JPS6240920A - Plate width control method for hot rolling stock - Google Patents

Abstract

PURPOSE:To realize the correct plate width control without being influenced by the disturbance at temp. measuring time by providing the temp. detector to perform the temp. detection of a hot rolling stock just the above or just the below of a vertical roll and by controlling the roll gap based on the detected temp. thereof. CONSTITUTION:A temp. detector 2 is provided near the upper side or lower side of the roll center of a vertical roll 1 and within the range of 50cm at the upper stream side and 100cm at the downstream side in order to control the width rolling reduction of a hot rolling stock M by a vertical rolling mill correctly by depending it on the measuring temp. The plate width variation based on the temp. change of the rolling stock M is forecasted in a plate width control arithmetic unit 3 and the gap of the roll 1 necessary for denying this variation is operated. The arithmetic unit 3 outputs the arithmetic result to the rolling reduction control device as a signal. The correct plate width control not being influenced by the disturbance at the temp. measuring time can thus be realized.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is a method for controlling the width of a hot rolled material by detecting the temperature of the hot rolled material and controlling the roll gap of a vertical rolling mill based on the detected temperature. Regarding the method.

[Conventional technology]

As a method for controlling the width of this kind of hot-rolled material, JP-A-54
There is a method disclosed in No.-134059. In this method, when performing width reduction of hot rolled material, a temperature sensor is installed at the entry side of the vertical rolling mill, generally about 5 meters upstream, and the output value is fed forward to control the roll gap of the vertical rolling mill. are doing. In order to feed forward, it is necessary to track the progress of the hot rolled material, and this is done by time-integrating the circumferential speed of the vertical rolls of the vertical rolling mill.

[Problem that the invention seeks to solve]

In order to accurately control the strip width depending on the measurement temperature using the conventional method described above, it is necessary to accurately track the temperature measurement point of the hot rolled material. However, tracking of hot-rolled materials involves large measurement errors due to the following reasons. First, the rolling reduction of a vertical rolling mill is very small. For this reason, slips are likely to occur between the vertical rolls and the rolled material, and this slip appears as a length measurement error. Secondly, in order to track the progress of the rolled material, it is necessary to multiply the circumferential speed of the vertical roll by the backward movement rate. However, since the edge portion of the rolled material is deformed three-dimensionally in a dogbone shape, it is difficult to determine an accurate value of the backward advance rate than the widthwise reduction rate. Therefore, errors occur depending on the value of the backward movement rate.

For the above reasons, the conventional method has difficulty in tracking, and it is difficult to perform control dependent on the measured temperature.

The present invention solves the above problems by changing the position of the temperature detector, and provides a strip width control method that can control the strip width of hot rolled material extremely accurately depending on the measured temperature. purpose.

[Technical means to solve the problem] In order to achieve the above object, the method for controlling the width of hot rolled material according to the present invention:
Upstream side 501M, downstream side 100C from the upper or lower side of the roll center of a vertical rolling mill that performs width reduction of hot rolled material
The present invention is characterized in that a temperature detector for detecting the temperature of the hot-rolled material is provided within a range of 1n, and the roll gap of the vertical rolling mill is controlled based on the output of this temperature detector.

This is because the temperature detector is installed within a range of 50 crn upstream from the roll center of the vertical rolling mill and 100 m downstream from the roll center in order to eliminate disturbances caused by these devices as much as possible, and there is no need to perform feedforward or feedback control.

However, in order to minimize the influence of response delay, it is preferable to install the temperature detector within the upstream side 50z.

[Effect]

Since the temperature detector is located above or below the roll center of the vertical rolling mill within a range of 50 m upstream and 100 m downstream, the progress of the hot rolled material can be tracked without being tracked.
The roll gap of the vertical mill is immediately controlled based on the output of the temperature sensor. Some vertical rolling mills have excellent responsiveness, so the response delay is negligible compared to the tracking error, and therefore, according to the present invention, the strip width can be controlled extremely accurately.

〔Example〕

Examples will be described below with reference to the drawings.

In carrying out the present invention, a vertical rolling mill with excellent control responsiveness of a rolling system, such as a vertical rolling mill with a hydraulic rolling system, is used.

A temperature detector 2 is provided directly above the vertical roll l of this vertical rolling mill, and its output is input to a strip width control calculation device 3.

The strip width control calculation device 3 performs appropriate calculation processing based on the output value of the temperature detector 2, and outputs a control signal to the rolling reduction control device of the vertical rolling mill. The draft control immediately responds to this signal and changes the gap of the vertical rolls 1.

By the way, there are various calculation processing methods by the sheet width control calculation device 3, but in this embodiment, the processing is performed with reference to the relationship diagram of material temperature change and sheet width variation shown in FIG. The relationship diagram is for rolling a plate thickness of 50 mm at 1000°C to 30 cm. The vertical axis shows the change in plate width (wn), and the horizontal axis shows the temperature change (wn).
℃), a large number of curves are provided for each standard plate width B.

First, when the plate width control calculation device 3 receives an input regarding the temperature of the hot-rolled material, the difference between the measured temperature and the basic temperature or the cumulative total of the differences up to now is calculated, as shown in Fig. 4. The amount of plate width variation that occurs due to material temperature changes is predicted with reference to the relationship diagram. Next, the sheet width control calculation device 3 calculates the gap of the vertical rolls 1 necessary to cancel out the predicted sheet width fluctuation amount, and outputs the value as a signal to the aforementioned rolling down control device.

In this way, the gap between the vertical rolls is controlled based on the measured temperature, but since the temperature detector is located directly above or below the vertical roll and no tracking information is required, the computational processing system is very simple. It has become.

When referring to the above-mentioned relationship diagram, the range of application can be further expanded by preparing correction coefficients for each factor such as material, rolled material dimensions, average material temperature, etc.

As shown in FIG. 1, a horizontal roll 4 is installed 3 m downstream of the vertical roll 1, and an upper desk header 5a and a lower desk header 5b are installed upstream. Desuke headers 5a and 5b located on the upstream side (normal pressure 5-10
The descaling water jet (kg7cm") causes water to scatter, which may cause disturbance to the temperature measurement.
In the embodiment, the temperature detector 2 and desk headers 5a and 5b
Between the side sprays 6a, 6b and the fusari curtain 7
We are working to eliminate disturbances by preparing M is a rolled material.

〔Effect of the invention〕

According to the present invention, the temperature sensor is provided directly above or below the vertical roll, and measurement errors can be minimized and controlled. Furthermore, since tracking information is not required, the control system is also simplified.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of an apparatus for carrying out the present invention, Figure 2 is a side view of Figure 1 with disturbance prevention measures taken, Figure 3 is a plan view of Figure 2, and Figure 4 is a vertical roll. FIG. 2 is a diagram showing the relationship between material temperature change and plate width variation, which is referred to in gap control. ■...Vertical roll, 2...Temperature detector, 3...Plate width control calculation device, 4...Horizontal roll, 5a #5
b...Desuke header, 6as6b...Side spray, 7...Fusari curtain Figure 1 Figure 2 Figure 4

Claims (1)

[Claims] (1) From the upper or lower side of the roll center of a vertical rolling mill that performs width reduction of hot rolled material, upstream side 50 cm, downstream side 1
A plate of hot-rolled material, characterized in that a temperature detector for detecting the temperature of the hot-rolled material is provided within a range of 0.00 cm, and the roll gap of a vertical rolling mill is controlled based on the output of this temperature detector. Width control method.