SU1600872A1 - Method of rolling sheet steel and set of single-stand working rolls for effecting same - Google Patents

Abstract

The invention relates to rolling production and can be used on sheet rolling mills. The purpose of the invention is to improve the quality of the metal by eliminating the asymmetry of the texture and improving the mechanical properties. According to the method of rolling sheet steel, when metal is deformed in several passes in tapered rolls with opposite direction of taper, in adjacent passages the direction of taper of rolls relative to the roll is reversed. A set of work rolls contains three conical rolls, the axes of which are located in one plane and parallel. The tapers of the mating rolls are oppositely directed. The invention eliminates the texture asymmetry both in width and in sheet thickness. 2 sec. f-ly. 2 Il.

Description

The invention relates to the field of rolling production and can be used on sheet rolling mills.

The aim of the invention is to improve the quality of the metal by eliminating the asymmetry of the texture and improving the mechanical properties.

Figure 1 shows the scheme of rolling sheets in adjacent passages in a set of work rolls single-mill; Fig. 2 shows a rolling scheme for a two-stand mill.

The method of rolling sheet steel involves the deformation of a metal in several passes in tapered work rolls with opposing taper. When rolling in adjacent aisles, the direction of the taper of the rolls is reversed with respect to the roll.

A set of work rolls single-mill (figure 1) contains two tapered rolls 1 and 2. with opposite taper. The kit is additionally equipped with a third tapered roller 3, the taper of which is opposite to the taper of the roll 2 associated with it.

are lying in the same plane and parallel;

 Pro rolling in tapered rollers creates asymmetrical deformation conditions as per height; so on shi-. Rine stripes. This leads to the fact that in areas with a higher degree of deformation, a pure slip occurs, gliding and bending of planes are skins, and with a smaller degree of deformation only a pure slip. The difference in the reduction of x- will lead to the fact that the crystallites in different parts of the band take on a different / crystallographic orientation with respect to external deforming forces. In addition, a difference is observed in the degree of grain elongation in the rolling direction, as well as in the grain diameter. The greater the difference in the structure, the higher the anisotropy of properties, which is usually undesirable for sheet products. The more complex the texture, the greater the difference in mechanical properties. Therefore, the use of a reduction scheme with i alternating taper directions of the rolls in each subsequent pass will reduce the effect of the asymmetry of the rolling process on the anisotropy of the strip properties.

Example 1. The rolling method is implemented on a single-stand mill with a set of work rolls containing three tapered rolls. The direction of the taper of the mating rolls is opposite to each other (Fig. 1). Rolling in adjacent gaps is carried out between pairs of rolls with opposite to the taper in different levels. In the next i-th pass, rolling is carried out in the lower horizon between rolls 1 and 2, and roll 3 serves as a support for the middle roll 2. In the next (1 + 1) pass, the number of equally-oriented crystallites is equalized by width: the strip, their elongation, diameter, and consequently, the structure due to rolling in the upper horizon between the rollers 2 and 3, while roller 1 serves as a support for the middle

roll 2.

PRI mme R 2. The rolling method is implemented in a two-stand sheet mill 1700 (FIG. 2). In the last glue II, tapered rolls with counter threads are installed to adjust the thickness and flatness of the rolled strips.

five

five

0

0

directional taper o6 3 ° 15. In the penultimate stand I, conic currencies with conicity are also set to o6 3 l5. The direction of the taper, respectively, of the proposed upper and lower rolls of this stand is opposite to the taper of the rolls of the last stand. Temperature-deformation: the rolling conditions of the rolling conditions correspond to those accepted at this mill.

The roll is rolled to a thickness of 3.5 mm in the tapered rolls of stand I, which, at 15 and a width of 1000 mm, provides a degree of mismatch, 83 on the edges of the strip. At the same time, on the right side of the rolling edge of the strip, the diameter of the upper roll is smaller than the diameter of the lower one, and on the side of the left edge, the diameter of the lower roll is smaller than the top.

Asymmetrical rolling conditions lead to different crystallographic orientations of the crystallites from the upper and lower rolls and along the width of the strip, their different elongation in the rolling direction, and different diameters.

When rolling in the conic rolls of stand II “and the final thickness of 2.5 mm, the mismatch of speeds is reversed than in stand I: on the side of the right edge. The strip diameter of the upper roll is larger than the diameter of the lower roll, and on the right edge, the diameter of the lower roll is larger diameter of the top. At the same time, changing the direction of the taper of the rolls in stand II reduces the effect of the asymmetry of the rolling process on the anisotropy of the properties of the strip by equalizing the number of equally-oriented crystallites across the width and thickness of the strip, their elongation and diameter.

The application of the invention allows to improve the quality of rolled sheets by eliminating the asymmetry of the texture of the deformed metal, both in width and in the thickness of the sheet.

Claims (1)

Invention Formula 1, A method of rolling sheet steel, including the deformation of a metal in a few number of passes in tapered work rolls with opposing taper, different in that 4TOj in order to improve the quality of by eliminating texture asymmetry and improving mechanical properties, in adjacent passages, the taper of the rolls is reversed in relation to the roll 2, A set of work rolls of a single-stand mill for rolling sheet steel, including two conical 872 L a roll with an oppositely directed taper, characterized in that it is provided with a third conical roll, the taper of which is opposite to the taper of the associated roll, and the axes of all the rolls are in the same plane and parallel to each other. but  .r- 2. Stand g / “YY Scream l Fi, g 2