JPS60223607A - Method for controlling roll gap of rolling mill - Google Patents

Abstract

PURPOSE:To improve the accuracy of a sheet thickness near the front end of a rolling material and to obtain a product having a high yield by setting a roll gap at a small value by a correction rate signal prior to biting to a rolling mill and returning gradually the same to a prescribed roll gap after biting. CONSTITUTION:The value to be set until the rolling material bites into the rolling mill is set at a roll gap setter 1. A subtractor 16 subtracts the correction rate alpha from an arithmetic circuit 14 for the correction rate of the roll gap to be calculated by the material, temp., sheet thickness, etc. of the rolling material from the set value RS of the roll gap from the setter 1. The subtractor applies the subtracted value RS-alpha as the corrected set value of the roll gap to an arithmetic circuit 4 via an adder 17. The roll gap of the rolling mill is thereby set smaller by the correction rate alpha than the roll gap under rolling. The correction signal of the roll gap is thereafter so generated that the prescribed roll gap is maintained since the succeeding material is bitten into the rolling mill until the material is bitten in the succeeding rolling mill.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a roll opening control device for a rolling mill.

[Prior art]

FIG. 3 is a block diagram showing an example of a conventional rolling mill roll opening degree control device. In this figure, (1) is a setting device that sets the opening of the rolling mill roll (9), (2) is a pulse transmitter that detects the roll opening, and the electric motor ( 8). (3)
is a position detection counter which inputs the signal from the pulse transmitter (2) and outputs a signal indicating the degree of opening of the bladder. (
4) is an arithmetic unit that inputs the setting signal from the setting device (1) and the roll opening signal from the position detection counter (3), and calculates the difference between them. A slowdown profile generator that generates a signal to the control system that sets the roll opening degree from the deviation signal, (6) is a DIA converter, and (7) is driven by an analog signal from the DIA converter (6). It is a thyristor device.

FIG. 4 is a schematic diagram of the configuration of a continuous hot rolling mill.

Here, a case is shown in which the rolling mills (91) - (9z), . In such a continuous hot rolling machine, the roll opening degree is set at the tail end of the previous material.

When passing through each rolling mill, setting for the next material begins.

In the device shown in Fig. 6, the roll opening degree setting for the next material is as follows:
It is set in the roll opening setting device (1). The calculator (4) calculates the deviation between the roll opening set value and the signal indicating the roll opening from the position detection counter (3), and the slowdown profile generator generates a control signal in response to this deviation. This is output to the thyristor device via the DIA converter (6). The drive of the electric motor (8) is controlled by a thyristor device (7), and the roll opening degree of the rolling mill roll (9) is moved to a set value.

FIG. 5 is a waveform chart showing the setting of the roll opening degree in the device shown in FIG. 6 over time. When removing the tail end of the previous material, the roll opening degree is set only once toward the set value for the next material.

The roll opening control device of a conventional rolling mill is configured as described above, and since the roll opening is set only once before the roll is bitten into the roll, the lower temperature part of the tip of the sheet is The opening angle is set to be the same as the central part of the plate, and the rolled material is rolled thicker, making it impossible to obtain uniform thickness accuracy over the entire length of the rolled material, resulting in poor product yield.

[Summary of the invention]

The device according to the present invention includes a calculation means that inputs the biting signal of the rolling mill and the rolling speed of the rolled material and calculates the correction time for performing plate thickness correction, and calculates the amount of correction based on the material, temperature, etc. of the rolled material. A calculating means and an inclination signal generating circuit are provided, and the roll opening degree is set to be smaller than the roll opening degree during normal rolling by a correction amount before the rolling mill engages, and the inclination signal after the inclination is used during normal rolling. The present invention relates to a roll opening degree control device that improves plate thickness accuracy near the tip of a rolled material and provides a product with a high yield by configuring the roll to return to one position.

[Embodiments of the invention]

FIG. 1 is a block diagram showing an example of a device according to the present invention. In this figure, (1) to (9) are the same parts as the conventional device shown in FIG. C1O is a pulse transmitter that detects the rolling speed of the rolled material, and is attached to the rotating shaft of the roll (9), and outputs a pulse signal corresponding to the rolling speed. αη is a speedometer side circuit that counts the pulse signal from the pulse transmitter α1 and outputs a signal related to the rolling speed, and (b) is a biting detection circuit that detects biting of the rolling mill and outputs a biting signal. , al are the signal ev related to the rolling speed of the rolled material from the speed measuring circuit α〃 and the jamming detection circuit (6)
This is an arithmetic circuit that inputs the biting signal St from ~ and calculates the roll opening correction time T from both signals. 04 is an arithmetic circuit that calculates the correction amount of the roll opening degree based on the material, temperature, plate thickness, etc. of the rolled material, and (g) is the arithmetic result from the arithmetic circuit CI 葎.

This is a slope signal generating circuit which receives calculation results from the calculation unit 'Ilr◇◆ and generates a slope signal from these calculation results. At 6 o'clock, the setting signal from the roll opening setting device (1),
a subtracter that subtracts the correction amount from the correction amount calculation circuit a4;
F is the slope signal from the slope signal generation circuit (G) and the subtractor α
This is an adder that adds the signal from Q, and its output signal is
It is applied to the arithmetic circuit (4).

The operation of the apparatus constructed in this way will now be explained with reference to FIG. In a continuous hot rolling mill, as shown in FIG. 2, the setting of the roll opening degree for the next material starts when the tail end of the previous material passes through each rolling mill. Here, the value to be set before the rolling material gets caught in the rolling mill is:
In FIG. 1, the roll opening degree setting device (1) is set. The subtractor α→ is a correction from the roll opening correction amount calculation circuit α, which is calculated from the roll opening setting value R8 from the roll opening setting device (1), based on the material, temperature, plate thickness, etc. of the rolled material. The amount α is subtracted and the subtracted value (R8-a) is used as the corrected roll opening setting value via the adder α power to the arithmetic circuit (4) K.
give. As a result, the roll opening degree of the rolling mill is set to be smaller than the roll opening degree (b) during rolling by the correction amount α, as shown in FIG. Thereafter, the next material is bitten into the rolling mill, and a correction signal for the roll opening degree is generated so that the predetermined roll opening degree (a) K is achieved until the next material is bitten into the next rolling mill.

That is, in FIG. 1, the arithmetic circuit α field receives the signal ev related to the rolling speed of the rolled material from the digital speed' measurement circuit (11) and the jamming signal St from the jamming detection circuit (2). The time from the biting of the rolling mill to the biting of the next rolling mill] is calculated. The slope signal generation circuit 0→ creates a correction signal from the correction time T from the calculation circuit Q4 and the correction amount α from the correction amount calculation circuit Q4. This correction signal is added to the set value at the time of biting of the rolling mill by an adder α.
The calculation circuit (4) adds up the force and uses it as the roll opening setting value.
given to. As a result, the roll opening degree is gradually returned to the predetermined roll opening degree (A) during the time T from when the rolling machine is bitten to when the next rolling process is bitten, as shown in Fig. 2. It will be done.

1. In the above embodiment, the electric motor is driven by the roll opening control output to set the roll opening, but a roll opening setting device using hydraulic pressure may also be used. Further, in the above embodiments, a continuous rolling mill is used, but a reversible single rolling mill may be used, and the same effects as in the above embodiments can be obtained.

〔Effect of the invention〕

As explained above, according to the present invention, the roll opening degree is controlled to be small in the low-temperature part of the tip of the plate, so it is possible to improve the plate thickness accuracy near the tip of the rolled material. It is possible to obtain products with high yield.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an example of the apparatus according to the present invention, Fig. 2 is an operation waveform diagram of the apparatus shown in Fig. 1, Fig. 6 is a block diagram of the conventional apparatus, and Fig. 4 is a continuous hot rolling mill. FIG. 5 is an operational waveform diagram of the device shown in FIG. 6. 1...Roll tJlt setting i 9...Roll 13.
...Correction time calculation circuit 14...Correction amount calculation circuit 15
. . . Slope signal generation circuit Note that the same reference numerals in the figures indicate the same or corresponding parts. Agent Patent Attorney Sanro Kimura Figure 3 Figure 4 1115 Figure v: 1-LL#IA Procedural Amendment (Spontaneous) September 20, 1980 To the Commissioner of the Japan Patent Office 1, Indication of Case Patent Application 1982- No. 80258 No. 2, Name of the invention: Roll of a grinding machine - Station control device 3, Person making the amendment Representative: Hitoshi Katayama Department 4, Agent 6, Contents of the amendment (1) "On page 2, line 14 of the specification" (6) is a DIA converter, and (7) is a DIA converter. (6) is a D/A converter, and (7) is a D/A converter. (1) Description rDIA conversion 4 on page 3, line 9!(6)
Correct J as r D / A, conversion sound. that's all

Claims (1)

[Claims] (1) In a device for controlling the roll opening degree of a rolling mill, a calculation means inputs the rolling speed and bite signal of the rolling mill and calculates the correction time for correcting the plate thickness near the tip of the rolled stock. , a calculation means for calculating a correction amount from at least one data of the material and temperature of the rolling material, and a slope signal generation circuit for inputting the signals from each calculation means and generating a slope signal, and Before biting, the opening of the rolls is set smaller than that during normal rolling using the correction amount signal, and after biting, the opening of the rolls is controlled to gradually return to a predetermined roll opening during rolling using the tilt signal. Roll opening control device for rolling mills.