RU2357820C2 - Roller guide - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: invention refers to rolling mill industry, particularly to designs of roller guides and can be implemented in section and wire mills. The roller guide for entry of rounded band into the section mill stand contains pair of non-driven rollers, arranged opposite to each other and secured so, that distance between axes can be altered. Circular U-shaped cuts are made on cylinder surfaces of the rollers. Each of sides of the circular cut is made curvilinear with radius of curvature 0.7-1.1 from thickness of the band and coupled with rectilinear section of the cylinder generatrix along the circumference arc. Additionally, radius of coupling arc of circumference is 0.3-0.5 from radius of curvature of side of the circular cut.

EFFECT: upgraded quality of section band and eliminating its jamming in mill.

2 cl, 1 tbl, 1 dwg

Description

The invention relates to rolling production, in particular to designs for lead-in roller wiring, and can be used on high-quality and wire mills.

Known introductory roller wiring of the rolling stand, comprising a housing in which passes are located, roller holders with rollers and means for adjusting their position in the form of a flare nut. In addition, the roller wiring is equipped with hydraulic cylinders, the rods of which interact with the end of the flare nut [1].

The disadvantage of this roller wiring is that it does not provide reliable retention of the position of the strip of oval section before entering the caliber. As a result of this, there is a distortion of the profile of the varietal strip, its jamming in the mill is not excluded.

Also known is the design of the lead-in roller wiring for introducing the strip into the stands of high-quality and wire rolling mills, comprising a housing, inside of which lever-type roller holders are mounted, on the fixed axes of which non-drive compound guide rollers are mounted on rolling bearings [2].

Such wiring does not provide reliable retention of the strip of oval section along the axis of the caliber. This degrades the quality of the strip and leads to its jam in the mill.

An analogue to the present invention is a roller wiring for introducing a rounded strip into the stand of a rolling mill, containing a pair of non-driven rollers located opposite and fixed in the roller holders with the possibility of changing the center distance. On the cylindrical surfaces of the rollers, U-shaped ring cuts are made. The generatrix line of the U-shaped incisions is a part of the circular arc [3].

The disadvantages of wiring this design are that it does not provide reliable retention of the position of the strip of oval section along the vertical axis of the caliber. “Stalling” (turning about the horizontal axis) of the strip before entering the gauge leads to distortion of shape and degradation of the quality of the varietal strip, its jam in the mill.

The technical problem solved by the invention is to improve the quality of the varietal strip and the exclusion of its jams in the mill.

To solve the technical problem in the known construction of the roller wiring for introducing into the cage of a rolling mill a rounded strip containing a pair of non-driven rollers located opposite and fixed in the roller holders with the possibility of changing the axle distance, on the cylindrical surfaces of which ring cuts of a U-shape are made, according to the invention each of the lateral sides of the annular cut is made curved with a radius of curvature of 0.7-1.1 of the strip thickness, and paired with a linear section of a cylindrical generatrix along an arc of a circle. In addition, the radius of the mating circular arc is 0.3-0.5 of the radius of curvature of the side of the annular cut. The essence of the proposed technical solution is illustrated by the drawing, which shows the roller wiring, front view.

Roller wiring consists of a non-driven upper roller 1 mounted using bearing bearings on an axis 2 fixed in the upper roller holder 3, and a non-driven lower roller 4 also mounted using bearing bearings on an axis 5 fixed in the lower roller holder 6. Upper roller holder 3 and the lower roller holder 6 is fixed in the roller wiring housing (not shown) with the possibility of movement when the set screws are rotated, thereby changing the center distance opposite located upper roller 1 and lower roller 4.

On the cylindrical surfaces of the upper roller 1 and the lower roller 4, annular U-shaped cuts are made. The lateral side of each annular cut is curved with a radius of curvature R of 0.7-1.1 of the thickness B of the strip of oval section, and is associated with a rectilinear portion of a cylindrical generatrix in a circular arc with a radius r. The radius r of the mating circular arc is 0.3-0.5 of the radius R of the curvature of the side of the annular cut.

In its effect on the oval strip, the roller wiring acts like an overturning roller, which ensures the strip self-aligns strictly to a predetermined position along the gauge axis: in the case of a deviation of the larger oval axis from the vertical from the side of the U-shaped ring cuts of the upper 1 and lower 4 rollers, the strip starts Influence a pair of oppositely directed forces that return the strip to a predetermined position. Moreover, if the oval strip enters the roller wiring with a significant inclination of the larger axis of the oval to the vertical, the sections of the conjugation of annular cuts along arcs with a radius r, acting on the side surfaces of the strip, reduce its initial inclination.

It was experimentally established that if the curved lateral side of the annular cut is made with a radius of curvature R> 1.1 · B, then the opposed forces arising at the contact of the strip with the walls of the U-shaped cuts on the barrels of the upper 1 and lower 4 rollers are not enough to return a long the axis of the strip with an oval cross-section in a vertical position, which will lead to the “stalling” of the strip in the gauge of the rolling stand and its quality deterioration. If R <0.7 · B, then the oval-shaped strip will be pinched in the U-shaped annular grooves of the upper 1 and lower 4 rollers, rotation around the longitudinal axis and self-adjustment of the strip position will become impossible. This will lead to “stalling” of the strip in the gauge of the rolling stand, jamming of the strip in the mill due to its deviation at the exit of the stand from the rolling axis.

It has also been experimentally established that for r> 0.5 · R, ring incisions of the U-shape of the upper 1 and lower 4 rollers do not provide alignment of the strip at the entrance to the roller wiring with a deviation of the major axis of the oval from the vertical. When r <0.3 · R, it is possible that the strip is poked into the mating sections with the radius r of the rollers 1 or 4 and the strip is stuck in the mill.

The device operates as follows.

For the task in the caliber of a strip of thickness B = 56, having a section in the form of a flat oval, use roller wiring with two opposed non-drive rollers 1 and 4 with ring incisions in a U-shape. Each of the sides of the annular cut is made curved with a radius of curvature R = 50 mm, i.e. R = 0.893B. The curvilinear lateral sides of the annular cuts are conjugated with rectilinear sections of cylindrical generators along circular arcs with a radius r = 0.4 · R = 20 mm.

Using the set screws, the roller holders 3 and 6 are moved relative to each other with the axles 2 and 5 of the rollers 1 and 4 fixed to them. This sets the interaxial distance between the upper 1 and lower 4 rollers to pass the oval section strip with a larger oval axis equal to 116 mm To correctly set the center distance use a template.

Roller wiring is fixed on the input side of the 3rd stand of mill 150 strictly along the axis of the open box caliber.

A heated steel billet with a section of 100 × 100 mm in two passes in the roughing stands of mill 150 is crimped into a strip with a thickness of B = 56 mm, a width of 116 mm and a cross section in the form of a flat oval. After tilting 90 degrees with the overturning rollers, the strip is pushed between the upper 1 and lower 4 non-driven rollers, which rotate on the axes 2 and 5, fixed in the respective roller holders 3 and 6.

When the front end of the strip enters the gap between the rollers 1 and 4, their peripheral sections with roundings of radii r, sliding along the lateral sides of the strip, center it and turn to decrease the angle of deviation of the major axis of the oval section from the vertical (rough installation). Then the rounded sections of the strip come into contact with the curved sides of the U-shaped annular cuts, the radius of curvature of which is R = 50 mm. When interacting with the curvilinear lateral sides of annular incisions with a pushed strip, a pair of oppositely directed forces occurs, under the action of which the strip is rotated in the direction of decreasing the angle of deviation of the major axis of the oval section from the vertical (precise setting).

After gripping, the strip is pulled by rolls of the 3rd stand through non-driven rollers 1 and 4, which rotate on bearing bearings around their axles 2 and 5, mounted in roller holders 3 and 6. Rollers 1 and 4 with their curved sides of the ring cuts set the strip relative to the vertical and horizontal axes of box caliber. As a result, the strip enters the box gauge of the 3rd stand exactly along its axis, which eliminates the “stalling” of the strip during compression in the gauge, and its jam in the mill is excluded.

The table shows the options for performing roller wiring and indicators of their effectiveness.

Table No. R: B r: R Out of Non-Condoms. rolled% Strip jams in the mill one. 0.635 0.2 8.35 presence. 2. 0.700 0.2 1.32 absent. 3. 0.893 0.4 1,08 absent. four. 1,100 0.5 1.29 absent. 5. 1,178 0.6 8.61 presence. 6. not regl. not regl. 10.5 presence.

From the data given in the table, it follows that when the proposed ratios R: B and r: R (options No. 2-4) are fulfilled, an increase in the quality of the varietal strip is achieved and jamming of the strips in the mill is eliminated. With transcendental values of these ratios (options No. 1 and No. 5), as well as when using the prototype device (option No. 6), the quality of the varietal strip deteriorates, and the jam in the mill is not excluded.

The technical and economic advantages of the proposed roller wiring are that it provides accurate self-installation of the rounded strip in the gap between the non-driven rollers, its exact entry along the axis of the caliber of the rolling stand. As a result, the distortion of the strip shape is reduced, the quality of the stripes is improved, and jamming in the mill is eliminated.

The use of roller wiring of the proposed design will increase the profitability of the production of long products by 2-3%.

Literary sources

1. Autosvid. USSR No. 1378972, IPC B21B 39/16, 1988

2. Autosvid. USSR No. 958001, IPC В21В 39/16, В21В 38/00, 1982

3. RF patent No. 2221658, IPC В21В 39/16, В21В 38/00, 2004

Claims (2)

1. Roller wiring for introducing a rounded strip into the stand of a section rolling mill, comprising a pair of non-driven rollers located opposite and fixed in roller holders with the possibility of changing the axle distance, on the cylindrical surfaces of which ring-shaped incisions are made in a U-shape, with each of the sides of the ring incision made curvilinear with a radius of curvature of 0.7-1.1 of the thickness of the strip, and paired with a rectilinear section of a cylindrical generatrix along an arc of a circle. 2. Roller wiring according to claim 1, characterized in that the radius of the mating circular arc is 0.3-0.5 from the radius of curvature of the side of the annular cut.