JPS62286615A - Speed control device for continuous rolling mill - Google Patents

Abstract

PURPOSE:To prevent the plate elongation and plate cut of the steel plate to be rolled due to the error in setting a speed by gradually increasing the torque of each rolling mill driving device at the time of its re-actuation after stopping once plural continuous rolling mills. CONSTITUTION:In the case of rolling a steel plate with plural rolling mills F1-F4, a re-actuation switch 16 is changed over to the side of a re-actuation current control generater 14 in such an output that all rolling mills are increased in its speed on the output signal of MRH1, after stopping the output signal of a rolling speed command generator(MRH) 1 with its outputting so as to stop all rolling mills, and a current limitation reference is outputted from an ordinary current limitation generator 13 simultaneously with the re-actuation by MRH1. In this case, the rate reference of a rate circuit 15 is controlled so as to become such a torque as preventing the plate elongation and plate cut. The re-actuation of the rolling mill by the MRH1 is completed and after completion of the acceleration of the rolling speed of each rolling mill upto the prescribed speed, the switch 16 is changed over to the ordinary current limitation generator 13 side to output an ordinary current limitation reference. The output torques of the driving devices of all rolling mills are gradually increased and the rapid change of the tension onto the steel plate can be prevented.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Object of the Invention] (Field of Industrial Application) The present invention provides a continuous rolling mill for restarting a plurality of continuous rolling mills after stopping them during rolling. The present invention relates to a speed control device.

(Prior art) In a continuous rolling facility consisting of multiple rolling mills, the rolling speed of all rolling mills is adjusted so as not to disrupt the mass flow balance when restarting all rolling mills after stopping them during rolling. It is necessary to accelerate all at the same time at the same rate.

FIG. 2 is a schematic configuration diagram showing an example of a conventional device of this type. In the figure, F1 to F4 are rolling mills, and 1 is rolling mill F1 to F
4, a speed command generator (hereinafter referred to as MR) i for generating a rolling speed signal of -rate, 2-1 to 2-4 is for each of the rolling mills F1 to F4.

Speed command generator (hereinafter referred to as S) that generates a unique rolling speed signal
S RH), 3-1 to 3-4 are multipliers, 4-1
~4-4 is the speed signal 3- from the multipliers 3-1 to 3-4.
1a to 3-4a and speed feedback No. 48 5-1a to 5-48 are input, and the speed controllers 6-1 to 6-4 output a current reference signal depending on the deviation value. 1-4-
Limiters 7-1 to 7-4 limit the output signals of speed controllers 4-1 to 4-4 and current feedback signals 8.
Current controllers 9-1 to 9-2 input signals 1a to 8-4a and output phase control signals according to their deviation values, and input the output signals of current controllers 9-1 to 9-4. , power supply 1
Phase controllers 11-1 to 11-4 that control the output signals of 710-1 to 10-4 are configured by driving devices that drive rolling mills F1 to F4. Next, the operation of the rolling equipment configured as described above will be explained. When increasing or decreasing the rolling speed of the rolling mills F1 to F4 at a constant rate, it is controlled by increasing or decreasing the output signal of 1MRHI.

When increasing or decreasing the rolling speed of each rolling mill, each 5
It is controlled by increasing or decreasing the output signal of SRH2.

(Problems to be Solved by the Invention) In the rolling equipment configured as described above, the output signal of the MRHI is output so as to stop the rolling mill during rolling.

If all the rolling mills are stopped at the same time and the output signal of MRH1 is output so that the rolling mills increase their speed, and all the rolling mills are accelerated at the same rate and restarted, 5SRH2-1 will be activated at the moment of restart. ~
Depending on the speed setting error in 2-4, excessive tension or loops may occur in the rolled material between the rolling mills. Due to excessive tension, there are problems such as plate elongation and plate breakage.

[Structure of the invention]

(Means for Solving the Problems) The present invention relies on gradually increasing the torque of the rolling mill drive device when restarting after a temporary stop during rolling.

It is an object of the present invention to provide a speed control device for a continuous rolling mill that can prevent excessive loops caused by speed setting errors or sheet breakage.

(Function) The present invention lowers the output torque of the rolling mill drive device by current limiting when restarting after a temporary stop during rolling, and sets the current limit value at a rate that does not cause strip elongation or strip breakage after startup. By increasing the speed, the torque applied to all rolling mills when restarting becomes the same, and it is possible to prevent plate breakage caused by speed setting errors of each rolling mill. It is.

(Embodiment) An embodiment of the present invention will be described below with reference to FIG. FIG. 1 is a schematic diagram of a continuous rolling facility consisting of a plurality of rolling mills equipped with a continuous rolling mill speed control device.

13 is a normal current limit generator that outputs a current limit reference during normal times, 14 is a restart current limit generator that outputs a current limit reference during restart, and 15 is a step input signal from the restart current limit generator 14. Outputs a current limit standard that ensures a rate at which the plate does not elongate or break when the rolling mill is restarted. In the rate circuit, reference numeral 16 indicates a switch for switching between the current limit reference during normal operation and the current limit reference during restart.Other components having the same reference numerals as those in FIG. 2 indicate the same parts, and a description thereof will be omitted.

The operation of the embodiment configured as described above will be explained.

In Figure 1, during rolling, the output signal of MRHL is output so that the rolling mills stop, and after stopping all the rolling mills at once,
The output signal of RHL is changed to increase the speed of the rolling mill, and when restarting, the switch 16 is switched to the restart current limit generator 14 side in advance, and the current is limited at the same time as restarting by MRHl. Output the standard. At this time, the rate reference of the rate circuit 15 is controlled so that the torque is such as to prevent plate elongation or plate breakage. Rebooting by MHRl is completed,
After the rolling speed of each rolling mill reaches a predetermined speed and acceleration is completed, the switch 16 is switched to the normal current limit generator 13 side, and a normal current limit reference is output. The current limit reference signal becomes a reference signal to the limiter 6 of each rolling mill, and the output signal from the amplifier 4 is limited to the reference signal and driven! The output torque of position 11 is limited.

Therefore, when restarting the drive device 11 after a temporary stop during rolling,
The output torque of each rolling mill increases gradually depending on the output signal from the restart current limit generator 14 and the rate circuit 15, so the output torque of each rolling mill drive device gradually increases, and the speed of each rolling mill increases. This prevents sudden changes in the tension on the rolled material due to setting errors, and prevents plate elongation and plate breakage.

〔Effect of the invention〕

As described above, according to the present invention, when restarting a continuous rolling mill after a temporary stop during rolling, excessive loops, plate elongation, or plate breakage due to unbalanced rolling speed settings for each rolling mill can be prevented. I can do that.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a speed control device for a continuous rolling mill according to the present invention, and FIG. 2 is a configuration diagram of a speed control device for a conventional continuous rolling mill. 1...M RH, 2.5SRH1 3...Multiplier, 4...Speed controller, 5...
・Speed feedback signal, 6...Limiter, 7.Current controller,
8...Current feedback signal. 9... Phase controller, 10... Power supply device, 11
... Drive device, 13... Normal current limit generator, 14... Restart #I current limit generator. 15... sea 1~circuit, 16... switching device. Agent Patent Attorney Nori Chika Yudo Hirofumi Mitsumata

Claims (1)

[Claims] In rolling equipment consisting of a continuous rolling mill, a normal current limit generator generates a normal current limit standard for limiting the output torque of the rolling mill drive device, and a normal current limit generator that generates a current limit standard in normal times to limit the output torque of the rolling mill drive device, and a normal current limit generator that generates a current limit standard in normal times to limit the output torque of the rolling mill drive device, and a normal current limit generator that generates a normal current limit standard that limits the output torque of the rolling mill drive device, and after the rolling mill is temporarily stopped in the middle of rolling. a restart current limit generator that generates a current limit reference upon restart of the restart current limit generator; a rate circuit that converts the output signal of the restart current limit generator into a rate signal; and a signal from the normal current limit generator and the rate circuit. The rolling mill has a switching device that switches the signal from the switching device, and the rolling mill is operated by a speed setting error when restarting the rolling mill after the rolling mill stops once in the middle of rolling, depending on the current limit signal switched by the switching device. A speed control device for a continuous rolling mill, which is characterized by preventing excessive loops in between, plate elongation, and plate breakage.