CN106583453A - Method for producing ultrathin low-carbon steel by use of thin slab casting and rolling process - Google Patents

Method for producing ultrathin low-carbon steel by use of thin slab casting and rolling process Download PDF

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Publication number
CN106583453A
CN106583453A CN201611230389.4A CN201611230389A CN106583453A CN 106583453 A CN106583453 A CN 106583453A CN 201611230389 A CN201611230389 A CN 201611230389A CN 106583453 A CN106583453 A CN 106583453A
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rolling
temperature
roughing
cooling
thickness
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CN106583453B (en
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陈全忠
陈连龙
吴有生
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Wisdri Engineering and Research Incorporation Ltd
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Wisdri Engineering and Research Incorporation Ltd
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    • 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
    • B21B1/46—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 metal immediately subsequent to continuous casting
    • B21B1/463—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 metal immediately subsequent to continuous casting in a continuous process, i.e. the cast not being cut before rolling
    • 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
    • B21B1/24—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 in a continuous or semi-continuous process
    • B21B1/26—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 in a continuous or semi-continuous process by hot-rolling, e.g. Steckel hot mill
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B15/00—Arrangements for performing additional metal-working operations specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
    • B21B15/0007—Cutting or shearing the product
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/16—Control of thickness, width, diameter or other transverse dimensions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/16—Control of thickness, width, diameter or other transverse dimensions
    • B21B37/22—Lateral spread control; Width control, e.g. by edge rolling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/58—Roll-force control; Roll-gap control
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/58—Roll-force control; Roll-gap control
    • B21B37/62—Roll-force control; Roll-gap control by control of a hydraulic adjusting device
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/74—Temperature control, e.g. by cooling or heating the rolls or the product
    • 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
    • B21B45/004—Heating the product
    • 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
    • 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
    • B21B45/04—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 de-scaling, e.g. by brushing
    • B21B45/08—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 de-scaling, e.g. by brushing hydraulically
    • 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
    • C22C38/008—Ferrous alloys, e.g. steel alloys containing tin
    • 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
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/46—Ferrous alloys, e.g. steel alloys containing chromium with nickel with vanadium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B27/00—Rolls, roll alloys or roll fabrication; Lubricating, cooling or heating rolls while in use
    • B21B27/06—Lubricating, cooling or heating rolls
    • B21B27/10—Lubricating, cooling or heating rolls externally
    • B21B2027/103—Lubricating, cooling or heating rolls externally cooling externally

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Metal Rolling (AREA)

Abstract

The invention relates to a method for producing ultrathin low-carbon steel by use of a thin slab casting and rolling process. The method comprises the following steps: continuously casting molten steel into a continuous cast billet with the width of 1,300-1,600 mm and the thickness of 60-100 mm; then sequentially conducting rough rolling, heat preservation by a heat holding cover, induction heating, high-pressure water phosphorus removal and finish rolling to obtain ultrathin strip steel with the width of 1,300-1,600 mm and the thickness of 0.8-1 mm; and finally, performing controlled cooling, roll-dividing cutting and roll take-up. A produced ultrathin low-carbon steel end product has the yield strength of 250-310 MPa, the tensile strength of 350-400 MPa and the ductility of larger than or equal to 35%. By adoption of the method, stable production of hot-rolled ultrathin low-carbon steel with the thickness of 0.8-1 mm can be realized, the dimensional accuracy, the flatness accuracy and the comprehensive mechanical property can be improved, the demand for 'replacement of cold product by hot product' is met and the production cost is lowered.

Description

A kind of method that application continuous casting and rolling technique of sheet bar produces ultra-thin mild steel
Technical field
The present invention relates to hot rolling technique field, more particularly, it relates to the production of one kind application continuous casting and rolling technique of sheet bar The method of ultra-thin mild steel.
Background technology
Both at home and abroad the technology path of the continuous casting and rolling technique of sheet bar of recent development is：Continuous casting-roughing-shearing-insulation-sense Should heat-de-scaling-finish rolling-control cools down-shears-batch.Compared with traditional continuous casting and rolling technique of sheet bar, the technique can The thinner hot-strip of production thickness, product is capable of achieving " with hot Dai Leng ", so as to reduce energy resource consumption and production to a greater degree Cost, therefore with wide market prospect.
At present 0.8～1mm can reach using the mild steel product thickness of this technique productions, the thickness range is low in hot rolling Ultra-thin specification is already belonging in carbon steel, the cold-rolled products of same specification can be substituted, be applied to the industries such as building, automobile and household electrical appliances, used In parts such as the various building elements of manufacture, container, panel, hood and casings.But using the technique productions, these are thin Following problem is still run into during specification mild steel：1st, each frame pressure unreasonable distribution causes certain frame to reach load pole Limit, makes the operation of rolling unstable；2nd, due to strip steel, continuously long-time is produced, and makes (the especially finishing mill work of each frame working roll Roller) wear and tear more serious, cause belt steel thickness precision and plate shape precision to be difficult to control to, occur that obvious thickness is overproof and shape wave； 3rd, quickly, belt steel temperature fluctuation is larger, makes target final rolling temperature hit rate relatively low, to band steel mechanical property for thin gauge strip temperature drop Have a negative impact.
What is solved the above problems it is critical only that the technique ginseng of the further ultra-thin mild steel of optimization CSP production Number, is included in continuous casting section and obtains appropriate sheet billet thickness and casting speed；Rational rolling rule are formulated in roughing and finish rolling section Journey (such as each frame reduction distribution, Calculating Rolling Force Energy Parameters and mill speed), the presetting optimum thickness of slab in the operation of rolling And Strip Shape Control parameter, so as to improve strip steel thickness of slab and plate shape feedback regulation efficiency；Joining section between roughing and finish rolling is formulated Strict insulation, heating and de-scaling system are controlling the belt steel temperature scope of each operation；Formulate rational cold in control cooling section But strip steel phase transformation during strategy and rate of cooling are to control cooling procedure, and then obtain preferable microstructure etc..
The content of the invention
The technical problem to be solved in the present invention is, there is provided one kind produces ultra-thin low-carbon (LC) using continuous casting and rolling technique of sheet bar The method of steel, can stably produce dimensional accuracy, plate shape precision and comprehensive mechanical property be satisfied by require hot ultrathin it is low Carbon steel.
The technical solution adopted for the present invention to solve the technical problems is：Construction one kind application continuous casting and rolling technique of sheet bar The method for producing ultra-thin mild steel, by molten steel direct casting into the continuous casting that width is 1300～1600mm, thickness is 60～100mm Base, then carry out successively roughing, thermal insulation cover insulation, sensing heating, high-pressure water descaling and finish rolling obtain width for 1300～ 1600mm, thickness are the ultrathin strip of 0.8～1mm, most after Jing control cooling, bundling shear and batch rolling.Main technique is walked Rapid and technological parameter is as follows：
(1) continuous casting
The ladle chemistry is by mass percentage：C 0.05%～0.1%, Si 0.01%～0.04%, Mn 0.08%～0.2%, Al 0.02%～0.04%, P≤0.015%, S≤0.01%, N≤0.006%, Ca≤0.0012%, Cu≤0.15%, Sn≤0.02%, Ni≤0.2%, Cr≤0.12%, Mo≤0.05%, V≤0.01%, remaining is for Fe and not Evitable trace element.
The casting speed of the continuous casting billet is 5.2～7m/min, and maximum casting speed vmaxWith thickness of strand h's Numerical relation meets：vmax=9.76 × 10-4h2-0.248h+20.25。
(2) roughing
The roughing mills are 3 frame roughing mills, and total reduction is 85%～90%, and roughing exit thickness is 9～11mm, Roughing initial temperature be 1140～1160 DEG C, roughing finishing temperature be 1010～1030 DEG C, unit width draught pressure be 14～ 17KN/mm。
(3) thermal insulation cover insulation
The thermal insulation cover length is 11m, and thermal insulation cover interior environment temperature is 500～550 DEG C.
(4) sensing heating
The induction heating apparatus includes 14 heaters, and each heater power is 2600～3000KW.Sensing heating Middle base temperature is set to raise 280～300 DEG C, base temperature is 1170～1190 DEG C in the middle of induction heating apparatus outlet.Computer is certainly Autocontrol system sets sensing heater and starts quantity and power according to the observed temperature of induction heater entrance pyrometer, according to The observed temperature of sensing heating outlet of still pyrometer adjusts sensing heater power, realizes base temperature in the middle of sensing heating outlet of still Feedback control.
(5) high-pressure water descaling
The high pressure water descaling device includes upper and lower two collectors, and 46 platypelloid type nozzles, nozzle are arranged on each collector Spacing is 35mm, and collector spraying width is 1720mm, and hydraulic pressure is 37～42MPa, and total water current amount is 170～190m3/ h, de-scaling makes Middle base surface temperature drop is 90～110 DEG C.Speed and descaling device porch of the computer automatic control system according to middle base The observed temperature of middle base adjusts hydraulic pressure and discharge.
(6) finish rolling
The mm finishing mill unit be 5 frame finishing mills, total reduction be 88%～93%, finish rolling exit thickness be 0.8～ 1mm, finish rolling initial temperature be 1010～1030 DEG C, finish rolling finishing temperature be 830～850 DEG C, unit width draught pressure be 8～ 20KN/mm。
(7) control cooling
The Controlled cooling process is first to carry out section cooling to strip steel, then air cooling.Specially：
The control cooling section includes 35 upper headers and 105 lower collector pipes, under the sprinkling zone of each upper header and 3 The sprinkling zone correspondence of collector.The flow of each upper header is 120～150m3/ h, the flow of each lower collector pipe is 40～50m3/ H, upper header spacing is 1110mm, and next part tube pitch is 370mm.
Computer automatic control system according to control cooling section strip steel at entry temperature, speed and thickness setting upper header and under The unlatching quantity of collector, and the discharge of upper header and lower collector pipe is carried out presetting, realize air cooling after strip steel elder generation section cooling Cooling technique.The upper header that deviation feedback regulation according to front belt steel temperature measured value and target coiling temperature is batched has turned on With the discharge of lower collector pipe.
The cooling section strip steel at entry temperature that controls for 810～840 DEG C, at the end of section cooling belt steel temperature be 600～ 630 DEG C, hydraulic pressure is 0.07～0.09MPa, and section cooling speed is 400～600 DEG C/s.The air cooling time is 3～5s.
(8) bundling is sheared and batched
The bundling shearing adopts rotary hub type flying shear, and the coiling machine is underground type coiling machine.Unit width volume weighs 20～ 22kg/mm, coiling temperature is 530～550 DEG C.
Longitudinal thickness deviation≤120 μm of the middle base, it is wide to convexity deviation C40≤60μm.The finished strip it is vertical To thickness deviation≤40 μm, plate shape deviation≤35I is wide to convexity deviation C40≤20μm.The surrender of the ultra-thin mild steel finished product Intensity be 250～310MPa, tensile strength be 350～400MPa, elongation percentage >=35%.
By such scheme, the thickness of strand is 75～85mm, and casting speed is 5.8～6.2m/min.
By such scheme, the first roughing mill reduction ratio of the roughing mills is 48%～52%, and rolling temperature control exists 1140～1160 DEG C, unit width draught pressure is 14.1～16KN/mm；Second roughing mill reduction ratio is 50%～55%, is rolled At 1075～1095 DEG C, unit width draught pressure is 15～16.5KN/mm to temperature control processed；3rd roughing mill reduction ratio is 45%～50%, at 1010～1030 DEG C, unit width draught pressure is 15.5～16.7KN/mm for rolling temperature control.
By such scheme, the first finishing mill reduction ratio of the mm finishing mill unit is 58%～62%, and rolling temperature control exists 1010～1030 DEG C, unit width draught pressure is 17～19KN/mm；Second finishing mill reduction ratio is 45%～50%, rolling At 960～980 DEG C, unit width draught pressure is 19～20KN/mm to temperature control；3rd finishing mill reduction ratio be 37%～ 43%, at 925～945 DEG C, unit width draught pressure is 16.5～18KN/mm for rolling temperature control；4th finishing mill is depressed Rate is 25%～30%, and at 880～900 DEG C, unit width draught pressure is 14～15.2KN/mm for rolling temperature control；5th Finishing mill reduction ratio is 10%～15%, and at 830～850 DEG C, unit width draught pressure is 8～8.7KN/ for rolling temperature control mm。
By such scheme, hydraulic AGC technology is adopted in roughing and mm finishing mill unit.Specially：Before rolling Roller gap preset is carried out, calibrator is exported according to the 3rd roughing mill in the operation of rolling and is surveyed thickness to middle base thickness feedback control System, surveys thickness and finished strip thickness feedback is controlled according to the 5th finishing mill outlet calibrator.Passed according to main hydraulic cylinder pressure Sensor measured value carries out roll-force overload protection.
By such scheme, the positive and negative roller technology of working roll is adopted in roughing mills, working roll is adopted in mm finishing mill unit Positive roller and working roll roll shifting technology.Specially：It is 900～1200KN on every side shaft holder that the positive bending roller force of roughing mill is, is born curved Roller power is that the finishing mill of mm finishing mill unit first, second is just for -1300～-1700KN (negative sign represents direction) on every side shaft holder Bending roller force is that for 1500～1700KN, working roll roll shifting scope is 100～120mm on every side shaft holder, the three, the 4th and the 5th It is 850～1000KN on every side shaft holder that the positive bending roller force of finishing mill is, working roll roll shifting scope is -180～-200mm (negative signs Represent direction).
By such scheme, working roll dynamic cooling technology is adopted in roughing and mm finishing mill unit.Specially：Working roll is moved State cooling includes main cooling, middle part supplement heat rejecter and edge supplement heat rejecter.Cooling water injection pressure is 0.8～1MPa, and each is thick The total cooling water inflow of mill stand is 1000～1200m3/ h, the total cooling water inflow of each finishing stand is 900～1000m3/h.By pre- Total cooling water inflow and ratio of three kinds of refrigerating modes of setting and regulation, to adjust each frame work roll thermal roll shape, and then reaches tune Section has the purpose for carrying Gap crown.
By such scheme, dynamic variable specification technology is adopted in mm finishing mill unit.Specially：Initially with 1.5mm thickness finished products The finish rolling rolling procedure of strip steel carries out threading and rolling, after producing the thick coil of strips of a 1.5mm, using the dynamic of mm finishing mill unit Become pressure and the mill speed of each finishing stand of specification function point analysis, finished strip thickness is changed to into 1.2mm from 1.5mm, produce After going out the thick coil of strip of 1.2mm, then 1mm is changed to by 1.2mm stably produce, if desired produce thinner finished strip, then Continue pressure and the mill speed for adjusting each finishing stand, then carry out stable production.The maximum that period, every time dynamic was adjusted Adjustment amount is 0.2mm, and finished strip is most thin can be adjusted to 0.8mm.Then entered by above-mentioned contrary mode by thin thickening during whipping OK.
By such scheme, roll gap lubrication technology is adopted in mm finishing mill unit.Specially：Each frame is used for roll gap lubrication Concentration of lubricating oil is 0.2%～0.4%, and injection flow is 5800～6300L/min, and injection pressure is 0.15～0.35MPa.
By such scheme, section cooling is located at control cooling section porch, and it is 3 that laminar flow cooling upper header opens quantity, The unlatching quantity of lower collector pipe is 12.The water flow set point of each upper header is 120～135m3/ h, the water of each lower collector pipe Flow setting value is 40～45m3/ h, section cooling hydraulic pressure is 0.08MPa.
Implement the method that the application continuous casting and rolling technique of sheet bar of the present invention produces ultra-thin mild steel, with following beneficial effect Really：
(1) under conditions of guarantee continuous casting billet not bleedout, the thickness and pulling rate of continuous casting billet are improved, so by increasing rolling Compression ratio can as far as possible eliminate the internal flaw of continuous casting billet, such as loose, crackle and segregation, and reaching improves the mesh of product mechanical property , additionally it is possible to rolled with higher speed, reduced rolled piece temperature drop, the finish rolling needed for being obtained with less energy medium consumption Finishing temperature and strip steel heterogeneous microstructure.
(2) by rolled piece temperature range at strict control each operation, to meet final rolling temperature requirement, finish rolling finish to gauge temperature is improved Degree targeting rate.By the rolling procedure (rolling temperature, reduction ratio and draught pressure) for optimizing roughing and each frame of finish rolling, subtract Few production accident rate.
(3) using efficient strip steel thickness of slab and Strip Shape Control technology in roughing and finishing stands, presetting optimum Technological parameter, and thickness of slab and plate shape are carried out feedback regulation to improve the control effect of thickness of slab and plate shape.
(4) yield strength of ultra-thin mild steel finished product obtained in is 250～310MPa, and tensile strength is 350～400MPa, Elongation percentage >=35%.The inventive method can realize the steady production of 0.8～1mm thickness hot ultrathin mild steel, and improve size Precision, plate shape precision and comprehensive mechanical property, realize " with hot Dai Leng " demand, reduce production cost.
Description of the drawings
Below in conjunction with drawings and Examples, the invention will be further described, in accompanying drawing：
Fig. 1 produces the process route of ultra-thin mild steel for the application continuous casting and rolling technique of sheet bar of the embodiment of the present invention one Figure；
Fig. 2 avoids continuous casting billet maximum pulling rate-thickness map under the conditions of bleedout for the embodiment of the present invention one；
Fig. 3 is the iron-carbon diagram that the phosphorus content of the embodiment of the present invention one is 0.05%～0.1% mild steel；
Fig. 4 is the control cooling section arrangement schematic diagram of the embodiment of the present invention one and embodiment three；
Fig. 5 controls cooling section phase transformation schematic diagram for the mild steel of the embodiment of the present invention one.
Specific embodiment
In order to be more clearly understood to the technical characteristic of the present invention, purpose and effect, now compare accompanying drawing and describe in detail The specific embodiment of the present invention.
Embodiment one：
A kind of application continuous casting and rolling technique of sheet bar that the present embodiment is provided produces the method for ultra-thin mild steel, its technique road Line as shown in figure 1, molten steel direct casting first is into the continuous casting billet that width is 1300～1600mm, thickness is 60～100mm, then Roughing, thermal insulation cover insulation, sensing heating, high-pressure water descaling and finish rolling are carried out successively obtains width for 1300～1600mm, thickness For the ultrathin strip of 0.8～1mm, most after Jing control coolings, bundling shear and batch rolling.Main technological steps and technological parameter It is as follows：
(1) continuous casting
The ladle chemistry is by mass percentage：C 0.05%～0.1%, Si 0.01%～0.04%, Mn 0.08%～0.2%, Al 0.02%～0.04%, P≤0.015%, S≤0.01%, N≤0.006%, Ca≤0.0012%, Cu≤0.15%, Sn≤0.02%, Ni≤0.2%, Cr≤0.12%, Mo≤0.05%, V≤0.01%, remaining is for Fe and not Evitable trace element.
The casting speed of the continuous casting billet is 5.2～7m/min, and maximum casting speed vmaxWith thickness of strand h's Numerical relation meets：vmax=9.76 × 10-4h2-0.248h+20.25。
Continuous casting billet maximum casting speed with the numerical relation of thickness to avoid continuous casting billet bleedout from setting up as principle, roll by satisfaction The continuous casting billet minimum thickness that compression ratio processed is required is 60mm, and the minimum pulling rate of finishing temperature needed for meeting is 5.2m/min, is met The maximum pulling rate of design for continuous casting machine ability is 7m/min, by minimum pulling rate and avoids the continuous casting billet maximum pulling rate-thickness of bleedout bent The continuous casting billet maximum gauge that line determines is 100mm.As shown in Fig. 2 the coordinate points of thickness of strand and casting speed composition need to fall In fig. 2 in ABCD regional extents, continuous casting billet in such range has 3 advantages：1st, can directly be rolled and not Continuous casting billet bleedout accident occurs；2nd, enough rolling reductions are can ensure that, to eliminate the internal flaw of continuous casting billet, is such as dredged Pine, crackle and segregation etc., so as to improve product mechanical property；3rd, can be rolled with higher speed, be reduced rolled piece temperature drop And energy consumption, the finish rolling finishing temperature and strip steel heterogeneous microstructure needed for obtaining.
(2) roughing
The roughing mills are 3 frame roughing mills, and total reduction is 85%～90%, and roughing exit thickness is 9～11mm, Roughing exit thickness is 9～11mm, and roughing initial temperature is 1140～1160 DEG C, and roughing finishing temperature is 1010～1030 DEG C, Unit width draught pressure is 14～17KN/mm.
It can be seen from the carbon iron balance phasor shown in Fig. 3, for the mild steel that phosphorus content is 0.05%～0.1%, roughing When initial temperature is 1140～1160 DEG C, the middle temperature province of mild steel austenitic area is located substantially at, now in continuous casting billet Portion is that high temperature austenite tissue, coarse grains, and carbide are dissolved completely in austenite structure, is very suitable for the big pressure of roughing Lower amount rolling.After 3 frame roughing mills, due to rolled piece heat radiation temperature drop, rolled piece and working roll contact heat conductien temperature drop and The comprehensive function of rolled piece temperature rise caused by rolling plastic deformation heat and frictional heat so that roughing finishing temperature still may remain in 1010～1030 DEG C, the temperature range is located substantially at ferrite and starts more than transformation line 100～160 DEG C, due in rough rolling process The effect of dynamic recrystallization, makes the middle base inside austenite crystal that roughing is obtained become tiny isometry.
Due to high in roughing section rolled piece mean temperature, and the thick Temperature Distribution upwards of slab be " reverse temperature curve " (just Just the slab central temperature specific surface temperature of solidification is high 100～150 DEG C), resistance of deformation very little, deformation is concentrated mainly in slab Portion, therefore roughing mill can carry out heavy reduction rolling with relatively low energy consumption.Calculated by hot-rolling draught pressure energy parameter model Unit width draught pressure is 14～17KN/mm, and contact stress is 1366～1505MPa between corresponding roller, less than roll for hot-rolling Contact stress 1800MPa between maximum allowable roller, can cause the roll wear of rolling unit length rolled piece little, it is also possible to avoid because The caused spalling of rolls of contact stress and thermal stress superposition between roller, therefore work roll cooling cycle and rolling tonnage can be improved.
Roughing section total reduction is 85%～90%, is existed equivalent to 88%～90% from continuous casting billet to finished product overall reduction Roughing section is completed, and finish rolling section only completes the 10%～12% of overall reduction, can reduce the high load capacity to follow-up mm finishing mill unit Require, be conducive to mm finishing mill unit to be absorbed in the control to belt steel thickness precision, plate shape precision and surface quality.In addition, thickness is 9 The middle base accumulation of heat effect of～11mm preferably, ensure that temperature drop and head and tail temperature difference of the middle base on delay table all without too Greatly, the concurrent heating burden of follow-up induction heater is reduced, with reducing energy consumption.
(3) thermal insulation cover insulation
The thermal insulation cover length is 11m, and thermal insulation cover interior environment temperature is 500～550 DEG C, can effectively reduce middle base and exist Temperature drop on delay table, reduces the concurrent heating burden of follow-up sensing heating.
(4) sensing heating
The induction heating apparatus includes 14 heaters, and each heater power is 2600～3000KW.Sensing heating Middle base temperature is set to raise 280～300 DEG C, base temperature is 1170～1190 DEG C in the middle of induction heating apparatus outlet.Computer is certainly Autocontrol system sets sensing heater and starts quantity and power according to the observed temperature of induction heater entrance pyrometer, according to The observed temperature of sensing heating outlet of still pyrometer adjusts sensing heater power, is capable of achieving base temperature in the middle of sensing heating outlet of still The feedback control of degree.
(5) high-pressure water descaling
The high pressure water descaling device includes upper and lower two collectors, and 46 platypelloid type nozzles, nozzle are arranged on each collector Spacing is 35mm, and collector spraying width is 1720mm, and hydraulic pressure is 37～42MPa, and total water current amount is 170～190m3/ h, de-scaling makes Middle base surface temperature drop is 90～110 DEG C.Speed and descaling device porch of the computer automatic control system according to middle base The observed temperature of middle base adjusts hydraulic pressure and discharge, it is ensured that can effectively remove middle base scale on surface, prevent finish rolling When surface scale press-in strip steel, can make temperature drop of the middle base during de-scaling less again, maintain higher finish rolling section entrance Belt steel temperature.
(6) finish rolling
The mm finishing mill unit be 5 frame finishing mills, total reduction be 88%～93%, finish rolling exit thickness be 0.8～ 1mm, finish rolling initial temperature be 1010～1030 DEG C, finish rolling finishing temperature be 830～850 DEG C, unit width draught pressure be 8～ 20KN/mm。
Middle base is entered after mm finishing mill unit with the finish rolling initial temperature, peels off cold between water cooling, frame because roll is anti- But the comprehensive function of water cooling, heat radiation, strip steel and roll contact conduction of heat, plastic deformation heat and frictional heat, the total body temperature of strip steel Drop is maintained at 160～200 DEG C, and required strip finishing temperature can be met after temperature drop, is microcosmic in follow-up laminar cooling process Structural transformation is prepared.In addition, the finish rolling section temperature range can ensure that strip steel is rolled all the time in austenitic area, it is to avoid finish rolling Shi Fasheng austenites are changed into ferrite, if otherwise rolling in austenite and ferrite two-phase section, strip steel Mechanical Fluctuation It is unstable compared with rolling is made greatly, and banded structure and uneven mixed grain structure can be produced, make band steel mechanical property and processability Can deteriorate.
(7) control cooling
The Controlled cooling process is first to carry out section cooling to strip steel, then air cooling.Specially：
As shown in figure 4, the control cooling section includes 35 upper headers and 105 lower collector pipes, the water spray of each upper header Region is corresponding with the sprinkling zone of 3 lower collector pipes, and the flow of each upper header is 120～150m3/ h, the maximum of each lower collector pipe Flow is 40～50m3/ h, upper header spacing is 1110mm, and next part tube pitch is 370mm.Due to being ejected into strip steel lower surface Cooling water is dripped quickly under gravity, it is impossible to which the cooling water of image-tape steel upper surface flows like that, therefore be arranged so as to can be with Refinement strip steel lower surface cooling water sprinkling zone, strip steel upper and lower surface is uniformly cooled down, it is to avoid thin gauge strip cool down when to Upper warpage.
Computer automatic control system according to control cooling section strip steel at entry temperature, speed and thickness setting upper header and under The unlatching quantity of collector, and the discharge of upper header and lower collector pipe is carried out presetting, realize air cooling after strip steel elder generation section cooling Cooling technique.The upper header that deviation feedback regulation according to front belt steel temperature measured value and target coiling temperature is batched has turned on With the discharge of lower collector pipe, to adjust laminar flow rate of cooling, the accurate hit coiling temperature of actual coiling temperature is made.
The cooling section strip steel at entry temperature that controls for 810～840 DEG C, at the end of section cooling belt steel temperature be 600～ 630 DEG C, hydraulic pressure is 0.07～0.09MPa, and section cooling speed is 400～600 DEG C/s.The air cooling time is 3～5s.
As shown in figure 5, section cooling makes strip steel be cooled fast to ferrite transformation temperature interval, the part in subsequent air cooling Cooling Austenite Transformation is ferrite, and as belt steel temperature is further reduced, remaining Cooling Austenite Transformation is pearlite.Most The line and staff control of ferrite and pearlite is obtained eventually.
(8) bundling is sheared and batched
The bundling shearing adopts rotary hub type flying shear, and the coiling machine is underground type coiling machine.Unit width volume weighs 20～ 22kg/mm, coiling temperature is 530～550 DEG C, is batched in the temperature range, after can both having avoided that coiling temperature is too high and causing Band crystalline grain of steel is grown up during continuous slow cooling, while can also separate out tiny, Dispersed precipitate carbide, improves the comprehensive of ultra-thin mild steel finished product Close mechanical property.
Embodiment two：
The present embodiment provide on the basis of embodiment one it is a kind of in further detail, optimization process program, finished product can be made Strip steel longitudinal thickness precision, plate shape precision and surface quality more preferably, and obtain the comprehensive mechanics suitable with same specification cold-strip steel Performance.
The thickness of strand is 75～85mm, and casting speed is 5.8～6.2m/min.
First roughing mill reduction ratio of the roughing mills is 48%～52%, and rolling temperature is controlled 1140～1160 DEG C, unit width draught pressure is 14.1～16KN/mm；Second roughing mill reduction ratio is 50%～55%, rolling temperature control At 1075～1095 DEG C, unit width draught pressure is 15～16.5KN/mm；3rd roughing mill reduction ratio is 45%～50%, At 1010～1030 DEG C, unit width draught pressure is 15.5～16.7KN/mm for rolling temperature control.
First finishing mill reduction ratio of the mm finishing mill unit is 58%～62%, and rolling temperature is controlled 1010～1030 DEG C, unit width draught pressure is 17～19KN/mm；Second finishing mill reduction ratio is 45%～50%, and rolling temperature control exists 960～980 DEG C, unit width draught pressure is 19～20KN/mm；3rd finishing mill reduction ratio is 37%～43%, rolling temperature At 925～945 DEG C, unit width draught pressure is 16.5～18KN/mm for degree control；4th finishing mill reduction ratio be 25%～ 30%, at 880～900 DEG C, unit width draught pressure is 14～15.2KN/mm for rolling temperature control；5th finishing mill is depressed Rate is 10%～15%, and at 830～850 DEG C, unit width draught pressure is 8～8.7KN/mm for rolling temperature control.
Permanent gap preset is carried out to each frame using hydraulic AGC technology in roughing and mm finishing mill unit, with The thickness fluctuation of continuous casting billet and middle base is effectively eliminated, middle base and finished strip longitudinal thickness precision is improved.Specially：Rolling Before carry out roller gap preset, in the operation of rolling according to the 3rd roughing mill export calibrator survey thickness to middle base thickness feedback control System, surveys thickness and finished strip thickness feedback is controlled according to the 5th finishing mill outlet calibrator.Passed according to main hydraulic cylinder pressure Sensor measured value carries out roll-force overload protection.
Using base convexity in the middle of the positive and negative roller technical controlling of working roll in roughing mills, work is adopted in mm finishing mill unit Make the positive roller of roller and working roll roll shifting technical controlling finished strip plate shape.Specially：The positive bending roller force of roughing mill is every side shaft holder Upper is 900～1200KN, and negative bending roller force is for -1300～-1700KN (negative sign represents direction), mm finishing mill unit on every side shaft holder The positive bending roller force of first, second finishing mill is on every side shaft holder that working roll roll shifting scope is 100 for 1500～1700KN～ The positive bending roller force of the finishing mills of 120mm, the three, the 4th and the 5th is for 850～1000KN, working roll roll shifting model on every side shaft holder Enclose for -180～-200mm (negative sign represents direction).
Using base convexity and completed belt steel plate in the middle of working roll dynamic cooling technical controlling in roughing and mm finishing mill unit Shape.Specially：Working roll dynamic cooling includes main cooling, middle part supplement heat rejecter and edge supplement heat rejecter.Wherein, main cooling is realized The constant cooldown rate of the working roll body of roll, middle part supplement heat rejecter is used to carry out additional cooling to body of roll middle part to obtain convex roll gap song Line, edge supplement heat rejecter is used to carry out body of roll edge additional cooling to obtain recessed roll gap curve.Cooling water injection pressure is 0.8 ～1MPa, the total cooling water inflow of each pony roughing mill is 1000～1200m3/ h, the total cooling water inflow of each finishing stand be 900～ 1000m3/h.By total cooling water inflow and ratio presetting and that adjust three kinds of refrigerating modes, to adjust each frame work roll thermal Roll shape, so reach adjust have carry Gap crown purpose.
" boiling hot roller " is carried out using dynamic variable specification technology in mm finishing mill unit, needed for can rapidly obtaining rolling ultrathin strip Stable work roll thermal roll shape and complete fine and close work roll surface oxide-film.Specially：Initially with 1.5mm thickness completed belt The finish rolling rolling procedure of steel carries out threading and rolling, after producing the thick coil of strips of a 1.5mm, is become using the dynamic of mm finishing mill unit The pressure of each finishing stand of specification function point analysis and mill speed, 1.2mm is changed to by finished strip thickness from 1.5mm, is produced After one 1.2mm thick coil of strip, then 1mm changed to by 1.2mm stably produce, if desired produce thinner finished strip, then after The continuous pressure for adjusting each finishing stand and mill speed, then carry out stable production.Period, every time the maximum of dynamic adjustment was adjusted Whole amount is 0.2mm, and finished strip is most thin can be adjusted to 0.8mm.Then entered by above-mentioned contrary mode by thin thickening during whipping OK.
The coefficient of friction between working roll and strip steel is reduced using roll gap lubrication technology in mm finishing mill unit, to reduce rolling energy Consumption and working roller abrasion, improve strip surface quality and working roll service life.Specially：Each frame is used for roll gap lubrication Concentration of lubricating oil is 0.2%～0.4%, and injection flow is 5800～6300L/min, and injection pressure is 0.15～0.35MPa.
As shown in figure 4, section cooling is located at control cooling section porch, it is 3 that laminar flow cooling upper header opens quantity, under The unlatching quantity of collector is 12.The water flow set point of each upper header is 120～135m3/ h, the current of each lower collector pipe Amount setting value is 40～45m3/ h, section cooling hydraulic pressure is 0.08MPa.
Longitudinal thickness deviation≤120 μm of the middle base obtained using the present embodiment method, it is wide to convexity deviation C40≤60μ m.Longitudinal thickness deviation≤40 μm of finished strip, plate shape deviation≤35I is wide to convexity deviation C40≤25μm.Ultra-thin mild steel The Main Mechanical of finished product is all fallen within following scope：Yield strength be 250～310MPa, tensile strength be 350～ 400MPa, elongation percentage >=35%.The cold-strip steel of same specification can be well substituted in application.
Embodiment three：
As a example by the present embodiment is to produce phosphorus content 0.06%, width 1600mm, the finished strip of thickness 0.8mm, its is concrete Technique is as described below.
Then molten steel direct casting carries out successively roughing, thermal insulation cover into the continuous casting billet that width is 1600mm, thickness is 80mm Insulation, sensing heating, high-pressure water descaling and finish rolling obtain width for 1600mm, thickness for 0.8mm ultrathin strip, most after Jing control Refrigeration but, bundling shear and batch rolling.Main technological steps and technological parameter are as follows：
(1) continuous casting
The ladle chemistry is by mass percentage：C 0.06%, Si 0.01%～0.04%, Mn 0.08%～ 0.2%th, Al 0.02%～0.04%, P≤0.015%, S≤0.01%, N≤0.006%, Ca≤0.0012%, Cu≤ 0.15%th, Sn≤0.02%, Ni≤0.2%, Cr≤0.12%, Mo≤0.05%, V≤0.01%, remaining is Fe and can not keep away The trace element exempted from.
The casting speed of the continuous casting billet is 6m/min.
(2) roughing
The roughing mills are 3 frame roughing mills, and total reduction is 87.5%, and roughing exit thickness is 10mm, at the beginning of roughing Beginning temperature be 1145～1155 DEG C, roughing finishing temperature be 1015～1025 DEG C, unit width draught pressure be 14.3～ 16.6KN/mm。
(3) thermal insulation cover insulation
The thermal insulation cover length is 11m, and thermal insulation cover interior environment temperature is 550 DEG C.
(4) sensing heating
The induction heating apparatus includes 14 heaters, and each heater power is 2800～2900KW.Sensing heating Middle base temperature is set to raise 290～300 DEG C, base temperature is 1175～1185 DEG C in the middle of induction heating apparatus outlet.Computer is certainly Autocontrol system sets sensing heater and starts quantity and power according to the observed temperature of induction heater entrance pyrometer, according to The observed temperature of sensing heating outlet of still pyrometer adjusts sensing heater power, realizes base temperature in the middle of sensing heating outlet of still Feedback control.
(5) high-pressure water descaling
The high pressure water descaling device includes upper and lower two collectors, and 46 platypelloid type nozzles, nozzle are arranged on each collector Spacing is 35mm, and collector spraying width is 1720mm, and hydraulic pressure is 40MPa, and total water current amount is 180m3/ h, de-scaling makes middle base table Face temperature drop is 92～97 DEG C.Computer automatic control system is according to the speed of middle base and the reality of descaling device porch centre base Testing temperature adjusts hydraulic pressure and discharge.
(6) finish rolling
The mm finishing mill unit is 5 frame finishing mills, and total reduction is 92%, and finish rolling exit thickness is 0.8mm, and finish rolling is initial Temperature is 1015～1025 DEG C, and finish rolling finishing temperature is 840～850 DEG C, and unit width draught pressure is 8.1～20KN/mm.
(7) control cooling
The Controlled cooling process is first to carry out section cooling to strip steel, then air cooling.Specially：
The control cooling section includes 35 upper headers and 105 lower collector pipes, under the sprinkling zone of each upper header and 3 The sprinkling zone correspondence of collector.The maximum stream flow of each upper header is 120～135m3/ h, the maximum stream flow of each lower collector pipe is 40～45m3/ h, upper header spacing is 1110mm, and next part tube pitch is 370mm.
Computer automatic control system according to control cooling section strip steel at entry temperature, speed and thickness setting upper header and under The unlatching quantity of collector, and the discharge of upper header and lower collector pipe is carried out presetting, realize air cooling after strip steel elder generation section cooling Cooling technique.The upper header that deviation feedback regulation according to front belt steel temperature measured value and target coiling temperature is batched has turned on With the discharge of lower collector pipe.
The cooling section strip steel at entry temperature that controls for 825～835 DEG C, at the end of section cooling belt steel temperature be 610～ 620 DEG C, hydraulic pressure is 0.08MPa, and section cooling speed is 520～540 DEG C/s.The air cooling time is 4s.
(8) bundling is sheared and batched
The bundling shearing adopts rotary hub type flying shear, and the coiling machine is underground type coiling machine.Unit width rolls up weight 21kg/mm, coiling temperature is 540～550 DEG C.
By such scheme, the first roughing mill reduction ratio of the roughing mills is 50%, rolling temperature control 1145～ 1155 DEG C, unit width draught pressure is 14.3～14.5KN/mm；Second roughing mill reduction ratio is 52.5%, rolling temperature control At 1080～1090 DEG C, unit width draught pressure is 15.8～16.1KN/mm to system；3rd roughing mill reduction ratio is 47.4%, At 1015～1025 DEG C, unit width draught pressure is 16.4～16.6KN/mm for rolling temperature control.
By such scheme, the first finishing mill reduction ratio of the mm finishing mill unit is 60%, rolling temperature control 1015～ 1025 DEG C, unit width draught pressure is 18.4～18.7KN/mm；Second finishing mill reduction ratio is 47.5%, rolling temperature control At 965～975 DEG C, unit width draught pressure is 19.8～20KN/mm to system；3rd finishing mill reduction ratio is 40%, rolling temperature At 935～945 DEG C, unit width draught pressure is 17.3～17.6KN/mm for degree control；4th finishing mill reduction ratio is 28%, At 890～900 DEG C, unit width draught pressure is 14.8～15.1KN/mm for rolling temperature control；5th finishing mill reduction ratio is 11.1%, at 840～850 DEG C, unit width draught pressure is 8.1～8.4KN/mm for rolling temperature control.
By such scheme, hydraulic AGC technology is adopted in roughing and mm finishing mill unit.Specially：Before rolling Roller gap preset is carried out, calibrator is exported according to the 3rd roughing mill in the operation of rolling and is surveyed thickness to middle base thickness feedback control System, surveys thickness and finished strip thickness feedback is controlled according to the 5th finishing mill outlet calibrator.Passed according to main hydraulic cylinder pressure Sensor measured value carries out roll-force overload protection.
By such scheme, the positive and negative roller technology of working roll is adopted in roughing mills, working roll is adopted in mm finishing mill unit Positive roller and working roll roll shifting technology.Design parameter is as shown in table 1：
Table 1
By such scheme, working roll dynamic cooling technology is adopted in roughing and mm finishing mill unit.Specially：Working roll is moved State cooling includes main cooling, middle part supplement heat rejecter and edge supplement heat rejecter.Cooling water injection pressure is 0.9MPa, each frame work Roller cooling water total flow, each refrigerating mode cooling water flow ratio and flow pre-set value are as shown in table 2, by presetting and tune Total cooling water inflow and ratio of three kinds of refrigerating modes of section, has load roller to adjust each frame work roll thermal roll shape, and then reach regulation The purpose of seam convexity.
Table 2
By such scheme, dynamic variable specification technology is adopted in mm finishing mill unit.Specially：Initially with 1.5mm thickness finished products The finish rolling rolling procedure of strip steel carries out threading and rolling, after producing the thick coil of strips of a 1.5mm, using the dynamic of mm finishing mill unit Become pressure and the mill speed of each finishing stand of specification function point analysis, finished strip thickness is changed to into 1.2mm from 1.5mm, produce After going out the thick coil of strips of a 1.2mm, then 1mm one coils of production are changed to by 1.2mm, then 0.9mm are changed to from 1mm and produce a coil, Finally change to steady production after 0.8mm from 0.9mm.Then carried out by above-mentioned contrary mode by thin thickening during whipping.
By such scheme, roll gap lubrication technology is adopted in mm finishing mill unit.Specially：Each frame is used for roll gap lubrication Concentration of lubricating oil is 0.35%, and injection flow is 6000L/min, and injection pressure is 0.3MPa.
By such scheme, section cooling is located at control cooling section porch, and it is 3 that laminar flow cooling upper header opens quantity, The unlatching quantity of lower collector pipe is 12.The water flow set point of each upper header is 126m3/ h, the discharge of each lower collector pipe sets Definite value is 42m3/ h, section cooling hydraulic pressure is 0.08MPa.
Longitudinal thickness deviation≤25 μm of the finished strip of the 0.8mm thickness obtained using the present embodiment method, plate shape deviation ≤ 20I, it is wide to convexity deviation C40≤15μm.Yield strength be 276～285MPa, tensile strength be 351～363MPa, elongation percentage For 36～39%.
Embodiments of the invention are described above in conjunction with accompanying drawing, but be the invention is not limited in above-mentioned concrete Embodiment, above-mentioned specific embodiment is only schematic, rather than restricted, one of ordinary skill in the art Under the enlightenment of the present invention, in the case of without departing from present inventive concept and scope of the claimed protection, can also make a lot Form, these are belonged within the protection of the present invention.

Claims (10)

1. a kind of method that application continuous casting and rolling technique of sheet bar produces ultra-thin mild steel, it is characterised in that comprise the following steps：
(1) prepare molten steel, the molten steel includes following components, by mass percentage for：C 0.05%～0.1%, Si 0.01% ～0.04%, Mn 0.08%～0.2%, Al 0.02%～0.04%, P≤0.015%, S≤0.01%, N≤0.006%, Ca≤0.0012%, Cu≤0.15%, Sn≤0.02%, Ni≤0.2%, Cr≤0.12%, Mo≤0.05%, V≤0.01%, Remaining is Fe and inevitable trace element；By molten steel direct casting into width be 1300～1600mm, thickness be 60～ The continuous casting billet of 100mm, the casting speed of the continuous casting billet is 5.2～7m/min, and maximum casting speed vmaxIt is thick with continuous casting billet The numerical relation of degree h meets：vmax=9.76 × 10-4h2-0.248h+20.25；
(2) roughing is carried out, roughing mills are 3 frame roughing mills, total reduction is 85%～90%, roughing exit thickness is 9～ 11mm, roughing initial temperature is 1140～1160 DEG C, and roughing finishing temperature is 1010～1030 DEG C, and unit width draught pressure is 14～17KN/mm；
(3) it is incubated in thermal insulation cover, thermal insulation cover interior environment temperature is 500～550 DEG C；
(4) sensing heating is carried out by induction installation, makes middle base temperature raise 280～300 DEG C, in induction heating apparatus outlet Between base temperature be 1170～1190 DEG C；
(5) high-pressure water descaling is carried out by high pressure water descaling device；
(6) finish rolling is carried out, mm finishing mill unit is 5 frame finishing mills, and total reduction is 88%～93%, and finish rolling exit thickness is 0.8 ～1mm, finish rolling initial temperature is 1010～1030 DEG C, and finish rolling finishing temperature is 830～850 DEG C, and unit width draught pressure is 8 ～20KN/mm；The ultrathin strip that width is 1300～1600mm, thickness is 0.8～1mm is obtained after finish rolling；
(7) section cooling being carried out to strip steel in control cooling section, then carries out air cooling, cooling section strip steel at entry temperature is 810～ 840 DEG C, belt steel temperature is 600～630 DEG C at the end of section cooling, and section cooling speed is 400～600 DEG C/s；Air cooling time For 3～5s；
(8) bundling is sheared and batched.
2. the method that application continuous casting and rolling technique of sheet bar according to claim 1 produces ultra-thin mild steel, its feature exists In the high pressure water descaling device includes upper and lower two collectors, and 46 platypelloid type nozzles are arranged on each collector, and injector spacing is 35mm, collector spraying width is 1720mm, and hydraulic pressure is 37～42MPa, and total water current amount is 170～190m3/ h, de-scaling makes middle base Surface temperature drop is 90～110 DEG C.
3. the method that application continuous casting and rolling technique of sheet bar according to claim 1 produces ultra-thin mild steel, its feature exists In the control cooling section includes 35 upper headers and 105 lower collector pipes, the sprinkling zone of each upper header and 3 lower collector pipes Sprinkling zone correspondence, the flow of each upper header is 120～150m3/ h, the flow of each lower collector pipe is 40～50m3/ h, on Integrate tube pitch as 1110mm, next part tube pitch is 370mm, and computer automatic control system is according to control cooling section strip steel at entry temperature Degree, speed and thickness set respectively the upper header of control cooling entrance and the unlatching quantity of lower collector pipe, and to upper header with The discharge of collector carry out it is presetting, according to the deviation feedback regulation for batching front belt steel temperature measured value and target coiling temperature The upper header of unlatching and the discharge of lower collector pipe.
4. the method that application continuous casting and rolling technique of sheet bar according to claim 1 produces ultra-thin mild steel, its feature exists In the bundling shearing adopts rotary hub type flying shear, and the coiling machine is underground type coiling machine；Unit width volume weighs 20～22kg/ Mm, coiling temperature is 530～550 DEG C.
5. the method that application continuous casting and rolling technique of sheet bar according to claim 1 produces ultra-thin mild steel, its feature exists In the thickness of strand is 75～85mm, and casting speed is 5.8～6.2m/min.
6. the method that application continuous casting and rolling technique of sheet bar according to claim 1 produces ultra-thin mild steel, its feature exists In the first roughing mill reduction ratio of, roughing mills be 48%～52%, rolling temperature control at 1140～1160 DEG C, unit Width draught pressure is 14.1～16KN/mm；Second roughing mill reduction ratio is 50%～55%, rolling temperature control 1075～ 1095 DEG C, unit width draught pressure is 15～16.5KN/mm；3rd roughing mill reduction ratio is 45%～50%, rolling temperature At 1010～1030 DEG C, unit width draught pressure is 15.5～16.7KN/mm for control.
7. the method that application continuous casting and rolling technique of sheet bar according to claim 1 produces ultra-thin mild steel, its feature exists In the first finishing mill reduction ratio is 58%～62%, and at 1010～1030 DEG C, unit width rolling is pressed for rolling temperature control Power is 17～19KN/mm；Second finishing mill reduction ratio is 45%～50%, rolling temperature control at 960～980 DEG C, unit width Degree draught pressure is 19～20KN/mm；3rd finishing mill reduction ratio is 37%～43%, and rolling temperature is controlled 925～945 DEG C, unit width draught pressure is 16.5～18KN/mm；4th finishing mill reduction ratio is 25%～30%, rolling temperature control At 880～900 DEG C, unit width draught pressure is 14～15.2KN/mm；5th finishing mill reduction ratio is 10%～15%, is rolled At 830～850 DEG C, unit width draught pressure is 8～8.7KN/mm to temperature control processed.
8. the method that application continuous casting and rolling technique of sheet bar according to claim 1 produces ultra-thin mild steel, its feature exists In, hydraulic AGC is adopted in roughing and mm finishing mill unit, roller gap preset is carried out before the rolling, in the operation of rolling Calibrator actual measurement thickness is exported according to the 3rd roughing mill to control middle base thickness feedback, according to the 5th finishing mill outlet calibrator Actual measurement thickness is controlled finished strip thickness feedback.Roll-force overload is carried out according to main hydraulic cylinder pressure sensor measurements to protect Shield.
9. the method that application continuous casting and rolling technique of sheet bar according to claim 1 produces ultra-thin mild steel, its feature exists In, the positive and negative roller technique of working roll is adopted in roughing mills, altered using the positive roller of working roll and working roll in mm finishing mill unit Roller technique, the positive bending roller force of roughing mill be on every side shaft holder for 900～1200KN, negative bending roller force be on every side shaft holder for- 1300～-1700KN, it is 1500～1700KN on every side shaft holder that the positive bending roller force of the finishing mill of mm finishing mill unit first, second is, Working roll roll shifting scope is 100～120mm, and the positive bending roller force of the 3rd finishing mill, the 4th finishing mill and the 5th finishing mill is every side It is 850～1000KN on bearing block, working roll roll shifting scope is -180～-200mm.
10. the method that application continuous casting and rolling technique of sheet bar according to claim 1 produces ultra-thin mild steel, its feature exists In auxiliary using working roll dynamic cooling, including main cooling, middle part supplement heat rejecter and edge in roughing mills and mm finishing mill unit Cooling is helped, cooling water injection pressure is 0.8～1MPa, and the total cooling water inflow of each pony roughing mill is 1000～1200m3/ h, each The total cooling water inflow of finishing stand is 900～1000m3/h。
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CN107597845A (en) * 2017-10-16 2018-01-19 北京科技大学 Ultra-low carbon coil of strip ferrite rolling method and apparatus are used in the punching of endless casting rolling ultra-deep
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005095926A (en) * 2003-09-24 2005-04-14 Kawasaki Heavy Ind Ltd Continuous casting and hot-rolling apparatus, and continuous casting and hot-rolling method
CN1676233A (en) * 2005-05-20 2005-10-05 唐山钢铁股份有限公司 Sheet slab C-Mn excellent high-strength sheet-band steel production process
CN101293257A (en) * 2007-04-25 2008-10-29 宝山钢铁股份有限公司 Process for manufacturing hot rolled steel strips by using compaction type continuous casting and rolling technique
CN101293259A (en) * 2008-06-12 2008-10-29 湖南华菱涟源钢铁有限公司 Method for producing variable-specification/constant-specification ultrathin hot-rolled strip steel by adopting semi-endless technology
CN103014496A (en) * 2012-12-06 2013-04-03 武汉钢铁(集团)公司 High-strength hot-rolled steel strip with thickness ranging from 1.1 to 2 mm and easy to form
CN103878178A (en) * 2014-03-04 2014-06-25 河北钢铁股份有限公司唐山分公司 Method for producing ultrathin hot-rolled coils from sheet billets by continuous casting and rolling

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005095926A (en) * 2003-09-24 2005-04-14 Kawasaki Heavy Ind Ltd Continuous casting and hot-rolling apparatus, and continuous casting and hot-rolling method
CN1676233A (en) * 2005-05-20 2005-10-05 唐山钢铁股份有限公司 Sheet slab C-Mn excellent high-strength sheet-band steel production process
CN101293257A (en) * 2007-04-25 2008-10-29 宝山钢铁股份有限公司 Process for manufacturing hot rolled steel strips by using compaction type continuous casting and rolling technique
CN101293259A (en) * 2008-06-12 2008-10-29 湖南华菱涟源钢铁有限公司 Method for producing variable-specification/constant-specification ultrathin hot-rolled strip steel by adopting semi-endless technology
CN103014496A (en) * 2012-12-06 2013-04-03 武汉钢铁(集团)公司 High-strength hot-rolled steel strip with thickness ranging from 1.1 to 2 mm and easy to form
CN103878178A (en) * 2014-03-04 2014-06-25 河北钢铁股份有限公司唐山分公司 Method for producing ultrathin hot-rolled coils from sheet billets by continuous casting and rolling

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