JPH1034204A - Tension controller for reversible rolling mill - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably keep the tension of a strip at the time of starting and during normal operation and to enable control by respectively control dancer rolls in constant torque control mode at the time of starting a line and in regular position control mode at the time of normal operation. SOLUTION: First, by controlling a 1st driving motor 6 based on a torque command with a 1st dancer roll driving device 9, the height position of a 1st dancer roll 4 is adjusted. At this time, in the load current for the 1st driving motor 6, a current signal is fed back to an arithmetic controller 14 and, simultaneously, at the height position of the 1st dancer roller 4 also, a position signal is fed back to the arithmetic controller 14 through a position sensor 15. At the point of time when it enters the normal state, the arithmetic controller 14 becomes the regular position control mode and the speed command is issued to the 1st dancer roll driving device 9. At the point of time when it reaches the normal operation after starting, the 1st and 2nd dancer rolls 4, 5 are changed to the regular position control mode and controlled with the arithmetic controller 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a tension control device for a reversible rolling mill.

[0002]

2. Description of the Related Art Conventionally, the tension control of a strip in a single-stand reversible rolling mill used for rolling a strip such as a steel plate is performed by a tension reel (not shown) installed on the front and rear surfaces of the rolling mill to rewind and rewind a coil. This is generally performed by controlling the torque of a drive motor of a reel. In a multi-stand hot rolling mill, it is general to control the strip tension by a looper provided between the stands,
In the single-stand reversible rolling mill described above, an example of installing such a looper has not been found in the past.

[0003]

Incidentally, in the above-described single-stand reversible rolling mill, when starting up, a tension fluctuation occurs between the rolling mill and the reel due to factors such as static friction. This tension fluctuation is less likely to cause breakage or sag when the strip is thick, but has the disadvantage that breakage or sag occurs when the strip is thin.

[0004] It is an object of the present invention to provide a tension control device in a reversible rolling mill that has solved the above-mentioned problems of the prior art.

[0005]

SUMMARY OF THE INVENTION The present invention is an apparatus for controlling the tension in a reversible rolling mill comprising a multiplex type rolling mill for rolling a strip and tension reels disposed before and after the multiplex type rolling mill. A dancer roll is installed between the rolling mill and the tension reel, and the dancer roll is controlled in a constant torque control mode based on a tension command value of the tension reel when the rolling mill is started, and in a fixed position control mode during normal operation. A tension control device in a reversible rolling mill, wherein a tension control device is provided.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic diagram showing an embodiment of the present invention. In this figure, 1
Is a single stand for rolling the strip S and is a multiplex type reversible rolling mill (hereinafter simply referred to as a rolling mill), 2 is a first reel provided on the front face of the rolling mill 1, and 3 is a first reel provided on the rear face of the rolling mill 1. 2 reel. Reference numeral 4 denotes a first dancer roll disposed between the rolling mill 1 and the first reel 2, and reference numeral 5 denotes a second dancer roll disposed between the rolling mill 1 and the second reel 3.

Reference numeral 6 denotes a first drive motor, which adjusts the height position of the first dancer roll 4 by raising and lowering a wire 8 via a drum 7. Reference numeral 9 denotes a first dancer roll driving device that controls the first driving motor 6. Reference numeral 10 denotes a second drive motor, which adjusts the height position of the second dancer roll 5 by raising and lowering the wire 12 via the drum 11. Reference numeral 13 denotes a second dancer roll drive device for controlling the second drive motor 10.

Numeral 14 denotes an arithmetic control unit such as a computer. When the rolling mill is started, a tension command value T of the tension reel is set.
In the constant torque control mode, and in the regular position control mode during normal operation. In addition, 15,
Reference numeral 16 denotes a position sensor such as a pulse transmitter coupled to the rotation shafts of the first and second drive motors 6 and 10. The configuration of this tension control system will be described below with reference to the first dancer roll 4 as an example.

That is, as shown in FIG. 2, a reel tension set value T is set in advance in the arithmetic and control unit 14, and when the line is started, the arithmetic and control unit 14 is in a constant torque control mode. , And issues a torque command to the first dancer roll driving device 9. The first dancer roll driving device 9 controls the first driving motor 6 based on the torque command.
To adjust the height position of the first dancer roll 4. At this time, the load current to the first drive motor 6 is fed back to the arithmetic and control unit 14 as a current signal I, and at the same time, the height position of the first dancer roll 4 is arithmetically controlled as a position signal P via the position sensor 15. This is fed back to the device 14. Thereafter, when the normal state is entered, the arithmetic and control unit 14 enters the fixed position control mode and issues a speed command to the first dancer roll driving device 9.

In this way, when the line is started, a difference occurs between the rolling mill 1 and the first reel 2 and the second reel 3 when the rolling mill 1 is started due to factors such as static friction. Since tension fluctuation occurs in S,
The first dancer roll 4 and the second dancer roll 5 are controlled by the arithmetic and control unit 14 in a constant torque control mode, and serve to keep the tension of the strip S constant. Thus, the line can be started without causing breakage or sagging. Then, when reaching the normal operation after the startup, the arithmetic and control unit 14 controls the first dancer roll 4 and the second dancer roll 5 by switching to the fixed position control mode. As a result, the tension of the strip S becomes the first
The control is stably performed by the reel 2 and the second reel 3.

[0011]

[Example] The material is stainless steel and the width is 900 mm.
The apparatus of the present invention was applied when a 0.05 mm-thick strip was rolled by a 20-layer reversible rolling mill. FIG. 3 shows an example of the transition of the change in the tension of the strip at the time of startup in the first pass. The constant torque control mode was entered when the tension was applied before the line startup time t _{0, and the} mode was switched to the normal fixed position control mode when the time t ₁ at which the tension was stabilized became 3 seconds. As a result, it was possible to perform rolling with very little fluctuation in tension.

[0012]

As described above, according to the present invention,
A dancer roll is arranged between the rolling mill and the reel, and this dancer roll is in a constant torque control mode when the line is started,
In addition, since the control is performed in the fixed position control mode during the normal operation, it is possible to control the strip while maintaining the tension of the strip at the start and during the normal operation stably.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an embodiment of the present invention.

FIG. 2 is a block diagram illustrating an example of a configuration of a tension control system according to the present invention.

FIG. 3 is a characteristic diagram showing an example of transition of a change in tension when the present invention is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rolling machine (Multiple rolling mill) 2 1st reel (1st tension reel) 3 2nd reel (2nd tension reel) 4 1st dancer roll 5 2nd dancer roll 6 1st Drive motor 7, 11 Drum 8, 12 Wire 9 First dancer roll drive 10 Second drive motor 13 Second dancer roll drive 14 Arithmetic control unit 15, 16 Position sensor S strip

Claims (1)

[Claims] An apparatus for controlling tension in a reversible rolling mill comprising a multiplex type rolling mill for rolling a strip and tension reels disposed before and after the multiplex type rolling mill, wherein a tension between the rolling mill and the tension reel is controlled. In addition to installing a dancer roll, at the start of the rolling mill in the constant torque control mode by the tension command value of the tension reel,
A tension control device for a reversible rolling mill, further comprising an arithmetic control device for controlling the dancer roll in a fixed position control mode during normal operation.