A Creep Bending Creep Straightening Method for Straight Arc Continuous Casting Machine

Abstract

The invention discloses a creep bending and creep straightening method for a vertical-arc continuous casting machine. The creep bending and creep straightening method comprises the steps that the yield strength sigma s of a continuous casting billet material within the temperature range from a bending segment to a straightening segment is determined, the constant stress sigma of the continuous casting billet material for a high-temperature creep tensile test is selected, and sigma is smaller than sigma s; the minimum creep strain rate of the continuous casting billet material at a certain temperature and under the condition of being lower than the yield stress sigma s is determined; according to the thickness D and allowable strain of a continuous casting billet and the casting machine height, metallurgical length and drawing speed process parameters of the machine type of the vertical-arc continuous casting machine, the curvature change rate of the bending segment is higher than that of the straightening segment, the basic arc segment arc length is reduced, and the creep time of the continuous casting billet is shortened, so that the continuous casting billet has enough time to carry out creep deformation in the bending and straightening process; and the proper machine type curve is selected, the stress rate of the continuous casting billet on the bending segment and the straightening segment is lower than the minimum creep strain rate determined in the test, creep deformation occurs at the state lower than the yield stress, and finally the creep bending and creep straightening of the continuous casting billet are achieved.

Description

technical field [0001] The invention belongs to the field of continuous steel casting, in particular to a creep bending creep straightening method of a straight arc continuous casting machine. Background technique [0002] Bending and straightening technology of continuous casting slab is a key technology in continuous casting of iron and steel. The bending and straightening process of the straight arc continuous casting machine refers to the process that the continuous casting slab bends from vertical under the action of external torque, and then the continuous casting slab with a certain radius of curvature becomes horizontal through the straightening torque. With the development of today's high-efficiency continuous casting technology, the bending and straightening methods of continuous casting slabs have gradually developed from single-point bending and single-point straightening to multi-point bending, multi-point straightening, progressive bending, progressive straight...

AI Technical Summary

Problems solved by technology

[0005] The invention provides a creep bending creep straightening method for a straight arc continuous casting machine. The technical problem to be solved is: according to the high-temperature creep characteristics of the continuous casting billet material, the continuous casting billet deforms quickly in the bending section, and the continuous casting billet deforms quickly in the bending section. The straightening section deforms slowly, reasonably distributes and prolongs the arc length of the bending section and the straightening section, and shortens the arc length of the basic arc section, so that the stress of the billet during bending and straightening deformation is less than the yield stress, and no plastic deformation occurs. Relying on creep deformation for creep bending and creep straightening can avoid the generation of cracks and improve the quality of cast slabs

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