WO2021106723A1 - 鋼板の製造設備及び製造方法 - Google Patents
鋼板の製造設備及び製造方法 Download PDFInfo
- Publication number
- WO2021106723A1 WO2021106723A1 PCT/JP2020/043061 JP2020043061W WO2021106723A1 WO 2021106723 A1 WO2021106723 A1 WO 2021106723A1 JP 2020043061 W JP2020043061 W JP 2020043061W WO 2021106723 A1 WO2021106723 A1 WO 2021106723A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- steel sheet
- steel plate
- straightening
- shape
- temperature
- Prior art date
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 174
- 239000010959 steel Substances 0.000 title claims abstract description 174
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 40
- 238000001816 cooling Methods 0.000 claims abstract description 68
- 238000010791 quenching Methods 0.000 claims abstract description 56
- 238000010438 heat treatment Methods 0.000 claims abstract description 54
- 230000000171 quenching effect Effects 0.000 claims abstract description 54
- 238000000034 method Methods 0.000 claims description 17
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 15
- 229910000760 Hardened steel Inorganic materials 0.000 claims description 3
- 238000012937 correction Methods 0.000 abstract description 7
- 238000005096 rolling process Methods 0.000 description 11
- 239000000498 cooling water Substances 0.000 description 6
- 239000000463 material Substances 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 5
- 230000007547 defect Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 238000005098 hot rolling Methods 0.000 description 5
- 229910001566 austenite Inorganic materials 0.000 description 3
- 238000005452 bending Methods 0.000 description 3
- 230000007246 mechanism Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000013461 design Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000011144 upstream manufacturing Methods 0.000 description 2
- 230000001133 acceleration Effects 0.000 description 1
- 238000005422 blasting Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 238000005541 quenching (cooling) Methods 0.000 description 1
- 230000003252 repetitive effect Effects 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/0056—Furnaces through which the charge is moved in a horizontal straight path
-
- 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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D1/00—Straightening, restoring form or removing local distortions of sheet metal or specific articles made therefrom; Stretching sheet metal combined with rolling
- B21D1/05—Stretching combined with rolling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
- C21D1/19—Hardening; Quenching with or without subsequent tempering by interrupted quenching
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
- C21D1/28—Normalising
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/56—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering characterised by the quenching agents
- C21D1/60—Aqueous agents
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/62—Quenching devices
- C21D1/63—Quenching devices for bath quenching
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0236—Cold rolling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0242—Flattening; Dressing; Flexing
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/0062—Heat-treating apparatus with a cooling or quenching zone
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
- C21D9/54—Furnaces for treating strips or wire
- C21D9/56—Continuous furnaces for strip or wire
-
- 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
- B21B2001/221—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 cold-rolling
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D1/00—Straightening, restoring form or removing local distortions of sheet metal or specific articles made therefrom; Stretching sheet metal combined with rolling
- B21D1/02—Straightening, restoring form or removing local distortions of sheet metal or specific articles made therefrom; Stretching sheet metal combined with rolling by rollers
Definitions
- the present invention relates to a steel sheet manufacturing facility and a manufacturing method.
- cooling from a high temperature is often performed in order to adjust mechanical properties such as strength. Cooling is roughly divided into an online water cooling method and an offline water cooling method.
- the online water cooling method the steel sheet after hot rolling is water cooled using a water cooling device arranged online.
- the offline water cooling method the rolled material is once cooled to room temperature, and then heated and water cooled again in a heat treatment furnace arranged offline.
- the online water cooling method is advantageous, but since the steel sheet tends to warp during rolling, it is not possible to arrange a cooling device in the vicinity of the rolling mill. As a result, the temperature drops during transportation to the cooling device after rolling, so there is a problem that water cooling cannot be performed at an appropriate temperature.
- a cooling device is arranged on the outlet side of the heating furnace, and quenching can be performed from a temperature substantially equal to the heating temperature, which is advantageous for adjusting mechanical characteristics.
- hot-rolled steel sheets are prone to temperature unevenness during cooling due to differences in the temperature distribution, shape, or surface condition of the steel sheets immediately after rolling.
- the temperature unevenness of the steel sheet may be due to the performance of the cooling device.
- the temperature unevenness of the steel sheet occurs, the steel sheet is deformed, residual stress, material variation, and the like occur after cooling.
- various cooling devices capable of uniform cooling have been developed.
- the method being developed is only an improvement of the cooling device, and in particular, flattening of the steel sheet after cooling has not been completely achieved. Poor shape of the steel sheet after cooling causes troubles in operation such as a plate passage failure in the production line, and requires a precision treatment by a press or a straightening device in a post-process, resulting in high cost.
- temperature unevenness of the steel sheet There are two types of temperature unevenness of the steel sheet, one is due to the design of the cooling nozzle and the other is due to the shape of the steel sheet during rolling. Depending on the design of the cooling nozzle, temperature deviation on the upper and lower surfaces and temperature non-uniformity in the width direction may occur. On the other hand, if the shape of the steel sheet during rolling is poor, the cooling water does not flow evenly on the steel sheet and the cooling capacity changes depending on the location, resulting in temperature unevenness.
- Patent Documents 1 and 2 it is an object of the first shape straightening device to straighten the shape of a steel sheet to such an extent that draining can be sufficiently performed by a draining roll in the cooling device.
- Patent Documents 1 and 2 propose an online process in which after straightening by the first shape straightening device, accelerated cooling is performed, and then final straightening is performed by the second shape straightening device.
- a great effect can be obtained on the occurrence of temperature unevenness caused by the cooling nozzle and the cooling strain caused by it, such as the temperature deviation on the upper and lower surfaces and the uniformity in the width direction described above. I can't.
- the conventional offline heat treatment equipment is arranged in the order of the heating furnace, the quenching device, and the shape correction device.
- the quenching device is cooled to 100 ° C. or lower, and even if the cooling uniformity is not ensured, the final cooling stop temperature of the steel sheet is constant because it is cooled to a low temperature close to the water temperature of the cooling water. .. Therefore, the uniformity of cooling was not considered.
- the temperature of the steel sheet after the completion of cooling also varies, so that not only the predetermined quality cannot be ensured, but also the steel sheet is distorted due to the difference in thermal expansion in the plane of the steel sheet temperature.
- the present invention has been made in view of such circumstances, and a steel sheet manufacturing facility and a manufacturing method capable of performing more uniform cooling during heat treatment of a steel sheet and producing a flat and uniform steel sheet.
- the challenge is to provide.
- a steel sheet manufacturing facility for heat-treating a steel sheet, a heating furnace for heating the steel sheet at 100 ° C. or lower, and a first shape straightening for flattening the heated steel sheet.
- a steel sheet manufacturing facility including an apparatus, a quenching device for quenching the straightened steel sheet, and a second shape straightening device for flattening the hardened steel sheet.
- a method for manufacturing a steel plate which heats the steel plate, wherein the steel plate is flattened after a heating step of heating the steel plate at 100 ° C. or lower and the heating step.
- a method for manufacturing a steel plate comprising a straightening step of the above, a quenching step of quenching the steel plate after the first straightening step, and a second straightening step of flattening the steel plate after the quenching step. Is provided.
- FIG. 1 shows a schematic configuration of a heat treatment facility 1 for a thick steel sheet 2, which is a steel sheet manufacturing facility according to an embodiment of the present invention
- FIG. 2 shows a first shape straightening device 4 and a quenching device 5 according to the present embodiment. The detailed configuration of each is shown.
- the main focus is on adjusting the mechanical properties of the material with an offline heat treatment facility that is not directly connected to the rolling line. Not directly connected to the rolling line.
- the heat treatment equipment 1 is equipment for heat-treating a thick steel plate 2 which is a steel plate, and includes a heating furnace 3, a first shape straightening device 4, a quenching device 5, and a second shape straightening device 6. Further, as shown in FIG. 1, in the heat treatment equipment 1, the heating furnace 3, the first shape straightening device 4, the quenching device 5, and the second shape straightening device 6 are arranged in this order from the upstream side in the transport direction of the thick steel plate 2. Be arranged. Further, a transport roller (not shown) for transporting the thick steel plate 2 is provided between each of the heating furnace 3, the first shape straightening device 4, the quenching device 5, and the second shape straightening device 6.
- the heating furnace 3 heats the thick steel plate 2 having finished hot rolling at 100 ° C. or lower to the austenite temperature range.
- the thick steel plate 2 is a steel plate having a thickness of 4.0 mm or more.
- the first shape straightening device 4 is a device for flattening the thick steel plate 2 heated in the heating furnace 3, and is provided between the heating furnace 3 and the quenching device 5.
- the temperature of the thick steel plate 2 drops from the time when the thick steel plate 2 is extracted from the heating furnace 3 to the time when the first shape straightening device 4 is reached.
- the smaller the temperature drop the smaller the increase in the deformation resistance of the thick steel plate 2, and the shape can be corrected with a small straightening force. Therefore, it is preferable that the distance from the heating furnace 3 to the first shape straightening device 4 is 4 m or less.
- the first shape straightening device 4 is preferably small in size and has a small installation space in order to shorten the transport time from the heating furnace 3 to the quenching device 5.
- the first shape straightening device 4 straightens the thick steel plate 2 having a relatively low deformation resistance during heat, it is preferable to use a shape straightening device having a lower load capacity than the second shape straightening device 6. ..
- the first shape straightening device 4 may have a load capacity of at least 500 ton, preferably about 3000 ton. In this embodiment, ton indicates metric ton.
- the quenching device 5 is a device that quenches the thick steel plate 2 shape-corrected by the first shape-correcting device 4 by water cooling. As shown in FIG. 2, the quenching device 5 has an upper cooling nozzle 51 and a lower cooling nozzle 52 as a device for rapidly cooling the thick steel plate 2 after shape correction. A plurality of upper cooling nozzles 51 and lower cooling nozzles 52 are provided in pairs in the vertical direction with respect to the transport line in the width direction of the thick steel plate 2, and at a predetermined pitch along the transport direction of the thick steel plate 2. It is arranged in multiple places side by side. Cooling water 53 is injected toward the thick steel plate 2 from each cooling nozzle of the upper cooling nozzle 51 and the lower cooling nozzle 52.
- restraint rolls 50 may be installed before and after the upper cooling nozzle 51 and the lower cooling nozzle 52, respectively.
- the restraint roll 50 even if the thick steel plate 2 is distorted due to uneven cooling or the like, the thick steel plate 2 can be restrained to some extent, so that out-of-plane deformation can be prevented.
- the second shape straightening device 6 is a device for flattening the thick steel plate 2 hardened by the quenching device 5, and is provided on the exit side of the quenching device 5 (downstream side in the transport direction of the thick steel plate 2).
- a reduction type skin path straightening device a repeatedly bending type roller leveler straightening device, or a press type straightening device can be used.
- a roller leveler straightening device for the second shape straightening device 6.
- the second shape straightening device 6 preferably has a high straightening reaction force in terms of performing shape straightening of the thick steel plate 2 near room temperature, and preferably has a load capacity of at least 2000 ton or more.
- a slab or the like is used as a material and hot-rolled on a hot rolling line (not shown) different from the heat treatment equipment 1 to obtain a predetermined thickness (not shown).
- a thick steel plate 2 having a width (for example, 2000 mm) and a width (for example, 2000 mm) is manufactured.
- the hot-rolled thick steel sheet 2 is cooled to room temperature, and then the scale is removed by a surface scale removing device (not shown).
- the thick steel plate 2 from which the scale has been removed is charged into the heating furnace 3 and heated to the austenite temperature range (for example, about 910 ° C.) (heating step).
- the thick steel plate 2 is extracted from the heating furnace 3 and conveyed to the first shape straightening device 4 by a plurality of table rolls (not shown) installed on the outlet side of the heating furnace 3, and the first shape straightening is performed. It is flattened (flattened) by the device 4 (first straightening step).
- the reason for installing the first shape straightening device 4 in front of the quenching device 5 on the upstream side in the transport direction of the thick steel plate 2) will be described below.
- the thick steel plate 2 is hot-rolled in advance to a predetermined thickness and width on a hot rolling line different from that of the heat treatment equipment 1.
- the degree of heat shrinkage in the process of cooling to room temperature differs depending on the portion of the thick steel plate 2, so that a shape defect occurs after cooling.
- the heat treatment equipment 1 since the thick steel plate 2 is inserted into the heating furnace 3 with the shape defect occurring, the shape defect remains even if it is uniformly heated in the heating furnace 3.
- the thick steel plate 2 is flattened by the first shape straightening device 4 and cooled by the quenching device 5, so that the thick steel plate 2 with high flatness is obtained. Can be manufactured. That is, in order to obtain the effect of the present invention, it is necessary to flatten the shape (initial shape) of the thick steel plate 2 before entering the quenching apparatus 5.
- the first shape straightening device 4 is a roller leveler straightening device capable of repeated bending than a skin path straightening device having a low straightening ability against warpage in the longitudinal direction generated at the tip and tail end of the thick steel plate 2.
- the roller leveler straightening device is a straightening machine that repeatedly bends by a plurality of rolls (for example, four upper surfaces and three lower surfaces), and the straightening effect is relatively low at a distance corresponding to the roll pitch. Therefore, when a roller leveler straightening device is used, it is more preferable to further provide a press-type straightening mechanism or the like capable of correcting the warp of the tip tail end portion of the thick steel plate 2.
- the temperature of the thick steel plate 2 at the time of shape straightening by the first shape straightening device 4 is preferably in the range of the temperature Ar 3 temperature ⁇ 150 ° C. at which the austenite of the thick steel plate 2 is transformed into ferrite. By setting such a temperature, the yield stress of the thick steel plate 2 becomes sufficiently low, and the reaction force at the time of shape correction can be reduced.
- the thick steel plate 2 is quenched by the quenching device 5 (quenching step).
- the thick steel plate 2 is straightened by the second shape straightening device 6 (second straightening step).
- second straightening step In quenching (cooling) by the quenching device 5, it is difficult to manage so that the flow rates of the cooling water 53 injected from the upper cooling nozzle 51 and the lower cooling nozzle 52 in the width direction are completely matched. For this reason, there remains a risk of slight warpage due to temperature unevenness during quenching, so it is necessary to further straighten the thick steel plate 2 with the second shape straightening device 6. Further, it is preferable that the temperature of the thick steel plate 2 is 100 ° C. or lower at the time of straightening by the second shape straightening device 6.
- the steel plate is a thick steel plate 2 having a plate thickness of 4.0 mm or more, but the present invention is not limited to such examples.
- the steel plate may have a thickness of less than 4.0 mm.
- the present invention is suitable for a steel plate having a plate thickness of 4.0 mm or more, and is more suitable for a steel plate having a plate thickness of 6.0 mm or more.
- the steel sheet (for example, thick steel sheet 2) manufacturing facility (heat treatment facility 1) is a steel sheet manufacturing facility that heats a steel sheet and heats a steel sheet at 100 ° C. or lower. 3, a first shape straightening device 4 for flattening a heated steel sheet, a quenching device 5 for quenching a straightened steel sheet, and a second shape straightening device 6 for flattening a hardened steel sheet. , Equipped with.
- the steel sheet with the first shape straightening device 4 cooling at the time of quenching can be made uniform. Therefore, the steel sheet can be made flat and homogeneous.
- the finally manufactured steel sheet can be flattened even if the cooling of the quenching device 5 is uneven.
- the load capacity of the first shape straightening device 4 is lower than the load capacity of the second shape straightening device 6.
- the load capacity can be optimized according to the difference in deformation resistance due to the difference in the temperature of the steel sheet, and the first shape straightening device 4 provides a high load capacity straightening device. Since it is not used, the initial equipment installation cost is low.
- the temperature of the steel sheet is in the range of Ar 3 temperature ⁇ 150 ° C. at the time of straightening by the first shape straightening device 4. According to the configuration of (3) above, the yield stress of the steel sheet is sufficiently low, and the reaction force at the time of shape correction can be reduced.
- the temperature of the steel sheet is 100 ° C. or lower at the time of straightening by the second shape straightening device 6. According to the configuration of (4) above, the straightening temperature becomes almost room temperature, and re-deformation due to heat shrinkage due to a further temperature drop does not occur after straightening, so that a good shape can be obtained.
- the first shape straightening device 4 and the second shape straightening device 6 are roller leveler straightening devices. According to the configuration of (5) above, the warp at the tip and tail end of the steel sheet can be corrected.
- the quenching apparatus quenchs the steel sheet by water cooling.
- the method for producing a steel plate according to one aspect of the present invention is a method for producing a steel plate in which the steel plate is heat-treated. It is provided with a first straightening step for straightening, a quenching step for quenching the steel plate after the first straightening step, and a second straightening step for flattening the steel plate after the quenching step.
- the temperature of the steel sheet at the time of straightening is in the range of Ar 3 temperature ⁇ 150 ° C.
- the temperature of the steel sheet is 100 ° C. or lower in the second straightening step. According to the above configurations (7) to (9), the same effect as the above configurations (1), (3), and (4) can be obtained.
- a thick steel plate 2 (plate thickness 6 mm, 12 mm, 25 mm, 40 mm ⁇ plate width 3500 mm ⁇ plate length 7 m) in a room temperature state from which scale has been removed by shot blasting in advance is heated.
- the furnace 3 was heated to 900 ° C. in a nitrogen atmosphere.
- the heated thick steel plate 2 was extracted, the thick steel plate 2 was straightened by the first shape straightening device 4 (roller leveler type), and the thick steel plate 2 was hardened to 100 ° C. or lower by the quenching device 5. Then, the hardened thick steel plate 2 was shape-corrected again by the second shape-correcting device 6.
- the quenching device 5 used spray nozzles as cooling nozzles 51 and 52.
- the Ar 3 temperature of this material was 800 ° C.
- the temperature of the thick steel plate 2 when extracted from the heating furnace 3 and straightened by the first shape straightening device 4 was about 860 ° C.
- the shape of the steel plate when the thick steel plate 2 was heat-treated with the above equipment arrangement was investigated.
- the thick steel plate 2 was placed on the surface plate, and the amount obtained by subtracting the plate thickness from the maximum height of the thick steel plate 2 with respect to the surface plate surface (referred to as the warpage amount) was measured. It became like 1 to 4.
- the permissible value of the amount of warpage of the thick steel plate 2 is 5 mm or less.
- the amount of warpage was 5 mm or less, and the shape was good (evaluation: ⁇ ).
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Straightening Metal Sheet-Like Bodies (AREA)
- Metal Rolling (AREA)
- Heat Treatment Of Strip Materials And Filament Materials (AREA)
Abstract
Description
一般に、熱間圧延された鋼板は、圧延直後の鋼板の温度分布や形状、又は表面状態の相違に起因して、冷却中に温度むらが生じやすい。さらに、鋼板の温度むらは、冷却装置の性能にも起因することがある。そして、鋼板の温度むらが発生すると、冷却後に鋼板の変形や残留応力、材質のバラツキ等が発生する。この対策として各種の均一な冷却が可能な冷却装置が開発されている。しかし、開発されている方法は冷却装置のみの改善であり、特に冷却後の鋼板の平坦化は完全には達成されていない。冷却後の鋼板の形状不良は、製造ラインの通板障害など、操業上のトラブルの原因となり、後工程でプレスや矯正装置による精整処理を要するのでコスト高ともなる。
図1には、本発明の一実施形態に係る鋼板の製造設備である厚鋼板2の熱処理設備1の概略構成、図2には、本実施形態における第1の形状矯正装置4及び焼入れ装置5の詳細な構成がそれぞれ示されている。本実施形態では、均質な温度と形状を確保するために、圧延ラインと直結していないオフライン型の熱処理設備で素材の機械的特性を調整することに主眼を置いており、熱処理設備1は、圧延ラインと直結していない。熱処理設備1は、鋼板である厚鋼板2を熱処理する設備であり、加熱炉3と、第1の形状矯正装置4と、焼入れ装置5と、第2の形状矯正装置6とを備える。また、図1に示すように、熱処理設備1では、厚鋼板2の搬送方向の上流側から、加熱炉3、第1の形状矯正装置4、焼入れ装置5及び第2の形状矯正装置6が順に配される。さらに、加熱炉3、第1の形状矯正装置4、焼入れ装置5及び第2の形状矯正装置6の各装置間には、厚鋼板2を搬送する搬送ローラ(図示しない)がそれぞれ設けられる。
第1の形状矯正装置4は、加熱炉3で加熱された厚鋼板2を平坦に矯正する装置であり、加熱炉3と焼入れ装置5との間に設けられる。第1の形状矯正装置4には、圧下型のスキンパス矯正装置又は繰り返し曲げ型のローラーレベラ矯正装置を用いることができる。また、後述する理由から、第1の形状矯正装置4には、ローラーレベラ矯正装置を用いることが好ましい。さらに、後述する理由から、ローラーレベラ矯正装置を用いる場合には、厚鋼板2の先尾端部の反りを修正することが可能なプレス型の矯正機構などをさらに設けることがより好適である。
本実施形態に係る厚鋼板の製造方法では、まず、鋳片等を素材として、熱処理設備1とは別の熱間圧延ライン(図示せず)で熱間圧延をすることで、所定の厚み(例えば、30mm)及び幅(例えば、2000mm)の厚鋼板2を製造する。次いで、熱間圧延された厚鋼板2は、室温になるまで冷却された後、表面スケール除去装置(図示せず)でスケールが除去される。
その後、加熱炉3から厚鋼板2を抽出し、加熱炉3の出側に設置されている複数のテーブルロール(図示せず)により第1の形状矯正装置4に搬送され、第1の形状矯正装置4で平坦に矯正(平坦化)される(第1の矯正工程)。
第1の矯正工程の後、厚鋼板2を焼入れ装置5で焼入れする(焼入れ工程)。
以上で、特定の実施形態を参照して本発明を説明したが、これら説明によって発明を限定することを意図するものではない。本発明の説明を参照することにより、当業者には、開示された実施形態とともに種々の変形例を含む本発明の別の実施形態も明らかである。従って、特許請求の範囲に記載された発明の実施形態には、本明細書に記載したこれらの変形例を単独または組み合わせて含む実施形態も網羅すると解すべきである。
例えば、上記実施形態では、鋼板が4.0mm以上の板厚を有する厚鋼板2であるとしたが、本発明はかかる例限定されない。鋼板は、板厚が4.0mm未満のものであってもよい。なお、本発明は、板厚が4.0mm以上の鋼板に好適なものであり、板厚6.0mm以上の鋼板により好適なものである。
(1)本発明の一態様に係る鋼板(例えば厚鋼板2)の製造設備(熱処理設備1)は、鋼板を熱処理する、鋼板の製造設備であって、100℃以下の鋼板を加熱する加熱炉3と、加熱された鋼板を平坦に矯正する第1の形状矯正装置4と、矯正された鋼板を焼入れする焼入れ装置5と、焼入れされた鋼板を平坦に矯正する第2の形状矯正装置6と、を備える。
上記(1)の構成によれば、第1の形状矯正装置4で鋼板を平坦化することで、焼入れ時の冷却を均一にすることができる。このため、鋼板を平坦で均質なものとすることができる。また、焼入れ後に第2の形状矯正装置6で鋼板を平坦化することで、焼入れ装置5の冷却にむらがある場合でも、最終的に製造される鋼板を平坦にすることができる。
上記(2)の構成によれば、鋼板の温度の違いによる変形抵抗の違いに応じて、耐荷重を適正化することができ、かつ第1の形状矯正装置4では高耐荷重の矯正装置を使用しないため初期設備導入費が安価となる。
(3)上記(1)又は(2)の構成において、第1の形状矯正装置4による矯正時において、鋼板の温度がAr3温度±150℃の範囲である。
上記(3)の構成によれば、鋼板の降伏応力が十分低くなり、形状矯正時の反力を小さくすることができる。
上記(4)の構成によれば、矯正温度がほぼ室温となり、矯正後にさらなる温度低下による熱収縮を起因とした再変形が発生しないため、良好な形状を得ることができる。
(5)上記(1)~(4)のいずれか1つの構成において、第1の形状矯正装置4及び第2の形状矯正装置6は、ローラーレベラ矯正装置である。
上記(5)の構成によれば、鋼板の先尾端部での反りを矯正することができる。このため、鋼板自体の反りの抑制だけでなく、焼入れ時における焼入れ装置5を構成する冷却ノズル等の設備との接触を防止することができる。
(6)上記(1)~(5)のいずれか1つの構成において、焼入れ装置は、鋼板を水冷によって焼入れする。
(8)上記(7)の構成において、第1の矯正工程では、矯正時の鋼板の温度がAr3温度±150℃の範囲である。
(9)上記(7)又は(8)の構成において、第2の矯正工程では、鋼板の温度が100℃以下である。
上記(7)~(9)の構成によれば、上記(1),(3),(4)の構成と同様な効果が得られる。
2 厚鋼板
3 加熱炉
4 第1の形状矯正装置
5 焼入れ装置
50 拘束ロール
51 上側の冷却ノズル
52 下側の冷却ノズル
53 冷却水
6 第2の形状矯正装置
Claims (9)
- 鋼板を熱処理する、鋼板の製造設備であって、
100℃以下の前記鋼板を加熱する加熱炉と、
加熱された前記鋼板を平坦に矯正する第1の形状矯正装置と、
矯正された前記鋼板を焼入れする焼入れ装置と、
焼入れされた前記鋼板を平坦に矯正する第2の形状矯正装置と、
を備える、鋼板の製造設備。 - 前記第1の形状矯正装置の耐荷重は、前記第2の形状矯正装置の耐荷重よりも低い、請求項1に記載の鋼板の製造設備。
- 前記第1の形状矯正装置による矯正時において、前記鋼板の温度がAr3温度±150℃の範囲である、請求項1又は2に記載の鋼板の製造設備。
- 前記第2の形状矯正装置による矯正時において、前記鋼板の温度が100℃以下である、請求項1~3のいずれか1項に記載の鋼板の製造設備。
- 前記第1の形状矯正装置及び前記第2の形状矯正装置は、ローラーレベラ矯正装置である、請求項1~4のいずれか1項に記載の鋼板の製造設備。
- 前記焼入れ装置は、前記鋼板を水冷によって焼入れする、請求項1~5のいずれか1項に記載の鋼板の製造設備。
- 鋼板を熱処理する、鋼板の製造方法であって、
100℃以下の前記鋼板を加熱する加熱工程と、
前記加熱工程の後、前記鋼板を平坦に矯正する第1の矯正工程と、
前記第1の矯正工程の後、前記鋼板を焼入れする焼入れ工程と、
前記焼入れ工程の後、前記鋼板を平坦に矯正する第2の矯正工程と、
を備える、鋼板の製造方法。 - 前記第1の矯正工程では、矯正時の前記鋼板の温度がAr3温度±150℃の範囲である、請求項7に記載の鋼板の製造方法。
- 前記第2の矯正工程では、前記鋼板の温度が100℃以下である、請求項7又は8に記載の鋼板の製造方法。
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2021561349A JP7173377B2 (ja) | 2019-11-25 | 2020-11-18 | 鋼板の製造設備及び製造方法 |
CN202080081150.3A CN114728320A (zh) | 2019-11-25 | 2020-11-18 | 钢板的制造设备及制造方法 |
EP20893260.8A EP4066956A4 (en) | 2019-11-25 | 2020-11-18 | MANUFACTURING PLANT AND METHOD FOR PRODUCTION OF A STEEL PLATE |
KR1020227015900A KR102685815B1 (ko) | 2019-11-25 | 2020-11-18 | 강판의 제조 설비 및 제조 방법 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2019212625 | 2019-11-25 | ||
JP2019-212625 | 2019-11-25 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2021106723A1 true WO2021106723A1 (ja) | 2021-06-03 |
Family
ID=76129339
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2020/043061 WO2021106723A1 (ja) | 2019-11-25 | 2020-11-18 | 鋼板の製造設備及び製造方法 |
Country Status (5)
Country | Link |
---|---|
EP (1) | EP4066956A4 (ja) |
JP (1) | JP7173377B2 (ja) |
KR (1) | KR102685815B1 (ja) |
CN (1) | CN114728320A (ja) |
WO (1) | WO2021106723A1 (ja) |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS57116732A (en) * | 1981-01-13 | 1982-07-20 | Nippon Steel Corp | Continuous heat treatment device train for steel plate |
JPS61126909A (ja) * | 1984-11-21 | 1986-06-14 | Sumitomo Metal Ind Ltd | 厚板圧延ラインにおける加工熱処理設備 |
JPS61262418A (ja) * | 1985-05-17 | 1986-11-20 | Sumitomo Metal Ind Ltd | 厚鋼板の加工熱処理設備 |
JPS6272430A (ja) * | 1985-09-26 | 1987-04-03 | Sumitomo Metal Ind Ltd | 誘導加熱装置を備えた矯正設備 |
JP2002011515A (ja) * | 2001-05-23 | 2002-01-15 | Nkk Corp | 鋼板の製造ライン及び鋼板の製造方法 |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2005074480A (ja) | 2003-09-01 | 2005-03-24 | Sumitomo Metal Ind Ltd | 熱間圧延鋼板の製造設備、及び製造方法 |
JP4360250B2 (ja) * | 2004-03-29 | 2009-11-11 | Jfeスチール株式会社 | 鋼板の製造方法及びその製造設備 |
JP4976906B2 (ja) * | 2007-04-09 | 2012-07-18 | 株式会社神戸製鋼所 | Haz靭性、母材靭性、伸び、及び強度−伸びバランスに優れた厚鋼板 |
CN101633996B (zh) * | 2008-07-25 | 2011-07-20 | 宝山钢铁股份有限公司 | 低成本的700MPa级高强高韧调质钢板及其制造方法 |
JP5614040B2 (ja) * | 2009-03-25 | 2014-10-29 | Jfeスチール株式会社 | 厚鋼板の製造設備及び製造方法 |
JP6343842B2 (ja) * | 2015-08-14 | 2018-06-20 | Jfeスチール株式会社 | 鋼材の冷却方法、鋼材の製造方法、鋼材の冷却装置および鋼材の製造設備 |
JP6720894B2 (ja) * | 2017-03-02 | 2020-07-08 | Jfeスチール株式会社 | 鋼板の冷却方法および鋼板の冷却装置ならびに鋼板の製造方法 |
JP6819469B2 (ja) * | 2017-06-06 | 2021-01-27 | 日本製鉄株式会社 | 熱処理鋼板の製造方法 |
RU2741033C1 (ru) * | 2017-09-28 | 2021-01-22 | ДжФЕ СТИЛ КОРПОРЕЙШН | Производственная установка для производства стального листа и способ производства стального листа |
JP6569843B1 (ja) * | 2017-12-20 | 2019-09-04 | Jfeスチール株式会社 | 厚鋼板の冷却装置および冷却方法ならびに厚鋼板の製造設備および製造方法 |
-
2020
- 2020-11-18 KR KR1020227015900A patent/KR102685815B1/ko active IP Right Grant
- 2020-11-18 WO PCT/JP2020/043061 patent/WO2021106723A1/ja unknown
- 2020-11-18 JP JP2021561349A patent/JP7173377B2/ja active Active
- 2020-11-18 EP EP20893260.8A patent/EP4066956A4/en active Pending
- 2020-11-18 CN CN202080081150.3A patent/CN114728320A/zh active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS57116732A (en) * | 1981-01-13 | 1982-07-20 | Nippon Steel Corp | Continuous heat treatment device train for steel plate |
JPS61126909A (ja) * | 1984-11-21 | 1986-06-14 | Sumitomo Metal Ind Ltd | 厚板圧延ラインにおける加工熱処理設備 |
JPS61262418A (ja) * | 1985-05-17 | 1986-11-20 | Sumitomo Metal Ind Ltd | 厚鋼板の加工熱処理設備 |
JPS6272430A (ja) * | 1985-09-26 | 1987-04-03 | Sumitomo Metal Ind Ltd | 誘導加熱装置を備えた矯正設備 |
JP2002011515A (ja) * | 2001-05-23 | 2002-01-15 | Nkk Corp | 鋼板の製造ライン及び鋼板の製造方法 |
Non-Patent Citations (1)
Title |
---|
See also references of EP4066956A4 * |
Also Published As
Publication number | Publication date |
---|---|
JP7173377B2 (ja) | 2022-11-16 |
KR102685815B1 (ko) | 2024-07-16 |
CN114728320A (zh) | 2022-07-08 |
EP4066956A1 (en) | 2022-10-05 |
EP4066956A4 (en) | 2023-01-11 |
JPWO2021106723A1 (ja) | 2021-06-03 |
KR20220080174A (ko) | 2022-06-14 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5387347B2 (ja) | 鋼板の製造方法 | |
JP6720894B2 (ja) | 鋼板の冷却方法および鋼板の冷却装置ならびに鋼板の製造方法 | |
JP6521193B1 (ja) | 鋼板の製造設備および鋼板の製造方法 | |
JP2015029992A (ja) | ローラーレベラによる鋼板の矯正方法及びローラーレベラ | |
JP4360250B2 (ja) | 鋼板の製造方法及びその製造設備 | |
WO2021106723A1 (ja) | 鋼板の製造設備及び製造方法 | |
JP4289480B2 (ja) | 残留応力のバラツキが少なく形状良好な鋼板を得るための矯正方法 | |
JP4525037B2 (ja) | 鋼板のローラ矯正方法 | |
JP4581418B2 (ja) | 厚鋼板の熱処理方法 | |
JP2001105006A (ja) | 厚鋼板の製造方法およびその装置 | |
JP3661434B2 (ja) | 熱間圧延鋼板の制御冷却方法 | |
KR20240096738A (ko) | 퀀칭 장치 및 금속판의 제조 방법 | |
JP6569691B2 (ja) | 不等辺不等厚山形鋼の製造方法 | |
JP3235784B2 (ja) | 鋼板の製造ライン及び鋼板の製造方法 | |
JP4760022B2 (ja) | 厚鋼板の熱処理装置及び方法並びに厚鋼板の製造方法 | |
JP2002011515A (ja) | 鋼板の製造ライン及び鋼板の製造方法 | |
JP4923429B2 (ja) | ローラーレベラーの設定方法 | |
JP5764935B2 (ja) | 厚鋼板のデスケーリング設備およびデスケーリング方法 | |
JP3171326B2 (ja) | 厚鋼板の製造方法 | |
JP4305156B2 (ja) | 鋼板の熱処理方法 | |
JP2005262273A (ja) | 差厚鋼板の制御冷却方法 | |
JPS63248501A (ja) | H形鋼の反り防止方法 | |
JP2000071003A (ja) | 厚鋼板の製造方法および製造装置 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 20893260 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 2021561349 Country of ref document: JP Kind code of ref document: A |
|
ENP | Entry into the national phase |
Ref document number: 20227015900 Country of ref document: KR Kind code of ref document: A |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
ENP | Entry into the national phase |
Ref document number: 2020893260 Country of ref document: EP Effective date: 20220627 |