SU1493336A1 - Method of rolling l-beams - Google Patents

Abstract

The invention relates to rolling production and is intended for use in the production of channels on mills with universal stands. The aim of the invention is to improve the quality of rolled metal by preventing the formation of sunsets from excess metal on the inner and outer surfaces of the shelves at their bases - by local re-exposure of these places in the area where the deformation centers of the horizontal and vertical rolls are combined with the subsequent roll-out of the recesses formed behind this section by vertical or horizontal rolls according to the direction of their displacement during rolling relative to each other. The application of the method makes it possible to use the rolling method with vertical rolls displacement relative to horizontal rolls: in the direction of the rolling course — if necessary, increase this broadening or against the rolling course — to reduce it more efficiently without sacrificing the quality of the car. In this case, the magnitudes of local rebounds, ensuring the absence of sunsets at the bases of the shelves, are set to optimal limits depending on the magnitude and direction of the relative displacement of the horizontal and vertical rolls. 9 il.

Description

The invention relates to rolling production and is intended for use in the production of channels on mills with universal stands.

The purpose of the invention is to improve the quality of rolled metal by preventing the formation of sunsets from excess metal at internal and external surfaces at their base.

FIG. 1 shows a shaped tackle; in fig. 2 and 6 are characteristic positions of deformation areas of the shelves and walls in universal gauges with vertical rolls displaced along and against the course of rolling, respectively; pas figs. 3-5 - stages of deformation of a roll in a universal caliber with vertical rollers, shifted

while rolling; in fig. 7-9 - stages of deformation of a roll in a universal caliber with vertical rollers offset against the course of rolling.

The proposed method can be implemented in the process of rolling the shaped tread 1 (Fig. I) in universal gauges, the design of which provides the ability to control the broadening of the shelves by shifting the vertical wafers relative to the horizontal rolls along the hoop or against the rolling stroke.

In the first case (Fig. 2), the mutual location of the deformation areas of the shelves / "and the syngine / st is determined by the grand displacement /" of the boundaries (plane III 111) of the deformation points of the shelves relative to the boundary (plane CO

WITH

with

O5

bone II-ii) deformation zone of the wall during rolling. Obviously, in the adopted metal deformation scheme, the displacement parameter 1t determines the length // of the joint deformation region of the shelves and the wall. The dynamics of the change in the scheme of metal reduction in the universal caliber (Fig. 3-5) is shown on the example of such characteristic stages of deformation along the length of the deformation centers of the shelves and the wall, as the beginning (section vertical plane I - 1) and the end of the deformation points.

The roll is rolled in a universal caliber (Fig. 2-5), formed by a pair of horizontal rolls 2 and 3 and a pair of vertical rolls 4, displaced during rolling. From the moment of the beginning of the deformation of the shelves with annular shoulders 5 of the lateral surfaces of the lower horizontal roll of the shelf at their base, the vertical rolls are recompressed in the direction a (Fig. 3) until the recesses are formed. The process of pereobzhat shelves in these areas is completed with the end of the deformation of the wall, i.e., the rebound is localized by the joint deformation of the shelves and the wall. The formed depressions roll up after this section on the remaining part of the deformation zone of the shelves due to the widening of the metal in the direction a of the horizontal roll. The width of the annular shoulders / g is determined by the magnitude of the displacement I m.

In the second case (Fig. 6), the relative position of the deformation sites of the shelves and the wall is determined by the amount of displacement of the vertical rolls against the rolling stroke. The dynamics of the change in the scheme of metal reduction in the universal caliber (Fig. 7-9) is shown similarly to the variant with the displacement of the vertical rolls in the course of rolling.

The roll is rolled in a universal caliber formed by a pair of horizontal 6 and 7 and a pair of vertical 8 rolls offset against the course of rolling. The annular shoulders 9 of the working surface of the vertical rolls of the shelf at their base are rebound in the direction c (Fig. 7) of the horizontal roll until the recesses are formed. The pereobzhat process at these sites ends with the end of the deformation of the shelves. The formed depressions roll up on the remaining part of the deformation zone of the wall due to the expansion of the metal in the d direction (Fig. 9) of the vertical rolls. The width of the annular shoulders ht is determined mainly by the amount of wall compression

.

It was established experimentally that when rolling channels in universal gauges with shifted vertical rolls, the amount of overcoating should be chosen from the condition of 0.08-0.15 magnitude of displacement.

0

five

0

50

five

five

0

Going beyond the specified range does not ensure the quality of the profile.

Thus, rolling the channels with the ratio of the size of pereobzhati shelves at their base and the magnitude of the displacement, less than 0.08, is accompanied by the appearance of such a defect as an excess of metal in the places where the flange transitions into the walls from the side of the horizontal roll.

ct

Compressing roll when -p- and exceeded LWn

0.15, does not provide high-quality rolling of the formed recesses. The remaining groove-like defects in the form of grooves are practically not rolled out in subsequent passes. In this case, smaller values of the indicated ratios are taken for gaps that are close to fair, large ones - mainly for rough ones.

It was established that the width of the annular shoulders, which determines the degree of localization of the overbinding of the shelves at their base, ensures faultless rolling at, 2-0.35) C - in the case of displacement of the vertical rolls during rolling and (3.5-6.5)) (d , -d, + i) - in case of displacement against the course of rolling. The shape and dimensions of the annular shoulders, made on the lower horizontal roll, must comply with the requirement of no undercut during rolling. In this regard, the limiting sizes of the shoulders (their height) impose restrictions on the maximum amount of displacement.

Thus, if the width of the annular shoulders is less than the established recommended range, the rolling of the recesses is accompanied by the formation of an excess of metal in the form of a slight influx of metal on the shelves at their base. Naturally, this excludes the use of universal calibers in finishing passes. Going beyond the specified limits towards the maximum does not allow for the broadening of the metal at the transitions of the shelf into the wall, the roll-in of the depressions occurs unevenly in width, and grooves are formed at these sites.

The disadvantage of rolling with the displacement of vertical and horizontal rolls is usually that at the final stage of deformation of the roll, beyond the zone of joint deformation of the shelves and the wall at the base of the shelves, there are unworkable zones on their inner (when the vertical rolls are displaced during rolling) or outer ( when the vertical rolls are offset against the rolling course) surfaces. As a result, in these places, the metal is realized in broadening. An excess of metal is formed, which ultimately leads to the formation of sunsets. The parameters of the excess, its formation on the inner or outer surface of the shelves are determined respectively by the magnitude and direction of displacement.

The application of the method allows in a wider range to use the offset of the vertical and horizontal rolls to control the broadening of the shelves of channels without compromising the quality of the rolled products.

The method can be implemented in both rough and fine gauges. Pos. it is of fundamental importance, or if defects formed in rough gauges in the form of excess metal may in some cases be rolled out in subsequent passes (with a slight displacement of the vertical rolls), then in finished calibers rolling with displacement inevitably leads to the formation of these defects. Rolling is possible both in consecutive universal calibers with offset vertical rolls along or against the course of rolling, and with their alternation in the production of channels and other flange profiles.

Claims (1)

Invention Formula The way of rolling the levellers in the universal chamber, including regulation 0 five 0 the broadening of the shelves by the displacement of the boundaries of the deformation sites of the shelves vrr , n. valka.mi on the face of chchag.-: D1. f () of the wall of the horizon horizon .. lio go or against the run pr (); ,, 1ki, cht.1i ayush1: 11 with the fact that, in order to improve the quality of rolled products by previous (). against the formation of sunsets from an excess of metal with internal and external surfaces one by one at their base, the shelves at their base are locally recompressed on the joint deformation areas of the nOvTOK and the wall from the inside with a horizontal roller during rolling ke with the displacement of the center boundary; . L1 of the formation of the shelves during rolling and hai y / HHoii sides with vertical rolls of the roll mill with displacement of the boundary of the hearth. deformations of the shelves against the rolling course, and the cavities that are formed on this basis roll up on the remaining parts of the deformation areas of the shelves or walls, respectively, and shelves and walls. Phi2.1 (Direction I rolling. I L Phage. Phi2.5 7 R 2 Fi.2.6 0 "3.7 Fi, g. 8