SU959854A1 - Rolled stock production method - Google Patents

Description

(54) METHOD OF MANUFACTURING ROLLS

one

The invention relates to metallurgy, in particular, to the production of sheet metal from alloyed steels and alloys from continuously cast slabs.

A known method for improving the quality of metal products is that the rectangular slab is divided longitudinally into two parts along the axis of symmetry, then, in the exit zone of the untitled zone to the surface, a Q hole is formed, deforming the billet in the rolls of the 1C) Rolling Mill, after bringing the edges of the hollow together to contact, turn the workpiece through 90 ° and roll it 1.15

However, this method does not allow the full:. to remove the bone segregation zone with a bone, the edges of the depression are oxidized, therefore welding of the metal and closure of the quational zone 20 do not occur. In this regard, during further processing, by pressure or operation, separation occurs in the segregation zone of chemical elements and non-metallic inclusions segregation, which; is a rejection trait.

The closest to the technical essence of the present invention is a method for the production of rolled products, including the separation of a continuous slab on the baseline axis in the plane of axial segregation. On the larger axis of symmetry of the cross section i into blanks and the subsequent rolling of the obtained blanks 2.

A disadvantage of the known method is the considerable loss of metal by cutting the slab, and simultaneously with the waste of the metal of the axial zone there is a waste of metal without microdefects of shrinkage origin along the edges wide. ; faces sla ba. When the aspect ratio of slab is 2-10, metal loss without segregation microdefects results in 5–25% of the total loss, which in turn l: reaches 5% of the slab weight.

Claims (2)

The purpose of the invention is to reduce metal losses during separation by reducing the separation zone. 39 The goal is achieved by the fact that in the method of rolling production, including the separation of a continuously cast slab along a longitudinal axis in the plane of axial segregation along the major symmetry axis of the cross section into blanks and the subsequent rolling of the obtained blanks, before separating the edge of one of the wide edges of the slab The 0.4 – O, 6 thicknesses of the slab are formed equal to 0.35–0.5 of the thick slab in the middle of its wide faces. Moreover, a reduction in the thickness of the edges of the wide faces of the slab is done by squeezing them into rolls with a degree of deformation of at least 50%. FIG. Figures 1 and 2 schematically show a cross section, before splitting it. On a continuous casting machine, production of slab 1 (Fig. 1), its macrostructure is characterized by a pronounced segregation zone 2 in the form of a cord. The length of the liquation zone along the wide face depends on the ratio of the faces of the slab and is equal to 70-90% of the length of the wide face of the slab. After casting slab 15) Oiz Ezod t compression of the ends of one of the wide faces in the rolls of the rolling mill (Fig. 2). Deformation is carried out only on the slab areas along the edges of one of the wide faces at a distance O, 40, 6 of the slab thickness from the narrow face. The magnitude of the degree of deformation is at least 50%, which makes it possible to obtain a slab thickness at its ends equal to 0.35-O, 5 slab thickness in the middle of its wide faces. A decrease in the thickness of the ends of the wide faces of the slab allows one to exclude the loss of the metatsha of these sites when the slab is divided. The extent of the section of the slab with a smaller thickness along is determined by the length of the segregation zone. Experiments have shown that for slabs with an aspect ratio of 2-10, the length of the elimination zone is 0.7-0.9 the length of the wide face of the slab. The formation of areas with a smaller thickness of 0.40, 6 times the thickness of the slab allows the segregation zone to be brought to the metal surface. If these areas with a length of less than 0.4 slab are formed, then when the slab is separated, a part of the pure metal is removed along with the segregation. Otherwise, when the thinner areas have a length of more than 0.6 slab thickness, the metal contaminated with liquids is displaced along the vertical axis and therefore, when divided, the segregation zone is not removed, sac and subsequent rolling. If the thickness of the extreme parts of the slab is more than 0.50 of the slab thickness in the middle of the wide faces, then when the slab is divided into slab, a part of the healthy metal passes into frenzy. If the thickness of the extreme parts of the slab to form less than 0.35 of the slab thickness, then the cost of this operation increases, which increases the cost of 1 mill and makes it more difficult to produce rolled products from separated billets due to the speed of the latter. Example. SL b Sh1fina 1200 mm and a thickness of 250 mm cast on the machine. continuous casting of steel 09Г2 after heating to a temperature is fed to the line of the rolling mill. Here, in one pass, a compression of the edges of one of the wide faces of the slab is formed, forming a stepped profile. Thickness sl ba; at the ends of its wide edges, it is 120 mm (deformation degree 52%) or 0.48 of the thickness of the base in the middle of its wide edges. The length of the slabs with a thickness of 12 mm is 125 mm (0.5 thickness of the slab). Next, the roll is subjected to longitudinal cutting flame cutter on the plane of axial segregation. The resulting blanks are cleaned with an needle-milling machine along the separation plane. The result is a billet size in cross section of 950 x 120 mm and 1250 120 mm with an isotropic structure without axial segregation, which are used for the production of sheets of appropriate purpose. The economic efficiency of the proposed method is determined by reducing the loss of metal in carbon monoxide, slag and scale 1FI longitudinal separation of slab. The annual economic effect is 122.5 thousand rubles. , Invention 1. Method of rolling production, including separation of continuously cast slab along the longitudinal axis in the plane of axial segregation along the major axis of symmetry of the cross section into blanks and subsequent rolling of the obtained blanks, characterized in that in order to reduce metal losses during separation by reducing the zone before separation, the edges of one of the wide faces of the slab at a distance of 595; O, 4-O, 6 thicknesses of the slab are formed equal to 0.35-O; 5 thicknesses of the slab in the middle of its wide faces. 2. The method according to p. 1, that is, so that the reduction of the thickness of one face of the right side of the slab is done by squeezing them into rolls with a degree of not less than 50%. ; at 4 Sources of information taken into account in the examination I. Patent 4 of Fashio No. 697670, cl. 2, gr. 8, (Shublik. 1931. 2. Copyright svdedetstvo USSR M 598043, class B 21 B 1/38, published. 1978.