JPS62248504A - Method for determining shift position of work roll shift rolling mill - Google Patents

Abstract

PURPOSE:To improve the shape of a broad rolling material and to permit the execution of cross erturn rolling by determining a shift position in such a manner that the final wear shape of a roll is approximated as far as possible to a quadratic curve based on a given rolling schedule. CONSTITUTION:The quadratic curve assumed with the final wear position of a roll center as P is obtd. in accordance with the rolling schedule (data such as number of rolling materials, the width, thickness, material quality, etc., of the respective rolling materials). The points Q, Q' where wear loss=0 is determined with the quadratic curve. The positon where the quadratic curve obtd. in such a manner and the broadest rolling material 1 among the rolling materials contact at the upper right vertex is determined as the shift position in rolling of the sheet material 1. The rolling material 2 having the next largest width is made to contact the quadratic curve at the upper left vertex and such position is determined as the shift position of the sheet material 2. The roll wear is realized as the quadratic curve and the rolling with high reliability is executed by the above-mentioned method.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a shift position determining method applied to shape control of work rolls of a work roll shift rolling mill.

<Conventional technology> The working roll shift rolling mill is shown in Fig. 3.

1 is a work roll, 2 is a rolled material, and 3 is a backup roll.The rolling mill uses a work roll shift mechanism to adjust the work roll center position (double-dashed line in Fig. 3) and the plate center position fl.
(dotted chain line in FIG. 3) is shifted to distribute the wear of the work roll. Fig. 4 shows an example of a shift pattern when several tens of rolled materials of the same width are continuously rolled. In Fig. 4, S and ax are the maximum values of the shift amount,
-S ma! indicate the minimum value of the shift amount.

<Problems to be Solved by the Invention> However, when this method is applied to a rolling schedule in which the strip width changes during rolling, the following problems occur. For example, as shown in FIG. 5, consider a rolling schedule in which the first 5 trees are wide and the following 5 trees are narrow (numerals in the figure indicate the rolling order).

It is assumed that the wear amount of each rolled material is uniform in the width direction. When the shift pattern shown in Figure 4 is applied to this rolling schedule, the roll wear distribution is asymmetrical as shown in Figure 6, and when changing from wide to narrow, a wear step occurs on the left side ( Here, the dashed line indicates the center of the roll).

In response to such a wear profile, if an attempt is made to roll a rolled material having a width wider than the worn part, the shape will become defective, and width return rolling is virtually impossible, which poses a problem.

Means for Solving the Problems> In order to solve the above problems, the configuration of the present invention is based on a rolling schedule given in advance (data such as number of rolls, width, thickness, material, etc. of each rolled material). Based on the amount of wear at the center of the roll and the total amount of roll wear due to all rolled materials, the area surrounded by the straight line of the wear amount O on the quadratic curve with the wear amount at the center of the roll as the apex is the total area. The feature is that a target wear curve is defined that matches the amount of roll wear, and the shift position is determined so that the amount of roll wear matches this curve.

Effects> With the above configuration, the roll wear shape can be realized symmetrically and as a quadratic curve.

Example: Assume that the plate width of the rolled material and the amount of wear when rolling each rolled material are given as shown in Fig. 5. In a normal one-work roll shift rolling mill, the center of the roll always hits the plate. Therefore, in this example, a quadratic curve with the final wear position at the center of the roll as point P is assumed, and a point where the area surrounded by this quadratic curve and the line with a wear amount of 0 coincides with the total roll wear amount is determined. Find Q and Q' (see Figure 1).

Next, for the rolled material with the widest plate width, find the shift position so that the upper right apex touches the quadratic curve as shown in the rolled material Φ in Figure 2.0 For the rolled material with the widest plate width ■, find the shift position Set the shift position so that the vertex touches the quadratic curve. in this way,
Find the shift position by making the left and right vertices alternately touch the quadratic curve, starting from the one with the widest board width. The results are shown in FIG. 2, and it can be seen that they almost match the target secondary wear curve Q P Q'.

<Effects of the Invention> As described above, according to the present invention, the roll wear profile is obtained as a quadratic curve, so that one-width return rolling is possible.

[Brief explanation of drawings]

Fig. 1 is a principle diagram showing the procedure for realizing the present invention, Fig. 2 is a principle diagram showing the procedure of the present invention for the rolling schedule of Fig. 5, and Fig. 3 is a mechanical concept of a work roll shift rolling mill. Figure 4 is a principle diagram showing an example of a conventional shift procedure, Figure 5 is a principle diagram showing the rolling schedule and the amount of roll wear due to each rolled material, and Figure 6 is based on the rolling schedule shown in Figure 5. 5 is a principle diagram of the result of applying the shift procedure of FIG. 4. FIG. Also, in the symbols in the figure, 1 is a work roll, 2 is a rolled material, and 3 is a work roll.
It's back to back. Figure 1 Rolling schedule Figure 2 Figure I 33 Figure 4

Claims (1)

[Claims] In a work roll shift rolling mill that shifts the center position of the work roll from the center position of the rolled material in the width direction, input the given rolling schedule and make the final worn shape of the roll as close to a quadratic curve as possible. A method for determining a shift position in a work roll shift rolling mill, characterized in that the shift position is determined as follows.