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
• • 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
  • C21D8/0226—Hot 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
  • C21D8/021—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips involving a particular fabrication or treatment of ingot or slab
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T29/00—Metal working
  • Y10T29/49—Method of mechanical manufacture
  • Y10T29/4998—Combined manufacture including applying or shaping of fluent material
  • Y10T29/49988—Metal casting
  • Y10T29/49989—Followed by cutting or removing material
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T29/00—Metal working
  • Y10T29/49—Method of mechanical manufacture
  • Y10T29/4998—Combined manufacture including applying or shaping of fluent material
  • Y10T29/49988—Metal casting
  • Y10T29/49991—Combined with rolling

Definitions

• ABSTRACT 5/1971 Stone et al ..l64/76 X Primary Examiner-J. Spencer Overholser Assistant Examiner-John E. Roethel Attorney-Brumbaugh, Graves, Donohue & Raymond 5 7] ABSTRACT
• the invention relates to a method for the production of plates from continuously cast slabs. Immediately after the continuously cast bar has solidified and as soon as its marginal zone has reached a mean temperature of 800 to 1000C while the core zone is still of higher temperature, a continuously cast bar is shaped in a preliminary One-step shaping process in which primarily the core zone is shaped.
• the slabs After shear ing to length, the slabs are cooled, re-heated to rolling temperature and shaped in a multi-step rolling process proper wherein essentially the marginal zones of the slabs are subjected to shaping so that finally a uniform degree of shaping is achieved over the total cross section of the slabs.
• the invention relates to a method for the production of plates from continuously cast slabs.
• rolled products show satisfactory technological characteristics'only when the cast product receives at least a fourfold, preferably at least a sixfold shaping so that the as-cast structure is destroyed and one may be certain that thematerial is transformed not only in the marginal zones but also in the core of the rolled product to obtain a uniform as-rolled structure.
• a total of a sixfold shaping may include only a threefold shaping in the core of the rolled product.
• the degree of shaping must be as high as possible because the marginal zones which are turned towards the rolls, are always shaped to a greater extent than the core zone.
• the invention is aimed at avoiding these drawbacks and difficulties and, in a method for the production of plates from continuously cast slabs, wherein these slabs are heated to rolling temperature and shaped in several steps, resides in that the cast bar prior to being shorn to length, immediately after its solidification in the continuous casting process, is shaped in one step as soon as its marginal zone has reached a mean temperature of 800 to 1000C while the core zone is still of a higher temperature, preferably of a temperature that is higher by atleast 100C.
• the core zone that is shaped, while the marginal zone remains substantially unshaped. Only later, after shearing to length, cooling, re-heating of the slabs, in the multi-step rolling process proper, the marginal zone is shaped so that finally a uniform degree of shaping is achieved over the total cross section.
• the core zone which amounts to from about one fifth to about one third of the total bar cross section is subjected to a 1.3 to 2.5 fold shaping during the one-step shaping process of the bar and the entire cross section of the continuously cast bar is reduced by 7 to percent.
• the one-step shaping process according to the invention suitably takes place by means of a customary shaping stand arranged after the secondary cooling zone of the continuous casting plant,
• the first shaping is carried out by exploiting the sensible heat of the bar. Owing to the fact that the resistance to shaping. increases with declining temperature and increases greatly at temperatures below about 900C, the core zone of a bar having a high temperature will be shaped to a greater extent than its marginal zones having relatively low temperatures; in other Words, the core zone will be shaped thoroughly while the marginal zones will hardly be shaped at all.
• the surface may be cleaned, if desired, before the slab is introduced into the pusher-type furnace where it is heated to rolling temperature.
• the multi-step second rolling process takes place in known manner on a customary train of rolls at normal rolling temperatures; i.e. the slabs to be rolled are uniformly heated. What has been described in the introduction will happen now in this second rolling process, i.e. the core zone is shaped to a lesser degree than the marginal zones. Seeing, however, that the initial thickness of the continuously cast slab was reduced by the first shaping process in the stand of rolls arranged after the continuous casting plant, the second shaping process further improves the shaped condition of the core zone or center.
• the second rolling process thus serves to equalize the different degree of shaping resulting from the first rolling process.
• An examination of the cross section of the plate shows that shaping has been effected in a highly uniform manner. Plates produced according to this method have a thickness of about 50 to 100 mm and boast improved technological characteristics although shaping has been effected only to a three or fourfold degree.
• Example 1 illustrates the shaping of a bar having an initial cross section of 210 mm which is shaped to a final cross section of 75 mm in two steps, namely in a preliminary shaping process after complete solidification of the bar and in a rolling process after heating the continuously cast slat to rolling temperature.
• the core zone received a 1.75 fold shaping in the first rolling process while the marginal zones received only a 1.08 fold shaping.
• the core zone received a 1.6 fold shaping while the marginal zones received a 2.6 fold shaping.
• the finished plate shows a uniform 2.8 fold shaping throughout its cross section.
• Example 2 illustrates the shaping of a bar whose core zone C was assumed to amount to not more than onefifth one of the entire diameter D.
• the core zone shows a 2.5 fold shaping, while the degree of shaping of the marginal zones is extremely low with 1.05.
• the marginal zones received a 2.35 fold shaping, while the core zone received only a 1.05 fold shaping.
• Example 3 illustrates the shaping of a bar whose core zone C was assumed to amount to not more than about one-fifth of the total diameter D; also, it was assumed that the entire reduction of the cross section achieved in the first rolling process amounts to only 7.5 percent.
• the core zone receives a 1.33 fold shaping in the first rolling process, while the marginal zones receive a l .03 fold shaping only.
• the marginal zones are shaped to a substantially higher degree than the core zone so that finally a plate is obtained showing in total a 2.67 fold shaping of the core zone and a 3.2 fold shaping of the marginal zone which again does not greatly deviate from the average total degree of shaping of 3.08.
• the method according to the invention makes it possible to use continuously cast slabs for the production of thick plates, whereas until now it had been necessary for this purpose to use heavy slabs having a thickness of more than 600 mm.
• a method for the production of plates from continuously cast bars comprising continuously casting a bar subjecting said bar to a one-step shaping operation when the mean temperature of the marginal zone is in the range from about 800 to 1000C, the temperature of the core zone is greater than the temperature of the marginal zone, and the core zone comprises about one-fifth to one-third of the cross section of the bar, shaping said core zone about 1.3 to 2.5 fold by said one-step shaping operation,
• the temperature of the core zone is in the range from about 800 to 1000C and the temperature of the core zone :is greater, reducing the cross section of the bar about 7 percent to 20 percent by said one-step shaping operation, shearing said bar to form individual slabs and allowing said slabs to cool, re-heating said slabs to rolling temperature, and subjecting said slabs to a rolling process to form plates.

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• 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)
• Metal Rolling (AREA)

Applications Claiming Priority (1)

Publications (1)

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ID=3564094

Family Applications (1)

Country Status (12)

Cited By (7)

Families Citing this family (6)

Citations (6)

• 1969
  • 1969-05-09 AT AT444469A patent/AT291898B/de not_active IP Right Cessation
• 1970
  • 1970-04-13 SE SE7004990A patent/SE371944B/xx unknown
  • 1970-04-23 FR FR7014871A patent/FR2046435A5/fr not_active Expired
  • 1970-04-23 DE DE19702019700 patent/DE2019700A1/de active Pending
  • 1970-04-27 ES ES379080A patent/ES379080A1/es not_active Expired
  • 1970-04-27 US US00032459A patent/US3710436A/en not_active Expired - Lifetime
  • 1970-04-30 SU SU1433635A patent/SU401036A3/ru active
  • 1970-05-06 CH CH677870A patent/CH504258A/de not_active IP Right Cessation
  • 1970-05-08 CS CS321570A patent/CS155239B2/cs unknown
  • 1970-05-08 BE BE750119D patent/BE750119A/xx unknown
  • 1970-05-08 GB GB2243170A patent/GB1307562A/en not_active Expired
  • 1970-05-08 CA CA082,248A patent/CA939173A/en not_active Expired

Patent Citations (6)

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