SU1544513A1 - Rolling mill roll - Google Patents

Abstract

The invention relates to the processing of metals by pressure and can be used on crimping and billet mills. The purpose of the invention is to improve the quality of rolled products by ensuring uniform deformation of the side faces. On the mill roll, the forming surfaces are made in the central part of the barrel in a section equal to the width of the rolled stock, according to the Cassini equation. 2 Il.

Description

The invention relates to the processing of metals by pressure and can be used on crimping and billet mills.

The purpose of the invention is to improve the quality of rolled products by ensuring uniform deformation of the side faces.

Figure 1 is given profiling rolls of the cage; figure 2 - form forming the roll in the Central part.

On the mill roll, the change in the profile of the generatrix of the surface is made in the central part of the barrel in a section equal to 0.6-0.7 of the generator length, according to the Cassini equation

z

(Xg + YV- 0.5 Xg + 0.5 L Y

 0.1250 + 0.165 0.0625L1r,

where X, Y - the coordinates of the points of the curve-forming;

WITH)

s

ov

oaC)

Le is the length of the forming barrel;

D - diameter of the barrel. The drawing shows: section I of the roll barrel length, made according to the Cassini equation, the shape of the side surface 2 of the roll with uneven distribution of the stretch, the shape of the side surface 3 of the roll of uniform distribution in the same section, the contact layer 4 of metal, the middle layer 5 of metal.

The peculiarity of making the surface of the roll barrel is that the generation of the generators according to the indicated dependence creates an uneven change in the coefficient of friction along the length of the barrel from the edge of the strip to its middle, with the smallest value of the coefficient of friction near the edge of the strip, and towards and then decreases again. This distribution

0

yo

S

4b SP

ABOUT

coefficient of friction allows you to influence the shape of the side faces of the car.

Fig. 2 shows the central part of the roll mill barrel, of a length L. The surface of this roll bar section is described by a curvilinear relationship (Fig. 2} o

To calculate this dependence, it is assumed that the inflection points B and C are located at a length of 0.33 L from the edge. The parameter is represented as a product of the absolute values of the distances from the foci Ft, FI to the inflection point B, i.e. a2 / / bfz |.

Considering that BF is 0.5D (where D is the barrel diameter), a is 0.66L, from flFjBF are found

I1g I

BF (- V0.5D + 0.66L 0,3D - a;

(3)

a - (0.5D + 0.661 /) 0, (4) a4 - 0.125D4 + O, 165I / D2. (5)

The value of C is taken equal to 0.5L, then C 0.0625 I /.

Substituting the original data in the equation, 30 some 1, get

1 t ig yy

(X + Y) - 0.5L X + 0.5L Y - 0.125 D + 0.165 0.06251.

(6)

one

In order to determine the flowing diameter on the curvilinear forming drum on the section AB, it is necessary to substitute the current value of the coordinate along the X axis, which varies in the range (0-0.35) L, the length of the barrel L, its diameter D.

Solving the obtained biquadratic equation, find the values of the current diameter Dj, D2 ,, с, D,

The rolling of ingots in rolls with a roughness distribution in the central part of the barrel length according to the Caesini equation makes it possible to eliminate the elongation and broadening of the metal only in the places of its contact with the rolls. The middle (mute-deformable) layers are entrained due to the flow of the near-contact layers, and the cross-section of the roll is distorted due to a complex deformation pattern, with uneven distribution of stretching (Fig. 1).

-

Q 5

0

five

0

35

40

45

50, 5

The distribution of the surface profile according to the Cassini equation contributes to the creation of a stress-strain state scheme with a more uniform deformation and a straight configuration of the side faces of the roll. This is especially important in the task of rolling out with a smooth barrel for subsequent rolling in a sliding caliber. Due to a more uniform deformation along the contour of brooks of calibers, a decrease in internal stresses is achieved, leading to the formation of wrinkles and overflow of calibers with the appearance of podrečov and sunsets. In addition, when rolling on a smooth barrel, ingots of low-grade steel grades, as well as having a low heating temperature, to obtain a correct cross section of the roll, it is necessary to increase the number of castings and reduce the reduction per pass, which reduces the productivity of the mill. The proposed mill roll design reduces the influence of these factors on the geometry of the roll.

PRI m e RO Roll swath mill can be prepared as follows. For example, the barrel length L 2400 mm, diameter D "920 mm, substituting these data into equation 6, and also changing the coordinates along the X axis in the interval (0 - 0.35) L, find that the change in the barrel diameter in the section of Cassini Curve lies within 800-870 mm at the distance AB and further decreases to 850 mm in the section BB0. At a section of 0.3 L, symmetrically located in the center of the barrel, it is rolled up by grooved rollers with a trapezoidal shape of the reef. Then, on a length of 0.2 L, high rollers are welded, and smooth turning at the edges of the barrel,

o The combination of roughness distribution along the length of the forming roll barrel with the curvilinear diameter variation helps to reduce the non-uniformity of deformation over the cross section of the strip and to improve the quality of the blanks.

Rolling roll works as follows ,,

By increasing the friction of the contact of the working surface of the barrel, equal to 0.6-0.71, with applied reef and hardness, a stable gripping of an ingot of square or ave. 515 is provided.

angular section. As the deformation zone is filled, the middle layers of the roll are subjected to more intensive plastic deformation due to greater force on the rolls in the middle part of the barrel length. The contact layers are less restrained by the middle of the roll and receive a more intensive stretching, which helps to reduce the broadening of the contact layers. Most of the compressed metal goes to the draw, which contributes to obtaining the correct shape of the cross section of the roll and reduces the unevenness of the reduction in subsequent passes across the width. brook caliber. This reduces the likelihood of defects of rolling origin (wrinkles, undercuts, sunsets) on blooms.

136

a smooth barrel of the blooming mill, to improve the surface quality of the blooms, to reduce the scrap in the production of tubular billets by 25%, to increase the yield of good.

Claims (2)

Invention Formula A mill roll containing a barrel with a non-uniform length of roughness and a wavy forming and neck, characterized in that, in order to improve the quality of the workpiece by ensuring uniform deformation of the side faces, which is formed by the equation: 2. yy yy (X + Y) - 0.5BBH + 0.5Lt Y О, 1250Y + 0.165L 0.0625b, mm Using the proposed pro-where X, Y - the coordinates of the points of the curve the roller roller allows for forming; favorable scheme of deformation of the metal during rolling in the first passes to L is the length of the forming drum, m but D - barrel diameter, mm. XT-Vbrtf. L is the length of the forming drum, mm { but D - barrel diameter, mm. Ф143.1 Jx X / X X 5 X Compiled by V. Znselman. Editor L. Zaitseva. Tehred A. Kravchuk. Corrector M. Naksimishinets  456 Circulation 410 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 AT / / / / Al 3 X -  M5L 0.5 L FI.2. Subscription