JPH05220509A - Arithmetic device for rolling schedule - Google Patents

Abstract

PURPOSE:To calculate the loss of power in a rolling mill system that is used at the time of setting rolling schedule with high accuracy. CONSTITUTION:In the case of calculation of the loss Lossi of power, test run of each rolling stand is plural times executed in the state of kiss-roll and data are collected to determine unknown coefficients C1i, C2i, C3i, in a prescribed operation expression including rolling force PRi and roll speed Vri. The values of C1i, C2i, C3i are determined by executing regression analysis of these data. After Ci, C2i, C3i are determined like this, the loss Lossi of power under a certain condition is calculated with a means 2 for calculating the loss of power by substituting desired values for PRi and VRi in the prescribed operation expression.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling schedule calculation device used when setting a rolling schedule for a material to be rolled such as a metal material.

[0002]

2. Description of the Related Art When rolling a material to be rolled, a rolling mill system is controlled by a calculation control device using an electronic calculator. In addition, when setting the rolling schedule, various information such as information about the material to be rolled, information about the rolling mill, information about the rolling method and its operation, and the like are input to the rolling schedule calculation device in the calculation control device. And
By using various rolling models, the setting values of the roll opening and the roll speed of the rolling mill are calculated according to a predetermined algorithm.

In the process of setting the rolling schedule, the calculation of the power of the rolling mill drive motor together with the rolling load occupies an important position. In determining the required power of this rolling mill drive motor, the rolling power that contributes to rolling (also called "pure rolling power". For its calculation method, see, for example, "Theory and Practice of Sheet Rolling" edited by the Iron and Steel Institute of Japan. (Published in 1984)), it is necessary to consider the power loss generated in the rolling mill system including the electric motor. In conventional setting calculations, this power loss is usually given as a constant, or
It was given as a certain percentage of rolling power.

[0004]

However, as the power loss during operation of the rolling mill system, there are losses in bearings, losses due to contact between rolls, losses in transmissions, losses in shaft couplings, etc. However, it is difficult to specify them separately, and it is difficult to theoretically formulate them. It is said that this power loss may exceed 10% of the effective rolling power during normal rolling. Therefore, the error in the evaluation of power loss is due to the accuracy of rolling schedule setting.
There was a possibility that it would have a direct and significant impact.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a rolling schedule calculation device capable of predicting power loss of a rolling mill system with high accuracy when setting a rolling schedule. I am trying.

[0006]

As a means for solving the above-mentioned problems, the present invention is a rolling schedule calculation device for calculating a rolling schedule of a material to be rolled in consideration of a power loss of a rolling mill system. In, in order to provide a power loss calculation means for calculating the power loss by a predetermined calculation formula using the rolling load, roll speed, and a predetermined coefficient,
Moreover, the predetermined coefficient is obtained by performing a trial operation of the rolling mill system in advance without rolling the material to be rolled.

[0007]

In the above structure, first, the values of the rolling load and the roll speed are determined, and the rolling mill driving motor is given a constant pressure to operate the rolling mill on a trial basis.
Since the operation in this case is performed without flowing the material to be rolled into the rolling path, it can be easily performed.

After performing such a test operation a plurality of times under different conditions, the measurement results are analyzed by a mathematical method.
Thus, it is possible to determine the value of the unknown predetermined coefficient in the power loss calculation formula, and to calculate the predetermined calculation formula. The power loss given by this predetermined calculation formula is extremely accurate because it is obtained based on the trial run of the rolling mill system to actually perform rolling.

[0009]

Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 is a block diagram showing the configuration of a rolling schedule calculation device provided in the calculation control device.

The rolling schedule calculation device 1 is provided with input information such as the plate thickness of the material to be rolled, processing time, etc., and based on these input information, output information such as rolling load, roll opening, roll speed, etc. is omitted. Is output to the rolling control device. This rolling schedule calculation device 1 is
The power loss calculating means 2 is provided inside, and the power loss Loss output from the power loss calculating means 2 is used to calculate the rolling schedule setting.

Next, the process until the power loss calculating means 2 outputs the power loss Loss will be described. In addition,
The rolling mill according to this embodiment is a five-stand cold tandem rolling mill in which five stands are arranged on the rolling path.

In this embodiment, the power loss of a certain stand is first modeled by the following equation (1).

[0013]

[Equation 1] Here, in the formula (1), Lossi is the power loss (KW) of the i-th stand, P _Ri is the rolling load (KN), V _Ri is the roll speed (m / min), C _1i , C _2i and C _3i. (C _2i and C _3i are exponents) indicate constants depending on the stand.

Then, the coefficients C _1i , C _2i and C _{3i of the} equation (1) are
Is determined as follows. First, each stand is operated in an unloaded state (so-called kiss roll state), the roll speed is changed stepwise while the rolling load (roll contact load) is kept constant, and the motor input at each speed at that time is changed. To measure. Next, this time, the rolling load is changed while keeping the roll speed constant, and the electric motor input at each load at that time is measured. The number of measurements in this case is
The roll speed may be about 5 to 8 steps, and the rolling load may be about 4 to 6 steps. By regression analysis of the measurement result, the coefficients C _1i , C _2i and C _3i in the equation (1) can be obtained.

In this way, if the values of the coefficients C _1i , C _2i and C _3i in each stand are given, this time, the desired values of P _Ri and V _Ri are _added to the equation (1) using these values. By substituting, the power loss Lossi of each stand can be obtained. Since the value of the power loss Lossi is obtained based on the trial run of the stand to be actually used from now on, the value is very accurate. Further, since this trial operation is performed without actually rolling the material to be rolled, it can be easily performed.

The table of FIG. 2 shows specific numerical values of the coefficients C _1i , C _2i and C _3i at each stand obtained from the results of the above regression analysis. R in the table is a multiple correlation coefficient representing the reliability of the calculated value shown in this table with respect to the actual measurement value. As indicated by the value of R, the coefficients C _1i , C _2i , C _3i
The value of is very reliable. Therefore, the power loss Lossi calculated by the power loss calculating means 2 using these coefficients is also highly accurate. Specifically, the accuracy could be improved by about 20 to 30% over the power loss calculated by the conventional method.

FIG. 3 is a characteristic diagram showing the relationship between the roll speed change and the power loss in each stand, which is created using the power loss Losssi calculated in this way.

Since the rolling schedule calculation device 1 performs calculation based on such a highly accurate power loss Lossi, the rolling schedule setting accuracy can be improved. Therefore, the quality of the material to be rolled can be improved and the operation can be stabilized. In addition,
An example of calculation in the case of setting a rolling schedule in consideration of power loss is disclosed in Japanese Patent Publication No. 56-17964.

[0019]

As described above, according to the present invention, the predetermined coefficient is obtained by performing the trial run of the rolling mill system in advance, and the predetermined coefficient and the predetermined rolling load and roll speed are used. Since the power loss is calculated by the calculation formula, it is possible to obtain a power loss of the rolling mill system at the time of setting the rolling schedule that is much more accurate than the conventional one, though it has a simple configuration. ..

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a rolling schedule calculation device according to an embodiment of the present invention.

FIG. 2 is a table showing values of a predetermined coefficient for each stand used by the power loss calculating means of FIG.

FIG. 3 is a characteristic diagram of power loss obtained by the power loss calculating means of FIG.

[Explanation of symbols]

1 Rolling Schedule Calculator 2 Power Loss Calculator Lossi Power Loss P _Ri Rolling Load V _Ri Roll Speed C _1i , C _2i , C _3i Predetermined Coefficient

Claims (1)

[Claims] 1. A rolling schedule calculation device for calculating a rolling schedule of a material to be rolled in consideration of a power loss in a rolling mill system, a predetermined calculation formula using a rolling load, a roll speed, and a predetermined coefficient. Therefore, a power loss calculating means for calculating the power loss is provided, and the predetermined coefficient is obtained by performing a trial run of the rolling mill system in advance without rolling the material to be rolled. A rolling schedule calculation device characterized by the above.