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
  • C21D9/52—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
  • C21D9/573—Continuous furnaces for strip or wire with cooling
• • 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
  • C21D8/0252—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment with application of tension
• • 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
  • C21D1/667—Quenching devices for spray 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
  • C21D11/00—Process control or regulation for heat treatments
  • C21D11/005—Process control or regulation for heat treatments for cooling

Definitions

• the invention relates to a method and a device for controlled straightening and cooling of wide metal strip, in particular steel strip or sheet metal, emerging from a hot strip rolling mill, using squeezing rollers arranged in the direction of strip travel behind vertical double rollers, which produce a tensile stress acting in the longitudinal direction.
• the method described above and the device are essentially known from DE 33 13 024 A1.
• This is a method and an apparatus for quenching continuous steel sheets, in particular heavy and medium-sized sheets, with simultaneous controlled straightening, in which the sheets are quenched in the warm state by at least two vertical double rollers arranged in a row in one plane be aligned. The sheet is then pulled by a quenching device under controlled tension from at least one double roller.
• the aim of this process is to scour continuous steel sheets exactly to the predetermined mechanical properties without them warping or warping, while at the same time reducing unevenness that is already present.
• the invention has for its object to expand the field of application of conventional sheet metal cooling systems to higher flatness of the sheet with increased cooling effect.
• the object is achieved according to the invention in that the metal strip or the sheet is displaced between a pre-straightening machine and a spray cooling under defined tensile stresses by regulating the tensile stress and that cooling is carried out between successive pinch roller pairs within the spray cooling and additionally controls the tensile stress becomes.
• This causes a plastic deformation immediately before the metal strip or sheet enters the cooling system.
• the plastic deformation reduces the incoming unevenness of the metal strip or sheet.
• Another advantage is the direct arrangement of the straightening process before cooling, which prevents the re-build-up of residual stresses and deformations due to the uneven cooling on the surface of the metal strip or sheet.
• the cooling effect is practically limited by the induction of stresses and related deformations in the sheet, due to the non-uniform cooling effect of the cooling medium (water) on the sheet surface.
• This (disadvantageous) effect is particularly evident when using higher cooling performance on thin and wide sheets.
• the critical product of a system is given by a sheet with the smallest thickness at maximum width and at the same time high cooling intensity.
• the intensity of the cooling is defined by a high temperature difference between the start and cooling stop temperature with a short cooling time.
• pinch rollers are supposed to hinder this effect of the deformation.
• the influence of this form of compensation is limited.
• the arrangement according to the invention of the Straightening machine before cooling causes plastic deformation and reduces incoming deformations and stresses immediately before cooling.
• the deformations when entering the cooling can be combated particularly effectively by regulating the tensile stress by switching the speed to the next, last, load-bearing pinch roller as the metal strip or sheet progresses.
• One embodiment consists in that the squeeze rolls are fixed with a division, a cooling unit being formed between two squeeze rolls depending on the division.
• this division is set to half a length of the resulting natural shape for a strip or sheet with the smallest thickness, maximum width and high cooling intensity.
• the device for controlled straightening and cooling of a wide metal strip running out of a hot strip rolling mill in particular of a steel strip or of a sheet metal, is equipped with vertical double roller pairs and pinch roller pairs following in the direction of strip travel, between each of which a cooling device is arranged.
• a straightening machine is arranged in front of the pinch roller pairs with the cooling units, between which a controlled tensile stress can be generated. This allows tensile stress to be transmitted before cooling, which already reduces the size of the existing deformations. Then an even more precise determination of the tensile stresses takes place within the cooling units.
• the cooling units are each designed for a high and a medium cooling intensity.
• the influence of the cooling can be further increased by providing the cooling unit with finely adjustable cooling elements in the outlet of the metal strip.
• the cooling can also be developed in such a way that the cooling unit is designed for a high and / or medium cooling capacity in the sense of a given product range.
• Another improvement of the invention consists in the fact that tensile stresses can also be generated between the last, supporting pinch rollers or the straightening rollers at the end of the metal strip or sheet and the pinch rollers or straightening rollers at the beginning of the metal strip or sheet.
• FFiigg .. 22AA is a perspective view of the steel strip or sheet with
• Fig. 2B is a side view of two spaced apart
• Fig. 4 is a view of an overall system for straightening and cooling.
• the metal in particular the steel strip 1 or the sheet metal is guided for controlled cooling and straightening using pinch rollers 5 arranged behind vertical double rollers 3 and 4 in the strip running direction 2 via a tensile stress 6 acting in the longitudinal direction (strip running direction 2).
• a tensile stress 6 acting in the longitudinal direction (strip running direction 2).
• the metal strip 1 is placed between a pre-straightening machine 7 and a spray cooling 8 under defined tensile stresses 6 by regulating the tension (via the rotary drive motors for straightening rollers) and within the spray cooling 8 the metal strip 1 is cooled between successive pinch roller pairs 5a and additionally the Tension 6 checked.
• the spray cooling 8 consists of cooling units 9 each arranged between two pairs of squeezing rollers 5a (FIG. 1).
• the tension 6 is controlled via a corresponding torque 11 by a feedback control 12 with (A) engagement of the pinch rollers 5 (i) to (i + nc). As soon as the belt end 1a passes through (B) engagement of the pinch rollers 5 (i + 1) to (i + nc + 1), the corresponding tension 6 is transmitted to the belt end 1a and only the comparison speed is measured outside the belt end 1a without using the feedback control 12. Both for the end of the strip 1a and for the beginning of the strip 1b, the tension 6 is regulated by switching the speed to the next, last, carrying pinch roller 5 with the passage of the metal strip 1 (see FIG. 1).
• the squeeze rollers 5 are arranged with a certain division 13, the cooling unit 9 being formed between two squeeze rollers 5 depending on the division 13.
• the division 13 can be based on a half length 14 of the resulting wavelength 15 for a metal strip 1 with the smallest thickness, maximum width and high cooling intensity.
• the typical wavelength 15 is set in the steel strip 11 (FIG. 2A).
• the cooling units 9 are each designed for a high or a medium cooling intensity (FIG. 2B), the division 13 corresponding to half the wavelength 15 (cf. FIG. 2B).
• the waveform 16 is made clear in FIGS. 2A and 2B by dotted lines 17. 3 shows the cooling effect of the different types of cooling units 9.
• the solid line represents the temperature profile in the strip or sheet center 20 and the dashed line represents the surface temperature 21.
• Spray sections 8a are used in sections (1).
• Cooling units 9 consisting of U-tube units 22 are provided in the outlet 18 of the steel strip 1.
• the temperature ⁇ T surface is still reached in the zone of the spray cooling units 8a.
• the required cooling-stop temperature is achieved in small steps by the U-tube units 22. A formation of martensite through surface supercooling is prevented above the temperature T-martensite.
• FIG. 4 an overall system is shown, in which the spray cooling 8 with the pinch roller pairs 5a and the cooling units 9 and behind them a laminar cooling device 25 follow in the belt running direction 2 following the pre-straightening machine 7.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Thermal Sciences (AREA)
• Crystallography & Structural Chemistry (AREA)
• Mechanical Engineering (AREA)
• Physics & Mathematics (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Heat Treatment Of Strip Materials And Filament Materials (AREA)
• Metal Rolling (AREA)
• Control Of Heat Treatment Processes (AREA)
• Straightening Metal Sheet-Like Bodies (AREA)
• Investigating Or Analyzing Materials Using Thermal Means (AREA)
• Grinding Of Cylindrical And Plane Surfaces (AREA)

Priority Applications (9)

Applications Claiming Priority (2)

Related Child Applications (1)

Publications (1)

Family

ID=7710240

Family Applications (1)

Country Status (13)

Cited By (1)

Families Citing this family (19)

Citations (4)

Family Cites Families (8)

• 2001
  • 2001-12-20 DE DE10163070A patent/DE10163070A1/de not_active Withdrawn
• 2002
  • 2002-11-21 BR BR0214598-7A patent/BR0214598A/pt not_active IP Right Cessation
  • 2002-11-21 WO PCT/EP2002/013035 patent/WO2003054236A1/de not_active Ceased
  • 2002-11-21 ES ES02785402T patent/ES2261757T3/es not_active Expired - Lifetime
  • 2002-11-21 RU RU2004122098/02A patent/RU2307718C2/ru active
  • 2002-11-21 DE DE50207037T patent/DE50207037D1/de not_active Expired - Lifetime
  • 2002-11-21 AU AU2002350708A patent/AU2002350708A1/en not_active Abandoned
  • 2002-11-21 AT AT02785402T patent/ATE328123T1/de active
  • 2002-11-21 CA CA2469073A patent/CA2469073C/en not_active Expired - Fee Related
  • 2002-11-21 US US10/498,652 patent/US20050016643A1/en not_active Abandoned
  • 2002-11-21 UA UA20040705923A patent/UA77241C2/uk unknown
  • 2002-11-21 CN CNB028257057A patent/CN100402672C/zh not_active Expired - Lifetime
  • 2002-11-21 EP EP02785402A patent/EP1456421B1/de not_active Expired - Lifetime
  • 2002-11-21 JP JP2003554935A patent/JP4440643B2/ja not_active Expired - Lifetime
• 2011
  • 2011-10-11 US US13/270,842 patent/US20120024435A1/en not_active Abandoned

Patent Citations (4)

Also Published As

Similar Documents

Legal Events