Production method of ultra-thin 700MPa-grade high-strength container steel plate

Abstract

The invention relates to the technical field of container steel plates, in particular to a production method of an ultra-thin 700MPa-grade high-strength container steel plate. The method comprises the following steps: (1) heating: controlling the heating tapping temperature of a plate blank to be 1260-1280 DEG C, controlling the time of a hot material plate blank in a furnace to be 180-200 minutes, controlling the inter-furnace temperature difference of the plate blank to be within 20 DEG C, and controlling the head and tail temperature difference of the plate blank to be within 20 DEG C; 2) rough rolling: adding dephosphorization water into the rough rolling mill R1 and the rough rolling mill R2 only in the last pass, and controlling the temperature to be 1100-1130 DEG C; (3) finish rolling is conducted, specifically, the guide ruler allowance of the F2 and F3 finish rolling mill is controlled to be 10-20 mm, the guide ruler allowance of the F4 and F5 finish rolling mill is controlled to be 10-30 mm, and the guide ruler allowance of the F6 and F7 finish rolling mill is controlled to be 10-30 mm; the finish rolling temperature of finish rolling is controlled to be 930-960 DEG C; 4) laminar cooling: controlling the head by adopting a high-temperature process, wherein the coiling temperature of 50-100m of the head is 700-730 DEG C; the cooling speed is 50-80 DEG C / s; and 5) coiling: controlling the short stroke of a guide ruler of a coiling machine to be 50-100mm. And the extremely-thin 700 MPa-grade high-strength container steel plate with the thickness of 2.0 mm or below can be successfully produced.

Description

Technical Field

[0001] The invention relates to the technical field of container steel plates, and in particular to a production method of an extremely thin 700MPa grade high-strength container steel plate. Background Art

[0002] Containers are a group of tools that can carry packaged or unpackaged goods for transportation and are easy to load and unload with mechanical equipment. The standardization of container products and the entire transportation system established by them can standardize a huge object with a load of dozens of tons, and gradually realize a logistics system that matches ships, ports, routes, roads, transfer stations, bridges, tunnels, and multimodal transport around the world.

[0003] With the development of the global economy and the growth of international trade, the shipping industry has maintained a rapid growth trend. The demand for container manufacturing has continued to increase. Steel plates for containers are developing in the direction of high strength and light weight. The demand for special containers has gradually increased. The container requires the use of high-strength steel plates with a yield strength of 700MPa. The development of high-strength container steel will directly promote the development of the containerized land-water combined transportation industry and the lightweighting of containers and their carriers, and improve transportation efficiency.

[0004] However, the current production process of ultra-thin 700MPa grade high-strength container steel plates with a thickness of less than 2.0mm has the following difficult-to-solve technical problems: 1) The load is large, and the current of the finishing rolling unit is likely to exceed the upper limit and stop; 2) The strip is extremely thin and has a high alloy content, the plate shape is difficult to control, and the strip is easy to deviate; 3) The temperature fluctuates greatly, and the thickness and width are difficult to guarantee; 4) The strip is extremely thin, and there is a risk of casing when the head runs on the laminar roller, which affects the normal bite of the coiling. As a result, it is impossible to successfully produce ultra-thin 700MPa grade high-strength container steel plates with a thickness of less than 2.0mm. Summary of the invention

[0005] In order to overcome the deficiencies of the prior art, the present invention provides a method for producing an ultra-thin 700MPa grade high-strength container steel plate, which can successfully produce an ultra-thin 700MPa grade high-strength container steel plate with a thickness of less than 2.0mm.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for producing an extremely thin 700MPa grade high-strength container steel plate, wherein the thickness of the steel plate is ≤2mm and the yield strength is above 700MPa.

[0008] The steel plate is composed of the following chemical components in percentage by weight:

[0009] C: 0.06%~0.10%, Si: 0.05%~0.25%, Mn: 1.45%~1.90%, Als: 0.010%~0.055%, Nb: 0.030%~0.075%, Ti: 0.08%~0.15%, P≤0.050%, S≤0.050%, and the balance is Fe and unavoidable impurities.

[0010] The production method specifically comprises the following steps:

[0011] 1) Heating:

[0012] The slab heating tapping temperature is controlled at 1260-1280℃, the hot slab in the furnace time is controlled at 180-200min, the second heating section is controlled at 70-90min, the soaking section is controlled at 70-90min, the slab furnace temperature difference is controlled within 20℃, and the slab head and tail temperature difference is controlled within 20℃;

[0013] 2) Rough rolling:

[0014] For R1 and R2 roughing mills, dephosphorization water is added only in the last pass and controlled at 1100-1130℃;

[0015] 3) Finish rolling:

[0016] The guide gauge allowance of F2 and F3 finishing mills is controlled at 10-20mm, the guide gauge allowance of F4 and F5 finishing mills is controlled at 10-30mm, and the guide gauge allowance of F6 and F7 finishing mills is controlled at 10-30mm;

[0017] The final rolling temperature is controlled at 930-960℃;

[0018] 4) Laminar cooling:

[0019] The head adopts high temperature process control, the coiling temperature of the head 50-100 meters is 700-730℃; the cooling speed is 50-80℃ / s;

[0020] 5) Coiling:

[0021] The short stroke of the coiler guide is controlled at 50-100mm.

[0022] Furthermore, in the step 1), the time of the cold slab in the furnace is controlled at 185 to 205 minutes, the second heating section is controlled at 75 to 95 minutes, and the soaking section is controlled at 75 to 95 minutes.

[0023] Furthermore, in the step 1), the sickle bending trends of the slabs in different heating furnaces are controlled to be consistent.

[0024] Furthermore, in the step 2), the intermediate billet sickle bend is controlled within 15 mm.

[0025] Furthermore, in the step 3), the length of the flying shearing head is 500 mm ≤ 700 mm.

[0026] Furthermore, in the step 3), phosphorus is removed during finishing rolling.

[0027] Furthermore, in the step 3), the cooling water in contact with the steel strip in the finishing mill stand is turned off.

[0028] Furthermore, in the step 3), the convexity is ≤50 μm.

[0029] Furthermore, in the step 3), the absolute value of the wedge is ≤30 μm.

[0030] Compared with the existing method, the beneficial effects of the present invention are:

[0031] The present invention adopts a high temperature and uniform steel burning process, the heating temperature is not less than 1260°C, and the furnace time is not less than 180 minutes, which effectively solves the problem of heavy load in the production process of ultra-thin high-strength steel; the centering ability of the rolling mill is improved by limiting the guide gauge margin, wherein the guide gauge margin of F2 and F3 finishing mills is controlled at 10-20mm, the guide gauge margin of F4 and F5 finishing mills is controlled at 10-30mm, and the guide gauge margin of F6 and F7 finishing mills is controlled at 10-30mm to control the deviation of the strip steel and improve the production rolling stability; by controlling the process temperature and combining the alloy precipitation strengthening mechanism, the RT2 temperature is reasonably controlled at 1100-1130°C, and the final rolling temperature is controlled at 930-960°C, effectively avoiding the precipitation of Nb (C, N) and other precipitation phases during rolling, and achieving good control of width and thickness indicators; adopting high-temperature process control, reducing the amount of laminar cooling water at the head of the strip, reducing the running resistance of the strip, and effectively solving the problem of the strip stacking on the laminar roller, so that the coiler can bite normally. The present invention can successfully produce ultra-thin specifications of 700MPa grade high-strength container steel plates with a thickness of less than 2.0mm. DETAILED DESCRIPTION

[0032] The present invention discloses a method for producing an ultra-thin 700MPa grade high-strength container steel plate. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve it. It is particularly important to point out that all similar substitutions and modifications are obvious to those skilled in the art, and they are all considered to be included in the present invention. The method and application of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0033] A method for producing an extremely thin 700MPa grade high-strength container steel plate, wherein the thickness of the steel plate is ≤2mm and the yield strength is above 700MPa.

[0034] The steel plate is composed of the following chemical components in percentage by weight:

[0035] C: 0.06%~0.10%, Si: 0.05%~0.25%, Mn: 1.45%~1.90%, Als: 0.010%~0.055%, Nb: 0.030%~0.075%, Ti: 0.08%~0.15%, P≤0.050%, S≤0.050%, and the balance is Fe and unavoidable impurities.

[0036] The production method specifically comprises the following steps:

[0037] 1. Heating process

[0038] (1) Considering the high alloy content and high material strength of 700MPa grade high-strength container steel, the slab heating and steel-out temperature is strictly controlled within the range of 1260-1280℃.

[0039] (2) To ensure uniform steel burning, the hot slab is kept in the furnace for 180 to 200 minutes, and the second heating section and soaking section are kept for 70 to 90 minutes. The cold slab is kept for 5 minutes longer on the basis of the above requirements.

[0040] (3) Considering the difficulty of rolling 700MPa grade high-strength container steel with a thickness of less than 2.0mm, the steel burning of slabs in different heating furnaces should be consistent:

[0041] A. The temperature difference between furnaces and the temperature difference between head and tail are controlled within 20℃.

[0042] B. The sickle bending trend control of slabs from different heating furnaces should be consistent.

[0043] 2. Rough rolling process

[0044] (1) To ensure the final rolling temperature and reduce the temperature drop of the intermediate billet:

[0045] A. The intermediate billet during rough rolling is not allowed to be equalized or swung.

[0046] B, R1, and R2 only use the final descaling water.

[0047] (2) To ensure the final rolling temperature, the rough rolling final rolling temperature RT2 is controlled at 1100-1130°C.

[0048] (3) In order to ensure the stability of the head strip threading and tail steel throwing process of finishing rolling, the sickle bend of the intermediate billet is controlled within 15mm.

[0049] 3. Finishing process

[0050] (1) To ensure the stability of steel strip threading and steel throwing for high-strength containers with specifications below 2.0 mm:

[0051] A. 500mm≤flying shear head length≤700mm.

[0052] B. Requirements for spare rolls: Assign rolls according to the target elevation close to zero to ensure the stability of the strip threading process.

[0053] C. Control the excess of the finishing rolling guide to reduce the tendency of the strip to deviate.

[0054] The guide gauge allowance of F2 and F3 finishing mills is controlled within 10-20mm, the guide gauge allowance of F4 and F5 finishing mills is controlled within 10-30mm, and the guide gauge allowance of F6 and F7 finishing mills is controlled within 10-30mm.

[0055] (2) The alloy content of 700MPa grade high-strength container steel is high, and the rolling mill load is large. In particular, the alloy element Nb is a precipitation strengthening element, and its precipitation temperature range is within the control range of finishing rolling. High-strength containers with a thickness of less than 2.0mm are very prone to problems such as strip deviation and steel piling. The cooling water and temperature of the rolling process are controlled:

[0056] A. Descaling water input: Descaling is done on the finishing rolling mill.

[0057] B. FDT temperature is controlled in the range of 930~960℃.

[0058] C. Turn off the cooling water in the finishing mill that is in contact with the strip.

[0059] (3) For high-strength containers with a thickness of less than 2.0 mm, the finished product is thin and the plate shape is difficult to control. The convexity is controlled within the range of ≤50 μm, the absolute value of the wedge is ≤30 μm, and the finished rolled export plate shape is controlled according to the micro-medium wave.

[0060] 4. Laminar cooling

[0061] Since the strip is thin, it is easy to pile up on the laminar roller table:

[0062] A. The head adopts high temperature process control, and the head 50-100 meters is controlled according to the target value +50-80℃ range.

[0063] B. Cooling method adopts Great Wall cooling method.

[0064] 5. Coiling process

[0065] In order to ensure that the extremely thin 700MPa grade high-strength container strip can be normally bitten into the coiler, the short stroke of the coiler guide is controlled within the range of 50 to 100mm.

[0066] Embodiment 1:

[0067] A method for producing an ultra-thin 700MPa grade high-strength container steel plate, wherein the steel plate is composed of the following chemical components in percentage by weight: C: 0.06%, Si: 0.05%, Mn: 1.45%, Als: 0.010%, Nb: 0.030%, Ti: 0.08%, P: 0.030%, S: 0.0150%, and the balance is Fe and unavoidable impurities.

[0068] The production method specifically comprises the following steps:

[0069] 1. Planning

[0070] (1) The plan should control the time when the rolls are changed and all the 700MPA grade high-strength container slabs enter the heating furnace.

[0071] (2) The plan is to start preparing high-strength container steel from the 25th block after the roll change.

[0072] (3) The plan is prepared based on the assumption that the number of 2.0 mm thick blocks in a single cycle shall not exceed 20.

[0073] 2. Heating process

[0074] (1) Control the slab heating and steel-out temperature according to the target value of 1260°C.

[0075] (2) The time for hot slabs in the furnace is guaranteed to be 180 minutes, and the time in the second heating section and the soaking section is guaranteed to be 80 minutes; the time for cold slabs is extended by 5 minutes based on the above requirements.

[0076] (3) The heating of slabs in different heating furnaces should be consistent:

[0077] A. The temperature difference between furnaces and the temperature difference between head and tail are controlled within 15℃.

[0078] B. The sickle bending trend control of slabs from different heating furnaces should be consistent.

[0079] 3. Rough rolling process

[0080] (1) To ensure the final rolling temperature and reduce the temperature drop of the intermediate billet:

[0081] A. The intermediate billet during rough rolling is not allowed to be equalized or swung.

[0082] B, R1, and R2 only use the final descaling water.

[0083] (2) To ensure the final rolling temperature, the rough rolling final rolling temperature RT2 is controlled according to the target value 1110°C.

[0084] (3) In order to ensure the stability of the head strip threading and tail steel throwing process of finishing rolling, the sickle bend of the intermediate billet is controlled within 15mm.

[0085] 4. Finishing process

[0086] (1) To ensure the stability of 2.0mm high-strength container steel strip threading and steel throwing:

[0087] A. The length of the flying shear head is set to 500mm.

[0088] B. Requirements for spare rolls: Assign rolls according to the target elevation close to zero to ensure the stability of the strip threading process.

[0089] C. Control the excess of the finishing rolling guide to reduce the tendency of the strip to deviate.

[0090] The guide ruler allowance of frames F2 and F3 is controlled at 10mm, the guide ruler allowance of F4 is controlled at 15mm, the guide ruler allowance of F5 is controlled at 20mm, the guide ruler allowance of F6 is controlled at 30mm, and the guide ruler allowance of F7 is controlled at 30mm.

[0091] (2) Control the cooling water and temperature during the rolling process:

[0092] A. Descaling water input: Descaling is done on the finishing rolling mill.

[0093] B. The finishing temperature FDT of the finishing rolling is controlled according to the target value of 940°C.

[0094] C. Turn off the cooling water in the finishing mill that is in contact with the strip.

[0095] (3) 2.0mm specification high-strength container plate shape control requirements: the convexity is controlled according to the target value of 45μm, the wedge absolute value is controlled to ≤30μm, and the finished rolling export plate shape is controlled according to the target value of 10I.

[0096] 5. Laminar cooling

[0097] Since the strip is thin, it is easy to pile up on the laminar roller table:

[0098] A. The head adopts high temperature process control, and the head 50 meters follows the target value of +50℃.

[0099] B. Cooling method adopts Great Wall cooling method.

[0100] 6. Coiling process

[0101] In order to ensure that the extremely thin 700MPa grade high-strength container strip can be normally bitten into the coiler, the short stroke of the coiler guide is controlled at 80mm.

[0102] The steel plate of this embodiment has a thickness of 2 mm, a yield strength of 700 MPa, a tensile strength of 820 MPa, and an elongation of 20%. The steel plate of the present invention has excellent comprehensive properties, high strength, high and low temperature toughness, high strain, high crack arrest, and good welding performance, meeting the requirements of high-strength containers.

[0103] Embodiment 2:

[0104] A method for producing an ultra-thin 700MPa grade high-strength container steel plate, wherein the steel plate is composed of the following chemical components in weight percentage: C: 0.07%, Si: 0.06%, Mn: 1.6%, Als: 0.015%, Nb: 0.040%, Ti: 0.10%, P: 0.020%, S: 0.0120%, and the balance is Fe and unavoidable impurities.

[0105] The production method specifically comprises the following steps:

[0106] 1. Planning

[0107] (1) The plan should control the time when the rolls are changed and all the 700MPA grade high-strength container slabs enter the heating furnace.

[0108] (2) The plan is to start preparing high-strength container steel from the 25th block after the roll change.

[0109] (3) The plan is prepared based on the assumption that the number of 2.0 mm thick blocks in a single cycle shall not exceed 20.

[0110] 2. Heating process

[0111] (1) Control the slab heating and steel-out temperature according to the target value of 1270°C.

[0112] (2) The time for hot slabs in the furnace is guaranteed to be 190 minutes, and the time for the second heating section and the soaking section is guaranteed to be 85 minutes; the time for cold slabs is extended by 5 minutes based on the above requirements.

[0113] (3) The heating of slabs in different heating furnaces should be consistent:

[0114] A. The temperature difference between furnaces and the temperature difference between head and tail are controlled within 15℃.

[0115] B. The sickle bending trend control of slabs from different heating furnaces should be consistent.

[0116] 3. Rough rolling process

[0117] (1) To ensure the final rolling temperature and reduce the temperature drop of the intermediate billet:

[0118] A. The intermediate billet during rough rolling is not allowed to be equalized or swung.

[0119] B, R1, and R2 only use the final descaling water.

[0120] (2) To ensure the final rolling temperature, the rough rolling final rolling temperature RT2 is controlled according to the target value of 1115°C.

[0121] (3) In order to ensure the stability of the head strip threading and tail steel throwing process of finishing rolling, the sickle bend of the intermediate billet is controlled within 15mm.

[0122] 4. Finishing process

[0123] (1) To ensure the stability of 1.8mm high-strength container steel strip threading and steel throwing:

[0124] A. The length of the flying shear head is set to 600mm.

[0125] B. Requirements for spare rolls: Assign rolls according to the target elevation close to zero to ensure the stability of the strip threading process.

[0126] C. Control the excess of the finishing rolling guide to reduce the tendency of the strip to deviate.

[0127] The guide ruler allowance of frames F2 and F3 is controlled at 8mm, the guide ruler allowance of F4 is controlled at 12mm, the guide ruler allowance of F5 is controlled at 15mm, the guide ruler allowance of F6 is controlled at 25mm, and the guide ruler allowance of F7 is controlled at 25mm.

[0128] (2) Control the cooling water and temperature during the rolling process:

[0129] A. Descaling water input: Descaling is done on the finishing rolling mill.

[0130] B. The finishing temperature FDT of the finishing rolling is controlled according to the target value of 945°C.

[0131] C. Turn off the cooling water in the finishing mill that is in contact with the strip.

[0132] (3) 2.0mm specification high-strength container plate shape control requirements: the convexity is controlled according to the target value of 40μm, the wedge absolute value is controlled to ≤25μm, and the finished rolling export plate shape is controlled according to the target value of 9I.

[0133] 5. Laminar cooling

[0134] Since the strip is thin, it is easy to pile up on the laminar roller table:

[0135] A. The head adopts high temperature process control, and the head 65 meters is controlled according to the target value +65℃.

[0136] B. Cooling method adopts Great Wall cooling method.

[0137] 6. Coiling process

[0138] In order to ensure that the extremely thin 700MPa grade high-strength container strip can be normally bitten into the coiler, the short stroke of the coiler guide is controlled at 80mm.

[0139] The steel plate of this embodiment has a thickness of 2 mm, a yield strength of 760 MPa, a tensile strength of 850 MPa, and an elongation of 21%. The steel plate of the present invention has excellent comprehensive properties, high strength, high and low temperature toughness, high strain, high crack arrest, and good welding performance, meeting the requirements of high-strength containers.

[0140] Embodiment 3:

[0141] A method for producing an ultra-thin 700MPa grade high-strength container steel plate, wherein the steel plate is composed of the following chemical components in percentage by weight: C: 0.08%, Si: 0.08%, Mn: 1.70%, Als: 0.025%, Nb: 0.055%, Ti: 0.080%, P≤0.015%, S≤0.010%, and the balance is Fe and unavoidable impurities.

[0142] The production method specifically comprises the following steps:

[0143] 1. Planning

[0144] (1) The plan should control the time when the rolls are changed and all the 700MPA grade high-strength container slabs enter the heating furnace.

[0145] (2) The plan is to start preparing high-strength container steel from the 25th block after the roll change.

[0146] (3) The plan is prepared based on the assumption that the number of 2.0 mm thick blocks in a single cycle shall not exceed 20.

[0147] 2. Heating process

[0148] (1) Control the slab heating and steel-out temperature according to the target value of 1280°C.

[0149] (2) The hot slabs must be in the furnace for 200 minutes, and the second heating section and soaking section must be 90 minutes; the cold slabs must be extended by 5 minutes based on the above requirements.

[0150] (3) The heating of slabs in different heating furnaces should be consistent:

[0151] A. The temperature difference between furnaces and the temperature difference between head and tail are controlled within 15℃.

[0152] B. The sickle bending trend control of slabs from different heating furnaces should be consistent.

[0153] 3. Rough rolling process

[0154] (1) To ensure the final rolling temperature and reduce the temperature drop of the intermediate billet:

[0155] A. The intermediate billet during rough rolling is not allowed to be equalized or swung.

[0156] B, R1, and R2 only use the final descaling water.

[0157] (2) To ensure the final rolling temperature, the rough rolling final rolling temperature RT2 is controlled according to the target value of 1125°C.

[0158] (3) In order to ensure the stability of the head strip threading and tail steel throwing process of finishing rolling, the sickle bend of the intermediate billet is controlled within 15mm.

[0159] 4. Finishing process

[0160] (1) To ensure the stability of 2.0mm high-strength container steel strip threading and steel throwing:

[0161] A. The length of the flying shear head is set to 700mm.

[0162] B. Requirements for spare rolls: Assign rolls according to the target elevation close to zero to ensure the stability of the strip threading process.

[0163] C. Control the excess of the finishing rolling guide to reduce the tendency of the strip to deviate.

[0164] The guide ruler allowance of frames F2 and F3 is controlled at 5mm, the guide ruler allowance of F4 is controlled at 10mm, the guide ruler allowance of F5 is controlled at 15mm, the guide ruler allowance of F6 is controlled at 20mm, and the guide ruler allowance of F7 is controlled at 20mm.

[0165] (2) Control the cooling water and temperature during the rolling process:

[0166] A. Descaling water input: Descaling is done on the finishing rolling mill.

[0167] B. The finishing temperature FDT of the finishing rolling is controlled according to the target value of 960°C.

[0168] C. Turn off the cooling water in the finishing mill that is in contact with the strip.

[0169] (3) 2.0mm specification high-strength container plate shape control requirements: the convexity is controlled according to the target value of 35μm, the wedge absolute value is controlled to ≤20μm, and the finished rolling export plate shape is controlled according to the target value of 6I.

[0170] 5. Laminar cooling

[0171] Since the strip is thin, it is easy to pile up on the laminar roller table:

[0172] A. The head adopts high temperature process control, and the head 80 meters is controlled according to the target value +80℃.

[0173] B. Cooling method adopts Great Wall cooling method.

[0174] 6. Coiling process

[0175] In order to ensure that the extremely thin 700MPa grade high-strength container strip can be normally bitten into the coiler, the short stroke of the coiler guide is controlled at 80mm.

[0176] The steel plate of this embodiment has a thickness of 2 mm, a yield strength of 780 MPa, a tensile strength of 890 MPa, and an elongation of 23%. The steel plate of the present invention has excellent comprehensive properties, including high strength, high and low temperature toughness, high strain, high crack arrest, and good welding performance, meeting the requirements of high-strength containers.

[0177] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for producing an ultra-thin 700MPa grade high-strength container steel plate, characterized in that: The steel plate has a thickness of ≤2 mm and a yield strength of 700 MPa or more. The production method specifically comprises the following steps: 1) Heating: The slab heating tapping temperature is controlled at 1260-1280℃, the hot slab in the furnace time is controlled at 180-200min, the second heating section of the hot slab is controlled at 70-90min, the hot slab soaking section is controlled at 70-90min, the slab furnace temperature difference is controlled within 20℃, and the slab head and tail temperature difference is controlled within 20℃; 2) Rough rolling: For R1 and R2 roughing mills, dephosphorization water is added only in the last pass, and the roughing and final rolling temperature is controlled at 1100-1130℃; 3) Finish rolling: The guide gauge allowance of F2 and F3 finishing mills is controlled at 10-20mm, the guide gauge allowance of F4 and F5 finishing mills is controlled at 10-30mm, and the guide gauge allowance of F6 and F7 finishing mills is controlled at 10-30mm; The final rolling temperature is controlled at 930-960℃; 4) Laminar cooling: The head adopts high temperature process control, and the coiling temperature of the first 50-100 meters is 700-730℃; Cooling rate 50~80℃ / s; 5) Coiling: The short stroke of the coiler guide is controlled at 50-100mm.

2. The method for producing an ultra-thin 700MPa grade high-strength container steel plate according to claim 1, characterized in that: In the step 1), the time of the cold slab in the furnace is controlled at 185 to 205 minutes, the second heating section of the cold slab is controlled at 75 to 95 minutes, and the soaking section of the cold slab is controlled at 75 to 95 minutes.

3. The method for producing an ultra-thin 700MPa grade high-strength container steel plate according to claim 1, characterized in that: In the step 1), the sickle bending trends of the slabs in different heating furnaces are controlled to be consistent.

4. The method for producing an ultra-thin 700MPa grade high-strength container steel plate according to claim 1, characterized in that: In the step 2), the intermediate billet sickle bend is controlled within 15 mm.

5. The method for producing an ultra-thin 700MPa grade high-strength container steel plate according to claim 1, characterized in that: In the step 3), the length of the flying shearing head is 500 mm ≤ ≤ 700 mm.

6. The method for producing an ultra-thin 700MPa grade high-strength container steel plate according to claim 1, characterized in that: In the step 3), the finishing rolling is performed to remove phosphorus.

7. The method for producing an ultra-thin 700MPa grade high-strength container steel plate according to claim 1, characterized in that: In the step 3), the cooling water in contact with the steel strip in the finishing mill stand is turned off.

8. The method for producing an ultra-thin 700MPa grade high-strength container steel plate according to claim 1, characterized in that: In the step 3), the convexity is ≤50 μm.

9. The method for producing an ultra-thin 700MPa grade high-strength container steel plate according to claim 1, characterized in that: In the step 3), the absolute value of the wedge is ≤30 μm.

10. The method for producing an ultra-thin 700MPa grade high-strength container steel plate according to claim 1, characterized in that: The steel plate is composed of the following chemical components in percentage by weight: C: 0.06%~0.10%, Si: 0.05%~0.25%, Mn: 1.45%~1.90%, Als: 0.010%~0.055%, Nb: 0.030%~0.075%, Ti: 0.08%~0.15%, P≤0.050%, S≤0.050%, and the balance is Fe and unavoidable impurities.