Classifications

• • 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
  • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
  • B21C47/00—Winding-up, coiling or winding-off metal wire, metal band or other flexible metal material characterised by features relevant to metal processing only
  • B21C47/02—Winding-up or coiling
• • 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

Definitions

• the invention is directed to a process for the production of hot-rolled steel strip from continuously cast precursor strip in at least two deformation stages, each deformation stage having one or more roll stands, wherein initial rolling is carried out in the first deformation stage at the output speed at which the precursor strip exits from the continuous casting plant and the intermediate strip thus produced is coiled prior to the second deformation stage at the output speed at which it exits from the first deformation stage, wherein the coil is uncoiled after reaching the coil weight and is supplied to the second deformation stage for finish rolling at the initial roll pass speed and is then coiled in the desired finished coil sizes.
• a process of the type mentioned above is described, for example, in the German Patent 38 40 812 C2 and has become known in technical literature as the ISP process.
• An essential characteristic of this process is the two-stage rolling process in which the first deformation stage is carried out directly following the casting machine at casting speed and the second deformation stage is carried out at an appreciably higher rolling speed.
• These two rolling process stages are linked by an intermediate coiling system in the form of a coiling furnace in which the continuously cast slab is coiled after being rolled down, wherein the weight of the coil corresponds to the desired finished coil weight.
• the strand which is initially generated in an endless manner is therefore divided following the first deformation stage when the coil weight reached in the coiling furnace is equal to the weight of the finished coil after rolling down in the second deformation stage.
• precursor strips are produced by the continuous casting process and wound into coils whose weight corresponds to the weight of the finished strip coil.
• the precursor strip is severed after reaching the coil weight in the intermediate coiling station and is accordingly disconnected from the casting plant so that the strip can be uncoiled in the finishing train at high speed.
• rolling speeds are limited so that considerable problems occur specifically when rolling thin hot strip in the order of magnitude of less than 1.5 mm. Conventional plants are therefore incapable of producing thin hot strip in large quantities.
• this object is met in that in the first deformation stage at least 40 tons of a casting sequence of the continuous casting plant is rolled out in endless manner to form intermediate strip and is coiled to form an intermediate coil without severing, and in that after more or less endless finish rolling the intermediate strip of this intermediate coil is severed according to the desired coil weights and coiled as finished strip only following the second deformation stage.
• precursor material is produced by an endless rolling process for finishing in the finishing train.
• the precursor material with the intended object of endless rolling is not cut behind the deformation group, but rather is wound, without cutting, into an intermediate coil comprising a plurality of finished coils.
• an intermediate coil comprising a plurality of finished coils.
• a plurality of coil lengths are then finished in an endless rolling process in the finishing train.
• the size of the intermediate coil is limited only by the mechanical configuration of the coiling unit and the rolling time in which the finishing train can be operated without changing rolls. With suitable coiling devices, it is entirely possible to carry out endless rolling of whole casting sequences of a continuous casting plant, but at least substantially greater tonnages can be rolled out than would be possible in plants according to the prior art.
• the process steps according to the invention appreciably increase the buffer capacity of the intermediate coiling system. With a coiling capacity of approximately 100 tons, for example, the buffer capacity would increase to 60 minutes per intermediate coil. Due to the higher final rolling speeds which are made possible by a procedure of the type mentioned above, hot strip with thicknesses of less than 1.2 mm can easily be produced in an endless manner.
• the yield of the plant is improved because the typical rough-rolled end or rolling tongue which must be removed before further processing develops only for the start of the first coil and the end of the last coil behind the finishing train.
• the quality of the rolling stock can be improved because the non-steady state of the initial pass impact or shock takes place only once in the first coil.
• the winding of the intermediate strip to form an intermediate coil can be carried out with or without mandrel. Further, according to another feature of the invention, the metallurgical characteristics within an intermediate coil length can be changed by changing the temperature control prior to winding the intermediate coil and/or prior to the second deformation stage and by flexible speed control.
• the geometrical characteristics of the finished coil produced from an intermediate coil are changed by suitable adjustment of the rolling parameters during the deformation of the intermediate strip within the second deformation stage.
• the advantages of the present process consist in the possibility of endless rolling without welding of precursor strip, endless rolling with homogeneous precursor strip characteristics with respect to temperature and geometry, increased production in the plant through higher possible rolling speeds which are no longer limited by the threading-in processes in the coiler, and in the creation of greater buffer capacity between the casting strand and the finishing train.
• the process can be applied in single-strand or two-strand plants, wherein the coiling principle for the precursor strip can be carried out with a mandrel in coiling furnaces or without a mandrel in coil boxes, as they are called.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Metal Rolling (AREA)
• Heat Treatment Of Strip Materials And Filament Materials (AREA)
• Superconductors And Manufacturing Methods Therefor (AREA)
• Heat Treatment Of Steel (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=7793281

Family Applications (1)

Country Status (10)

Citations (4)

Family Cites Families (7)

• 1996
  • 1996-04-23 DE DE19617856A patent/DE19617856C1/de not_active Expired - Fee Related
• 1997
  • 1997-03-20 ZA ZA9702449A patent/ZA972449B/xx unknown
  • 1997-04-15 RU RU98120908/02A patent/RU2170640C2/ru not_active IP Right Cessation
  • 1997-04-15 EP EP97921621A patent/EP0904165B1/de not_active Expired - Lifetime
  • 1997-04-15 AT AT97921621T patent/ATE213974T1/de active
  • 1997-04-15 DE DE59706562T patent/DE59706562D1/de not_active Expired - Lifetime
  • 1997-04-15 CN CN97194060A patent/CN1081097C/zh not_active Expired - Fee Related
  • 1997-04-15 US US09/171,735 patent/US20010007267A1/en not_active Abandoned
  • 1997-04-15 WO PCT/DE1997/000787 patent/WO1997039842A1/de not_active Application Discontinuation
  • 1997-04-15 JP JP53759197A patent/JP4056086B2/ja not_active Expired - Fee Related
  • 1997-04-21 ID IDP971307A patent/ID19561A/id unknown

Patent Citations (4)

Also Published As

Similar Documents

Legal Events