SU1077673A1 - Rolling stand - Google Patents

Abstract

ROLLED STABLE, containing support rolls, installed with pillows in the beds, nikikiee devices, as well as hydraulic cylinders of bending of the support rolls, placed on their elongated necks outside of the beds, in order to simplify the system of operational adjustment of geometric dimensions and shape rolled by means of equal joint adjustment of the thickness and the transverse profile of the bending band of the support rolls, it is equipped with guides mounted outside of the rolls in parallel axles of rolls, and the hydraulic cylinders of the anti-cushion support rolls are installed in these guides with the possibility of (L moving along them and equipped with a drive for this movement. h "h 9 00

Description

The invention relates to the field of rolling production and can be used to improve the accuracy of geometrical dimensions and improve the quality of the shape of sheets and strips produced in continuous hot and cold rolling mills.

A known rolling stand in which the 1e strip is regulated when the pressure of the metal on the rolls fluctuates, is produced by using spacer cylinders mounted between the cushions of the support rolls L.

A disadvantage of the known stand is the impossibility of using hydraulic cylinders for operative adjustment of the transverse profile and strip shape.

A rolling stand is also known, in which the adjustment of the transverse profile and the strip shape is carried out with the use of hydraulic cylinders mounted between pillows 1M and work rolls 2.

The disadvantage of the stand is the inability to use the spacer cylinders for the operational control of the strip TOL01IN when the metal pressure on the rolls fluctuates.

A roll stand is known, including support rolls mounted from the p-bearing in the beds, pressure devices, as well as hydraulic cylinders for the anti-bending of the support rolls, dispensed on their elongated necks outside the bed frame H.

A disadvantage of the known rolling stand is the unequal joint control of the thickness and transverse profile of the strips when the metal pressure on the rolls fluctuates, which makes it necessary to equip the mill with two systems of automatic control of the thickness and transverse profile of the strip, complicating each other's work.

The purpose of the invention is to simplify the system of operative adjustment of the geometric dimensions and shape of rolled products by means of an equivalent joint adjustment of the thickness and the transverse profile of the strip by the bending of the support rolls. I

To achieve this goal, the rolling stand, containing supporting rolls installed with pillows in the beds, pressure devices, as well as hydraulic cylinders of anti-bending support rolls placed on their elongated necks outside of the beds, is provided with guides installed on the outer side of the rolls parallel to the axis of the rolls, And the anti-bend cylinders of the support rolls are mounted in these guides with the possibility of moving along them and are equipped with a drive for this movement, preferably a piston one.

It is known that profile distortion

and the deviation of the thickness of the rolled strips from a predetermined one is the result of a fluctuation of rolling force due to a number of technological factors. Automatic thickness control systems (CAPT) and profiles (SLRP) of modern broadband mills, which compensate for deviations of stripes from exact geometrical dimensions, operate independently of each other.

each, which complicates the work of each, reduces the speed of regulation.

It is also known that the method of counter-bending of the support rolls has the property of regulating both the transverse and longitudinal profile of the strips. However, the choice of the place of installation of the hydraulic cylinders for the anti-bending of the support rolls is carried out taking into account the conditions of strength of the rolls, the possible limits of adjustment of the strip sizes or the allowable efforts for the support roll rolls, which does not provide equal control of the longitudinal and transverse rolled profiles.

In this connection, it is possible to determine the installation position of the hydraulic cylinders for the anti-bending of the support rolls on the basis of equal control of the longitudinal and transverse profile of the rolled strip.

Figure 1 shows the layout of the hydraulic cylinders in the stands when rolling a strip of width B {without a mechanism for moving the hydraulic cylinders along the roll axes); on. FIG. Figure 2 shows the roll gap deformation in the process of adjusting the thickness and transverse profile of the strip; figs 3 and 4 show the mechanism for moving the anti-bend hydraulic cylinders along the roll axis.

The support rolls 1 and 2 (figure 1) with the help of pens 3 and 4 are installed in the beds5 of the quarto stand. The position of the upper support roll 1 when rolling a strip 6 of width B is determined by using devices 7, the distance of which is equal to the value of L. On the elongated necks of the support rolls 1 and 2, at a distance of € from the axes of the pressure devices 7, the hydraulic cylinders 8 of the bend are placed outside of the rolls, bursting additional curtains 9 of the support rolls.

The value of I is determined by the rolling of the elements according to (the formula

And p about

e

l l pi. L

where I is the deformation of the supports of the roller unit of the rolling stand when the rolling force changes by one unit;

. roll knot deformation

ti in its average cross section relative to sections that pass along the edges of the strip when the rolling force changes by one unit;

1. deformation of the rolling stand in the middle section of the roller unit when the rolling force is changed by one unit;

-Ti. deformation of the roller unit in the middle section relative to its supports when the moment of the bending of the support rolls changes by one unit;

pi

L), is the deformation of the roller assembly in the middle section relative to the sections passing along the edges of the strip when the moment of the bending of the backup rolls changes by one unit.

Equal adjustment of the longitudinal and transverse profile of the strip is carried out in the following manner.

In the process of rolling a strip of a given thickness h (Fig. 2) with a technological force P, the cross-sectional profile of the rolled product corresponds to a straight line 10. Transverse and longitudinal thickness variation is absent.

At a certain point in time, under the influence of a number of technological factors, the pressure of the metal on the rolls increases by dP. In this case, the profile of the strip corresponds to curve 11. The deformation of the rolling stand over the middle cross section of the roller assembly increases by d И Ic-yr, which causes the longitudinal thickness variation dh, and the deformation of the middle cross section of the roller assembly relative to the cross sections along the strip edges increases by dS value which determines the cross-section thickness of rolled 3 &

To correct the transverse thickness of the strip in the cylinders 8 (FIG. 1), a force c) F t is created that forms. - moment of bending

ZM EdF. (2)

The rolls are bent in the direction opposite to the pressure of the metal by the value of d6 aJ, d M, due to which the lateral thickness is compensated

dS.d5

(3)

OR

  Q chl.

At the same time, the deformation of the rolling stand over the middle cross section of the shaft assembly is reduced by

dh. d / -Ao-} PD

Residual longitudinal difference5 Unity of strip is equal to

cJh.jh-dh r-A c) (. (4)

Solving equation (4) with the help of expression (3) and taking into account (2) and (1),

0 get d h «O.

Consequently, the hydraulic jacks of the anti-bending device of the support points, located outside the rolls at a distance of

five

P

l lpi l pi -

FROM the axes of the pressing devices, they provide an equivalent prompt adjustment of the longitudinal and transverse profile of the strip. The profile of the strip corresponds to curve 12 (figure 2).

Placing hydraulic cylinders against bending of the support rolls at a distance other than E leads to the formation of residual longitudinal or transverse thickness variation, which requires the installation of a system for automatic adjustment of the strip thickness.

The values of A „; Lo-tL in 1 p P rolling of a given gauge are determined experimentally.

5 or theoretically.

I. ;.

Analysis of dependence (2) showed that the value of c is determined mainly by the width of the rolled strip. For example, when rolling a strip with a size of mm under the conditions of a continuous wideband mill of 1700 hot rolling with a technological force of 700 tons in the last stand of a continuous group of strain values when the pressure of a metal fluctuates. on the rolls are: I O, 002073 mm / t,: Not-O / 00783 mm / t, 1 "± 0.000265 / t and, as the moment of change is counter, 0 ga1 1,% 1,273.10 WM / Tm, A." 0.114-10 mm / t.mm, which allows determining the installation location of the anti-bending devices of the support rolls at a distance of 8–2070 mm from the axes of the clamping devices, whereas when rolling a strip with dimensions of f 1580 mm. In order to ensure equal control of the longitudinal and transverse profile of the strip along the shirin, the rolling stand is equipped with a mechanism for moving the cylinders of the anti-bending of the support rolls. The body of the hydraulic cylinders of the anti-bend 8 (FIG. 3.4) is placed in the guides 13 installed in the frame b parallel to the axis of the support roll 1, and connected to the LlTOKOM 14 of the hydraulic cylinder 15 mounted in the frame of the stand. The cushions 3 and 9 are rigidly connected to each other by the beams 16, on which the plungers of the 17 hydraulic cylinders of the bending rod 8 are supported. The device operates in a manner that follows. Before rolling a batch of lanes that accommodate the hydraulic cylinders of bending of the support rolls at a distance and from the axes of the pressing device, the working fluid is fed into the piston cavity of the hydraulic cylinder 15, DJTOK of which nepeMBLnaeT body of anti-bend hydraulic cylinders 8 along the guide 13 axes of the supporting rolls 1 and 2. As soon as the distance reaches a predetermined value, the piston cavity of the hydraulic cylinder 1 5 is closed, after which the strips are rolled. If it is necessary to adjust the transverse and longitudinal profile of the rolling stock under the action of metal pressure fluctuations on the JP rolls, the plungers 17 of the bending cylinders act on the bearing surfaces of the beams 16 with a force dM, forming a bend dM at the roll meike. At the end of the rolling of a batch of strip widths B, the pressure in the cylinders 8 of the roll bending is dropped and, using the cylinder 15, the bend device is moved to a new position for rolling strips of another gauge in width. The economic effect from the introduction of 1700 mill on one finishing stand will amount to 900 thousand rubles. in year.

Claims (1)

Rolling backup rolls, with cushions in the beds, pressure devices, as well as anti-bending hydraulic cylinders of the backup rolls, located on their elongated necks outside the beds, it is clear that, in order to simplify the system of operational regulation the geometric dimensions and shapes of the rolled by means of equal joint regulation of the thickness and transverse profile of the anti-bend strip of the backup rolls, it is equipped with guides mounted on the outside of the bed parallel to the axis of the rolls, and the hydraulic cylinders prot voizgiba support rollers are installed in these guides can be moved along them and provided · actuator this movement. SU 1077673 A Riga f