SU1720785A1 - Sheet ingot - Google Patents

Abstract

The invention relates to sheet-rolling production and can be used in the production of ingots for rolling thick sheets and slabs. The purpose of the invention is to reduce metal losses with trimming. Sheet ingot contains the body, profitable and bottom parts, and the latter has wide and narrow edges. Each wide face in cross section is bounded by a symmetric convex curve with a vertex located on an axis passing through wide faces. 3 ill., 1 tab.

Description

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The invention relates to sheet rolling production and may be used in the design of ingots for rolling thick sheets and plates.

A tetrahedral ingot is known, having a profitable part and a body bounded by conical edges. The Kumpelnna (bottom) part of the ingot is bounded by straight edges corresponding to the facets of the ingot body.

The use of a cumpel in sheet ingots leads to an increased metal loss with side cutting during rolling due to the considerable razoschirinnost sheet products. Kumpel, not crimped in the first passes at the stage of dividing the width and being a non-deformable outer zone, hinders the extraction of the bottom part of the ingot body. In the final

this ultimately determines additional losses with side trimming.

Famous ingot containing the body, profitable and bottom parts in the form of truncated pyramids, in which the faces of the bottom parts are made wavy with a wavelength equal to the height of the face and the wave height equal to 0.03-0.2 of its length.

However, the bottom part in the ingot does not eliminate the disadvantages indicated earlier. Metal losses during rolling of sheet ingots with this variant of the bottom part are significant.

The purpose of the invention is to reduce trimming when rolling thick plates of steel by reducing the raras width.

In order to reduce rolling losses with face trimming in sheet ingots, the dimensions of the bottom part are chosen as low as possible. As a result, in the first

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The gaps during the breakdown of the width of the vial are not crimped and, being a non-deformable outer zone, they restrain the stretching of the narrowest bottom section of the bar. Earlier deformation of the cumpel without increasing its mass is provided by convex profiling of its wide faces. The thickness in the center is increased and gradually decreases towards the edges of the cumper. The effect of reducing the side trimmings with razrashirinnost is achieved without increasing losses with the bottom trimmings.

FIG. 1 shows a sheet ingot, a general view; in fig. 2 is a diagram of the transition to the proposed design for an ingot being poured in one jet; in fig. 3 is the same for ingots poured in two streams.

Sheet ingot contains body 1, profitable 2 and bottom 3 parts. The wide face 4 of the bottom part 3 in the cross section is bounded by a convex curve with the top located on the axis 5 passing through the wide faces of the ingot. The thickness of the cubicle in the center is maximum bc and decreases to the lateral edges.

During the transition to a convex wide face, it is necessary to ensure the condition of damping the energy of the incident metal during casting. The kumpel must overlap the supply jet (dashed lines in Figures 2 and 3). In order to achieve other goals in the proposed construction of the bottom part, the cusp of the convexity can be cut off, a waviness is additionally superimposed on the profile. However, it is necessary to take into account that with a decrease in the thickness of the kyumpel the positive effect decreases.

The proposed ingot was tested under laboratory conditions.

Lead specimens of 44 x 100 x 120 mm were made, on the ends of which wedge-shaped protrusions simulated a cupel with dimensions of 50 x 25 and 75 x 30 mm in cross section adjacent to the ingot body. The control samples are wide

the sides of the cumpel were straight, the other two samples had a convex wide face. The thickness of the bottom part in the center of the tube is 30 and 38 mm, respectively. The convexity of the wide face is described by a parabola of the form ux (as one of the variants of a specific design). To eliminate the influence of the mass of the cubicle on the control and test samples (in pairs), the bottom parts have the same cross section. For this, in the first case the parabola has the form of 0.012 x, and in the second, 0.0085x2. The coefficients are obtained from the condition of equality of areas under the straight line and curve

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G (-Kb2).

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During the rolling process, the width of the rolls in the center and in the bottom section is measured. For the parameter of width, the ratio of the width of the roll of the roll in the center and from edge to width in the center is taken.

The experimental data after rolling with a stretch of 1.25 are presented in the table.

It follows from the table that when going to the bottom part with a convex wide edge (options 2.4), the razroshirinnost on peal decreases by 1.0-1.5%.

In addition, when the ingot is rolled with the proposed bottom structure, the metal flows from the ingot body to the bottom edge area are reduced.

The use of an ingot of the proposed construction allows to reduce the cut during rolling by 0.5-0.5

Claims (1)

Claims of Invention A sheet ingot containing a body, a profitable and a bottom part, the latter having wide and narrow edges, is characterized in that, in order to reduce metal loss with a cut, each wide face of the bottom part of the ingot is bounded by a convex surface that is symmetrical with respect to it axis. / / five 1 FIG. 2  five Fi.Z