Patent ID: 6280542
Filing Date: 2001-08-28
Classification: B21B,C21D

Abstract:
Method for the manufacture of a steel strip, wherein molten steel is cast in a continuous casting machine (5) into a slab and, while making use of the casting heat, is conveyed through a furnace apparatus (7), is roughed in a roughing apparatus (10), and finish-rolled in a finishing apparatus (14) into a steel strip of a desired finished thickness, the method comprising, in an endless or semi-endless process;a manufacturing step selected from the group consisting of a and b, wherein a and b respectively comprise the following:a. manufacturing a ferritically rolled steel strip, wherein the slab is rolled in the roughing apparatus (10) in the austenitic range and after the rolling in the austenitic range is cooled to a temperature such that the steel has essentially a ferritic structure, wherein the strip, the slab or a part of the slab is then rolled in the finishing apparatus (14) at speeds essentially corresponding to the entry speed into the finishing apparatus (14), wherein a subsequent thickness reduction in at least one stand of the finishing apparatus (14) occurs during rolling in the ferritic range, wherein there is no material connection between the steel in the continuous casting machine and the steel rolled in the finishing apparatus, and wherein the strip, the slab or a part of the slab is fed from the roughing apparatus to the finishing apparatus without intermediate storage,b. manufacturing an austenitically rolled steel strip, wherein the strip leaving the roughing apparatus (10) is heated to or held at a temperature in the austenitic range and is rolled in the finishing apparatus essentially in the austenitic range to the finished thickness and, following that rolling, is cooled down to a temperature in the ferritic range, wherein there is no material connection between the steel in the continuous casting machine and the steel being rolled in the finishing apparatus, and wherein the strip, the slab or a part of the slab is fed from the roughing apparatus to the finishing apparatus without intermediate storage;cutting the ferritically or austenitically rolled strip, after reaching the desired finished thickness, to portions of the desired length; andsubsequently coiling the cut portions.