Treatment process for eliminating cross fold defect on surface of hot-rolled wide strip sheet stainless steel

Abstract

The invention discloses a treatment process for eliminating cross fold defects on the surface of hot-rolled wide strip sheet stainless steel. The treatment process comprises the following specific process steps: 1) heating; 2) descaling with high-pressure water; (3) rough rolling; 4) finish rolling; 5) laminar cooling; (6) coiling; cooling equipment in the step 5) comprises a water retaining mechanism, an edge shielding mechanism, a laminar cooling mechanism, a water receiving tank and a correcting mechanism; the correcting mechanism is arranged at one end of the water receiving tank, the edge shielding mechanisms are symmetrically arranged on the two sides of the water receiving tank, and the laminar cooling mechanisms are fixedly connected to the water receiving tank at equal intervals. The multiple water retaining mechanisms are fixedly connected to one side of the laminar cooling mechanism. The water retaining mechanism in the cooling equipment is controlled to locally shield and guide the laminar cooling mechanism, and the problem that the transverse temperature of the wide-band sheet stainless steel is not uniform is solved by reducing the local cooling strength.

Description

Technical Field

[0001] This invention belongs to the field of hot rolling technology, and specifically relates to a process for eliminating transverse fold defects on the surface of hot-rolled wide stainless steel sheets. Background Technology

[0002] During the production of hot-rolled stainless steel, uneven cooling temperature of hot-rolled stainless steel strip, especially transverse temperature difference, will lead to uneven microstructure and mechanical properties of stainless steel. This difference will cause the strip to deform uncoordinatedly during subsequent leveling or stretching, and the soft material will buckle under pressure, thus causing transverse bending defects.

[0003] After searching, the existing technology disclosure number CN118060351A is a hot-rolled laminar flow cooling system. However, the upper and lower cooling manifolds are usually arranged in segments and discretely, and there are physical gaps between each manifold. This may cause the cooling intensity of the strip to fluctuate when it passes through these gap areas, forming a periodic transverse temperature difference on a macroscopic scale.

[0004] A search revealed a method for controlling transverse wrinkles in hot-rolled strip steel, with publication number CN120115539A. This method systematically controls the factors affecting the temperature difference of the rolled piece throughout the hot rolling process, and combines this with the principle of phase transformation in steel to eliminate transverse wrinkles caused by the temperature difference between the upper and lower surfaces of the rolled piece without affecting rolling stability and surface quality. However, this method may also encounter fluctuations in cooling intensity during laminar cooling.

[0005] Therefore, a treatment process is needed to eliminate transverse fold defects on the surface of hot-rolled wide strip stainless steel. This process can achieve stable and uniform cooling of the wide strip stainless steel to prevent transverse fold defects from occurring. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a process for eliminating transverse fold defects on the surface of hot-rolled wide-band stainless steel sheets. This process controls the water-blocking mechanism in the cooling equipment to partially block and guide the laminar flow cooling mechanism, thereby reducing the intensity of local cooling and solving the problem of uneven transverse temperature in wide-band stainless steel sheets.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] The process for eliminating transverse fold defects on the surface of hot-rolled wide stainless steel sheets includes the following steps:

[0009] 1) Heating: The heating process is divided into a preheating section, a first heating section, a second heating section, and a soaking section; the temperature of the preheating section is controlled at 750℃-850℃; the temperature of the first heating section is controlled at 1050℃-1150℃; the temperature of the second heating section is controlled at 1180℃-1250℃; the temperature of the soaking section is controlled at 1200℃-1280℃; and the furnace pressure is controlled at 20-40 Pa.

[0010] 2) High-pressure water descaling: The oxide scale on the surface of the heated steel billet is removed by high-pressure water at 18-22 MPa to prevent the oxide scale from adversely affecting the surface quality of the steel billet during the rolling process.

[0011] 3) Rough rolling: The steel billet is rapidly conveyed to the rough rolling mill via a conveyor device equipped with an insulation cover; during rough rolling, the steel billet is rolled in 7 passes at a rolling speed of 2-3.5 m / s; the reduction rate for the first pass is 20%-25%; the reduction rate for the second pass is 25%-30%; the reduction rate for the third pass is 28%-33%; the reduction rate for the fourth pass is 25%-30%; the reduction rate for the fifth pass is 20%-25%; the reduction rate for the sixth pass is 15%-20%; and the reduction rate for the seventh pass is 10%-15%.

[0012] 4) Finishing rolling: The finishing rolling adopts hot continuous rolling. The steel billet after rough rolling is conveyed into the finishing rolling mechanism to be rolled into wide strip stainless steel. The finishing rolling adopts speed-increasing rolling and pressure AGC is applied. The starting temperature of finishing rolling is set to 1000℃-1050℃; the finishing rolling ending temperature is 850℃-920℃.

[0013] 5) Laminar flow cooling: The temperature of the wide-band thin stainless steel sheet is detected by an infrared thermal imaging temperature measurement system in the cooling equipment; then, the temperature of the wide-band thin stainless steel sheet is reduced to 550℃-650℃ by the laminar flow cooling mechanism; at the same time, the spray range of the laminar flow cooling mechanism is controlled by a water-blocking mechanism, and the edges of the wide-band thin stainless steel sheet are blocked by an edge-shielding mechanism, thereby reducing the transverse temperature difference of the wide-band thin stainless steel sheet; then, the shape of the wide-band thin stainless steel sheet is corrected by a straightening mechanism.

[0014] 6) Coiling: Use an underground coiling machine to roll wide thin stainless steel sheets into steel coils.

[0015] The cooling equipment in step 5) includes a water-blocking mechanism, a side-shielding mechanism, a laminar flow cooling mechanism, a water receiving tank, and a straightening mechanism; the straightening mechanism is located at one end of the water receiving tank, and several side-shielding mechanisms are symmetrically arranged on both sides of the water receiving tank, and several laminar flow cooling mechanisms are fixedly connected to the water receiving tank at equal intervals; several water-blocking mechanisms are provided, and each is fixedly connected to one side of the laminar flow cooling mechanism.

[0016] The water-blocking mechanism includes a water tank, connecting columns, a guide groove, a carrier, and a water receiver; the bottom of the water tank is fixedly connected to the guide groove, and one end of a pair of connecting columns is fixedly connected to both ends of the water tank, and the other end is fixedly connected to the laminar flow cooling mechanism; the carrier is located on one side of the water tank and connected to the guide groove, and the water receiver is located above the water tank and slidably connected to the top of the carrier.

[0017] The carrier includes a protective box I, a guide box, a sliding rod, a spring, a motor I, a motor II, a gear, a sprocket I, a sprocket II, and a roller. One side of the protective box I is slidably connected to a guide groove. Motors I and II are fixedly connected inside the protective box I via connecting seats, and the output end of motor I passes through a through hole in the top of the protective box I and is fixedly connected to the gear. One side of sprocket I and sprocket II is fixedly connected to a roller located in the guide groove via a connecting shaft. The other side of sprocket I is rotatably connected to the protective box I via a connecting shaft, and the other side of sprocket II passes through a through hole in the protective box I via a connecting shaft and is fixedly connected to the output end of motor II. Sprocket I is connected to sprocket II via a chain. A pair of guide boxes are provided, fixedly connected to both sides of the protective box I, and one end of each pair of sliding rods is slidably connected to the pair of guide boxes. A pair of springs are provided, and the springs are located inside the guide boxes along the sliding rods.

[0018] The water receiver includes a connecting plate I, a telescopic groove, a guide pipe, a sliding plate, a rack, a connecting plate II, a protective box I, an electric pusher cylinder I, a connecting plate III, an electric pusher cylinder II, and a baffle. The sliding plate is slidably connected to the guide box at both ends via a sliding groove. The telescopic groove is fixedly connected to a pair of connecting plates I slidably connected to the sliding plate on both sides. One end of each pair of guide pipes is slidably connected to a pair of connecting plates I. The rack is located below the telescopic groove and is fixedly connected to the sliding plate, meshing with a gear. A pair of electric pusher cylinders II are provided, and the cylinder bodies of the pair of electric pusher cylinders II are fixedly connected to the protective box I located on the outer wall of the pair of guide pipes via connecting seats. The protruding ends pass through the through holes on the protective box I and are fixedly connected to one end of the connecting plate II. A pair of baffles are provided, with one end of each baffle slidably connected to a pair of guide pipes and the other end fixedly connected to the connecting plate II. A pair of electric pusher cylinders I are provided, with the cylinder bodies of the pair of electric pusher cylinders I stacked and fixedly connected to one side of the sliding plate via connecting seats. The protruding ends are fixedly connected to a pair of connecting plates I via connecting plate III.

[0019] The water receiving tank is equipped with a squeezing roller at the discharge end, a pinch roller at the feed end, a drain outlet on the side wall, and several transport rollers inside. The correction mechanism is located outside the discharge end of the water receiving tank, and the infrared thermal imaging temperature measurement system is located on one side of the pinch roller and fixedly connected to the water receiving tank.

[0020] The edge shielding mechanism includes an electric push cylinder III, a water baffle, and a rotating roller; there is a pair of electric push cylinders III, and the cylinder bodies of the pair of electric push cylinders III are fixedly connected to the water receiving tank through a connecting seat, and the extended ends pass through the through holes on the water receiving tank and are fixedly connected to the water baffle; there are several rotating rollers, and the several rotating rollers are equidistantly rotatably connected to the inside of the water baffle.

[0021] The laminar flow cooling mechanism includes an upper manifold, a lower manifold, and support columns; both ends of the upper manifold are fixedly connected to the top of a pair of support columns, the lower manifold is located inside the water receiving tank and is fixedly connected to the bottom of a pair of support columns, and the other ends of the pair of connecting columns are fixedly connected to a pair of support columns.

[0022] The connecting flanges at one end of the upper and lower manifolds are fixedly connected to the cooling equipment via the conveying pipeline.

[0023] The advantages of this invention compared to existing technologies are as follows:

[0024] 1) After the low-temperature area is detected by the infrared thermal imaging temperature measurement system, a movable and adjustable water-blocking mechanism is used to partially block and guide the upper manifold in the laminar flow cooling mechanism located above the area, thereby dynamically and accurately reducing the cooling intensity of the area. This effectively solves the problem of uneven lateral temperature that is common in laminar flow cooling equipment, and significantly improves the temperature uniformity and microstructure consistency of wide-band thin-plate stainless steel.

[0025] 2) The edge shielding mechanism uses an electric pusher cylinder III to drive the baffle plate and rotating roller to fit against the edge of the wide-band thin stainless steel plate, physically blocking the direct impact of cooling water, slowing down the cooling rate of the edge, and preventing performance defects or residual stress in the edge of the wide-band thin stainless steel plate due to overcooling; at the same time, the edge shielding mechanism also plays a guiding role while blocking water, preventing the steel plate from deviating during the conveying process, ensuring the stability of the steel plate's lateral position, and keeping the target cooling area and the position of the water shielding mechanism always in correspondence, thus improving the stability and accuracy of the system operation. Attached Figure Description

[0026] Appendix Figure 1 This is a structural diagram of the cooling equipment;

[0027] Appendix Figure 2 It is attached Figure 1 Schematic diagram of the connection structure between the mid-laminar flow cooling mechanism and the water receiving tank;

[0028] Appendix Figure 3 It is attached Figure 1 Schematic diagram of the middle edge shielding mechanism;

[0029] Appendix Figure 4 It is attached Figure 1 Schematic diagram of the central water-blocking mechanism;

[0030] Appendix Figure 5 It is attached Figure 1 Schematic diagram of the connection structure between the medium-sized vehicle and the water receiving device;

[0031] Appendix Figure 6 It is attached Figure 1 A cross-sectional schematic diagram of the central water-blocking mechanism;

[0032] Appendix Figure 7 It is attached Figure 1 Schematic diagram of the medium-sized vehicle;

[0033] Appendix Figure 8 It is attached Figure 1 Schematic diagram of the intermediate water inlet device;

[0034] In the diagram: 1. Water-blocking mechanism; 101. Water tank; 1011. Connecting column; 1012. Guide channel; 102. Carrier; 1021. Protective box I; 1022. Guide box; 1023. Sliding rod; 1024. Spring; 1025. Motor I; 1026. Motor II; 1027. Gear; 1028. Sprocket I; 1029. Sprocket II; 103. Roller; 104. Water receiver; 1041. Connecting plate I; 1042. Telescopic channel; 1043. Guide pipe; 1044. Sliding plate; 1045. Rack; 046. Connecting plate II; 1047. Protective box I; 1048. Electric pusher cylinder I; 1049. Connecting plate III; 105. Electric pusher cylinder II; 1051. Baffle; 2. Side shielding mechanism; 201. Electric pusher cylinder III; 202. Water baffle; 2021. Rotating roller; 3. Laminar flow cooling mechanism; 301. Upper manifold; 302. Lower manifold; 303. Support column; 4. Water receiving tank; 401. Squeeze roller; 402. Pinch roller; 403. Drain outlet; 5. Correction mechanism; 6. Wide strip thin stainless steel; 7. Infrared thermal imaging temperature measurement system. Detailed Implementation

[0035] To facilitate understanding by those skilled in the art, the following is a detailed explanation in conjunction with the appendix. Figure 1-8 The technical solution of the present invention will be further described in detail below.

[0036] Example 1:

[0037] The process for eliminating transverse fold defects on the surface of hot-rolled wide stainless steel sheets includes the following steps:

[0038] 1) Heating: The heating process is divided into a preheating section, a first heating section, a second heating section, and a soaking section; the temperature of the preheating section is controlled at 800℃; the temperature of the first heating section is controlled at 1100℃; the temperature of the second heating section is controlled at 1210℃; the temperature of the soaking section is controlled at 1250℃; and the furnace pressure is controlled at 30 Pa.

[0039] 2) High-pressure water descaling: The oxide scale on the surface of the heated steel billet is removed by high-pressure water at 20 MPa to prevent the oxide scale from adversely affecting the surface quality of the steel billet during the rolling process;

[0040] 3) Rough rolling: The steel billet is rapidly conveyed to the rough rolling mill via a conveyor device equipped with an insulation cover; during rough rolling, the steel billet is rolled in 7 passes at a rolling speed of 2.5 m / s; the reduction rate for the first pass is 22%; the reduction rate for the second pass is 27%; the reduction rate for the third pass is 30%; the reduction rate for the fourth pass is 27%; the reduction rate for the fifth pass is 23%; the reduction rate for the sixth pass is 19%; and the reduction rate for the seventh pass is 13%.

[0041] 4) Finishing rolling: The finishing rolling adopts hot continuous rolling. The steel billet after rough rolling is conveyed into the finishing rolling mechanism to be rolled into wide strip stainless steel 6. The finishing rolling adopts speed-increasing rolling and pressure AGC is applied. The starting temperature of finishing rolling is set to 1000℃; the finishing rolling ending temperature is 875℃.

[0042] 5) Laminar flow cooling: The temperature of the wide-band thin stainless steel plate 6 is detected by the infrared thermal imaging temperature measurement system 7 in the cooling equipment; then the temperature of the wide-band thin stainless steel plate 6 is reduced to 600℃ by the laminar flow cooling mechanism 3; at the same time, the spray range of the laminar flow cooling mechanism 3 is controlled by the water blocking mechanism 1, and the edge of the wide-band thin stainless steel plate 6 is blocked by the edge blocking mechanism 2, thereby reducing the lateral temperature difference of the wide-band thin stainless steel plate 6; then the plate shape of the wide-band thin stainless steel plate 6 is corrected by the straightening mechanism 5.

[0043] 6) Coiling: Use an underground coiling machine to roll the wide thin stainless steel sheet into a steel coil.

[0044] The cooling equipment in step 5) includes a water-blocking mechanism 1, a side-shielding mechanism 2, a laminar flow cooling mechanism 3, a water receiving tank 4, and a straightening mechanism 5; the straightening mechanism 5 is located at one end of the water receiving tank 4, and several side-shielding mechanisms 2 are symmetrically arranged on both sides of the water receiving tank 4, and several laminar flow cooling mechanisms 3 are fixedly connected to the water receiving tank 4 at equal intervals; several water-blocking mechanisms 1 are provided, and are respectively fixedly connected to one side of the laminar flow cooling mechanism 3.

[0045] The water-blocking mechanism 1 includes a water tank 101, connecting columns 1011, guide grooves 1012, a carrier 102, and a water receiver 104. The bottom of the water tank 101 is fixedly connected to the guide groove 1012, and one end of a pair of connecting columns 1011 is fixedly connected to both ends of the water tank 101, and the other end is fixedly connected to the laminar flow cooling mechanism 3. The carrier 102 is located on one side of the water tank 101 and connected to the guide groove 1012, and the water receiver 104 is located above the water tank 101 and slidably connected to the top of the carrier 102.

[0046] The carrier 102 includes a protective box I 1021, a guide box 1022, a sliding rod 1023, a spring 1024, a motor I 1025, a motor II 1026, a gear 1027, a sprocket I 1028, a sprocket II 1029, and a roller 103. One side of the protective box I 1021 is slidably connected to the guide groove 1012. Motors I 1025 and II 1026 are fixedly connected inside the protective box I 1021 via connecting seats, and the output end of motor I 1025 passes through a through hole at the top of the protective box I 1021 and is fixedly connected to the gear 1027. One side of the sprockets I 1028 and II 1029 is connected to the guide groove 1012 via a connecting shaft. The roller 103 in the groove 1012 is fixedly connected. The other side of the sprocket I 1028 is rotatably connected to the protective box I 1021 through the connecting shaft. The other side of the sprocket II 1029 is fixedly connected to the output end of the motor II 1026 through the through hole on the protective box I 1021 through the connecting shaft. The sprocket I 1028 is connected to the sprocket II 1029 through a chain. A pair of guide boxes 1022 are provided, which are fixedly connected to both sides of the protective box I 1021. One end of a pair of sliding rods 1023 is slidably connected to a pair of guide boxes 1022. A pair of springs 1024 are provided, and the springs 1024 are located inside the guide boxes 1022 along the sliding rods 1023.

[0047] The water receiver 104 is provided with a connecting plate I 1041, a telescopic groove 1042, a guide pipe 1043, a sliding plate 1044, a rack 1045, a connecting plate II 1046, a protective box I 1047, an electric pusher cylinder I 1048, a connecting plate III 1049, an electric pusher cylinder II 105, and a baffle 1051. The two ends of the sliding plate 1044 are slidably connected to the guide box 1022 via sliding grooves. The two sides of the telescopic groove 1042 are fixedly connected to a pair of connecting plates I 1041 slidably connected to the sliding plate 1044. One end of each pair of guide pipes 1043 is slidably connected to a pair of connecting plates I 1041. The rack 1045 is located below the telescopic groove 1042 and fixedly connected to the sliding plate 1044. The rack 1045 is connected to the gear... 1027 engagement; a pair of electric push cylinders II 105 are provided, and the cylinder bodies of the pair of electric push cylinders II 105 are fixedly connected to the protective box I 1047 located on the outer wall of the pair of guide pipes 1043 respectively through connecting seats, and the protruding ends pass through the through holes on the protective box I 1047 and are fixedly connected to one end of the connecting plate II 1046; a pair of baffles 1051 are provided, and one end of the pair of baffles 1051 is slidably connected to the pair of guide pipes 1043 respectively, and the other end is fixedly connected to the connecting plate II 1046; a pair of electric push cylinders I 1048 are provided, and the cylinder bodies of the pair of electric push cylinders I 1048 are stacked and fixedly connected to one side of the sliding plate 1044 through connecting seats, and the protruding ends are fixedly connected to the pair of connecting plates I 1041 respectively through connecting plate III 1049.

[0048] The water receiving tank 4 is provided with a squeezing roller 401 at the discharge end, a pinch roller 402 at the feed end, a drain outlet 403 on the side wall, and several transport rollers inside. The correction mechanism 5 is located outside the discharge end of the water receiving tank 4, and the infrared thermal imaging temperature measurement system 7 is located on one side of the pinch roller 402 and is fixedly connected to the water receiving tank 4.

[0049] The edge blocking mechanism 2 includes an electric push cylinder III 201, a water baffle 202, and a rotating roller 2021. There is a pair of electric push cylinders III 201, and the cylinder bodies of the pair of electric push cylinders III 201 are fixedly connected to the water receiving tank 4 through a connecting seat. The extended ends pass through the through holes on the water receiving tank 4 and are fixedly connected to the water baffle 202. There are several rotating rollers 2021, and several rotating rollers 2021 are equidistantly rotatably connected to the inside of the water baffle 202.

[0050] The laminar flow cooling mechanism 3 includes an upper manifold 301, a lower manifold 302, and support columns 303. The two ends of the upper manifold 301 are fixedly connected to the top of a pair of support columns 303, and the lower manifold 302 is located inside the water receiving tank 4 and is fixedly connected to the bottom of a pair of support columns 303. The other ends of a pair of connecting columns 1011 are fixedly connected to a pair of support columns 303.

[0051] The connecting flanges at one end of the upper manifold 301 and the lower manifold 302 are fixedly connected to the cooling equipment through the conveying pipeline.

[0052] The infrared thermal imaging temperature measurement system is a mature temperature measurement system in the existing technology, and will not be described in detail here. Based on the existing PLC controller and the adapted control program and programming logic sequence, the coordinated operation between various components is realized. After the infrared thermal imaging temperature measurement system 7 measures the temperature of the wide-band thin stainless steel plate 6, the wide-band thin stainless steel plate 6 is transported to the laminar flow cooling mechanism 3 below by the pinch roller 402 in the water receiving tank 4. The upper and lower surfaces of the wide-band thin stainless steel plate 6 are sprayed and cooled through the upper manifold 301 and the lower manifold 302. Then, the squeezing roller 401 squeezes out the moisture on the surface of the wide-band thin stainless steel plate 6 and inputs the wide-band thin stainless steel plate 6 into the straightening mechanism 5 for plate shape straightening.

[0053] Based on the measurement data from the infrared thermal imaging temperature measurement system 7, the area with the lowest transverse temperature of the wide-band thin stainless steel plate 6 is located. Then, according to the position of this area, the carrier 102 in the water-blocking mechanism 1 is controlled to move the water receiver 104. The motor I 1025 controls the gear 1027 to mesh with the rack 1045 on the water receiver 104, causing the sliding plate 1044 to drive the connecting plate I 1041 and the telescopic groove 1042 along the guide box 1022 to below a set of water outlets in the upper manifold 301. The cooling water sprayed from these outlets enters between the connecting plate I 1041 and the telescopic groove 1042, and then enters the water tank 101 through the guide pipe 1043. If the area is wide, the electric push cylinder I 1048 can also control the connecting plate III 1049 to drive the connecting plate I 1041 to expand outward along the sliding plate 1044. The cooling water sprayed from the outlets of multiple upper manifolds 301 can enter the connecting plate I 1041 and the expansion groove 1042, thereby reducing the cooling water flow in this area and achieving uniform control of the transverse temperature of the wide-band thin stainless steel 6. Finally, the cooling water in the water tank 101 returns to the cooling equipment through the drain outlet at one end of the water tank 101. At the same time, the electric push cylinder III 201 in the side shielding mechanism 2 is controlled to operate synchronously, and the baffle plate 202 drives the rotating roller 2021 to fit against the side of the wide-band thin stainless steel 6, thereby shielding the edge of the wide-band thin stainless steel 6 and preventing the edge of the wide-band thin stainless steel 6 from cooling down too quickly. At the same time, it can center the wide-band thin stainless steel 6 and prevent it from shifting during movement, ensuring that the area with the lowest transverse temperature of the wide-band thin stainless steel 6 is consistent with the position of the baffle mechanism 1.

[0054] Example 2:

[0055] Unlike Example 1:

[0056] 1) Heating: The heating process is divided into a preheating section, a first heating section, a second heating section, and a soaking section; the temperature of the preheating section is controlled at 750℃; the temperature of the first heating section is controlled at 1050℃; the temperature of the second heating section is controlled at 1180℃; the temperature of the soaking section is controlled at 1200℃; and the furnace pressure is controlled at 25pa.

[0057] Example 3:

[0058] Unlike Example 1:

[0059] 3) Rough rolling: The steel billet is rapidly conveyed to the rough rolling mill via a conveyor device equipped with an insulation cover; during rough rolling, the steel billet is rolled in 7 passes at a rolling speed of 3.5 m / s; the reduction rate is 25% for the first pass, 30% for the second pass, 33% for the third pass, 30% for the fourth pass, 25% for the fifth pass, 20% for the sixth pass, and 15% for the seventh pass.

[0060] Example 4:

[0061] The difference from Example 1 is:

[0062] 1) Heating: The heating process is divided into a preheating section, a first heating section, a second heating section, and a soaking section; the temperature of the preheating section is controlled at 850℃; the temperature of the first heating section is controlled at 1150℃; the temperature of the second heating section is controlled at 1250℃; the temperature of the soaking section is controlled at 1280℃; and the furnace pressure is controlled at 35pa.

[0063] Comparative Example 1: Unlike Example 1, the cooling device in step 5) is replaced with a conventional laminar flow cooling device.

[0064] Comparative Example 2: Unlike Example 1, the correction mechanism 5 used in step 5) is removed.

[0065] Comparative Example 3: The equipment and process used in the invention entitled "A Hot-Rolled Laminar Flow Cooling System" published in CN118060351A were used to cool wide strip stainless steel.

[0066] Experimental samples were taken from Examples 1-4 and Comparative Examples 1-3, and the samples were tested according to the national standard GB / T 4237-2015. The test results are shown in Table 1.

[0067] Table 1. Performance test results for each embodiment and comparative example:

[0068] Tensile strength MPa Elongation strength MPa Elongation after fracture % Appearance quality Example 1 600 290 45 No obvious defects Example 2 550 225 40 No obvious defects Example 3 520 210 35 No obvious defects Example 4 580 270 40 No obvious defects Comparative Example 1 352 145 25 There are many defects such as horizontal bends. Comparative Example 2 410 170 30 Few defects such as horizontal bends Comparative Example 3 515 185 30 Few defects such as horizontal bends

[0069] By analyzing the experimental results of Examples 1-4, the wide-strip stainless steel produced by the process of eliminating transverse fold defects on the surface of hot-rolled wide-strip stainless steel according to the present invention, combined with the cooling equipment, has all mechanical properties that meet the production requirements and the experimental data are stable.

[0070] Comparing the experimental results of Example 1 and Comparative Example 1, during the cooling process of wide-band thin-plate stainless steel, the wide-band thin-plate stainless steel is prone to uneven temperature in the width direction, resulting in uneven microstructure and mechanical properties of stainless steel, ultimately leading to appearance quality problems of wide-band thin-plate stainless steel.

[0071] Comparing the experimental results of Example 1 and Comparative Example 2, after the laminar flow cooling mechanism cools the wide-band stainless steel sheet, a straightening mechanism is set up to straighten the steel sheet shape. This can not only correct defects such as waviness and warping, but also reduce the probability of defects such as transverse folds occurring in subsequent processing.

[0072] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," "top," "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0073] In the description of this invention, the connection methods are divided into fixed connection and movable connection. Fixed connection methods include, but are not limited to, welding and bolting. Movable connection methods include, but are not limited to, sliding connection, rotating connection, and threaded connection. The connection method to achieve the desired effect should be selected according to the application of the solution. Washers are provided in the connection process of the bolts, fixing bolts, studs and nuts. At the same time, the connection of the bolts, fixing bolts, studs and nuts is fixed by thread locking.

[0074] In summary, the electronic or electrical components, including but not limited to motors and electric cylinders, are existing components that were custom-made or purchased. The electrical connections between these components are conventional circuit or electrical connections in the prior art and are not within the scope of protection of this invention. Furthermore, protective covers should be appropriately provided according to the actual installation location, and sealing rings should be appropriately provided at the relative rotational connections to prevent wear or damage to the power system and transmission system from the external environment, thereby further ensuring the normal operation of the power system and transmission system.

[0075] Furthermore, in accordance with the design requirements of this design scheme, appropriate power supply methods should be selected among the electrical components based on the application scenario. Power supply methods include, but are not limited to, power supply through an external power source. Based on the existing PLC controller and the adapted control program and programming logic sequence, the coordinated operation between the components is realized. This control system is not within the scope of protection of this invention.

[0076] The above description is merely an example and illustration of the structure of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the structure of the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A treatment process for eliminating transverse fold defects on the surface of hot-rolled wide stainless steel sheets, characterized in that... The specific process steps are as follows: 1) Heating: The heating process is divided into a preheating section, a first heating section, a second heating section, and a soaking section; the temperature of the preheating section is controlled at 750℃-850℃; the temperature of the first heating section is controlled at 1050℃-1150℃; the temperature of the second heating section is controlled at 1180℃-1250℃; the temperature of the soaking section is controlled at 1200℃-1280℃; and the furnace pressure is controlled at 20-40 Pa. 2) High-pressure water descaling: The oxide scale on the surface of the heated steel billet is removed by high-pressure water at 18-22 MPa to prevent the oxide scale from adversely affecting the surface quality of the steel billet during the rolling process. 3) Rough rolling: The steel billet is rapidly conveyed to the rough rolling mill via a conveyor device equipped with an insulation cover; during rough rolling, the steel billet is rolled in 7 passes at a rolling speed of 2-3.5 m / s; the reduction rate for the first pass is 20%-25%; the reduction rate for the second pass is 25%-30%; the reduction rate for the third pass is 28%-33%; the reduction rate for the fourth pass is 25%-30%; the reduction rate for the fifth pass is 20%-25%; the reduction rate for the sixth pass is 15%-20%; and the reduction rate for the seventh pass is 10%-15%. 4) Finishing rolling: The finishing rolling adopts hot continuous rolling. The steel billet after rough rolling is conveyed into the finishing rolling mechanism to be rolled into wide strip stainless steel. The finishing rolling adopts speed-increasing rolling and pressure AGC is applied. The starting temperature of finishing rolling is set to 1000℃-1050℃; the finishing rolling ending temperature is 850℃-920℃. 5) Laminar flow cooling: The temperature of the wide-band thin stainless steel sheet is detected by an infrared thermal imaging temperature measurement system in the cooling equipment; then, the temperature of the wide-band thin stainless steel sheet is reduced to 550℃-650℃ by the laminar flow cooling mechanism; at the same time, the spray range of the laminar flow cooling mechanism is controlled by a water-blocking mechanism, and the edges of the wide-band thin stainless steel sheet are blocked by an edge-shielding mechanism, thereby reducing the transverse temperature difference of the wide-band thin stainless steel sheet; then, the shape of the wide-band thin stainless steel sheet is corrected by a straightening mechanism. 6) Coiling: Use an underground coiling machine to roll wide thin stainless steel sheets into steel coils.

2. The treatment process for eliminating transverse fold defects on the surface of hot-rolled wide strip stainless steel sheets according to claim 1, characterized in that... The cooling equipment in step 5) includes a water-blocking mechanism, a side-shielding mechanism, a laminar flow cooling mechanism, a water receiving tank, and a straightening mechanism; the straightening mechanism is located at one end of the water receiving tank, and several side-shielding mechanisms are symmetrically arranged on both sides of the water receiving tank, and several laminar flow cooling mechanisms are fixedly connected to the water receiving tank at equal intervals; several water-blocking mechanisms are provided, and each is fixedly connected to one side of the laminar flow cooling mechanism. The water-blocking mechanism includes a water tank, connecting columns, a guide groove, a carrier, and a water receiver; the bottom of the water tank is fixedly connected to the guide groove, and one end of a pair of connecting columns is fixedly connected to both ends of the water tank, and the other end is fixedly connected to the laminar flow cooling mechanism; the carrier is located on one side of the water tank and connected to the guide groove, and the water receiver is located above the water tank and slidably connected to the top of the carrier.

3. The treatment process for eliminating transverse fold defects on the surface of hot-rolled wide strip stainless steel sheets according to claim 2, characterized in that... The carrier includes a protective box I, a guide box, a sliding rod, a spring, a motor I, a motor II, a gear, a sprocket I, a sprocket II, and a roller. One side of the protective box I is slidably connected to a guide groove. Motors I and II are fixedly connected inside the protective box I via connecting seats, and the output end of motor I passes through a through hole in the top of the protective box I and is fixedly connected to the gear. One side of sprocket I and sprocket II is fixedly connected to a roller located in the guide groove via a connecting shaft. The other side of sprocket I is rotatably connected to the protective box I via a connecting shaft, and the other side of sprocket II passes through a through hole in the protective box I via a connecting shaft and is fixedly connected to the output end of motor II. Sprocket I is connected to sprocket II via a chain. A pair of guide boxes are provided, fixedly connected to both sides of the protective box I, and one end of each pair of sliding rods is slidably connected to the pair of guide boxes. A pair of springs are provided, and the springs are located inside the guide boxes along the sliding rods.

4. The treatment process for eliminating transverse fold defects on the surface of hot-rolled wide strip stainless steel sheets according to claim 2, characterized in that... The water receiver includes a connecting plate I, a telescopic groove, a guide pipe, a sliding plate, a rack, a connecting plate II, a protective box I, an electric pusher cylinder I, a connecting plate III, an electric pusher cylinder II, and a baffle. The sliding plate is slidably connected to the guide box at both ends via a sliding groove. The telescopic groove is fixedly connected to a pair of connecting plates I slidably connected to the sliding plate on both sides. One end of each pair of guide pipes is slidably connected to a pair of connecting plates I. The rack is located below the telescopic groove and is fixedly connected to the sliding plate, meshing with a gear. A pair of electric pusher cylinders II are provided, and the cylinder bodies of the pair of electric pusher cylinders II are fixedly connected to the protective box I located on the outer wall of the pair of guide pipes via connecting seats. The protruding ends pass through the through holes on the protective box I and are fixedly connected to one end of the connecting plate II. A pair of baffles are provided, with one end of each baffle slidably connected to a pair of guide pipes and the other end fixedly connected to the connecting plate II. A pair of electric pusher cylinders I are provided, with the cylinder bodies of the pair of electric pusher cylinders I stacked and fixedly connected to one side of the sliding plate via connecting seats. The protruding ends are fixedly connected to a pair of connecting plates I via connecting plate III.

5. The treatment process for eliminating transverse fold defects on the surface of hot-rolled wide strip stainless steel sheets according to claim 2, characterized in that... The water receiving tank is equipped with a squeezing roller at the discharge end, a pinch roller at the feed end, a drain outlet on the side wall, and several transport rollers inside. The correction mechanism is located outside the discharge end of the water receiving tank, and the infrared thermal imaging temperature measurement system is located on one side of the pinch roller and fixedly connected to the water receiving tank.

6. The treatment process for eliminating transverse fold defects on the surface of hot-rolled wide strip stainless steel sheets according to claim 2, characterized in that... The edge shielding mechanism includes an electric push cylinder III, a water baffle, and a rotating roller; there is a pair of electric push cylinders III, and the cylinder bodies of the pair of electric push cylinders III are fixedly connected to the water receiving tank through a connecting seat, and the extended ends pass through the through holes on the water receiving tank and are fixedly connected to the water baffle; there are several rotating rollers, and the several rotating rollers are equidistantly rotatably connected to the inside of the water baffle.

7. The treatment process for eliminating transverse fold defects on the surface of hot-rolled wide strip stainless steel sheets according to claim 2, characterized in that... The laminar flow cooling mechanism includes an upper manifold, a lower manifold, and support columns; both ends of the upper manifold are fixedly connected to the top of a pair of support columns, and the lower manifold is located inside the water receiving tank and fixedly connected to the bottom of a pair of support columns, and the other ends of the pair of connecting columns are fixedly connected to a pair of support columns; the connecting flanges at one end of the upper manifold and the lower manifold are fixedly connected to the cooling equipment through conveying pipes.

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