CN113235008A - Ultra-long thin-specification structural steel plate with length being more than or equal to 50m and rolling method thereof - Google Patents
Ultra-long thin-specification structural steel plate with length being more than or equal to 50m and rolling method thereof Download PDFInfo
- Publication number
- CN113235008A CN113235008A CN202110543376.7A CN202110543376A CN113235008A CN 113235008 A CN113235008 A CN 113235008A CN 202110543376 A CN202110543376 A CN 202110543376A CN 113235008 A CN113235008 A CN 113235008A
- Authority
- CN
- China
- Prior art keywords
- steel plate
- rolling
- cooling
- temperature
- equal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
- B21B45/0203—Cooling
- B21B45/0209—Cooling devices, e.g. using gaseous coolants
- B21B45/0215—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes
- B21B45/0218—Cooling devices, e.g. using gaseous coolants using liquid coolants, e.g. for sections, for tubes for strips, sheets, or plates
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
- B21B2001/225—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length by hot-rolling
Abstract
The invention discloses an ultra-long thin structural steel plate with the length being more than or equal to 50m and a rolling method thereof, wherein the steel plate comprises the following chemical components in percentage by mass: c: 0.05-0.16%, Mn: 0.6-2.0%, Si: 0.10-0.80%, P is less than or equal to 0.020%, S is less than or equal to 0.003%, Nb: 0.000 to 0.040%, Als: 0.010-0.045%, Ti: 0.050-0.050% and the balance of Fe and inevitable impurity elements; the production method of the steel plate comprises the steps of casting blank heating, controlled rolling, pre-cooling and ACC cooling; the yield strength difference between head, middle and tail of the steel plate prepared by the invention at normal temperature is less than or equal to 30MPa, the tensile strength difference is less than or equal to 20MPa, the elongation is more than or equal to 20 percent, the transverse and longitudinal impact energy at minus 40 ℃ is more than or equal to 120J, the obtained tissue is uniform, and the grain size difference is within 0.5 grade; has high strength, high toughness and high longitudinal uniformity, and can meet the manufacturing requirements of structures such as bridges, buildings, ocean platforms, shipbuilding and the like.
Description
Technical Field
The invention relates to the technical field of manufacturing of super-long thin-specification steel plates, in particular to a super-long thin-specification structural steel plate with the length of more than or equal to 50m and a rolling method thereof.
Background
With the continuous acceleration of the industrialized process in China, the continuous increase of the span of a bridge, the large-scale construction of buildings and ocean platforms, steel structure manufacturing factories require increasingly obvious trend of increasing the width and the length of a steel plate for reducing welding, but the increase of the length of the steel plate is a great test on how to ensure the consistency of the surface and the performance of the steel plate for steel rolling enterprises, and particularly when the medium plate enterprises produce ultra-long steel plates with the thickness of less than or equal to 20mm, the poor uniformity is the most prominent problem in each domestic steel factory. However, the steel plate needs to be opened and flattened during plate rolling, and the steel plate has stress, so that the manufacturing plant has higher cost and mass pressure.
Before the invention, related inventions are also available at home and abroad. For example, Chinese patent CN 109092893A discloses a '60 m super-long steel plate production process' for producing a thin steel plate with the thickness of 7.5-12.5 mm, wherein bottom roll cooling water is adjusted to be small before finish rolling, high-pressure water descaling in the rolling process is reduced, and the influence of water on the uniformity of the steel plate in the rolling process is mainly considered. However, the influence of accelerated cooling of the rolled steel plate on the uniformity of the thin gauge is not considered, a controlled cooling mode after rolling is not adopted, and only steel with the strength level less than 420MPa can be obtained, so that the manufacturing method of the steel plate is not widely applicable to the production of high-strength structural steel plates.
Chinese patent CN 110004359A discloses a high-uniformity longitudinal and transverse toughness wide steel plate and a TMCP process production method thereof, wherein a TMCP production process is adopted to obtain a wide steel plate with the thick specification yield strength of 400-600 MPa, a two-stage rolling control mode is also adopted for rolling, the temperature and the total compression ratio of each rolling stage are controlled, the interval time of a rolling gap is ensured under low speed and high pressure in a rough rolling stage, and the controlled cooling is adopted after rolling, but the invention aims to obtain the steel plate with the thick specification of 70-90 mm. The manufacturing method thereof produces steel plates having different sizes from those of the present invention.
Chinese patent CN 110735085A discloses a method for manufacturing a thin Q345qE/Q370qE steel plate. The method mainly comprises the steps of rolling an original plate blank to a transition blank of 80-100 mm in a cogging rolling mode, carrying out controlled rolling in a secondary heating rolling process, and naturally cooling after rolling to obtain the bridge steel plate with the thickness of less than or equal to 10 mm. The method ensures the uniformity of the steel plate by cogging and rolling twice, reduces the time of the rolling process, ensures the uniformity of the steel plate in a mode of not cooling water after the rolling, and substantially ensures the uniformity of thin specifications by reducing the length of the steel plate, which is completely opposite to the method of the invention.
Chinese patent CN 108624818A discloses a 400-500 MPa-grade high-uniform-elongation hot continuous rolling steel plate and a manufacturing method thereof, which obtains a thin steel plate with the thickness less than or equal to 12mm by a hot continuous rolling mode, and is obviously different from the manufacturing method of the invention.
Although the above patents solve the problem of the uniformity of the overall performance of some steel plates, no solution is provided for the ultra-long and thin steel plates with high strength grade structure, so that the development of a rolling method for the ultra-long and thin steel plates to ensure the uniformity of the performance is a problem to be solved urgently in the industry.
Disclosure of Invention
The invention aims to provide an ultra-long thin structural steel plate with the length of more than or equal to 50m and a rolling method thereof, wherein the yield strength difference between the head, the middle and the tail of the steel plate at normal temperature is less than or equal to 30MPa, the tensile strength difference is less than or equal to 20MPa, the elongation is more than or equal to 20 percent, the transverse and longitudinal impact energy at minus 40 ℃ is more than or equal to 120J, the obtained tissue is uniform, the grain size difference is within 0.5 grade, and the ultra-long thin structural steel plate has high strength, high toughness and high longitudinal uniformity and can meet the manufacturing requirements of structures such as bridges, buildings, ocean platforms, shipbuilding and the like.
The invention relates to an ultra-long thin specification structural steel plate with the length being more than or equal to 50m, which comprises the following chemical components in percentage by mass: c: 0.05-0.16%, Mn: 0.6-2.0%, Si: 0.10-0.80%, P is less than or equal to 0.020%, S is less than or equal to 0.003%, Nb: 0.000 to 0.040%, Als: 0.010-0.045%, Ti: 0.050-0.050% and the balance of Fe and inevitable impurity elements;
the rolling method of the steel plate comprises the following steps:
(1) heating a casting blank: pouring to obtain a continuous casting slab with the thickness of 160-250 mm, heating the continuous casting slab, and controlling the temperature of a soaking section to be 1150-1250 ℃ and the heating rate to be 8-11 min/cm;
(2) controlling rolling: in the rough rolling stage, high temperature and high pressure are adopted, the billet is taken out of the furnace and then is descaled, the rolling is started, the initial rolling temperature is 1130-1170 ℃, the final rolling temperature is controlled to be more than 1000 ℃, and the thickness of the rolling stop is 2.5-3.5 times of the thickness of a finished product; during finish rolling, cooling water for a roller way and a roller body of a rolling mill is reduced, the opening degree of the cooling water is controlled according to 20-30%, the start rolling temperature of the finish rolling is 880-1000 ℃, high-pressure water is not pumped in the rolling process, the rolling process is not stopped, the finish rolling temperature of the finish rolling is controlled to be 830-890 ℃, and the length of a rolled steel plate is more than or equal to 50 m;
(3) pre-cooling: pre-straightening the rolled steel plate to ensure the steel plate to be straight, then entering a pre-cooling device, starting cooling water after the steel plate passes through 1m, keeping the cooling speed at 5 ℃/s, then continuously reducing the water quantity, and closing the cooling water at a position 2m away from the tail part of the steel plate so as to control the temperature before ACC to be 710-720 ℃;
(4) ACC cooling: and carrying out ACC water cooling on the steel plate, keeping the cooling speed unchanged, keeping the final cooling temperature at 400-600 ℃, and cooling the steel plate to room temperature in the air after leveling.
The yield strength difference between the head, the middle and the tail of the steel plate at normal temperature is less than or equal to 30MPa, the tensile strength difference is less than or equal to 20MPa, the elongation is more than or equal to 20 percent, the transverse and longitudinal impact energy at minus 40 ℃ is more than or equal to 120J, the obtained structure is uniform, and the grain size difference is within 0.5 grade.
The thickness of the steel plate is 6-20 mm.
The invention relates to a rolling method of an ultra-long thin specification structural steel plate with the length of more than or equal to 50m, which comprises the steps of casting blank heating, controlled rolling, pre-cooling and ACC cooling, wherein the rolling method comprises the following steps:
(1) heating a casting blank: pouring to obtain a continuous casting slab with the thickness of 160-250 mm, heating the continuous casting slab, and controlling the temperature of a soaking section to be 1150-1250 ℃ and the heating rate to be 8-11 min/cm;
(2) controlling rolling: in the rough rolling stage, high temperature and high pressure are adopted, the billet is taken out of the furnace and then is descaled, the rolling is started, the initial rolling temperature is 1130-1170 ℃, the final rolling temperature is controlled to be more than 1000 ℃, and the thickness of the rolling stop is 2.5-3.5 times of the thickness of a finished product; during finish rolling, cooling water for a roller way and a roller body of a rolling mill is reduced, the opening degree of the cooling water is controlled according to 20-30%, the start rolling temperature of the finish rolling is 880-1000 ℃, high-pressure water is not pumped in the rolling process, the rolling process is not stopped, the finish rolling temperature of the finish rolling is controlled to be 830-890 ℃, and the length of a rolled steel plate is more than or equal to 50 m;
(3) pre-cooling: pre-straightening the rolled steel plate to ensure the steel plate to be straight, then entering a pre-cooling device, starting cooling water after the steel plate passes through 1m, keeping the cooling speed at 5 ℃/s, then continuously reducing the water quantity, and closing the cooling water at a position 2m away from the tail part of the steel plate so as to control the temperature before ACC to be 710-720 ℃;
(4) ACC cooling: and carrying out ACC water cooling on the steel plate, keeping the cooling speed unchanged, keeping the final cooling temperature at 400-600 ℃, and cooling the steel plate to room temperature in the air after leveling.
The rolling process of the invention is designed for the following reasons:
in the technical scheme provided by the invention, the pre-cooling method of changing the cooling speed is added before ACC (accelerated cooling) by optimizing the rolling process, so that the longitudinal temperature uniformity of the ultra-long steel plate is achieved.
The heating process is set below 1250 ℃, so as to prevent austenite grains from seriously influencing toughness after coarsening, ensure enough soaking time and fully and uniformly diffuse and homogenize elements of steel grades and the like.
In the rough rolling stage, the rolling force is ensured to be transmitted to the center through the high pressure, so that the austenite is fully recovered after recrystallization, and the austenite grains are ensured to be uniformly refined; and cooling water for a roller way and a roller body of the rolling mill is reduced in the finish rolling stage, the opening degree of the cooling water is controlled according to 20-30%, and high-pressure water is not applied in the rolling process so as to reduce the temperature difference between the upper surface and the lower surface of the steel plate and between the upper surface and the lower surface of the steel plate in the longitudinal direction as far as possible. The rolling process is not stopped, so that the temperature nonuniformity of different positions of the steel plate caused by heat dissipation is reduced, and the crystal grains are accumulated due to rolling deformation.
The method has the advantages that pre-straightening is carried out after the steel plate is rolled, the steel plate is guaranteed to be straight, then the steel plate enters the pre-cooling device, the core point is the core point in the method, the temperature uniformity is guaranteed to roll the ultra-long thin steel, in the existing production practice, the rolling speed is obviously higher than the steel plate advancing speed in the ACC water cooling process, the temperature drop of the thin steel plate is very large, and the temperature difference entering the ACC limits the production of the existing ultra-long single-rolled steel plate. Therefore, the pre-cooling method is added before ACC, cooling water is started after the steel plate with the temperature before entering the rapid cooling passes through 1m, the cooling speed is 5 ℃/s, then the water quantity is continuously reduced, and the cooling water is stopped at a position 2m away from the tail of the steel plate, so that the temperature before ACC is 710-720 ℃. The steel plate is subjected to ACC water cooling, the cooling speed is kept unchanged, and the uniformity of the thin steel plate is further improved.
The thickness of the steel plate finished product prepared by the method is 6-20 mm, the head-to-tail yield strength difference at normal temperature is less than or equal to 30MPa, the tensile strength difference is less than or equal to 20MPa, the elongation is more than or equal to 20%, the transverse and longitudinal impact energy at-40 ℃ is more than or equal to 120J, the obtained tissue is uniform, the grain size difference is within 0.5 grade, and the steel plate finished product has high strength, high toughness and high longitudinal uniformity and can meet the manufacturing requirements of structures such as bridges, buildings, ocean platforms, shipbuilding and the like.
Drawings
FIG. 1 is a photograph of the metallographic structure of the head of a steel sheet obtained in example 2 of the present invention, which is enlarged to 100 μm and 20 μm, respectively;
FIG. 2 is a middle metallographic structure photograph of a steel sheet obtained in example 2 of the present invention, in which the metallographic structure photographs were enlarged to 100 μm and 20 μm, respectively;
FIG. 3 is a photograph showing the metallographic structure of the tail part of the steel sheet according to example 2 of the present invention, wherein the metallographic structure is enlarged to 100 μm and 20 μm, respectively.
Detailed Description
In order to better explain the technical solution of the present invention, the technical solution of the present invention is further described below with reference to specific examples, which are only exemplary to illustrate the technical solution of the present invention and do not limit the present invention in any way.
Table 1 below is a table of values of chemical components of the steel sheets according to the embodiments of the present invention;
the following table 2 shows the mechanical property test results of the steel sheets according to the examples of the present invention.
The invention relates to an ultra-long thin specification structural steel plate with the length being more than or equal to 50m, which comprises the following chemical components in percentage by mass: c: 0.05-0.16%, Mn: 0.6-2.0%, Si: 0.10-0.80%, P is less than or equal to 0.020%, S is less than or equal to 0.003%, Nb: 0.000 to 0.040%, Als: 0.010-0.045%, Ti: 0.050-0.050% and the balance of Fe and inevitable impurity elements;
wherein the thickness of the products of examples 1-5 are 20mm, 16mm, 12mm, 8mm, 6mm, respectively.
Table 1 tabulated (wt,%) chemical composition values for various examples of the invention
Example 1
The chemical components and the mass percentage contents of the ultra-long thin gauge structural steel plate with the length of more than or equal to 50m in the embodiment are shown in table 1.
The rolling method of the steel plate comprises the following steps:
(1) heating a casting blank: the size of the selected continuous casting slab is 250 multiplied by 2000 mm; heating the continuous casting plate blank, and controlling the temperature of a soaking section to be 1240 ℃ and the heating rate to be 10.5 min/cm;
(2) controlling rolling: rolling a steel plate by adopting a controlled rolling process of two stages of rough rolling and finish rolling, wherein the rough rolling stage adopts high temperature and high pressure, the steel billet is taken out of a furnace and then descaled, and then the steel billet starts to be rolled, the initial rolling temperature is 1165 ℃, the final rolling temperature is 1102 ℃, and the rolling stop thickness is 52 mm; during finish rolling, cooling water of a roller way and a roller body of a rolling mill is reduced, the opening degree of the cooling water is 27%, the start rolling temperature of the finish rolling is 892 ℃, high-pressure water is not pumped during the rolling process, the rolling process is not stopped, the finish rolling temperature of the finish rolling is 833 ℃, and the length of a rolled steel plate is 55 m;
(3) pre-cooling: pre-straightening the rolled steel plate to ensure that the steel plate is straight, then entering a pre-cooling device, starting cooling water after the steel plate passes through 1m, keeping the cooling speed at 5 ℃/s, then continuously reducing the water quantity, closing the cooling water at a position 2m away from the tail of the steel plate, and keeping the temperature before ACC entering to be 713-716 ℃;
(4) ACC cooling: carrying out ACC water cooling on the steel plate, keeping the cooling speed unchanged, keeping the final cooling temperature at 520 ℃, and cooling the steel plate in the air to room temperature after leveling;
the steel plate manufactured by adopting the element component content and the processing steps has the thickness specification of 20mm multiplied by 2150mm, and the mechanical properties of the steel plate are shown in Table 2.
Example 2
The chemical components and the mass percentage contents of the ultra-long thin gauge structural steel plate with the length of more than or equal to 50m in the embodiment are shown in table 1.
The rolling method of the steel plate comprises the following steps:
(1) heating a casting blank: the size of the selected continuous casting slab is 200 multiplied by 2000 mm; heating the continuous casting plate blank, and controlling the temperature of a soaking section to be 1175 ℃ and the heating rate to be 9.8 min/cm;
(2) controlling rolling: rolling a steel plate by adopting a controlled rolling process of two stages of rough rolling and finish rolling, wherein the rough rolling stage adopts high temperature and high pressure, the steel billet is taken out of a furnace and then descaled, and then the steel billet starts to be rolled, the initial rolling temperature is 1147 ℃, the final rolling temperature is 1080 ℃, and the rolling stop thickness is 45 mm; during finish rolling, cooling water for a roller way and a roller body of a rolling mill is reduced, the opening degree of the cooling water is controlled to be 21%, the start rolling temperature of the finish rolling is 972 ℃, high-pressure water is not applied in the rolling process, the rolling process is not stopped, the finish rolling temperature of the finish rolling is 856 ℃, and the length of a rolled steel plate is 62 m;
(3) pre-cooling: pre-straightening the rolled steel plate to ensure that the steel plate is straight, then entering a pre-cooling device, starting cooling water after the steel plate passes through 1m, keeping the cooling speed at 5 ℃/s, then continuously reducing the water quantity, closing the cooling water at a position 2m away from the tail of the steel plate, and keeping the temperature of the steel plate before ACC entering to be 710-713 ℃;
(4) ACC cooling: and performing ACC water cooling on the steel plate, keeping the cooling speed unchanged, keeping the final cooling temperature at 592 ℃, and cooling the steel plate in the air to room temperature after leveling.
The steel plate manufactured by adopting the element component contents and the processing steps has the thickness specification of 16mm multiplied by 2220mm, the mechanical properties of the steel plate are shown in table 2, the metallographic structure of the steel plate is shown in figures 1, 2 and 3, the structure is mainly ferrite and pearlite, a small amount of bainite exists in the metallographic structure, the crystal grains are uniform, and the grain sizes of the head part, the middle part and the tail part of the steel plate are all 8 grades.
Example 3
The chemical components and the mass percentage contents of the ultra-long thin gauge structural steel plate with the length of more than or equal to 50m in the embodiment are shown in table 1.
The rolling method of the steel plate comprises the following steps:
(1) heating a casting blank: the size of the selected continuous casting slab is 230 multiplied by 1850 mm; heating the continuous casting plate blank, and controlling the temperature of a soaking section to be 1192 ℃ and the heating rate to be 8.5 min/cm;
(2) controlling rolling: rolling a steel plate by adopting a controlled rolling process of two stages of rough rolling and finish rolling, wherein the rough rolling stage adopts high temperature and high pressure, the steel billet is taken out of a furnace and then descaled, and then the steel billet starts to be rolled, the initial rolling temperature is 1133 ℃, the final rolling temperature is controlled to 1042 ℃, and the rolling stop thickness is 35 mm; during finish rolling, cooling water for a roller way and a roller body of a rolling mill is reduced, the opening degree of the cooling water is 27%, the start rolling temperature of the finish rolling is 996 ℃, high-pressure water is not applied during the rolling process, the rolling process is not stopped, the finish rolling temperature of the finish rolling is controlled to be 885 ℃, and the length of a rolled steel plate is 54 m;
(3) pre-cooling: pre-straightening is carried out after the steel plate is rolled, the steel plate is ensured to be straight, then the steel plate enters a pre-cooling device, cooling water is started after the steel plate passes through 1m, the cooling speed is 5 ℃/s, then the water quantity is continuously reduced, the cooling water is closed at a position 2m away from the tail part of the steel plate, and the temperature before ACC entering is 715-717 ℃;
(4) ACC cooling: and performing ACC water cooling on the steel plate, keeping the cooling speed unchanged, keeping the final cooling temperature to be 554 ℃, and cooling the steel plate in the air to room temperature after leveling.
The steel plate manufactured by adopting the element component contents and the processing steps has the thickness specification of 12mm multiplied by 2750mm, and the mechanical properties of the steel plate are shown in table 2.
Example 4
The chemical components and the mass percentage contents of the ultra-long thin gauge structural steel plate with the length of more than or equal to 50m in the embodiment are shown in table 1.
The rolling method of the steel plate comprises the following steps:
(1) heating a casting blank: the size of the selected continuous casting slab is 180 multiplied by 2150 mm; heating the continuous casting plate blank, and controlling the temperature of a soaking section to 1211 ℃ and the heating rate to be 8.9 min/cm;
(2) controlling rolling: rolling a steel plate by adopting a controlled rolling process of two stages of rough rolling and finish rolling, wherein the rough rolling stage adopts high temperature and high pressure, the steel billet is taken out of a furnace and then descaled, and then the steel billet starts to be rolled, the initial rolling temperature is 1165 ℃, the final rolling temperature is 1140 ℃, and the rolling stop thickness is 26mm of the thickness of a finished product; and during finish rolling, cooling water for a roller way and a roller body of a rolling mill is reduced, the opening degree of the cooling water is controlled to be 20%, the start rolling temperature of the finish rolling is 990 ℃, high-pressure water is not applied in the rolling process, the rolling process is not stopped, the finish rolling temperature of the finish rolling is controlled to be 842 ℃, and the length of a rolled steel plate is 56 m.
(3) Pre-cooling: pre-straightening the rolled steel plate to ensure the steel plate to be straight, then enabling the steel plate to enter a pre-cooling device, starting cooling water after the steel plate passes through 1m, keeping the cooling speed at 5 ℃/s, then continuously reducing the water quantity, closing the cooling water at a position 2m away from the tail part of the steel plate, and enabling the temperature to be 712-716 ℃ when ACC is fed;
(4) ACC cooling: and (3) carrying out ACC water cooling on the steel plate, keeping the cooling speed unchanged, keeping the final cooling temperature to be 485 ℃, and cooling the steel plate in the air to room temperature after leveling.
The steel plate manufactured by adopting the element component contents and the processing steps has the thickness specification of 8mm multiplied by 2880mm, and the mechanical properties of the steel plate are shown in table 2.
Example 5
The chemical components and the mass percentage contents of the ultra-long thin gauge structural steel plate with the length of more than or equal to 50m in the embodiment are shown in table 1.
The rolling method of the steel plate comprises the following steps:
(1) heating a casting blank: the size of the selected continuous casting plate blank is 160 x 1900 mm; heating the continuous casting plate blank, and controlling the temperature of a soaking section to be 1155 ℃ and the heating rate to be 8 min/cm;
(3) controlling rolling: rolling a steel plate by adopting a controlled rolling process of two stages of rough rolling and finish rolling, wherein the rough rolling stage adopts high temperature and high pressure, the steel billet is taken out of a furnace and then descaled, and then the steel billet starts to be rolled, the initial rolling temperature is 1135 ℃, the final rolling temperature is 1010 ℃, and the rolling stop thickness is 21 mm; during finish rolling, cooling water for a roller way and a roller body of a rolling mill is reduced, the opening degree of the cooling water is controlled to be 24%, the start rolling temperature of the finish rolling is 1000 ℃, high-pressure water is not applied in the rolling process, the rolling process is not stopped, the finish rolling temperature of the finish rolling is controlled to be 826 ℃, and the length of a rolled steel plate is 54 m;
(3) pre-cooling: pre-straightening the rolled steel plate to ensure that the steel plate is straight, then entering a pre-cooling device, starting cooling water after the steel plate passes through 1m, keeping the cooling speed at 5 ℃/s, then continuously reducing the water quantity, closing the cooling water at a position 2m away from the tail of the steel plate, and keeping the temperature of the steel plate before ACC entering to be 710-713 ℃;
(4) ACC cooling: and carrying out ACC water cooling on the steel plate, keeping the cooling speed unchanged, keeping the final cooling temperature at 410 ℃, and cooling the steel plate in the air to room temperature after leveling.
The steel plate manufactured by adopting the element component content and the processing technology steps has the thickness specification of 6mm 2620mm, and the mechanical properties of the steel plate are shown in table 2.
TABLE 2 list of mechanical properties of steel sheets in the examples of the present invention
As can be seen from Table 2, the steel sheets manufactured by the method for manufacturing the ultra-long thin single-rolled steel sheet with the length of more than or equal to 50m according to the present invention were subjected to a room temperature tensile test and a-40 ℃ longitudinal impact test, and the results were as follows: the steel plate obtained at normal temperature has a head-to-tail yield strength difference of less than or equal to 30MPa, a tensile strength difference of less than or equal to 20MPa, an elongation of more than or equal to 20%, a-40 ℃ transverse and longitudinal impact energy of more than or equal to 120J, a grain size difference within 0.5 grade, good uniformity and capability of meeting the manufacturing requirements of structural steel for bridges, buildings, ships, ocean platforms and the like.
The embodiments described above are merely specific examples of the present invention exemplified for explaining the present invention, and do not limit the present invention in any way, and any insubstantial changes from the contents and forms described above, which do not depart from the scope of the claims of the present invention, should be construed as falling within the scope of the claims of the present invention.
Claims (4)
1. The super-long thin-specification structural steel plate with the length being more than or equal to 50m is characterized by comprising the following chemical components in percentage by mass: c: 0.05-0.16%, Mn: 0.6-2.0%, Si: 0.10-0.80%, P is less than or equal to 0.020%, S is less than or equal to 0.003%, Nb: 0.000 to 0.040%, Als: 0.010-0.045%, Ti: 0.050-0.050% and the balance of Fe and inevitable impurity elements;
the rolling method of the steel plate comprises the following steps:
(1) heating a casting blank: pouring to obtain a continuous casting slab with the thickness of 160-250 mm, heating the continuous casting slab, and controlling the temperature of a soaking section to be 1150-1250 ℃ and the heating rate to be 8-11 min/cm;
(2) controlling rolling: in the rough rolling stage, high temperature and high pressure are adopted, the billet is taken out of the furnace and then is descaled, the rolling is started, the initial rolling temperature is 1130-1170 ℃, the final rolling temperature is controlled to be more than 1000 ℃, and the thickness of the rolling stop is 2.5-3.5 times of the thickness of a finished product; during finish rolling, cooling water for a roller way and a roller body of a rolling mill is reduced, the opening degree of the cooling water is controlled according to 20-30%, the start rolling temperature of the finish rolling is 880-1000 ℃, high-pressure water is not pumped in the rolling process, the rolling process is not stopped, the finish rolling temperature of the finish rolling is controlled to be 830-890 ℃, and the length of a rolled steel plate is more than or equal to 50 m;
(3) pre-cooling: pre-straightening the rolled steel plate to ensure the steel plate to be straight, then entering a pre-cooling device, starting cooling water after the steel plate passes through 1m, keeping the cooling speed at 5 ℃/s, then continuously reducing the water quantity, and closing the cooling water at a position 2m away from the tail part of the steel plate so as to control the temperature before ACC to be 710-720 ℃;
(4) ACC cooling: and carrying out ACC water cooling on the steel plate, keeping the cooling speed unchanged, keeping the final cooling temperature at 400-600 ℃, and cooling the steel plate to room temperature in the air after leveling.
2. The ultra-long thin gauge structural steel plate with a length of 50m or more according to claim 1, wherein: the yield strength difference between the head, the middle and the tail of the steel plate at normal temperature is less than or equal to 30MPa, the tensile strength difference is less than or equal to 20MPa, the elongation is more than or equal to 20 percent, the transverse and longitudinal impact energy at minus 40 ℃ is more than or equal to 120J, the obtained structure is uniform, and the grain size difference is within 0.5 grade.
3. The ultra-long thin gauge structural steel plate with a length of 50m or more according to claim 1, wherein: the thickness of the steel plate is 6-20 mm.
4. The method for rolling an ultra-long thin gauge structural steel plate with a length of 50m or more according to claim 1, 2 or 3, comprising slab heating, controlled rolling, pre-cooling, and ACC cooling, wherein:
(1) heating a casting blank: pouring to obtain a continuous casting slab with the thickness of 160-250 mm, heating the continuous casting slab, and controlling the temperature of a soaking section to be 1150-1250 ℃ and the heating rate to be 8-11 min/cm;
(2) controlling rolling: in the rough rolling stage, high temperature and high pressure are adopted, the billet is taken out of the furnace and then is descaled, the rolling is started, the initial rolling temperature is 1130-1170 ℃, the final rolling temperature is controlled to be more than 1000 ℃, and the thickness of the rolling stop is 2.5-3.5 times of the thickness of a finished product; during finish rolling, cooling water for a roller way and a roller body of a rolling mill is reduced, the opening degree of the cooling water is controlled according to 20-30%, the start rolling temperature of the finish rolling is 880-1000 ℃, high-pressure water is not pumped in the rolling process, the rolling process is not stopped, the finish rolling temperature of the finish rolling is controlled to be 830-890 ℃, and the length of a rolled steel plate is more than or equal to 50 m;
(3) pre-cooling: pre-straightening the rolled steel plate to ensure the steel plate to be straight, then entering a pre-cooling device, starting cooling water after the steel plate passes through 1m, keeping the cooling speed at 5 ℃/s, then continuously reducing the water quantity, and closing the cooling water at a position 2m away from the tail part of the steel plate so as to control the temperature before ACC to be 710-720 ℃;
(4) ACC cooling: and carrying out ACC water cooling on the steel plate, keeping the cooling speed unchanged, keeping the final cooling temperature at 400-600 ℃, and cooling the steel plate to room temperature in the air after leveling.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110543376.7A CN113235008B (en) | 2021-05-19 | 2021-05-19 | Ultra-long thin structural steel plate with length being larger than or equal to 50m and rolling method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110543376.7A CN113235008B (en) | 2021-05-19 | 2021-05-19 | Ultra-long thin structural steel plate with length being larger than or equal to 50m and rolling method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113235008A true CN113235008A (en) | 2021-08-10 |
| CN113235008B CN113235008B (en) | 2022-05-13 |
Family
ID=77137449
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110543376.7A Active CN113235008B (en) | 2021-05-19 | 2021-05-19 | Ultra-long thin structural steel plate with length being larger than or equal to 50m and rolling method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113235008B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113699449A (en) * | 2021-08-27 | 2021-11-26 | 宝武集团鄂城钢铁有限公司 | Thin-specification single-rolling easy-welding steel plate for atmospheric corrosion resistant bridge and rolling method thereof |
| CN115558851A (en) * | 2022-09-23 | 2023-01-03 | 鞍钢股份有限公司 | Hot rolled steel plate for 370 MPa-level engineering structure and manufacturing method thereof |
| CN115627415A (en) * | 2022-09-28 | 2023-01-20 | 山东钢铁集团日照有限公司 | Low-cost thick-specification high-strength hot-rolled strip steel for pipe piles and preparation method thereof |
| CN115679216A (en) * | 2022-11-08 | 2023-02-03 | 鞍钢股份有限公司 | Method for controlling cooling uniformity of steel plate for economic 345 MPa-level engineering structure |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6044122A (en) * | 1983-08-19 | 1985-03-09 | Kawasaki Steel Corp | Method and apparatus for cooling hot rolled steel plate |
| JPH1017999A (en) * | 1996-06-27 | 1998-01-20 | Kawasaki Steel Corp | Hot rolled ferritic stainless steel plate excellent in corrosion resistance, formability, and uniformity of material, and its production |
| JP2007231312A (en) * | 2006-02-28 | 2007-09-13 | Jfe Steel Kk | High-tensile-strength steel and manufacturing method therefor |
| CN102352463A (en) * | 2011-10-20 | 2012-02-15 | 南京钢铁股份有限公司 | Structural steel plate for low-crack-sensitivity offshore platform and production method thereof |
| CN103484768A (en) * | 2013-09-30 | 2014-01-01 | 武汉钢铁(集团)公司 | High-strength engineering steel plate with length of larger than or equal to 30 m and production method |
| CN108914007A (en) * | 2018-08-10 | 2018-11-30 | 武汉钢铁集团鄂城钢铁有限责任公司 | A kind of the low yield strength ratio high-performance bridge steel plate plate and its manufacturing method of low-carbon and low-alloy |
| CN110079740A (en) * | 2019-06-14 | 2019-08-02 | 武汉钢铁集团鄂城钢铁有限责任公司 | A kind of 530MPa grades of automobile cold stamping axle housing steel plates of high tenacity hot rolling and its manufacturing method |
| CN110106446A (en) * | 2019-06-24 | 2019-08-09 | 新余钢铁股份有限公司 | A kind of 400MPa grades of hot rolled ribbed bars containing Ti and its production technology |
-
2021
- 2021-05-19 CN CN202110543376.7A patent/CN113235008B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6044122A (en) * | 1983-08-19 | 1985-03-09 | Kawasaki Steel Corp | Method and apparatus for cooling hot rolled steel plate |
| JPH1017999A (en) * | 1996-06-27 | 1998-01-20 | Kawasaki Steel Corp | Hot rolled ferritic stainless steel plate excellent in corrosion resistance, formability, and uniformity of material, and its production |
| JP2007231312A (en) * | 2006-02-28 | 2007-09-13 | Jfe Steel Kk | High-tensile-strength steel and manufacturing method therefor |
| CN102352463A (en) * | 2011-10-20 | 2012-02-15 | 南京钢铁股份有限公司 | Structural steel plate for low-crack-sensitivity offshore platform and production method thereof |
| CN103484768A (en) * | 2013-09-30 | 2014-01-01 | 武汉钢铁(集团)公司 | High-strength engineering steel plate with length of larger than or equal to 30 m and production method |
| CN108914007A (en) * | 2018-08-10 | 2018-11-30 | 武汉钢铁集团鄂城钢铁有限责任公司 | A kind of the low yield strength ratio high-performance bridge steel plate plate and its manufacturing method of low-carbon and low-alloy |
| CN110079740A (en) * | 2019-06-14 | 2019-08-02 | 武汉钢铁集团鄂城钢铁有限责任公司 | A kind of 530MPa grades of automobile cold stamping axle housing steel plates of high tenacity hot rolling and its manufacturing method |
| CN110106446A (en) * | 2019-06-24 | 2019-08-09 | 新余钢铁股份有限公司 | A kind of 400MPa grades of hot rolled ribbed bars containing Ti and its production technology |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113699449A (en) * | 2021-08-27 | 2021-11-26 | 宝武集团鄂城钢铁有限公司 | Thin-specification single-rolling easy-welding steel plate for atmospheric corrosion resistant bridge and rolling method thereof |
| CN115558851A (en) * | 2022-09-23 | 2023-01-03 | 鞍钢股份有限公司 | Hot rolled steel plate for 370 MPa-level engineering structure and manufacturing method thereof |
| CN115627415A (en) * | 2022-09-28 | 2023-01-20 | 山东钢铁集团日照有限公司 | Low-cost thick-specification high-strength hot-rolled strip steel for pipe piles and preparation method thereof |
| CN115627415B (en) * | 2022-09-28 | 2024-04-16 | 山东钢铁集团日照有限公司 | Hot-rolled strip steel for low-cost thick-specification high-strength tubular pile and preparation method thereof |
| CN115679216A (en) * | 2022-11-08 | 2023-02-03 | 鞍钢股份有限公司 | Method for controlling cooling uniformity of steel plate for economic 345 MPa-level engineering structure |
| CN115679216B (en) * | 2022-11-08 | 2023-11-10 | 鞍钢股份有限公司 | Economical 345MPa grade steel plate cooling uniformity control method for engineering structure |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113235008B (en) | 2022-05-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113235008B (en) | Ultra-long thin structural steel plate with length being larger than or equal to 50m and rolling method thereof | |
| WO2020169075A1 (en) | High-strength weather-proof thin steel strip and production method therefor | |
| CN109465295B (en) | Method for preventing edge cracking and strip breakage of hot continuous rolled steel plate in cold rolling | |
| CN112981235B (en) | Hardened and tempered steel plate with yield strength of 420MPa grade for building structure and production method thereof | |
| CN109266958B (en) | F-grade steel for series ship and ocean engineering and flexible production method thereof | |
| CN100500914C (en) | Method for rolling thick specification low-alloy structure steel plate by using middle and thin plate blank | |
| CN1995431A (en) | Method for medium sized or thin plate blank continuous casting and continuous rolling for producing superfine crystal grain steel plate and the steel plate | |
| CN106636747B (en) | A kind of manufacturing method using heavy and medium plate mill double annealing production technical pure titanium plate | |
| CN109266815B (en) | Shape control method for online quenching high-strength steel plate | |
| CN111155028B (en) | Steel plate for normalized DH36 wind power and preparation method thereof | |
| RU2518847C2 (en) | Cold rolling process whereat high-silica strip steel cracking is ruled out | |
| CN105177422B (en) | Ultra-long thin EH36 steel and production method of ultra-long thin EH36 steel on steckle mill | |
| CN105689408A (en) | Hot rolling control method for scale on edges of low-carbon aluminum killed steel | |
| DE112020004462T9 (en) | REFRACTORY AND WEATHERING RESISTANT STEEL SHEET/STRIP AND METHOD OF MAKING THE SAME | |
| CN104438326B (en) | Rolling technology for high-carbon steel in thin slab casting and rolling | |
| CN110735085A (en) | Manufacturing method of thin Q345qE and Q370qE steel plates | |
| CN107142364A (en) | A kind of super-purity ferrite stainless steel double roll strip casting rolling production process | |
| CN104451379A (en) | High-strength low-alloy niobium-vanadium structural steel and preparation method thereof | |
| CN105624382A (en) | Hot-rolling method for V-Ti microalloyed steel | |
| CN110004359B (en) | High-uniformity longitudinal and transverse toughness wide steel plate and TMCP (thermal mechanical control processing) process production method thereof | |
| CN114411061B (en) | High-strength anti-seismic steel bar and preparation method thereof | |
| CN105925889A (en) | Ultrathick specification 1.2311 mold steel plate and preparation method thereof | |
| CN113522988B (en) | Control method for shape of thin-specification ultrahigh-strength steel plate in DQ (data-from-data) process | |
| CN102021293A (en) | Minimizing rolling method of Q345q | |
| CN109023110B (en) | 500 MPa-level thin-specification hot-rolled automobile structural steel produced by adopting short process and method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |