Method for the controlled pre-rolling of thin slabs leaving a continuous

Abstract

Method for the controlled pre-rolling of thin slabs (20) leaving a continuous casting plant, whereby the pre-rolling is carried out with a plurality of pairs of rolls (14-16), a first pre-rolling assembly (10) being positioned immediately downstream of foot rolls (12) of a mold (11), at least one displaceable roll (16) being included in the pairs of rolls (14-16), the pairs of rolls (14-16) being associated with pressure transducer (18) and hydraulic capsule (17), position transducer (24) being included. The pressure transducer (18) and position transducer (24) can be associated with a data processing unit (21), at least the first of the pairs of rolls (14-16) processing a slab (20) which has just emerged from the mold (11) with a thin solidified skin. The method achieves a pre-rolling with a reduction of the thickness of the slab (20) leaving the last pair of pre-rolling rolls (14-16) by at least 10% so as to eliminate the liquid core and to bring into contact the zones in a two-phase condition in order that the central solidification structure be refined and the central separation be minimized. Device suitable to carry out the controlled pre-rolling of thin slabs according to the above method, which comprises an element (25a) to monitor the temperature of the liquid bath in a tundish, an element (25b) to monitor the temperature of a slab (20), an element (26) to monitor the speed of the slab (20) and an element (28) to monitor the inclusion of a liquid cone.