Method for producing a metal strip
The invention relates to a method for producing a metal strip from a cast by rolling in which method the technique of a profiled rolling in combination with a strip rolling is used. The material for the metal strip is first cast by using a casting technique to produce a cast profile having the center part thicker than the lateral parts and the cast profile is in an essentially continuous manner conducted into a rolling mill where during the at least two-staged profiled rolling the cast profile is divided into two symmetrical segments and maintained as two equal segments. These segments are spread into the lateral regions of the material to be rolled into a flattened profile which is as an object for at least one-staged strip rolling so that the spread ratios between the center part dimension of the cast profile and the width of the strip of greater than 2.8:1 are achieved.
1. Method for producing a metal strip from a cast by rolling, in which method the technique of a profiled rolling in combination with strip wiling is used, the method comprising:
casting material for the metal strip to produce a cast profile having a center part that is thicker than lateral parts thereof;
conveying the cast profile in an essentially continuous manner into a rolling mill, during an at least two-staged profiled rolling;
providing rolling surfaces of the working rolls that include, in cross-section, at least a center portion that is continuously curved;
dividing the cast profile into two symmetrical and equal segments; and
spreading the two equal segments into lateral regions useful for one-staged strip rolling, so that a spread ratio between the width of the strip and a center part dimension of the cast profile is greater than 2.8:1.
2. Method according to claim 1 , further comprising casting in an essentially vertical direction.
3. Method according to claim 2 , further comprising feeding rod material to be rolled in each rolling stage into a gap between two working rolls.
4. Method according to claim 1 , further comprising casting in an essentially horizontal direction.
5. Method according to claim 4 , further comprising feeding rod material to be rolled in each rolling stage into a gap between two working rolls.
6. Method according to claim 1 , further comprising casting in a slant position.
7. Method according to claim 1 , further comprising feeding rod material to be rolled, in each rolling stage, into a gap between two working rolls.
8. Method according to claim 1 , further comprising carrying out the wiling stages for the profiled rolling and for the strip rolling in separate rolling devices.
9. Method according to claim 1 , further comprising using working rolls in which a rolling surface of a first working roll of each rolling stage is substantially identical to a rolling surface of a second working roll in the same rolling stage.
10. Method according to claim 1 , further comprising providing using working rolls in which the shortest distance between rolling surfaces of each pair of working rolls in each profiled rolling stage are substantially equal.
11. Method according to claim 1 , further comprising increasing during profiled rolling, stage by stage, a mechanical contact area between the material being rolled and rolling surfaces of the working rolls.
12. Method according to claim 1 , further comprising providing rolling surfaces of the working rolls that are, in cross-section at their center parts, convex curved.