JPS62221709A - Computer-controlled plate thickness controller - Google Patents

Abstract

PURPOSE:To attain the satisfactory accuracy of plate thickness by obtaining the relation among the rolling reduction, the forward slip and the backward slip in the form of a simple approximate equation based on the result value and then solving said approximate equation by means of the actual rolling reduction obtained in a rolling state after start of the rolling. CONSTITUTION:The roll gap, the mill speed and the present result values (a) of the input/output side speeds of a rolled stock are collected from each mill stand under rolling by a result value collector 4. Then an arithmetic circuit 3 calculates the rolling reduction, the forward slip and the backward slip (b) of the rolling stock under rolling and writes them to a memory 1. When a rolling schedule (e) of the material to be rolled is supplied, a memory control circuit 2 reads the corresponding data (d) out of the memory 1. Then the circuit 3 calculates a simple approximate equation (f) of both forward and backward slip relating to the rolling reduction based on the read-out data. A control part 6 solves the given simple approximate equation based on the actual rolling reduction calculated then by the circuit 3 in a rolling mode and uses those obtained forward and backward slip for compensation of acceleration/ deceleration of a pay-off reel, a tension reel, etc., as the optimum values respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a computer-controlled plate thickness control device for a plate rolling mill.

[Conventional technology]

The values of the leading rate and backward rate in the rolling process of plate materials have important meaning for their control, whether rolling is performed by a one-stand rolling mill or unwinding by a payoff reel, tension reel, coiler, etc. It is data. Furthermore, in the case of tandem rolling, the importance of Φ increases. In other words, in order to achieve smooth rolling, the flow of material passing through each stand must be constant at any part of the rolled material during tandem rolling. If there is too much or too little material, loops will form between the stands, or the tension between the stands will increase.

1. Therefore, the conventional ;t'f: J machine side (ilI plate thickness control device also performs control by setting forward = i? and reverse rate.

[Problem that the invention seeks to solve]

The conventional il'Q aircraft side plate thickness control neck described above considers the advanced rate to be a fixed ratio to the downstream rate. For example, empirically, the downstream rate of about 115 is considered to be the advanced rate. It is used to compensate for the acceleration and deceleration of each mill motor, but there is no consideration based on actual values, and there is no stratification based on rolled material or rolls used, so it lacks accuracy and is used to compensate for the viscosity of plate thickness. It has the disadvantage that it cannot forcefully reach I+ within 11 minutes.

[Means for Solving the Problems] The;+p machine control board thickness control device of the present invention is characterized by
”: Corresponds to the specifications and the rolling reduction rate and rolling rate of the mill stand %. A, associate-(i, later ill JA record value is written + f A memory control means for reading out data corresponding to the set material specifications from the data in the middle when the material specifications are increased by one step; A performance value collection stage that collects the speed I store, exit speed +a, mill speed, roll gap performance (+/i), and AI calculation of pressure 1.1, advance rate, and reverse rate based on the performance values. In addition, based on actual data manually entered from memory before rolling, a linear approximation formula is calculated that indicates the relationship between the downstream rate, the leading rate, and the backward rate applied to the rolled material to be rolled. Using the approximation formula, calculate the forwarding rate and backward rate corresponding to the working dos' and the result value of the rolling 44 during rolling.
Table 1\17 shows the first stage of control output as Jl141, the data 31 in the memory, and the calculated - order approximation formula.
, and has a large/small setting-L stage that allows the setting of the calculated linear approximation equation to be changed 11 times.

[Effect]

In this way, the forwarding rate and backward rate corresponding to the rolling reduction rate, which are Vt+ based on the past rolling actual values for each material, material dimension specification, and stand, are always kept updated and kept. Once the original is determined, a first-order approximation formula is created to calculate the forwarding rate and backward rate corresponding to the rolling reduction rate from these stored data, and this approximate formula is used during rolling to improve the rolling rate. The optimum advance rate and backward rate corresponding to the actual rolling reduction rate of the material can be determined and used for acceleration/deceleration compensation of payoff reels, tension reels, etc.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

Fig. 1 is a block diagram showing an embodiment of the computer-controlled plate thickness control device of the present invention applied to a 4-high tandem cold mill consisting of N stands, and Fig. 2 is a CRT display setting device 7.
This is a graph corresponding to an example of advanced rate data plotted in , and a linear approximation formula calculated from these data.

The coil to be rolled is unwound from a payoff reel 8, rolled on a flat 1 mil stand 9 to a 1 mil stand 10, and then wound onto a tension reel 11.

A large-capacity memory 1 stores actual values such as the rolling reduction rate and the corresponding advance rate and backward movement (l) for each material, material dimensions, and mill stand of the rolled material. The actual value collection device 4 collects the roll gap set during rolling measured by the mill sensor, the input speed and exit speed of the rolled material, and outputs it to the arithmetic circuit 3. The clock 5 outputs the operation timing of the actual value collection device 4.The arithmetic circuit 3 calculates the downstream rate and the corresponding advanced rate and backward rate based on the data input from the actual value collection device 4. Calculate and also
A first-order approximation formula showing the relationship between the downstream rate, the leading rate, and the backward rate is calculated from the past performance values of these data manually entered from the memory 1 during rolling preparation. The control unit 6 uses the current rolling ratio inputted during rolling to determine the advanced ratio, based on the linear approximation formula,
Calculate the porosity. The CR7 display setting device 7 displays the data read out from the memory 1 and the graph of the computed linear approximation equation, and also allows the operator to set - in the arithmetic circuit 3.
- It is possible to change and set the next approximation formula.

Next, the operation of this embodiment will be explained according to the processing procedure.

(1) The actual value collection device 4 collects the current actual values a of the roll gap, mill speed, and input and exit speeds of the rolled material from each mill stand during rolling. The timing of collection is based on the clock 5, but generally data is collected at fixed time intervals after the start of rolling.

(2) Using this actual value, the arithmetic circuit 3 calculates the rolling rate, advance rate, and reverse rate of the rolled material during rolling.

(3) The memory control circuit 2 writes these data C into the corresponding area of the memory 1 for each material, material dimensions, and stand.

The following 1- is the processing related to collection of performance values and storage of them by stratification. Next, (4) When the rolling schedule e of the material to be rolled is input, the memory control circuit 2 reads the corresponding data d in the memory l.

(5) The arithmetic circuit 3 uses the read data to calculate a linear approximation formula f for the advance rate and backward rate for the rolling reduction rate.

(8) The CR7 display setting device 7 allows the operator to display and check each data d scatter diagram and the next approximation formula f before rolling, and when necessary, the first approximation formula f by the setting change signal g. It is also possible to modify.

(7) The first-order approximation formula f held by the arithmetic circuit 3 is passed to the control unit 6.

With the above steps, preparations before starting rolling are completed. When rolling is started, (8) the control unit 6 solves the given linear approximation equation using the actual downstream rate calculated by the arithmetic circuit 3 during rolling, and calculates the leading rate and backward rate. The optimum value is used for acceleration/deceleration compensation of payoff reels, tension reels, etc.

Therefore, the mill stand motor control device can always perform acceleration/deceleration compensation control using the advance rate and reverse rate based on past results as optimal values corresponding to the actual rolling reduction rate.

〔Effect of the invention〕

As explained above, the present invention includes a memory, a memory control means, an actual value collection means, a calculation means, a control means, and a display setting means to determine the stand entry and exit speeds of rolled material. Collect the actual values of the roll gap and mill speed at the time, and calculate the advance rate for the rolling reduction rate by processing this.
Calculate the backward movement rate and use these data as material, material dimensions,
and stratified by each stand and stored in the memory, and when the rolling schedule is decided before rolling, the corresponding data is taken out from the memory and based on these actual values,
The relationship between the rolling reduction ratio, advancing ratio, and retreating ratio is determined as a first-order approximation formula, and after the start of rolling, this first-order approximation formula is solved using the actual reduction ratio during rolling. Since it is possible to set the advance rate and reverse rate as the optimal values corresponding to the actual rolling reduction rate based on the actual values, the optimal acceleration/deceleration compensation control for payoff reels, tension reels, etc. using these values is It has the effect of greatly contributing to the important quality of rolled materials, which is plate thickness.
Furthermore, by continuously collecting results, it is possible to compensate for changes in rigidity caused by roll replacement, aging of the rolling mill itself, etc.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the computer-controlled sheet thickness control device of the present invention applied to an N-stand 4-high tandem cold mill, and FIG. It is a graph corresponding to an example of rate data and a linear approximation formula calculated from these actual values. DESCRIPTION OF SYMBOLS 1...Memory, 2...Memory control circuit, 3...Arithmetic circuit, 4...Actual value collection device, 5...Clock, 6...Control unit, 7...
...CRT display setting device, 8...Payoff reel, 9...Mountain mill stand, 10...4N mill stand, 11...Tension reel, a-g...Data signal. Patent applicant Yaskawa Electric Co., Ltd. Agent
Tadashi Wakabayashi Figure 1

Claims (1)

[Scope of Claims] A computer-controlled plate thickness control device for a plate rolling mill, which stores material, material dimensions, rolling reduction rate for each mill stand, and actual values of advancing rate and backward rate corresponding to the rolling rate. Memory: During rolling, the reduction rate of the rolled material and the corresponding forwarding rate and backward rate are written to the memory, and when the material specifications are set before rolling, the set material specifications are updated from the data in the memory. a memory control means for reading corresponding data; a performance value collection means for collecting performance values of the input speed, exit speed, mill speed, and roll gap of the rolled material for each stand during rolling; Calculate the rolling reduction rate, leading rate, and backward rate based on the values, and calculate the relationship between the rolling rate, leading rate, and backward rate applied to the rolled material to be rolled based on the actual data input from the memory before rolling. a calculation means for calculating a first-order approximation formula showing a relationship; a control means for calculating an advance rate and a backward rate corresponding to the actual reduction rate value of the rolled material during rolling using the first-order approximation formula, and outputting the results as a control signal; A computer-controlled plate thickness control device comprising a display setting means that displays data in a memory and a calculated linear approximation equation, and can change settings of the calculated linear approximation equation.