper M950 gas regenerative burners; 10 M1180 air regenerative burners at the bottom; Heating stage: 16 upper M1180 gas regenerative burners; 16 M1450 air regenerative burners at the bottom; Heating stage 2: 14 upper M1180 gas regenerative burners; 14 M1450 air regenerative burners at the bottom; Preheating section: 2 upper sub-high speed burners; Two lower sub-high speed burners; Each section is equipped with ignition burners: 11 low-pressure vortex burners DW-Ι-9; The fuel distribution ratio between the upper and lower parts is: 47% in the upper part and 53% in the lower part; The fuel distribution ratio of each section is: 10% for preheating section, 35% for heating section 1, 35% for heating section 2, and 20% for equalizing section; Gas pressure before burner: 3000Pa; Air pressure before burner: 4000Pa; 16). Stepper mechanical type: double-layer frame slope double roller type 17). Walking beam travel: lifting travel: 200mm, 100mm up and down, translation travel: 0~500mm adjustable, stepping cycle: 60s; 18). Fabric laying method: 5.8m~9.2m staggered fabric laying, 9.5~13.6m single-row fabric laying; 19). Stepper mechanical function: Positive cycle—the billet moves forward; Reverse cycle - billet retreats; Stepping - the billet only moves up and down; Intermediate holding - the movable beam and the fixed beam support the billet at the same time; Stepping waiting - the stepping cycle runs according to the steel-making cycle 20). Stepping mechanical type: double-layer frame slope double roller type; 21). Translation hydraulic cylinder: 2; 22). Lifting hydraulic cylinder: 2; 23). Blower: Quantity: 2 units, Model: 9-26-21F left 45°, Power: 560KW, Flow: 130000m 3 / s, total pressure: ≥10000Pa; Main engine speed: 995r / min Medium temperature: normal temperature, rated current: 41.2A; 27). Induced draft fan Quantity: 4 units, model: 9-26-20.5F left 45°, power: 400KW flow: 135000M 3 / h, total pressure: ≥5600Pa; 28). Technical parameters of smoke exhaust system chimney The diameter of the outlet of the 40m empty smoke chimney is 2.32m; The outlet diameter of the coal smoke chimney is 40m and 1.4m; 29). Water cooling system: Cooling water consumption: 120t / h; Cooling water pressure ≥0.4Mpa.

Images