JPS6320106A - Roll structure of rolling mill - Google Patents

Abstract

PURPOSE:To permit reduction of a difference in roll diameter, prevention of the generation of roll marks, etc., and smooth sheet crown control by forming a pair of work rolls to the contour of the expression of third order having the max value and min. value. CONSTITUTION:The roll contour of the upper and lower work rolls 1, 1' of a rolling mill is provided with the contour of the expression of third order having the max. value points 5, 5' and min. value points 6, 6' via inflection points 4, 4 in the barrel length thereof. The contours of a pair of the rolls are formed in point symmetry and the relative positions thereof are axially moved by which the sheet crown is steplessly adjusted from a flat shape to a recessed shape. The crown change range of 1mm is given and while the difference in the roll diameter is 6.05mm with the contour of the expression of second order, the difference is considerably decreased to 1.796mm with the contour of the expression of third order if the roll contour of the expression of third order mentioned above is adopted. The generation of roll marks, etc., are thereby prevented and the smooth sheet crown control is permitted.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The disclosed technology belongs to the technical field of the external structure of a roll such as a work roll installed in a rolling mill to perform the rolling of a steel plate.

<Summary of the gist> The invention of this application is to provide a roll pair of work rolls which are installed on the stand of a rolling machine via metal chocks, and an intermediate roll or an external roll of a reinforcing roll is arranged above and below the roll pair of work rolls. This invention relates to a roll structure for a rolling mill, in which one of the pairs of rolls has a curved roll profile over the entire length of its barrel, and in particular, one of the pairs of rolls has a curved roll profile over the entire length of its barrel. The roll contour consists of cubic, linear, and constant terms, and is a cubic equation related to the length distance in the barrel direction of the roll. The roll profile of the other roll is formed in point symmetry with respect to one barrel, including the parallel movement portion in the mutual barrel length direction, and furthermore, the roll pair is axially fixed roll. Rolls of a rolling mill that are movable in the axial direction relative to each other, and are formed so that the entire length of the barrel of the pair of rolls that have moved is longer than the barrel length of the fixed roll in the axial direction, and that even after the movement, the end portion of the roll remains outside for a longer period of time than the barrel length of the roll that is fixed in the axial direction. This invention relates to a structure.

<Prior art> As is well known, with the rise of the automobile industry, rolling precision of rolled steel sheets and the like has become more demanding, and uniformity in the longitudinal direction of the rolling side has almost been achieved. The uniformity in the width direction, that is, the uniformity in the entire width direction of the temporary crown, has reached the level of technology that is completely satisfactory. Various technologies have been developed and researched to deal with this problem.

In addition, it is not necessary to control the temporary crown from a substantially convex to a flat range mainly with regard to the temporary crown correction ability, and it is strongly possible to control the temporary crown from the furan to a concave plate crown. desired.

The technical means for temporary crown control that has been developed so far is mainly to make rolls such as work rolls, intermediate rolls, and reinforcing rolls curved with respect to the entire length of the barrel, and to provide them with axial movement means. This is what is being done.

<Problem to be solved by the invention> For example, in the rolling mill of the invention disclosed in JP-A-56-30014, since a quadratic equation is used for the curve regulating the roll contour of the pair of work rolls, the roll The curve of the initial crown of the profile has only minimum and maximum values, and therefore it is natural that the same roll must be used to obtain the required range of roll gap crown change during mechanically limited relative movement in the barrel direction. For example, when applied to a work roll in a rolling mill with a four-tier structure, contact with the reinforcing roll becomes uneven, resulting in roll marks. However, there are disadvantages such as differences in peripheral speed and slippage, which lowers product quality and reliability of the product.

The contours of the pair of rolls are point symmetrical, and one roll has a convex crown on one side in the axial direction and a concave crown on the other side, so the work roll When the rolled material 2 is rolled by the pair of rolls 1.1', when the rolls move relative to each other in point symmetry in the axial direction, the roll cap crown has a convex shape as shown in FIG.
Although the flat type as shown in the figure and the concave type as shown in Figure 10 have an infinite range of correction functions, in practice there is no need for convex type plate crown control as shown in Figure 8. , No. 9
Since only the plate crown control from the flat type shown in the figure to the concave type shown in Fig. 10 is required, unnecessary convex type or flat type plate crown control is a wasteful disadvantage of having an unnecessary control capability range. there were.

In addition, even if the upper and lower work rolls are moved relative to each other in the axial direction point-symmetrically to use a roll curve using a quadratic equation, the component of the plate crown that can be changed is diamond-shaped, reversed, or diamond-shaped. It is said that only the first-order component related to the distance in the roll axis direction of the mold can be changed, and the necessary second-order component cannot be changed freely due to the characteristics of roll deflection. Actual rolling had some drawbacks.

Furthermore, as shown in the invention disclosed in Japanese Patent Publication No. 51-7635, in a four-high rolling mill, as shown in FIG. Roll 1.1' barrel length is reinforcement roll 3
．． Since the barrel length is equal to 3', the work roll 1 by the reinforcing roll 3.3' is used to control the plate crown.
．． The restraint state for the deflection of 1' is work roll 1.1'
This results in a disturbance state to the roll bending function, which has the drawback of significantly complicating sheet crown control. However, the disadvantage was that the cost was high.

<Object of the Invention> The object of the invention of this application is to provide a structure in which the roll profile of a pair of rolls such as work rolls is curved based on the above-mentioned prior art, which has the advantage of controlling plate crown through roll bending and axial movement. As a technical issue, we aim to solve the problems of extremely large differences in roll diameter, which can cause roll marks and slip marks on products, as well as disturbance conditions being applied to roll bending.
It greatly reduces the diameter difference, makes barrel direction movement unaffected by disturbance conditions even when using roll bending, improves product crystal quality, and allows smooth plate crown control, making it a great addition to the machine manufacturing industry. It is an object of the present invention to provide an excellent roll structure for a rolling mill that is useful in the field of application of C-pull steel plate forming technology.

<Means/effects for solving the problem> In order to solve the above-mentioned problem, the structure of the invention of this application, which is summarized in the above-mentioned claims, is to Tertiary, which smoothly forms maximum and minimum values through inflection points along the entire length of the barrel for any of these roll pairs, including the outer rolls of the intermediate rolls and reinforcing rolls provided above and below, The roll profile is formed using a cubic equation regarding the distance of the roll in the barrel direction, which consists of linear and constant terms, and the roll profile of one of the roll pairs and the roll used is formed point symmetrically, including the parallel movement in the barrel direction, and its By moving the relative position in the axial direction, the plate crown can be adjusted steplessly from a flat type to a concave type, and the roll diameter difference required to achieve the desired roll cap crown change range is greatly reduced, reducing the occurrence of roll marks. In addition, when the pair of rolls such as work rolls are moved in the axial direction and used in combination with roll bending, it is possible to effectively prevent slippage and damage even after the entire barrel length of the pair of rolls has been moved. It is formed so that it extends outward from the end further than the end of the fixed roll pair, so it does not interfere with roll bending and roll movement adjustment, and each function is independent as planned without giving disturbance conditions to roll bending. We have taken technical measures to make this possible.

<Embodiments - Configuration> Next, embodiments of the invention of this application will be described as follows based on FIGS. 1 to 7. Incidentally, parts having the same features as those in FIGS. 8 to 11 will be described using the same reference numerals.

The embodiment shown in FIG. 1 is a four-high rolling mill, in which an upper work roll 1 and a lower work roll 1 are used for rolling material 3.
An upper reinforcing roll 3 and a lower reinforcing roll 3' are provided above and below the reinforcing roll 3 and the lower reinforcing roll 3' as external rolls. It is similar to the machine.

In this embodiment, the roll profile of the roll pair of the upper work roll 1 and the lower work roll 1' is formed into a curved curve based on the cubic equation of the lengthwise distance of the barrel as shown below. For the opposing roll contours of the lower work roll 1', a local maximum point 5.5' and a local minimum point 6 are located, respectively, within its barrel length via an inflection point 4.4'.
．． 6'.

In addition, maximum points, minimum points,
Shadow lines are not displayed to clearly indicate inflection points.

In addition, in this embodiment, the lower reinforcing roll 3 and the lower reinforcing roll 3' are not curved in their roll contours but are formed in a straight shape, and the upper work roll 1 and the lower work roll 1' are different from each other. The roll profile is exaggerated for illustration purposes, and furthermore, the illustrated embodiment is shown with the reduction blade in the unapplied state.

In the case of a two-high rolling mill, the difference in the roll contours of the upper and lower work rolls 1.1' is given as a roll gap crown, but in the four-high rolling mill and the artificial rolling mill, In the embodiment in which a curve of the curved roll profile = 10- line is given to the roll pair of the roll or the intermediate roll, the curved roll profile curve is applied to only one pair of rolls, and the other roll pairs are applied to the straight 1 to flannel. By providing an i~ straight roll profile, twice the amount of plate crown control is provided than in the two-high mill embodiment.

Therefore, the upper and lower work rolls 1 of the four-high rolling mill shown in Fig.
．． Regarding the roll profile of the roll pair 1', the curved shape of the invention of this application will be described in detail with reference to FIGS. 2 to 5.

As shown in FIG. 2, the formula for the lengthwise distance of the barrel in which the roll profile of the pair of rolls is curved is expressed in the barrel direction
If the equation y=ax'+cx+d, which is composed of cubic, linear, and constant terms, is given for the axis y perpendicular to this, it will be as shown in FIG. 2, and will have the following characteristics.

-11= Point that gives the inflection point The roll profile of one of the rolls, which is translated in parallel and has a maximum value of 5 and a minimum value of 6 between the ends 9 and 10, is as shown in FIG. 3, and the neutral point of the barrel is translated by minus W, Maximum value 5' between ends 9' and 10',
The roll profile of the other roll with a body length of 2L having a minimum value of 6' is as shown in Figure 4, and these are schematically arranged with respect to the same axes X and Y so that the neutral point is on the Y axis. When shown, it looks like Figure 5, and in the upper roll, X=X+W
, X-X-W for the lower roll, so the roll contour Y1 of the upper roll and the roll contour Y2 of the lower roll are given by the following formula (1)
, (2), respectively.

Y+ =a (X+w>' 10c (X+w> 10(j
+ (1) Y2 = a (X-W> 3+C(X W
) -1-d2 (2) And as shown in Figure 5,
When Y+ -Y2=11, a'w'+cw+d+-(-avv' -GW-1-
d2)-i.e., 2cw3+ 2cw+d, -62=h (3)
The shape of the roll gap at the neutral position in the barrel axis direction, dY, is 〆Y=Y+ -Y2 -(a (X3+3wX2+ 3w2X+w') 10 (X10w) 10d+) - (a (x3-3wX2 + 3w2 -w3
) 100 (X W>+d2) -6aw×2+2aw' + 2cw 10dl-d2 -6cwX2 +h (4
) Next, as shown in Fig. 6, move the upper roll 1 and the lower roll 1' of the work roll from the neutral position shown in Fig. 5 to the right direction v1 and the left direction equidistantly to V. When it moves (this is called parallel movement on the defrozen side), the roll contour is Y+' = a ((X-V) +W) '10G ((
X V> +W) 10d+ (1')Y2'
=a ((X1V) -W) '10G ((X1V) -W
) +d2 (2') Then, the shape of the roll cap, dY', after being symmetrically moved in parallel to the defrozen side in the axial direction is dY' - Y+ 'Yz' -a (X+(w-v)) 3 10 (X±(W-V)) 10d+ -a (X-(W-V)) ' 10c (X-iw-v))+d2 -6a (w-v) X2+2a (w-v) '+2
c(w-) 10d, -d,.

-6a (w-v) It turns out that you can get something.

In the case of parallel movement symmetrically in the axial direction in the opposite direction (this is called parallel movement on the increase side), the above formula (5)
By substituting (-■) into .

When parallel movement is performed to the defroze side and when parallel movement is performed to the increase side, if the plate width is 2B and the parallel movement is deviated from iv-±V, the plate crown change range γ is as follows.

In the case of parallel movement on the defrozen side, V-10V, X=
Roll gap at B: α1v-10V, roll cap at X=O: plate crown at α2v-10y
: If we put △α, then △(X-(Xz (Xl--68CW-V)82
(6) Similarly, in the case of parallel movement on the increase side, v−−V, roll gap at x=B: β1■−1■,
Roll gap at x=O: Plate crown at β2v=-V: △β△β-β2-β1--68 (w
10v>82 (7) Therefore, the plate crown change range γ is expressed as γ=Δα−Δβ−12aVB2 (8).

From the above, the plate crown change range γ of the rolled material 2 is determined by the equation regarding the limit value V of the amount of axial movement from the axial neutral position of the roll to the left and right, the plate width 2B, and the distance in the barrel direction of the curve of the roll profile. It is determined by the coefficient a of the third-order term, and is completely unrelated to the coefficient G of the first-order term and the constants d1, d2, or the parallel movement amount W of the neutral point.

Here, it is known that the roll caps of the work roll, reinforcing roll, and intermediate roll are generally subjected to rolling reaction force and have a convex distribution of roll caps, and the main component in the formula is the longitudinal direction of the barrel. It is known that it is a quadratic term of distance.

On the other hand, from the above equations (4) and (5), if the upper work roll 1 is moved in parallel from the defroze side to the increase side, that is, from right to left, symmetrically It can be seen that when the roll 1' is translated in parallel from left to right, the roll cap distribution changes arbitrarily from the convex shape shown in FIG. 8 to the concave shape shown in FIG. 10 depending on the coefficient of the second-order term in the equation.

Therefore, the correction of the convex roll cap, which changes according to the E-coal deflection that changes depending on the cross-section conditions, can be made accurately by at least controlling the flat shape shown in Figure 9 to the concave shape shown in Figure 10. This shows that corrections can be made.

Therefore, it is desirable to obtain a concave roll gap as large as possible, but from this point of view, the maximum shape control ability can be obtained by taking the axial movement amount of w = V from equation (6). Koto Nekaru.

In addition, when using a roll that is curved over the entire length of the roll barrel, changes in the peripheral surface speed of the roll occur depending on changes in the roll diameter, and this also causes differences in the lubrication conditions between the rolled material and the roll. It was concluded that this would result in a difference in surface roughness and surface gloss on one side of the rolled material, significantly degrading the product properties.Furthermore, the upper and lower rolls are in a positional relationship that interpolates with each other. Therefore, if the change in roll diameter is large, the rolling speed will change on the upper and lower surfaces of the rolled material, causing upsliding and undersliding, and this also reduces confidence in the crystal quality of the product.

Therefore, it is necessary to minimize the diameter difference of the curved roll contour, but in the invention of this application, the first-order coefficient in the cubic equation is set so that both the maximum and minimum values of the curve of the roll contour are within the roll barrel. The previous formula (
It is clear from 8).

Therefore, in order to obtain the required temporary crown change range T, the difference in roll diameter can be reduced between the case where the conventional roll contour curve is used and the case where the roll contour curve according to the invention of this application is used. Let's verify this using concrete numbers.

In the embodiment shown in FIG. 1, the lengths of the barrels 1.1' of the upper and lower work rolls are both 2100 mm, and the horizontal translation ff1V is 100 mm. , board width B is 2000m,
When the required plate crown change range γ is 1 mm, for example, according to the means of the conventional aspect of the invention described in JP-A-56-30014, the upper work roll has y on one side in the axial direction.
1=a+X2+d, convex crown, y2 on the opposite side
A concave crown profile of -a2X2+d2 is provided, and the initial crown of the lower work roll has approximately the same shape and is symmetrical with respect to a point.

In the following discussion, symbols will be used as equations (1) to (8)! If it is $, then Y+ = a+ (X+W) 2+d,
(1')Y2 =82 (X W) 2+d2
(2”) x=0: Y+ −Y2 =hcl;
(at-al)W2+d+ -d2 =h (3
')△Y=Y+ -Y2 -(at 82)X2 12 (at W+82W)x10h (4')Y+
' -8+ ((X-V) +W) 2+d+ (1
” )Y2'-82((X1V)-W)2+d2 (
2') △Y' - (at az ) x' + 2 (a1 + az ) (w-v)
α1 = (at −82)82 −2(at +820w V)B (6″′)8β
-β2-β1 = (at -82)82 -2(at +82) (w10V)B (7')T-
△α−△β−4 (at +82) VB (8'
) Substitute T-1mm, -ioo,, B=1000mm Sult, = 21 - For simplicity, considering the case where the amount of movement of the neutral point W=O, the contour of the right half of the upper roll Y+ R=a+ X2+d.

Outline of the left half of the upper roll YI L - a2X2+d.

Therefore, YlR-a1L2+d1 at the right body end of the upper roll, and Y+ L --az L2+d at the left body end of the upper roll.

Since L=1100m, the roll diameter difference is 2X
(at +82) L” is required.

Also, the drawbacks of this prior art are the equation (4M) and (41)
It can be clearly read in the formula.

In other words, the coefficient of the quadratic term of It can be seen that only the coefficients of the first-order terms of a I, t x can be changed, and that only diamond-shaped or inverse diamond-shaped plate crown control can be performed.

If the above process is applied, for example, to a work roll having a roll profile proportional to the cubic term of the applicant's earlier patent application No. 103941/1983, if the roll curve y=ax3+dXw=o , upper roll contour Yl-aX3+d.

= 23- = 1.109+d+ () Deep) −-1,109+d+ <mm> Roll diameter difference 1.109X 2X 2= 4.436#1
I11 On the other hand, when the means of the invention of this application is applied, the roll curve y=aX3+cx+d.

w=V (= 100) The point that gives the extreme value, as shown in X-+50(), is the coefficient 1-- 0.6900
+d+X--1100 'y', -10.
2083 +d+x=500, that is, when X=400, Y+ = -0,2083+d+ 2
-1.7966 mm Specific examples of the above-mentioned conventional aspects and the aspect of the invention of this application are summarized in Table 1, and the roll diameter giving the roll gap crown change range of the invention of this application. It was found that the difference was significantly reduced, and as a result, it was clearly seen that it was effective in preventing the occurrence of roll marks and slip scratches.

Table 1 Next, in the embodiment shown in FIG. 7, the upper intermediate roll 11 and the lower intermediate roll 11' of the artificial rolling mill have cubic, linear, and constant terms, as in the above-mentioned four-high rolling mill. This is an embodiment in which a roll profile of the formula % is provided, and in this example as well, the maximum value and the minimum value exist within the entire length of the barrel.

Furthermore, the effects of the embodiment shown in FIG. 7 are the same as those of the embodiment shown in FIG.
it is obvious.

In this embodiment, the work roll 1.1' and the reinforcing roll 3.3' are formed into flat straight rolls.

In addition, in the embodiment shown in FIG. 1.7, when the pair of rolls having the cubic roll profile described above is shifted in parallel to the barrel direction, the opposite ends 9.1(), 9'
, 10' is formed with a long barrel length that covers the fixed rolls even after the axial movement of the pair of flat straight rolls. When the axially fixed roll and the axially moving roll change or do not change, the restraining state of the deflection of both rolls changes, and by adjusting the barrel direction movement of the axially moving roll. It can be seen that no disturbance effect is applied to the roll bending effect, and there is no effect on the plate crown control by roll bending.

It goes without saying that the embodiments of the invention of this application are not limited to the above-mentioned embodiments; for example, they can be applied to rolling mills with a width larger than one stride, Various aspects can be adopted, such as application.

<Effects of the Invention> As described above, according to the invention of this application, a cubic roll profile having a maximum value and a minimum value between the roll barrels is provided to at least one of the roll pairs of a rolling mill. As a result, the roll diameter difference in the roll contour that gives the crown change range of the work roll gap is significantly reduced, the peripheral speed change of the rolls is also small, the contact between the contacting rolls is not uneven, and roll marks and slip scratches are not caused. First, it is determined whether the product has an excellent effect on improving the reliability of the product or not.

In addition, since the convex roll gap for the sheet crown, which changes in response to changes in rolling conditions, can be corrected in a manner that adapts to the actual rolling conditions, and can range from flat to concave,
An excellent effect is achieved in that inconveniences such as 1/4 part elongation do not occur, and unnecessary plate crown shape control ability is not provided.

Moreover, even though a roll having a curved roll profile is used over the entire length of the roll barrel, there is little change in the roll peripheral speed, and even when the present invention is applied to a work roll, the distance between the rolled material and the roll is small. There is no unevenness in the lubrication conditions,
There is no unevenness in surface roughness or surface gloss on one side of the rolled material, and from this point of view as well, an excellent effect is achieved in that product precision can be significantly improved.

Furthermore, as mentioned above, even though the upper and lower rolls interpolate with each other, the difference in the roll diameters is small, so even when the invention of this application is applied to work rolls, the upper and lower rolls interpolate with each other due to changes in peripheral speed. No sagging or sagging is formed, which also has an excellent effect of improving the reliability of the product.

Furthermore, even if roll pending is used in combination with the upper and lower rolls being moved in the axial direction, both ends of the moving rolls will be located further outside of both ends of the fixed rolls, and therefore the reinforcing rolls and work rolls will be Since there is no change in the contact state and there is no unevenness in the constraint state of roll deflection, the roll bending effect for plate crown control, which causes disturbance conditions to be given to the roll bending effect, is applied as designed. This is an excellent effect.

[Brief explanation of the drawing]

1 to 7 are detailed explanatory diagrams of the invention of this application, in which FIG. 1 is a schematic front view of one embodiment, FIG. 2 is a graph of a basic cubic curve that provides a roll profile, and FIG. Figure 3 is a graph showing how the upper roll of the roll is given a roll contour, Figure 4 is a graph showing how the roll outline is given to the lower roll of the roll, Figure 5 is a schematic front view of the roll pair, and Figure 6 is a graph showing how the upper roll and the roll outline are given. A graph showing the lower rolls moved in parallel, Fig. 7 is a schematic front view of an embodiment equivalent to Fig. 1, Fig. 8 is a schematic front view of convex control of the plate crown, and Fig. 9 is a flat plate crown. =30=Schematic front view of control, FIG. 10 is a schematic front view of concave plate crown control, and FIG. 11 is a schematic front view of plate crown control based on the prior art. 1.1'...Work roll, 3.3'...External roll, 4.4'...Inflection point, 5.5'...Local maximum value, 6.6'...Local minimum value

Claims (2)

[Claims] (1) In the roll structure of a rolling mill in which external rolls are provided above and below a pair of work rolls, and one of these roll pairs has a curved roll profile over the entire length of the barrel, the roll profile of the roll pair is curved. A cubic equation regarding the distance in the roll axis direction, which is composed of cubic, linear, and constant terms, and consists of parts having maximum and minimum values, such that the roll contours of one and the other of the roll pair are parallel to each other in the barrel length direction. A roll structure of a rolling mill characterized by being formed point-symmetrically including movement. (2) In the roll structure of a rolling mill in which external rolls are provided above and below a pair of work rolls, and one of these roll pairs has a curved roll profile over the entire length of the barrel, the roll profile of the roll pair is curved. A cubic equation regarding the distance in the roll axis direction, which is composed of cubic, linear, and constant terms, and consists of parts having maximum and minimum values, such that the roll contours of one and the other of the roll pair are parallel to each other in the barrel length direction. The pair of rolls is formed to be point symmetrical including movement, and furthermore, the pair of rolls is movable in the axial direction with respect to the fixed roll in the axial direction, so that the entire length of the pair of moving rolls is longer than that of the fixed roll in the axial direction even after the end portion is moved. The roll structure of a rolling mill is characterized by being long outward.