A method and device for producing wear-resistant steel by online heat treatment process

Abstract

The present invention discloses a device and method for producing wear-resistant steel by an online heat treatment process. The method for producing wear-resistant steel includes the following steps: continuous casting billet preparation, slow cooling of steel billets, heating of steel billets, rough rolling, finishing rolling, online quenching, online tempering and finishing; in the online tempering process, UFC cooling equipment is used for online quenching, and an edge blowing and suction device is used to absorb moisture from the edge of the steel plate. The wear-resistant steel production process of the present invention avoids the process of cooling and then heating before the existing heat treatment process by performing online quenching, online tempering and finishing after rolling, effectively reduces the energy consumption of wear-resistant steel production, and reduces the tendency of quenching cracking; the steel plate raw material adopts a design without adding V components, which effectively reduces the cost of wear-resistant steel, and can improve the welding performance and low-temperature toughness of NM400; an edge blowing and suction device is used to absorb moisture from the edge of the steel plate, reduce the residual moisture at the edge of the steel plate, make the steel plate cool evenly, and improve the production quality of the steel plate.

Description

Technical Field

[0001] The invention relates to the technical field of wear-resistant steel, in particular to a method and a device for producing wear-resistant steel by online heat treatment process. Background Art

[0002] At present, the production of wear-resistant steel mainly adopts the process route of molten iron-converter-refining-continuous casting-heating furnace-rolling-finishing-quenching-tempering. This process route requires the wear-resistant steel to be cooled to below 150°C after rolling before finishing, otherwise the mechanical shear fracture will appear blue and brittle; this results in a cooling and then heating process before the wear-resistant steel is heat treated, and quenching and tempering are sometimes not carried out continuously, resulting in internal stress cracking of the wear-resistant steel.

[0003] The use of online quenching-online tempering process can avoid the process of cooling down and then heating up the steel plate before heat treatment in the finishing-quenching-tempering process route, effectively reducing the energy consumption of wear-resistant steel production and reducing the tendency of quenching cracking.

[0004] The patent with application number 202110039833.9 discloses an online quenching method for medium and thick plates, comprising dephosphorizing, primary rolling and finish rolling the continuously cast slab to obtain a finished plate; the finished plate comprises a first medium and thick plate with a thickness of ≤50 mm and a length of 8 to 30 m: a second medium and thick plate with a thickness of 50 to 90 mm and a length of 8 to 20 m; the finished plate is cooled in two stages to obtain a quenched plate; in the two-stage cooling, the first medium and thick plate adopts straight-through cooling; the second medium and thick plate adopts swing cooling, and the two-stage cooling includes: the first stage cooling is cooling under the ADCOS-PM inclined jet cooling device; the second stage cooling is cooling under the ACC laminar cooling device.

[0005] During online quenching, the edge of the steel plate is not only cooled by the direct spray of water from the nozzle, but also by the secondary cooling caused by the water on the surface of the steel plate flowing to both sides. Therefore, the temperature drop at the edge is large, resulting in uneven cooling of the steel plate and affecting the quality of the steel plate. Summary of the invention

[0006] The purpose of the present invention is to solve the above problems and to design a method and device for producing wear-resistant steel by online heat treatment process.

[0007] To achieve the above-mentioned purpose, the technical solution of the present invention is a device and method for producing wear-resistant steel by online heat treatment process. The method for producing wear-resistant steel comprises the following steps:

[0008] S1. Preparation of continuous casting billet; the chemical composition mass percentage of the continuous casting billet is C=0.20%~0.28%, Si=0.20~0.40, Mn=1.45~1.55, P≤0.015, S≤0.005, Als=0.015~0.030, Nb=0.020~0.030, Ti=0.020~0.030, B=0.002~0.005, and the balance is Fe and unavoidable impurities; prepare the raw materials according to the above composition, and go through hot metal desulfurization, converter smelting, refining, RH vacuum The continuous casting billet with the above composition and mass percentage is obtained by air refining and continuous casting process; the continuous casting billets with three thickness specifications of 180mm, 250mm and 320mm are used, and the 180mm continuous casting billet is rolled into a steel plate with a thickness of 12-25mm, the 250mm continuous casting billet is rolled into a steel plate with a thickness of 25-35mm, and the 320mm continuous casting billet is rolled into a steel plate with a thickness of 35-40mm; the design without adding V component can effectively reduce the cost of wear-resistant steel, and at the same time can improve the welding performance and low-temperature toughness of NM400 wear-resistant steel;

[0009] S2, slow cooling of the steel billet: the steel billet is slowly cooled in the slow cooling pit, and then put into the furnace for heating after 24 hours of slow cooling;

[0010] S3. Billet heating: furnace temperature ≤ 500℃, heating process should ensure full solid solution of niobium alloy and fine and uniform original austenite grains, heating section temperature controlled at 1250±20℃, soaking temperature controlled at 1210±20℃, heating time controlled at 8~10min / cm, soaking time controlled at 40-60min, furnace exit temperature controlled at 1100±20℃;

[0011] S4, rough rolling;

[0012] S5, finishing rolling;

[0013] S6, online quenching; use UFC cooling equipment for online quenching, use edge blowing and suction device to absorb moisture from the edge of the steel plate, control the cooling temperature after rolling within the range of 830-860℃, and control the red-return temperature within the range of 150~200℃; use the fourth-generation UFC cooling equipment for online quenching, the quenching line is 40m long, and uses a liftable slit nozzle. The slit nozzles are arranged at intervals of 0.5m in the direction of steel plate transportation, and the nozzle water pressure is 1MPa, which can be in good contact with the steel plate to achieve full quenching;

[0014] S7, online tempering: send to steam insulation device for tempering, tempering temperature 350±10℃, tempering time 2.5 hours;

[0015] S8, finishing;

[0016] The edge blowing and sucking device is symmetrically arranged between two adjacent rollers; the edge blowing and sucking device includes a negative pressure cylinder, a fixed pipe, an exhaust nozzle, a push frame and a hydraulic cylinder, the output end of the hydraulic cylinder is connected to the push frame, the push frame is fixedly connected to the fixed pipe, the fixed pipe is rotatably installed in the negative pressure cylinder through a bearing to form a negative pressure environment in the negative pressure cylinder, a plurality of negative pressure suction ports for attracting moisture from the edge of the steel plate are opened on the body of the negative pressure cylinder, the exhaust nozzle is fixedly installed on the negative pressure cylinder and is located above the negative pressure suction port, the exhaust nozzle is used to spray high-pressure airflow to the edge of the steel plate to promote the moisture from the edge of the steel plate to flow outward, and the hydraulic cylinder drives the negative pressure cylinder to move in a direction parallel to the axial direction of the roller so that the negative pressure cylinder approaches or moves away from the steel plate.

[0017] The edge blowing and suction device of the present invention also includes a compressed air delivery pipe, a rotary joint, a vacuum generator, a suction telescopic pipe, a guide sleeve, a guide groove, and a guide rod. One end of the fixed pipe is located outside the negative pressure cylinder and is connected to the compressed air delivery pipe, the other end of the compressed air delivery pipe is connected to the high-pressure air source, the other end of the fixed pipe is located in the negative pressure cylinder and is connected to a multi-way pipe through a rotary joint, each port of the multi-way pipe is installed with a vacuum generator, the air source interface of the vacuum generator is connected to the multi-way pipe, the exhaust interface of the vacuum generator is connected to the exhaust nozzle, a plurality of exhaust ports are provided on the exhaust nozzle, the exhaust ports are arranged along the length direction of the exhaust nozzle, the exhaust direction of the exhaust port is inclined downward toward the negative pressure cylinder, the suction interface of the vacuum generator is connected to the suction telescopic pipe, the telescopic end of the suction telescopic pipe is connected to the guide rod, the guide sleeve is coaxially fixedly installed on the fixed pipe, a guide groove forming a closed loop is provided on the inner wall of the guide sleeve, the upper end of the guide rod is slidably installed in the guide groove, and the guide rod moves up and down when moving along the guide groove trajectory.

[0018] The guide groove of the present invention comprises a high horizontal section, a downward inclined section, a low horizontal section and an upward inclined section which are connected in sequence, and the high horizontal section is located above the low horizontal section.

[0019] The push frame of the present invention is also fixed with an arc-shaped baffle plate, on which a sealing strip which is slidably and sealingly connected with the negative pressure cylinder is fixed, and the sealing strip is used for sealing the negative pressure suction port.

[0020] A fixed shaft is coaxially fixedly installed at the bottom of the negative pressure cylinder of the present invention, and the fixed shaft is rotatably installed on the push frame.

[0021] The steam insulation device of the present invention comprises a heating furnace drum, a heating furnace, a steam pipeline, a high-temperature exhaust gas pipeline, a steam superheating device, and a tempering device. The steam of the heating furnace drum is passed into the tempering device through the steam pipeline. The steam superheating device is connected in series to the steam pipeline. The exhaust gas of the heating furnace enters the steam superheating device through the high-temperature exhaust gas pipeline and is discharged after heat exchange with the steam. The steam of the heating furnace drum is heated by using the heat of the heating furnace flue gas, and then the steam is passed into the tempering device for tempering, which greatly utilizes the waste heat of the steel rolling workshop and reduces the energy consumption of the tempering device.

[0022] The tempering device of the present invention is equipped with a temperature measuring device, and a regulating valve is installed on the steam superheating pipeline. The temperature measuring device and the regulating valve are both electrically connected to the temperature automatic control device.

[0023] In the rough rolling process of the present invention, the rough rolling adopts high temperature, large reduction and fast rolling technology, and the maximum pass reduction is selected in the reduction procedure. The first stage rolling temperature is ≥1060°C, and the final rolling temperature is ≥1000°C. After the rough rolling widening is completed, the pass reduction is ensured to increase pass by pass, and the reduction rate of the last three consecutive passes is ≥20%. The thickness of the intermediate billet is controlled according to 2.2H-4H, and H is the thickness of the final product.

[0024] In the finishing rolling process of the present invention, the rolling temperature in the second stage is adjusted according to the thickness of the final finished product, the rolling temperature of thin specifications is high, and the rolling temperature of thick specifications is low, which is controlled within the range of 900-1020°C (adjusted according to the specifications); the total number of passes is 6-8, and in order to ensure that the reduction amount of the plate shape passes decreases pass by pass, the cumulative reduction rate of the last three passes is greater than 10%, and the final rolling temperature is controlled within the range of 840-870°C (adjusted according to the specifications of the finished product); after rolling, a 9-roll pre-straightening machine is used for straightening, and the straightening force is adjusted according to the specifications and the plate shape, so as to ensure the straightness of the plate shape.

[0025] Beneficial effects of the present invention:

[0026] 1. The wear-resistant steel production process of the present invention performs online quenching, online tempering and finishing after rolling, thereby avoiding the process of cooling and then heating before heat treatment in the existing process of rolling, finishing, quenching and tempering, effectively reducing the energy consumption of wear-resistant steel production and reducing the tendency of quenching cracking;

[0027] 2. The steel plate raw material adopts a design without adding V components, which effectively reduces the cost of wear-resistant steel and improves the welding performance and low-temperature toughness of NM400;

[0028] 3. The heat of the heating furnace drum steam and the flue gas of the heating furnace is used for tempering, which greatly utilizes the waste heat of the steel rolling workshop and reduces the energy consumption of the tempering device;

[0029] 4. Through the online quenching and tempering process, the time interval between quenching and tempering is reduced, effectively avoiding the tendency of stress cracking of wear-resistant steel;

[0030] 5. Direct delivery after rolling without quenching and tempering heat treatment, reducing the production cost of the process;

[0031] 6. Use the edge blowing and suction device to absorb moisture from the edge of the steel plate. The negative pressure cylinder contacts the moving steel plate and rotates passively. The moisture from the edge of the steel plate is sucked in through the negative pressure suction port, and the moisture from the edge of the steel plate is promoted to flow to the edge. When the exhaust nozzle rotates to the top of the steel plate, it sprays air to the edge of the steel plate through the exhaust port to promote the moisture from the edge of the steel plate to flow to the edge. After the exhaust nozzle rotates away from the steel plate, the suction telescopic tube descends to the bottom of the negative pressure cylinder to suck in the accumulated cooling water, and the cooling water is sprayed out by the exhaust nozzle to reduce the residual moisture on the edge of the steel plate, so that the steel plate is cooled evenly and the production quality of the steel plate is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a partial top view of the roller table and the edge blowing and suction device in the online quenching process of the present invention;

[0033] Figure 2 yes Figure 1 A partial enlarged view of the blowing and suction device in the middle edge;

[0034] Figure 3 It is a front view of the UFC cooling equipment, roller table and edge blowing and suction device in the online quenching process of the present invention;

[0035] Figure 4 It is a working state diagram of the UFC cooling equipment, roller table and edge blowing and suction device in the online quenching process of the present invention;

[0036] Figure 5 yes Figure 3 A partial enlarged view of the middle A;

[0037] Figure 6 It is a side view of the UFC cooling equipment, roller table and edge blowing and suction device in the online quenching process of the present invention;

[0038] Figure 7 yes Figure 6 A partial enlarged view of the blowing and suction device in the middle edge;

[0039] Figure 8 It is a partial top view of the edge blowing and suction device;

[0040] Fig. 9 It is a structural block diagram of the steam heat preservation device of the present invention;

[0041] In the figure, 1, UFC cooling equipment; 2, edge blowing and suction device; 201, negative pressure cylinder; 202, fixed pipe; 203, exhaust nozzle; 204, push frame; 205, hydraulic cylinder; 206, bearing; 207, negative pressure suction port; 208, compressed air delivery pipe; 209, rotary joint; 210, vacuum generator; 211, suction telescopic pipe; 212, guide sleeve; 213, guide groove; 214, guide rod; 215, multi-way pipe; 216, exhaust port; 21 7. High-level horizontal section; 218. Inclined downward section; 219. Low-level horizontal section; 220. Inclined upward section; 221. Arc baffle; 222. Sealing strip; 223. Fixed shaft; 3. Steel plate; 4. Roller; 5. Steam insulation device; 51. Heating furnace drum; 52. Heating furnace; 53. Steam pipeline; 54. High-temperature exhaust gas pipeline; 55. Steam superheating device; 56. Tempering device; 57. Temperature measuring device; 58. Regulating valve; 59. Automatic temperature control device. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the specific implementation methods described herein are only used to explain the present invention and do not limit the scope of protection of the present invention.

[0043] Example 1

[0044] The method for producing wear-resistant steel by online heat treatment process comprises the following steps:

[0045] S1. Preparation of continuous casting billet; the chemical composition of the continuous casting billet is C=0.20%~0.28%, Si=0.20~0.40, Mn=1.45~1.55, P≤0.015, S≤0.005, Als=0.015~0.030, Nb=0.020~0.030, Ti=0.020~0.030, B=0.002~0.005, and the balance is Fe and unavoidable impurities; raw materials are prepared according to the above composition, and the continuous casting billet with the above composition and mass percentage is obtained through the steps of hot metal desulfurization, converter smelting, refining, RH vacuum refining and continuous casting; the continuous casting billet with a thickness of 180mm is used to roll the steel plate with a thickness of 12-25mm;

[0046] S2, slow cooling of the steel billet: the steel billet is slowly cooled in the slow cooling pit, and then put into the furnace for heating after 24 hours of slow cooling;

[0047] S3. Billet heating: furnace temperature ≤ 500℃, heating process should ensure full solid solution of niobium alloy and fine and uniform original austenite grains, heating section temperature controlled at 1250±20℃, soaking temperature controlled at 1210±20℃, heating time controlled at 8~10min / cm, soaking time controlled at 40-60min, furnace exit temperature controlled at 1100±20℃;

[0048] S4, rough rolling; Rough rolling adopts high temperature, large reduction and fast rolling technology. The maximum pass reduction is selected in the reduction procedure. The start rolling temperature of stage I is ≥1060℃, and the final rolling temperature is ≥1000℃. After the rough rolling widening is completed, the pass reduction is ensured to increase pass by pass, and the reduction rate of the last three consecutive passes is ≥20%. The thickness of the intermediate billet is controlled according to 2.2H-4H, and H is the thickness of the final product;

[0049] S5, finishing rolling; the rolling temperature in stage II is adjusted according to the thickness of the final product, the rolling temperature of thin specifications is high, and the rolling temperature of thick specifications is low, which is controlled in the range of 900-1020℃ (adjusted according to specifications); the total number of passes is 6-8, and the reduction of each pass decreases gradually to ensure the plate shape. The cumulative reduction rate of the last three passes is greater than 10%, and the final rolling temperature is controlled in the range of 840-870℃ (adjusted according to the specifications of the finished product); after rolling, a 9-roll pre-straightening machine is used for straightening, and the straightening force is adjusted according to the specifications and plate shape to ensure the straightness of the plate shape;

[0050] S6, online quenching; use UFC cooling equipment 1 for online quenching, use edge blowing and suction device 2 to absorb moisture from the edge of steel plate 3, control the cooling temperature after rolling within the range of 830-860℃, and control the red-returning temperature within the range of 150-200℃; use the fourth-generation UFC cooling equipment 1 for online quenching, the quenching line is 40m long, and adopts liftable slit nozzles, which are arranged at intervals of 0.5m in the transportation direction of steel plate 3, and the water outlet pressure of the nozzle is 1MPa, which can be well contacted with steel plate 3 to achieve full quenching;

[0051] S7, online tempering; send to steam insulation device 5 for tempering, tempering temperature 350±10℃, tempering time 2.5 hours;

[0052] S8, finishing.

[0053] Example 2

[0054] The method for producing wear-resistant steel by online heat treatment process comprises the following steps:

[0055] S1. Preparation of continuous casting billet; the chemical composition of the continuous casting billet is C=0.20%~0.28%, Si=0.20~0.40, Mn=1.45~1.55, P≤0.015, S≤0.005, Als=0.015~0.030, Nb=0.020~0.030, Ti=0.020~0.030, B=0.002~0.005, and the balance is Fe and unavoidable impurities; raw materials are prepared according to the above composition, and the continuous casting billet with the above composition and mass percentage is obtained through hot metal desulfurization, converter smelting, refining, RH vacuum refining, and continuous casting processes; the 250mm continuous casting billet is used to roll a steel plate 3 with a thickness of 25-35mm;

[0056] S2, slow cooling of the steel billet: the steel billet is slowly cooled in the slow cooling pit, and then put into the furnace for heating after 24 hours of slow cooling;

[0057] S3. Billet heating: furnace temperature ≤ 500℃, heating process should ensure full solid solution of niobium alloy and fine and uniform original austenite grains, heating section temperature controlled at 1250±20℃, soaking temperature controlled at 1210±20℃, heating time controlled at 8~10min / cm, soaking time controlled at 40-60min, furnace exit temperature controlled at 1100±20℃;

[0058] S4, rough rolling; Rough rolling adopts high temperature, large reduction and fast rolling technology. The maximum pass reduction is selected in the reduction procedure. The start rolling temperature of stage I is ≥1060℃, and the final rolling temperature is ≥1000℃. After the rough rolling widening is completed, the pass reduction is ensured to increase pass by pass, and the reduction rate of the last three consecutive passes is ≥20%. The thickness of the intermediate billet is controlled according to 2.2H-4H, and H is the thickness of the final product;

[0059] S5, finishing rolling; the rolling temperature in stage II is adjusted according to the thickness of the final product, the rolling temperature of thin specifications is high, and the rolling temperature of thick specifications is low, which is controlled in the range of 900-1020℃ (adjusted according to specifications); the total number of passes is 6-8, and the reduction of each pass decreases gradually to ensure the plate shape. The cumulative reduction rate of the last three passes is greater than 10%, and the final rolling temperature is controlled in the range of 840-870℃ (adjusted according to the specifications of the finished product); after rolling, a 9-roll pre-straightening machine is used for straightening, and the straightening force is adjusted according to the specifications and plate shape to ensure the straightness of the plate shape;

[0060] S6, online quenching; use UFC cooling equipment 1 for online quenching, use edge blowing and suction device 2 to absorb moisture from the edge of steel plate 3, control the cooling temperature after rolling within the range of 830-860℃, and control the red-returning temperature within the range of 150-200℃; use the fourth-generation UFC cooling equipment 1 for online quenching, the quenching line is 40m long, and adopts liftable slit nozzles, which are arranged at intervals of 0.5m in the transportation direction of steel plate 3, and the water outlet pressure of the nozzle is 1MPa, which can be well contacted with steel plate 3 to achieve full quenching;

[0061] S7, online tempering; send to steam insulation device 5 for tempering, tempering temperature 350±10℃, tempering time 2.5 hours;

[0062] S8, finishing.

[0063] Example 3

[0064] The method for producing wear-resistant steel by online heat treatment process comprises the following steps:

[0065] S1. Preparation of continuous casting billet; the chemical composition of the continuous casting billet is C=0.20%~0.28%, Si=0.20~0.40, Mn=1.45~1.55, P≤0.015, S≤0.005, Als=0.015~0.030, Nb=0.020~0.030, Ti=0.020~0.030, B=0.002~0.005, and the balance is Fe and unavoidable impurities; raw materials are prepared according to the above composition, and the continuous casting billet with the above composition and mass percentage is obtained through hot metal desulfurization, converter smelting, refining, RH vacuum refining, and continuous casting processes; 320mm specification continuous casting billet is used to roll a steel plate 3 with a thickness of 35-40mm;

[0066] S2, slow cooling of the steel billet: the steel billet is slowly cooled in the slow cooling pit, and then put into the furnace for heating after 24 hours of slow cooling;

[0067] S3. Billet heating: furnace temperature ≤ 500℃, heating process should ensure full solid solution of niobium alloy and fine and uniform original austenite grains, heating section temperature controlled at 1250±20℃, soaking temperature controlled at 1210±20℃, heating time controlled at 8~10min / cm, soaking time controlled at 40-60min, furnace exit temperature controlled at 1100±20℃;

[0068] S4, rough rolling; Rough rolling adopts high temperature, large reduction and fast rolling technology. The maximum pass reduction is selected in the reduction procedure. The start rolling temperature of stage I is ≥1060℃, and the final rolling temperature is ≥1000℃. After the rough rolling widening is completed, the pass reduction is ensured to increase pass by pass, and the reduction rate of the last three consecutive passes is ≥20%. The thickness of the intermediate billet is controlled according to 2.2H-4H, and H is the thickness of the final product;

[0069] S5, finishing rolling; the rolling temperature in stage II is adjusted according to the thickness of the final product, the rolling temperature of thin specifications is high, and the rolling temperature of thick specifications is low, which is controlled in the range of 900-1020℃ (adjusted according to specifications); the total number of passes is 6-8, and the reduction of each pass decreases gradually to ensure the plate shape. The cumulative reduction rate of the last three passes is greater than 10%, and the final rolling temperature is controlled in the range of 840-870℃ (adjusted according to the specifications of the finished product); after rolling, a 9-roll pre-straightening machine is used for straightening, and the straightening force is adjusted according to the specifications and plate shape to ensure the straightness of the plate shape;

[0070] S6, online quenching; use UFC cooling equipment 1 for online quenching, use edge blowing and suction device 2 to absorb moisture from the edge of steel plate 3, control the cooling temperature after rolling within the range of 830-860℃, and control the red-returning temperature within the range of 150-200℃; use the fourth-generation UFC cooling equipment 1 for online quenching, the quenching line is 40m long, and adopts liftable slit nozzles, which are arranged at intervals of 0.5m in the transportation direction of steel plate 3, and the water outlet pressure of the nozzle is 1MPa, which can be well contacted with steel plate 3 to achieve full quenching;

[0071] S7, online tempering; send to steam insulation device 5 for tempering, tempering temperature 350±10℃, tempering time 2.5 hours;

[0072] S8, finishing.

[0073] The NM400 steel plate 3 prepared by the method provided in Examples 1-3 has a thickness of 12-40 mm, a Brinell hardness of 370-430 HB, an impact energy of ≥40 J at -20°C, and various properties meeting the requirements of the national standard GB / T 24186-2009.

[0074] Example 4

[0075] This embodiment provides an online heat treatment device for producing wear-resistant steel by an online heat treatment process, comprising a UFC cooling device 1, an edge blowing and suction device 2, and a steam insulation device 5;

[0076] The roller 4 conveys the steel plate 3, and the roller 4 is driven to rotate by the roller 4 motor;

[0077] The edge blowing and suction device 2 is symmetrically arranged between two adjacent rollers 4; the edge blowing and suction device 2 is arranged at intervals in the conveying direction of the roller 4, and the edge blowing and suction device 2 includes a negative pressure cylinder 201, a fixed pipe 202, an exhaust nozzle 203, a push frame 204 and a hydraulic cylinder 205. The output end of the hydraulic cylinder 205 is connected to the push frame 204, and the push frame 204 is fixedly connected to the fixed pipe 202. The fixed pipe 202 is rotatably installed in the negative pressure cylinder 201 through a bearing 206 and makes the negative pressure cylinder 201 form a A negative pressure environment is formed, and a plurality of negative pressure suction ports 207 for sucking moisture from the edge of the steel plate 3 are provided on the body of the negative pressure cylinder 201. The exhaust nozzle 203 is fixedly mounted on the negative pressure cylinder 201 and is located above the negative pressure suction port 207. The exhaust nozzle 203 is used to spray high-pressure airflow to the edge of the steel plate 3 to promote the moisture from the edge of the steel plate 3 to flow outward. The hydraulic cylinder 205 drives the negative pressure cylinder 201 to move in a direction parallel to the axial direction of the roller 4, so that the negative pressure cylinder 201 is close to or away from the steel plate 3. The bottom of the negative pressure cylinder 201 is lower than the top of the roller 4, so as to contact the steel plate 3 conveyed on the roller 4.

[0078] The edge blowing and suction device 2 of the present embodiment also includes a compressed air delivery pipe 208, a rotary joint 209, a vacuum generator 210, a suction telescopic pipe 211, a guide sleeve 212, a guide groove 213, and a guide rod 214. One end of the fixed pipe 202 is located outside the negative pressure cylinder 201 and is connected to the compressed air delivery pipe 208. The other end of the compressed air delivery pipe 208 is connected to a high-pressure air source. The other end of the fixed pipe 202 is located inside the negative pressure cylinder 201 and is connected to a multi-way pipe 215 through a rotary joint 209. Each port of the multi-way pipe 215 is installed with a vacuum generator 210. In the present embodiment, four vacuum generators 210 are arranged. The air source interface of the vacuum generator 210 is connected to the multi-way pipe 215. The air interface is connected to the exhaust nozzle 203, and the exhaust nozzle 203 is distributed in a circle on the negative pressure cylinder 201. A plurality of exhaust ports 216 are provided on the exhaust nozzle 203, and the exhaust ports 216 are arranged along the length direction of the exhaust nozzle 203. The exhaust direction of the exhaust ports 216 is inclined downward toward the negative pressure cylinder 201. The suction interface of the vacuum generator 210 is connected to the suction telescopic tube 211, and the telescopic end of the suction telescopic tube 211 is connected to the guide rod 214. The guide sleeve 212 is coaxially fixedly installed on the fixed tube 202. A guide groove 213 forming a closed loop is provided on the inner wall of the guide sleeve 212. The upper end of the guide rod 214 is slidably installed in the guide groove 213. When the guide rod 214 moves along the trajectory of the guide groove 213, it will move up and down.

[0079] The guide groove 213 of this embodiment has a high horizontal section 217 , a downward inclined section 218 , a low horizontal section 219 and an upward inclined section 220 connected in sequence, and the high horizontal section 217 is located above the low horizontal section 219 . When the guide rod 214 moves to the high horizontal section 217, the exhaust nozzle 203 rotates roughly to the top of the steel plate 3, and can spray toward the edge of the steel plate 3 through the exhaust port 216; when the guide rod 214 moves to the inclined downward section 218, the exhaust nozzle 203 rotates roughly to away from the top of the steel plate 3, and the guide rod 214 moves on the inclined downward section 218 and will gradually descend, driving the bottom of the suction telescopic tube 211 to descend and gradually approach the bottom of the negative pressure cylinder 201; when the guide rod 214 moves to the inclined downward section 218, the guide rod 214 descends to the lowest point, and drives the bottom of the suction telescopic tube 211 to descend to close to the bottom of the negative pressure cylinder 201; when the guide rod 214 moves to the inclined upward section 220, the exhaust nozzle 203 rotates to gradually approach the steel plate 3, and the guide rod 214 moves on the inclined upward section 220 and will gradually rise, driving the bottom of the suction telescopic tube 211 to rise and gradually away from the bottom of the negative pressure cylinder 201.

[0080] The push frame 204 of this embodiment is also fixed with an arc-shaped baffle plate 221, and a sealing strip 222 is fixed on the arc-shaped baffle plate 221, which is slidably sealed and connected with the negative pressure cylinder 201, and the sealing strip 222 is used to seal the negative pressure suction port 207. The sealing strip 222 is arranged at the lower periphery of the low-level horizontal section 219, the downwardly inclined section 218 and the upwardly inclined section 220. When the exhaust nozzle 203 starts to spray water, the sealing strip 222 has covered the negative pressure suction port 207 below the exhaust nozzle 203, so as to prevent the drainage from spraying into the negative pressure suction port 207.

[0081] The bottom of the negative pressure cylinder 201 of this embodiment is coaxially fixed with a fixed shaft 223, and the fixed shaft 223 is rotatably mounted on the push frame 204. The fixed shaft 223 can increase the connection strength between the negative pressure cylinder 201 and the push frame 204, and avoid the negative pressure cylinder 201 being connected to the push frame 204 only through the fixed tube 202, which is too low in strength and causes the fixed tube 202 to break.

[0082] The steam insulation device 5 of this embodiment includes a heating furnace drum 51, a heating furnace 52, a steam pipe 53, a high-temperature exhaust gas pipe 54, a steam superheating device 55, and a tempering device 56. The steam of the heating furnace drum 51 passes through the steam pipe 53 to the tempering device 56. The steam superheating device 55 is connected in series to the steam pipe 53. The exhaust gas of the heating furnace 52 enters the steam superheating device 55 through the high-temperature exhaust gas pipe 54 and is discharged after heat exchange with the steam. The temperature of the steam output from the heating furnace drum 51 is about 280 degrees, and the temperature of the high-temperature exhaust gas output from the heating furnace 52 to the high-temperature exhaust gas pipe 54 is about 600 degrees. The heat of the flue gas of the heating furnace 52 is used to heat the steam of the heating furnace drum 51, and then the steam of about 400 degrees after heat exchange is passed into the tempering device 56 for tempering, which greatly utilizes the waste heat of the steel rolling workshop and reduces the energy consumption of the tempering device 56. The waste gas after heat exchange transported by the high-temperature waste gas pipeline 54 to the steam superheating device 55 is discharged after being desulfurized and denitrated, and the steam discharged from the tempering device enters the waste heat power plant.

[0083] In the tempering device 56 of this embodiment, a temperature measuring device 57 is installed inside, and a regulating valve 58 is installed on the steam superheating pipe. The temperature measuring device 57 and the regulating valve 58 are both electrically connected to the temperature automatic control device 59. The temperature inside the tempering device 56 is detected by the temperature measuring device 57, and the temperature automatic control device 59 adjusts the regulating valve 58 according to the detected temperature. When the temperature is too high, the opening of the regulating valve 58 is reduced to reduce the amount of steam entering. On the contrary, the opening is increased to increase the amount of steam entering to quickly increase the temperature.

[0084] After the finishing rolling is completed, the roller 4 rotates to drive the steel plate 3 to be quenched to move to the UFC cooling device 1. The nozzle of the UFC cooling device 1 sprays water to the passing steel plate 3. The water outlet pressure is 1MPa, which can be in good contact with the steel plate 3 to achieve full cooling.

[0085] The hydraulic cylinders 205 work synchronously, and the telescopic ends of the hydraulic cylinders 205 extend out, driving the two push racks 204 and the negative pressure cylinder 201 between the same roller table 4 gap to move toward each other, so that the negative pressure cylinder 201 abuts against the edge of the steel plate 3. When the steel plate 3 moves, the negative pressure cylinder 201 rotates due to the friction of the steel plate 3; the high-pressure air source delivers high-pressure airflow to the compressed air delivery pipe 208, the fixed pipe 202, the rotary joint 209, and the multi-way pipe 215, and the high-pressure airflow enters the air source interface of the vacuum generator 210, and the suction interface of the vacuum generator 210 generates a negative The negative pressure cylinder 201 is evacuated by pressure, so that a negative pressure environment is formed in the negative pressure cylinder 201, and the moisture at the edge of the steel plate 3 is attracted by the negative pressure suction port 207, so that the moisture is promoted to flow to the edge of the steel plate 3. Part of the moisture directly enters the negative pressure cylinder 201 under the suction force of the negative pressure suction port 207 and accumulates at the bottom of the negative pressure cylinder 201. Part of the moisture quickly flows down from the edge of the steel plate 3 under the suction force of the negative pressure suction port 207, so as to promote the discharge of moisture at the edge of the steel plate 3. The exhaust interface of the vacuum generator 210 is connected to the exhaust nozzle 203, so that the exhaust nozzle 203 discharges high-pressure airflow.

[0086] As the negative pressure cylinder 201 rotates, the guide rod 214 moves in the guide groove 213. When the guide rod 214 moves to the high horizontal section 217, the exhaust nozzle 203 rotates to the top of the steel plate 3, and sprays air to the edge of the steel plate 3 through the exhaust port 216, promoting the flow of moisture from the edge of the steel plate 3 to the edge; when the guide rod 214 moves to the downward inclined section 218, the exhaust nozzle 203 rotates away from the top of the steel plate 3, and the guide rod 214 gradually descends, driving the bottom of the suction telescopic tube 211 to descend. Gradually approach the bottom of the negative pressure cylinder 201; when the guide rod 214 moves to the inclined downward section 218, the guide rod 214 drops to the lowest point, and drives the bottom of the suction telescopic tube 211 to drop close to the bottom of the negative pressure cylinder 201, and the bottom of the suction telescopic tube 211 is immersed in the cooling water sucked by the negative pressure suction port 207. Under the negative pressure of the suction interface of the vacuum generator 210, the suction telescopic tube 211 sucks the cooling water, and the exhaust nozzle 203 sprays the cooling water to avoid water accumulation in the negative pressure cylinder 201 Too much cooling water causes the exhaust nozzle 203 to spray cooling water toward the steel plate 3 again; when the guide rod 214 moves to the inclined upward section 220, the exhaust nozzle 203 rotates and gradually approaches the steel plate 3, and the guide rod 214 gradually rises, driving the bottom of the suction telescopic tube 211 to rise and gradually move away from the bottom of the negative pressure cylinder 201, and finally the bottom of the suction telescopic tube 211 is higher than the water level in the negative pressure cylinder 201; according to the drainage rate of the exhaust nozzle 203, the number and aperture of the negative pressure suction port 207 are set to avoid water ingress The rate is greater than the drainage rate; in addition, when the guide rod 214 corresponding to the exhaust nozzle 203 moves to be separated from the high horizontal section 217, the exhaust nozzle 203 may no longer exhaust but drain water, and the sealing strip 222 is arranged at the lower periphery of the low horizontal section 219, the downward inclined section 218 and the upward inclined section 220. When the exhaust nozzle 203 starts to spray water, the sealing strip 222 has covered the negative pressure suction port 207 below the exhaust nozzle 203 to prevent the drainage from spraying into the negative pressure suction port 207;

[0087] After the online quenching, the steel plate 3 is transported to the tempering device 56 of the steam insulation device 5. The steam in the heating furnace drum 51 first enters the steam superheating device 55, and the heat of the flue gas of the heating furnace 52 is used to heat the steam in the steam superheating device 55. The steam is then passed into the tempering device 56 for tempering, which greatly utilizes the waste heat of the steel rolling workshop and reduces the energy consumption of the tempering device 56.

[0088] The above technical solutions only reflect the preferred technical solutions of the technical solutions of the present invention. Some changes that may be made to certain parts thereof by technicians in this technical field all reflect the principles of the present invention and fall within the protection scope of the present invention.

[0089] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0090] In the present invention, "first" and "second" do not represent specific numbers and orders, but are only used to distinguish names.

[0091] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

Claims

1. A device for producing wear-resistant steel by online heat treatment process, characterized in that: The edge blowing and suction device (2) is symmetrically arranged between two adjacent rollers (4); the edge blowing and suction device (2) comprises a negative pressure cylinder (201), a fixed pipe (202), an exhaust nozzle (203), a push frame (204) and a hydraulic cylinder (205); the output end of the hydraulic cylinder (205) is connected to the push frame (204); the push frame (204) is fixedly connected to the fixed pipe (202); the fixed pipe (202) is rotatably installed in the negative pressure cylinder (201) through a bearing (206) and forms a negative pressure environment in the negative pressure cylinder (201); The body of the cylinder (201) is provided with a plurality of negative pressure suction ports (207) for sucking moisture from the edge of the steel plate (3); an exhaust nozzle (203) is fixedly mounted on the negative pressure cylinder (201) and is located above the negative pressure suction port (207); the exhaust nozzle (203) is used to spray high-pressure airflow toward the edge of the steel plate (3) to promote the moisture from the edge of the steel plate (3) to flow outward; the hydraulic cylinder (205) drives the negative pressure cylinder (201) to move in a direction parallel to the axial direction of the roller table (4) so ​​as to move the negative pressure cylinder (201) closer to or farther away from the steel plate (3); The edge blowing and suction device (2) further comprises a compressed air delivery pipe (208), a rotary joint (209), a vacuum generator (210), a suction telescopic pipe (211), a guide sleeve (212), a guide groove (213), and a guide rod (214); one end of the fixed pipe (202) is located outside the negative pressure cylinder (201) and is connected to the compressed air delivery pipe (208); the other end of the compressed air delivery pipe (208) is connected to a high-pressure air source; the other end of the fixed pipe (202) is located inside the negative pressure cylinder (201) and is connected to a multi-way pipe (215) via a rotary joint (209); each port of the multi-way pipe (215) is installed with a vacuum generator (210); the air source interface of the vacuum generator (210) is connected to the multi-way pipe (215); the vacuum generator (210) The exhaust interface of the vacuum generator (210) is connected to the exhaust nozzle (203), and a plurality of exhaust ports (216) are provided on the exhaust nozzle (203). The exhaust ports (216) are arranged along the length direction of the exhaust nozzle (203), and the exhaust direction of the exhaust ports (216) is inclined downward toward the negative pressure cylinder (201). The suction interface of the vacuum generator (210) is connected to the suction telescopic tube (211), and the telescopic end of the suction telescopic tube (211) is connected to the guide rod (214). The guide sleeve (212) is coaxially fixedly mounted on the fixed tube (202), and a guide groove (213) forming a closed loop is provided on the inner wall of the guide sleeve (212). The upper end of the guide rod (214) is slidably mounted in the guide groove (213), and the guide rod (214) moves up and down when moving along the trajectory of the guide groove (213).

2. The device for producing wear-resistant steel by online heat treatment process according to claim 1, characterized in that: The guide groove (213) comprises a high horizontal section (217), a downward inclined section (218), a low horizontal section (219) and an upward inclined section (220) which are connected in sequence, and the high horizontal section (217) is located above the low horizontal section (219).

3. The device for producing wear-resistant steel by online heat treatment process according to claim 2, characterized in that: The push frame (204) is also fixed with an arc-shaped baffle (221), and a sealing strip (222) that is slidably and sealingly connected to the negative pressure cylinder (201) is fixed on the arc-shaped baffle (221), and the sealing strip (222) is used to seal the negative pressure suction port (207).

4. The device for producing wear-resistant steel by online heat treatment process according to any one of claims 1 to 3, characterized in that: A fixed shaft (223) is coaxially fixedly mounted on the bottom of the negative pressure cylinder (201), and the fixed shaft (223) is rotatably mounted on the push frame (204).

5. The device for producing wear-resistant steel by online heat treatment process according to claim 1, characterized in that: The steam insulation device (5) comprises a heating furnace drum (51), a heating furnace (52), a steam pipeline (53), a high-temperature exhaust gas pipeline (54), a steam superheating device (55), and a tempering device (56). The steam of the heating furnace drum (51) passes through the steam pipeline (53) into the tempering device (56). The steam superheating device (55) is connected in series to the steam pipeline (53). The exhaust gas of the heating furnace (52) passes through the high-temperature exhaust gas pipeline (54) into the steam superheating device (55) and is discharged after heat exchange with the steam.

6. The device for producing wear-resistant steel by online heat treatment process according to claim 5, characterized in that: A temperature measuring device (57) is installed in the tempering device (56), and a regulating valve (58) is installed on the steam superheating pipe. The temperature measuring device (57) and the regulating valve (58) are both electrically connected to the automatic temperature control device (59).

7. The method for producing wear-resistant steel according to the device of claim 1, characterized in that: The method for producing wear-resistant steel comprises the following steps: S1. Preparation of continuous casting billet; the chemical composition mass percentage of the continuous casting billet is C=0.20%~0.28%, Si=0.20~0.40, Mn=1.45~1.55, P≤0.015, S≤0.005, Als=0.015~0.030, Nb=0.020~0.030, Ti=0.020~0.030, B=0.002~0.005, and the balance is Fe and unavoidable impurities; S2, slow cooling of the steel billet: the steel billet is slowly cooled in the slow cooling pit; S3, billet heating; furnace temperature ≤ 500 ℃, heating section temperature controlled at 1250 ± 20 ℃, soaking temperature controlled at 1210 ± 20 ℃, heating time controlled at 8 ~ 10min / cm, soaking section time controlled at 40-60min, furnace exit temperature controlled at 1100 ± 20 ℃; S4, rough rolling; S5, finishing rolling; S6, online quenching; using UFC cooling equipment (1) to perform online quenching, using edge blowing and suction device (2) to absorb moisture from the edge of the steel plate (3), controlling the cooling temperature after rolling to be within the range of 830-860°C, and controlling the red-returning temperature to be within the range of 150-200°C; S7, online tempering; sending to the steam insulation device (5) for tempering, the tempering temperature is 350±10℃, and the tempering time is 2.5 hours; S8, finishing.

8. The method for producing wear-resistant steel according to claim 7, characterized in that: The final rolling temperature in the finishing rolling stage is 840-870°C.

9. The method for producing wear-resistant steel according to claim 7, characterized in that: The starting rolling temperature of the rough rolling stage I is ≥1060°C, and the final rolling temperature is ≥1000°C. After the rough rolling widening is completed, the reduction rate of each pass is ensured to increase pass by pass, and finally the reduction rate of three consecutive passes is ≥20%.

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