JPS63144813A - Device for preventing loop of hot material of continuous rolling mill - Google Patents

Abstract

PURPOSE:To prevent a loop by correcting the speed of each rolling stand by a speed corrector according to the size of the loop detected by a loop detector. CONSTITUTION:Loop detectors 31, 32 detect a loop and the highest and lowest positions of the loop are found. In case of these highest and lowest positions exceeding a certain level an output is sent to a speed corrector 34 in the case of an arithmetic unit 33 judging. The loop of a hot material 10 between these each rolling stand 1, 2 is prevented by delaying the speed of a 1st rolling stand 1 or quickening the speed of a 2nd rolling stand 2.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention continuously rolls hot materials such as steel bars, wire rods, and shaped steel using a plurality of rolling stands, and prevents the hot materials from bunching up during this rolling process. This invention relates to a hot material sagging prevention device for a continuous rolling mill.

[Conventional technology]

FIG. 3 is a system diagram showing a hot material curl prevention device of a conventional continuous rolling mill. In the figure, 1, 2.3 are the first rolling stand, the second rolling stand, and the third rolling stand, respectively. 4.5.6 is each of these rolling stands 1, 2.3
7.8.9 is a drive device for each motor 4, 5.6, 10 is a heat material as a rolled material, and 21 is a main device that determines the speed command value of each drive device 7.8.9. , a speed setting device 11 for setting the speed of each rolling stand 1, 2.3.
12.13, and successive speed correction devices 14, 15.16 operated by an operator to correct the speed during rolling. Note that 22.23.24 is an adder that adds the successive speed correction value of the next rolling stand to the successive speed correction value of each rolling stand, and 25° 26.27 is an adder that adds the speed to the output of each adder 22.23.24. This is an adder that adds the speed setting values set by the setting devices 11, 12, and 13.

Next, the operation will be explained.

The heat material 10 is placed in the first rolling stand 1. 2nd rolling stand 2.
It is sequentially rolled by the third rolling stand 3. At this time, the rolling position and rolling speed of each rolling stand 1, 2.3 are set in advance before rolling starts. Although the rolling position is not shown, it is usually set using a manual handle, and the rolling speed is set for each stand using speed setting devices 11, 12, and 13.

The set value of the rolling speed is determined by the bus schedule. The pass schedule begins with rolling stands 1 and 2.
．． 3, the exit side cross-sectional area was determined, and the rolling position and rolling speed were determined so that the rolled material 10 would have a predetermined cross-sectional area by each rolling stand 1.2.3.

Theoretically, if you roll with the above settings, a material with a predetermined cross-sectional area should be rolled, but in reality, there are differences in the cross-sectional area of the billet that is the rolling base material, differences in rolling temperature, etc. It is rare that rolling is carried out according to schedule, so in order to keep the mass flow constant, the operator operates the successive speed correction devices 14, 15, 16 on each rolling stand 1, 2.
The mass flow between 3 is kept constant.

Successive speed correction devices 14, 15.16 are operated by the operator when a speed imbalance occurs between the rolling stands 1.2.3 and tension or compression force is applied.
For example, assume that compressive force acts between the second rolling stand 2 and the third rolling stand 3, causing bulges in the heat material 10.

The operator finds this bulge and reduces the speed of the second rolling stand 2 using the successive speed correction device 15). Then, the speed of the upstream stand (first rolling stand 1) also decreases, and the mass balance between the first rolling stand 1 and the second rolling stand 2 remains unchanged, and the speed of the second rolling stand 2 and the third rolling stand decreases. The compressive force between 3 and 3 is eliminated, and the above-mentioned pile is patrolled.

In this way, the speed imbalance between the rolling stands 1.2.3 was resolved by manual intervention by the operator ζτ.

[Problem that the invention seeks to solve]

Conventional continuous rolling mill hot material sagging prevention devices are configured as described above, so it is necessary for the operator to always intervene to correct the speed imbalance, which increases the burden on the operator and increases the burden on the operator. When the pelleter does not pay attention to the pile, or when there are speed imbalances in many places at the same time, it cannot be dealt with, and as a result, the amount of pile of the heating material 10 becomes large, and finally it becomes a cobble, and the heating material 10 This caused problems such as the rolling process becoming unusable and the rolling process having to be stopped in order to process the cobbled material, resulting in an inability to increase production during this time.

This invention was made to solve the above-mentioned problems.It automatically detects the occurrence of bulges in the heating material, issues a warning to the operator, and adjusts the speed to eliminate the bulges. An object of the present invention is to provide a heating material sag prevention device for a continuous rolling mill that can perform control and reliably prevent heating material from cobble.

[Means for solving problems]

The heating material sagging prevention device for a continuous rolling mill according to the present invention includes:
A sag detector is provided to detect sag in the heated material between each rolling stand, and a speed modifier is provided to adjust the speed of one or more of each rolling stand depending on the size of the sag detected. The structure is such that it corrects.

[For production]

The sag detector in this invention detects the sagging state of the heating material between each rolling stand optically and electrically.

It is detected magnetically, thermally, or electrostatically, and when the detected bulge exceeds a predetermined amount, a speed corrector is activated to adjust the speed of the rolling stands upstream or 1 and downstream of the section where the bulge has occurred. It acts to correct the problem and eliminate the clutter.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, 1.2 is the first rolling stand and the second rolling stand among the many rolling stands, 4 and 5 are motors that drive each rolling stand 1.2, and 7-18 is a drive for each motor 4 and 5. It is a device.

Moreover, one bulge detector 31, 32 for detecting bulge in the horizontal direction and bulge in the vertical direction is installed between each of the rolling stands 1 and 2. Reference numeral 33 denotes a sag computation device that receives the outputs of the sag detectors 31 and 32. Based on the output of this sag calculation device 33, a speed corrector 34 adjusts the speed of the first
A speed correction signal is applied to the drive device 7 of the rolling stand 1, whereby the speed of the first rolling stand 1 is corrected and the bulge disappears. Note that, in order to simplify the explanation, the main device is omitted from the illustration. In addition, the bulge detectors 31 and 32 detect the bulge of the heat material electrically, magnetically, silently,
It can be configured by something that detects optically or thermally.

Next, the operation will be explained. Now rolling stands 1 and 2
Suppose that there is an imbalance in speed between them, and a bulge occurs between them.

At this time, the actual situation is that the direction and shape in which the curls occur differ depending on the rolling conditions. Figure 2 shows how this pile looks from above and from the side. Such undulations are detected by undulation detectors 31 and 32, and the highest position fii (MAX) and lowest position (MIN) of this undulation are determined. This highest position (MAX) and lowest position (MI-
N) exceeds a certain level, the calculation device 33
In the case of Fig. 1, the output is output to the speed corrector 34 according to the size of the bulge.
Since the output is output to the rolling stand 1 side), the speed corrector 34 outputs an output in the direction of lowering the speed. In addition, in the case of the downstream direction, the output is output in the direction of increasing the speed.

The speed correction amount ΔV in this case is determined by the following formula.

Δv = f t (MAX, MIN) + f x
(MAX, MIN) However, ft is a term related to the output (MAX, MIN) of the fold detector 32 when viewed from the side, and f2 is a term related to the output (MAX, MIN) of the fold detector 31 when viewed from above.
This is a section regarding MIN).

Although not shown, if there is another stand on the upstream side, the speed is successively corrected in accordance with the speed correction amount ΔV.

In this way, the speed of the first rolling stand 1 is slowed down,
By increasing the speed of the second rolling stand 2,
It is possible to effectively prevent the heat material 10 from bulging between these rolling stands 1. However, even if only one is installed in the direction where there is a high possibility of bulges forming, it is effective for simple burr detection.

Further, the bulge detectors 31 and 32 detect the shape of the bulge itself using, for example, a camera, and determine the amount of speed correction based on this, as well as magnetically detect the bulge shape itself.

Electrical or electrostatic detection means may also be used. Furthermore, the speed correction amount can be simply set to a fixed value in several stages (for example, dog, medium,
It is also possible to decide on the size (small) and select one of them depending on the material position.

Furthermore, as long as the sag detector can measure the occurrence of sag from the rolling load, rolling torque, etc. of the rolling stand 1゜2, the speed may be controlled based on this. .

〔Effect of the invention〕

As described above, according to the present invention, the bulge in the heat material between each rolling stand is always automatically detected by the bulge detector, and the speed of one of the rolling stands is corrected based on the detection output. Since the structure is configured to do so, it is possible to reliably and automatically eliminate the bulges of the heat material, and as a result, not only can the generation of cobbles be reliably prevented, but also the efficiency of rolling production can be greatly improved. There are benefits to be gained.

[Brief explanation of the drawing]

Fig. 1 is a system diagram of a hot material bulge prevention device for a continuous rolling mill according to an embodiment of the present invention, Fig. 2 is an explanatory diagram of the properties of bulges that occur in heat material, and Fig. 3 is a conventional heat material bulge prevention device. It is a system diagram of a prevention device. 1.2.3 is a rolling stand, 10 is a heating material, 31.32 is a sag detector, and 34 is a speed corrector. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. Figure 2

Claims (2)

[Claims] (1) A continuous rolling mill that continuously rolls the hot material using a plurality of rolling stands and prevents the hot material from stacking up between the rolling stands by adjusting the speed of the rolling stands. The material sag prevention device is provided with a sag detector that detects the sag of the heated material between each of the rolling stands, and according to the size of the sag detected by this sag detector, a speed corrector is used to prevent the above mentioned sagging. A hot material sagging prevention device for a continuous rolling mill, characterized in that one or more speeds of each rolling stand are modified. (2) The continuous rolling mill according to claim 1, characterized in that the sagging detector detects sagging based on the rolling load or rolling torque of the rolling stand. Anti-cracking device.