SU770576A1 - Rolling mill working stand - Google Patents

Description

The invention relates to the field of metal forming and relates to the improvement of the working stand, in which for the production of round products by cross-rolling, there are difficulties in extending the range of control of the caliber and, consequently, technological capabilities.

A working stand of a rolling mill is known, containing a frame with two pairs of movable drums arranged around a rolling axis, equipped with pressure mechanisms and five bearing supports with rolling rolls 15, forming a gauge with a pinch common to all rolls [D) ·

Such a cage is intended for pipe rolling, with a pair of primary gauge rolls 20 flashing a solid billet on an amendment, and a pair of auxiliary gauge rolls performing transverse rolling of the tube on a mandrel.

A disadvantage of the known stand is that such a stand is designed for hot rolling of pipes.

In relation to the conditions of cold cross rolling calibration and mode of compression of the first in the course of rolling

2

A pair of rolls of this cage can be chosen such that the negative effect of the influx of metal on the performance will be eliminated (this is possible, if compression is small, within 10 ...

20% and the angle of the inlet cone of the roll is approximately 15 °). The angle of the output cone of the roll of the first pair is selected within 0 ... 3 ⁰ , thanks to which the first pair of rolls, acting as an auxiliary gauge, compresses the influx of metal arising from the action of the second pair of rolls forming the main gauge.

As for the diameter of the rolled pipe, then theoretically the minimum size of the pipe that can roll a well-known stand with the given sizes of the auxiliary and main pair of rolls will be

where 8 is the diameter of the pipe;

0 - diameter of the main pair of rolls;

- diameter of the auxiliary pair of rolls.

For example, if ϋ = 400 mm,

p <= 100 mm, then 8. = 70 mm. Practically

3

770576

four

ki this size is about

90 .. .100 mm, since it requires the placement of bearing supports for the perception of a relatively large force, usually constituting during the rolling of pipes with a diameter of 60 ... 80 mm with a wall

5 .. .10 mm not less than 7 ... 10 t.

Therefore, the known stand does not allow to expand the range of adjustment of the caliber and the technological capabilities of the production of round products by cross rolling.

The main disadvantage of the known stand is that it has a limitation of the range of regulation of the caliber in the direction of its reduction, and therefore does not allow to expand technological capabilities.

For example, for rolling a small pipe diameter (up to 50 mm), the size of the roll barrels and, accordingly, their bearings, is required to reduce

it is significant that their strength characteristics become unacceptable for the implementation of the cross-rolling process.

A further disadvantage of such a crate is shown in ^- low productivity pry "'embodiment of the transverse cold-rolling, due to the influx of formation of the metal at the beginning of the roll nip formed by rolls..

Known working stand of the rolling mill, containing placed in the frame two pairs of movable drums with the mechanisms of their movements and set-. The work rolls, forming the main gauge, and the work rolls with axes inclined to the axes of the drums, forming an auxiliary gauge [2].

The aim of the invention is to expand technological capabilities by expanding the range of regulation of the auxiliary caliber.

This goal is achieved by the fact that the work rolls that form the auxiliary caliber are fixed in supports in console and made in the form of discs having face and conical working surfaces, and the angle of inclination of the axes of the work rolls forming the auxiliary caliber to the axes of the drums is 10-20 * , the maximum ratio of the largest diameters of the work rolls forming the auxiliary caliber to the roll diameter of the main gauge is 5 '.

FIG. 1 shows a general view of the cage "; figure 2 - section aa in figure 1.

The proposed working stand of the rolling mill includes a frame 1 with two pairs of movable drums 2 and 3 arranged around the axis of rolling. Each drum is provided with a pushing mechanism 4, for example hydraulic. One pair of drums 2 has bearing supports 5 and 6 with rolls 7 forming the main gauge with parallel rolls. In the second pair of diametrically opposed drums 3, the bearing supports 8 form at an angle of about = 10 ... 20 ° to the longitudinal axes of these drums cantilever mounting of the supporting axes 9 for the rolls 10 of the auxiliary caliber biased along the rolling axis from the main caliber. Each roll 10 has the form of a disk with face "a" and conical "b" working surfaces.

ABOUT

The rolls 7 of the main caliber are made in the form of interchangeable barrels with a ratio of their diameter to the diameter of the rolls 10 equal to 3 ... 5.

During operation, the sleeve rotating together with the mandrel is set in the cage and immediately falls into the auxiliary gauge formed by the rolls 10 mounted on the supporting axes.

In this caliber the sleeve is pre-rolled with compression to 10%. . . 20%, then falls into the main gauge, offset by the rolling axis, formed by the rolls 7. Before the ridge of the rolls 7, for each rolling cycle there is an influx of metal, but it is immediately rolled out by the conical working surface “b” of the rolls 10 of the auxiliary caliber. Therefore, the effect of metal influx on the performance in this stand is eliminated.

To implement the profiling of blanks according to a given work program, hydraulic pressure mechanisms 4 are activated. In this case, without changing the rolls of the main and auxiliary calibers, a wide range of gauge control is provided.

In the present invention, the diameter of the rolls 7 of the main caliber is 450 mm; the diameter of the rolls 10 auxiliary caliber is equal to · 100 mm; diameter of rolled products is equal to _d

50 ... 300 mm.

The economic effect from the use of the proposed working stand will be approximately 100 thousand rubles.

Claims (1)

Claim The working stand of the rolling mill, containing two pairs of movable drums with mechanisms of their movements and installed in the drums by means of bearing supports work rolls forming the main gauge and work rolls with axes inclined to the axes of the drums, which form an auxiliary gauge, characterized in that in order to expand technological capabilities by expanding the range of regulation of the auxiliary caliber, the work rolls forming the auxiliary caliber are fixed five 770576 6 disputes are cantilevered and made in the form of discs having face and conical "working surfaces, and the angle of inclination of the axes of the work rolls forming the auxiliary caliber to the axes of the drums is 10-20 °, with the maximum ratio of the largest diameters of the work rolls forming auxiliary caliber, to the diameter of the rolls of the main caliber is 5.