SU1503913A1 - Vertical roll set-up for wide-strip hot rolling mill - Google Patents

Abstract

The invention relates to the processing of metals by pressure, in particular to sheet-rolling production, and can be used in the preparation of strips, preferably in wide-strip hot rolling mills. The purpose of the invention is to increase mill productivity and rolls durability by reducing the dynamic factor at the moment of rolling up and reducing the effort when slamming the ends of the slabs. In the complete set of vertical rolls on the barrel of each ring rims are made. The depth of the annular stream along the circumference of the roll barrel is made variable with the axis of the center forming the bottom of the stream and eccentric relative to the axis of rotation of the roll. The magnitude of the eccentricity relative to the axis of rotation of the roll is determined from the relationship. Also, the distance between the axis of rotation of the roll and the axis of the roll barrel is determined from the relationship. During operation, the slab is fed into the stream gap between the rollers. In this case, slab is set on the value, starting from the end, equal to the value of the required crimping of the slab end. After that, the set of rolls is rotated and the slab moves in the opposite direction to the preliminary task of the slab in the strand gap. 1 hp f-ly, 5 ill., 1 tab.

Description

The invention relates to the processing of metals by pressure, in particular to sheet-rolling production, and can be applied in the preparation of strips, preferably in broadband hot rolling mills.

The aim of the invention is to increase the productivity of the mill and

roll bones by reducing the coefficient of dynamism at the moment of seizing the rolled stock and reducing the effort during compression of the ends of the slabs.

Figure 1 presents a set of vertical rolls, a General view; - figure 2 - roll set; fig.Z - the same, conditional section; figure 4

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slab, crimped at the ends with a set of rolls, plan view; figure 5 - scan profile ridge along the bottom of the stream. .

In the set of vertical rolls of a wide-strip hot rolling mill: the depth of the annular stream around the roll barrel is variable with the axis of the center of the bottom-forming stream eccentric relative to the axis of rotation of the roll. The goal is also achieved by the fact that the eccentricity of the axis of the center of the bottom-forming stream relative to the axis of rotation of the roll is determined from the dependence

e-C.R.,

where e is the eccentricity value of the axis of the center of the bottom-forming stream relative to the axis of roll rotation, mm; С - coefficient of proportionality (0.05 С 0.20); Rg is the bottom radius of a vertical roll stream, mm. The distance between the axis of rotation of the roll and the axis of the barrel of the vertical roll is determined from the relationship: 1 e (R / Rg) with the axis of the roll, the axis of the center forming the bottom of the gauge and the axis of the barrel forming the vertical roll are in one plane ; 1 is the distance between the axis of rotation of the roll and the axis of the barrel of the vertical roll, mm; e is the eccentricity value of the axis of the center forming the bottom of the stream relative to the axis of rotation of the roll, mm; R is the radius of the barrel shaft, mm; Rg — bottom radius of a stream of vertical Alca, mm; m is the exponent ().

A set of vertical rolls of a wide-strip hot rolling mill (preferably for shaping the ends of the slab) includes a pair of vertical rolls, each of which has circular bands.

The set of vertical rolls of a wide-strip hot rolling mill includes a pair of vertical rolls 1 and 2, each of which has a barrel 3 and a gang 4. On the barrel of each of the rolls e with radius R, annular streams are filled. The depth H of the annular stream is variable (from W to W) with a profile varying from ABCD to EFGH. In this case, the axis KK center forming. . the bottom of the stream BC (FG) radius R is located eccentrically at a distance e

five

91

d 5

0

About 5 0

five

34

relative to the axis of rotation of the roll Y-Y.

. Velich: ina of this eccentricity e is determined from the expression:, where e is the eccentricity value of the K – K axis of the center forming the bottom of the stream relative to the Y – Y axis of rotation of the roll, mm; С - proportionality coefficient (0.05 С 0.20); Rg is the radius of the generator VS (FG) bottom of the roll stream, mm. In addition, the magnitude of the distance 1 between the axis of rotation Y-Y of the roll and the axis L-L. forming the roll barrel is determined from the expression: 1 e (R / Rj), where 1 is the distance between the Y-Y axis of the roll rotation and the axis to L-L forming the roll barrel, mm; e is the eccentricity value of the axis К-К of the center of the stream forming the bottom relative to the axis Y-Y of rotation of the roll, mm; R is the radius of the forming roll barrel, mm; R0 is the radius of the stream forming the bottom, mm; m - exponent (1 .t 3). The axis of rotation of the roll Y-Y, the axis of the center of the stream forming the bottom (caliber) K-K, the axis of the barrel forming the vertical roll L-L are placed in the same plane - along the 0-0 axis.

. A set of vertical rolls works as follows.

Sl 5, with its head end 6, is placed in the joint gap between the set of vertical rolls. Moreover, each of the sets of rolls 1 and 2 is turned in such a way that the distance between the creeks along their bottom is greater than the width of the slab. This is achieved when all three Y-Y, K-K and L-L axes are. Roll set 1 and 2 are aligned and are in the same plane defined by the 0-0 axis. When the slab is mounted on the photosensor for a given distance of 1, a pair of forks begin to turn (in the direction of the arrow or o) around the Y-Y axes. .The distance between the vertical rolls along the bottom decreases, until the slab begins to be wound across the width and it moves in the direction indicated by the arrow 11: o r. The width deformation of the slab begins smoothly, which is ensured by the pattern of sweep forming the bottom (figure 5), and as the backward movement of the slab the given degree of deformation increases, and so on until slab 5 comes out of contact with the streams of vertical rolls 1 and 2. Then rolls 1 and 2 you 51503

put in the zero position when all three Y – Y, K – K and L – L axes are located in the same plane with the pair of rolls 1 and 2. They form the maximum gap between the rolls along the bottom of the stream, and slab set this gap with their

tail 7. At this point, the axis of the set of vertical rolls 0–0 is aligned with the cross section of the P – P slab, after which the rolls begin to rotate in the direction of arrow T (i.e., in reversing mode relative to the head end of the slab, when their rotation was along arrow 6), when reaching contact with the stream, the slab begins to be crimped and it moves reciprocatingly (which is indicated by an arrow in FIG. 3) until it comes out of contact with the streams of a set of vertical rolls 1 and 2. In the transverse section as a result of compression, slab 5 acquires the form shown in figure 4. After this th slab 5 is set in subsequent roughing stand subjecting compression width throughout its length to the desired value by the known schemes in combination with iron-rolling passes and E in horizontal rolls in thickness.

A set of vertical rolls for reducing the dynamic factor at the moment of rolling up the rollers and reducing the efforts when profiling the ends of slab the depth of the annular stream along the circumference of the roll barrel is made variable with the axis of the center of the bottom forming stream eccentric with respect to the axis of rotation of the roll. The value of the eccentricity of the axis of the center forming the bottom of the stream relative to the axis of rotation of the roll is determined from the dependence

C-R

at

(I)

where e is the eccentricity value of the axis К-К of the center of the stream forming the bottom relative to, the axis of rotation Y-Y of the roll, mm; C is the proportionality coefficient (0.05 C &0.20); Rg- radius forming the bottom of the stream

vertical roll, mm. When executing equation (1) we proceed from the fact that, on the one hand, to provide the required amount of squeezing, the value of the coefficient C depending on the required squeeze amount of slabs is within 0.05 С 0.20, the minimum value

45 С 0.05 corresponds to a small reduction in slab width when profiling, providing the required shape of the end portion of the slab and the amount of profiling by parameters a and 1, Mac

5Q is the maximum value, 20 corresponds to a large reduction of slab widths when profiling the ends of slabs. A change in the value of the coefficient C within the specified limits provides

It is slab wide, and on the other hand, 55 are the most optimal shapes and sizes of profiled sections of slabs, which reduce the dynamic coefficient at the moment of the capture of rolled rollers and the effort during the profiling itself. With

It is possible to place pillows with bearings on the roll, i.e., e, two requirements are combined: technological and structural.

In addition, the distance between the axis of rotation of the roll and the axis of the barrel of the vertical roll is determined from

1 e (K / KV) p, (2)

where 1 is the distance between the Y – Y axis

rotation of the roll and the axis of the barrel forming a vertical roll, mm;

e is the eccentricity value of the axis of the center forming the bottom of the stream relative to the axis of rotation of the roll, mm;

R is the radius of the roll barrel, mm;

R-- bottom radius stream vertical

whom roll, mm;

m is the exponent (). When executing equation (2), it was guided by the principle that the value of the closed stream should be as large as possible (1.,) to compress and form the end of the slab. This is achieved by the parameter of eccentricity,

which increases with the ratio of the two radii R / R g and the exponent.

 The axis of rotation of the roll Y-Y, the axis of the center

forming the bottom of the caliber K and the axis

barrels vertical roll L placed in one plane. The expediency of choosing the expressions () and (2) is explained by the fact that they most accurately approximate the experimental data obtained in the simulation of slab end shape profiling to reduce dynamic loads when the slabs are captured by rolls during rolling and to reduce effort

Profiling

At the same time, the value of the coefficient C, depending on the required value of slab reduction, is within 0.05 С 0.20, the minimum value

С 0.05 corresponds to a small rolling of widths during the profiling, providing the required shape of the end portion of the slab and the amount of profiling on parameters a and 1, the maximum value, 20 corresponds to a large reduction of the slabs of width to width when profiling the ends of the slabs. the value of the coefficient C within the specified limits provides

“The most optimal shapes and sizes of profiled slabs, which reduce the coefficient of dynamism at the moment of the capture of rolled rollers and the effort during the profiling itself. With

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From 0.05 during the slab profiling in the proposed device, it is impossible to obtain the required dimensions of the profiled sections, and at C 0.20, the strength properties on the vertical roll deteriorate, which can lead to an accelerated release of it.

The value of the coefficient m in expression (2) is within It.З. The minimum value up to is taken when profiling relatively narrow slabs and corresponds to the minimum possible depth of the stream, when the protrusions with the shape of the dog move the bone, to the center of the roll when it is profiled and have a small height, which reduces the dynamic loads during the subsequent rolling in horizontal cage x. The maximum value up to is taken when profiling wide slabs and corresponds to the maximum depth of the stream that prevents bending of the slab during profiling and reduces high that projection of a canine bone type t. When a 1, in the course of profiling, at the ends of the slab, significant thickenings in the form of a dog are formed and the slabs are bent, which increases the dynamic loads during the gripping of the slabs during the subsequent rolling and, as a result, decreases the productivity. The increase in t 3 leads to a significant increase in the dimensions of the roll and to reduce its resistance.

With the practical use of the kit, the character of the change in the gap between the vertical rolls during their rotation provides a different shape of the shaped section of the slab (concave, straight, vertical). To obtain the desired shape of the deformed section of the deformation of the end portion of the slab, an integral at a certain initial angle (rotation of the vertical rolls. So, for example, to obtain at the front end of the slab of the profiled portion of a straight line shape, 60, , vertical rolls at an angle up to 60 ° inclusive, to obtain a concave shape of the section to be profiled (2Q ° and convex - C, - 0. By choosing the angle Lf, and the angle of rotation of the vertical rolls, you can get

eight

the combination of these forms of the shaped area,

 The table shows the results of testing known and proposed

sets of vertical rolls on lead models (size 17x100x x150 mm),

Example. The choice of the optimal boundaries of the coefficient C and the exponent m was confirmed by the results of statistical processing of a planned experiment of the type 2 Sith values, implemented on the abtorrator model with a scale of 1:15 decrease using

vine samples (table). As follows from a comparative analysis of the data obtained using the proposed kit and well-known, in the whole range of boundary values of the parameters 0.05, 20 and 1 4t f 3, smaller magnitudes of efforts are obtained when capturing rolled products, i.e. the dynamics and forces during rolling decrease so that the maximum reduction in dynamics is 74%, and in the period of the established process 12%. This advantage of the proposed set corresponds to the optimal average values of the parameters C and w. A decrease in the dynamics can be regarded as an exception to such a factor as the roll slip relative to slab, which reduces the productivity of the mill in the roughing stand group to 3%. The reduction of rolling effort by 12% can be considered as a factor contributing to the improvement of the performance and durability of the roller unit. Where the bearing efficiency factor is determined by

Кр (Р, + 0,6А) 2,5 (n.h), (3) where, A - radial. E and axial - forces acting on bearings;

n - the number of revolutions of the bearing per minute, min; h - the durability of the bearing, h

For two rolling conditions, based on the fact that k p. and are constant for the same roll or bearing. ka can be written on the basis of (3) ratio

1--.:ili2i6Ai. xhisO.j P ,, 4-0,6AV h /

(four)

where the subscripts 1 and 2 designate two rolling conditions, for example using the known and proposed kits. If we consider that for one roll, the axial and radial forces are interrelated by the expression a, then expression (4) can be converted to the following form

b h ,, / h, (P ,,, / Py), (5) where b is a relative indicator

increase the performance (durability) of the roller unit on the maximum effort parameter for two compared sets of rolls.

As follows from the data obtained by formula (5) (table), the resistance of the proposed set is better than the known 1.50 times. This factor can be considered as a reduction in repair time, which, in general, improves the performance of the proposed device.

Claims (2)

1. A set of vertical wide-strip rolls, a hot rolling mill, the barrels of which are made with ring brooks, characterized in that, in order to increase the mill's productivity and durability of the rolls by reducing the dynamic coefficient at the moment of rolling pick-up. 0 0 ; The sequence, I, the depth of the circular stream of the roll barrels are made variable with the center of the circle forming the bottom of the gauge, which is eccentric relative to the axis of rotation of the roll and determined from the relation e C-Rp, where e is the eccentricity value between the center of the circle forming the bottom of the gauge and the axis of rotation of the roll; C - proportionality coefficient (0.05, 20); R is the radius of the circle forming the bottom of the caliber. 2. Complex TPP.1, characterized in that the forming roll barrels are made with the center of a circle, located with eccentricity relative to the axis of rotation of the roll, determined from the dependence 1 e R / t where 1 is the distance between the axis of rotation of the roll and the center of the circle forming the roll barrel; R is the radius of the roll barrel; m is the exponent (1 im 3), with the centers of the circles forming the bottom of the gauge and roll barrel, the first axis of rotation of the roll are in the same plane, while the centers of the circles forming the bottom of the gauge and roll barrel are offset from the axis of the roll the side. / K V V to L 1 L to V ffJLfS, 3 Phie. FIG. five 360 f, 2rod