JPH0530739B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Industrial Application Field The present invention is directed to a method of meandering a metal strip in a process line in order to eliminate the camber of the metal strip at the entry side or in the middle of the process line. It relates to a device for preventing this.

(B) Prior Art Some conventional metal strip process lines, such as continuous annealing furnaces and metal strip lines, have running distances of 1 to 2 km. Therefore, in order to prevent the metal strip from meandering, the roll is provided with a crown or various steering devices are installed so that the metal strip can track the correct position.

(c) Problems to be solved by the invention Although the use of crown rolls is inexpensive and can be expected to correct meandering, in continuous annealing furnaces, it causes vertical wrinkles called heat buckles to occur in the metal strip in the high temperature section. It's summery. At Metsuki Line etc.
Widthwise warpage and plate buckling that occur in the metal strip cause deviations in the amount of plating deposited. On the other hand, since steering devices are expensive, it is not a good idea to introduce many devices.

(d) Means for Solving the Problems As a measure to prevent the occurrence of meandering in a metal band, the inventors of the present invention have conducted various studies and found that there is a certain relationship between the amount of meandering and the amount of camber. The amount of camber can be defined as the amount of bending C of the steel strip at a certain length L, as shown in FIG. The relationship between the amount of camber and the amount of meandering is shown in FIG.

Figure 6 shows the relationship between the amount of camber and the amount of meandering in the 1st, 2nd, and 7th passes from centering (aligning the running line to the center of the roll) L for each steel strip tension _δT . It is something that
According to this, there is a certain correlation between the amount of camber and the amount of meandering associated therewith, indicating that if the amount of camber is obtained, the amount of meandering can be known.

Based on the above knowledge, the present invention measures the camber of the steel strip before or during the process line such as a continuous annealing furnace, and uses this value to adjust the meandering amount by reducing the tension leveler. It is about controlling the amount.

The device of the present invention is a device that prevents meandering that occurs when a metal strip such as a continuous annealing line or a metal strip runs over a long distance, and includes a camber meter that measures the amount of camber of the metal strip, and a camber meter that measures the amount of camber of the metal strip. It consists of a tension leveler that is connected in series, and a control device that adjusts the amount of reduction of the tension leveler based on the output of the camber meter.

(E) Embodiment FIG. 1 shows an example of a tension leveler 10 installed on the entrance side or in the middle of a process line. Second
The figure shows an example of a camber gauge 20 made of a metal band installed on the entrance side of the tension leveler 10. Figure 3 shows
A block diagram of a measuring device used in the present invention is shown.

First, as shown in FIG. 2, the camber meter 20 is
It consists of three position measuring devices 3', 3'', 3. The camber meter 20 is installed between suitable upper and lower rolls 2 and 4 having a relatively long span of the metal strip 1. Measure the positions of both ends of 1. Based on the measured data, determine the amount of strip camber, predict the amount of meandering based on the relationship shown in FIG.・
It controls the amount of reduction of the leveler.

That is, the tension leveler 10 shown in FIG.
By changing the amount of rolling of the rolls 11 on the left and right sides, the metal strip 1 is subjected to bending and tensioning so as to eliminate the camber of the metal strip 1. Bridle rolls 6 and 8 are provided on the inlet and outlet sides of the tension leveler 10, respectively, to assist in generating tension in the metal strip. As a result, meandering caused by the camber of the metal strip can be suppressed, and the straightness of the metal strip can be improved.

Here, the camber amount of the metal strip is determined by directly measuring it in front of the process line, but the camber amount is measured on another line, such as when winding the metal strip after rolling, and that data is used as the basis. You can also use the method of modifying the canvas.

Next, an experiment was conducted in which a camber was applied to the metal strip 1 by giving a difference in the amount of left and right rolling of the roll 11 of the tension leveler 10. The sample material has a thickness of 0.6mm x width.
Two types of low carbon steel strips of 610 mm, thickness 0.6 mm x width 914 mm were used.

As the tension leveler 10, 11 rolls each having a diameter of 40 mm were arranged as shown in FIG. 1.
A tension of 3 tons is applied to the 610 mm wide steel strip, and a tension of 4.5 tons is applied to the 914 mm wide steel strip, and after passing through the tension leveler 10, both steel strips are
Experiments were conducted with each steel strip in its standard state, in which it was rolled down evenly on both sides so as to undergo 0.2% plastic elongation. That is, one of the left and right rolls of the tension leveler 10 was rolled down from the standard state, and it was investigated how much camber was generated in the steel strip.

The results are shown in FIG. Looking at this result,
It can be seen that when pressure is applied, one-sided elongation occurs on the side to which pressure is applied, resulting in camber. In other words, I found out that I can erase the canvas. Since the amount of reduction and elongation can be expressed linearly, it was found that when creating a canvas for a certain purpose, it can be easily achieved. Incidentally, the results shown in Fig. 4 show that a camber of 5 to 20 mm occurs per 20 m when the leveler reduction deviation is about 0.5 mm.

Based on the above results, we installed an L on the input side of the vertical looper of the electroplating line for the steel strip as shown in Figure 2.
= CCD as a position measuring device at 3 locations at 10m intervals
A camera was installed to measure the position of the steel strip, and the difference in the left and right reduction of the tension leveler shown in Figure 1 installed between the looper and plating tank was tested in advance as shown in Figure 4. Based on experimental data regarding various dimensions and materials, we introduced a system that dynamically sets the bending amount to cancel it out.

As a result, it was confirmed that the camber measured by the electroplating line outlet looper was improved to almost 0. As a result of correcting the camber on the entrance side, meandering within the line has been drastically reduced, so the roll crown (1 to 1.5
mm/diameter), but there was very little meandering.

By making the sink roll straight, board warpage is greatly reduced, and the plating thickness deviation in the board width direction is ±7%.
3%, resulting in a significant improvement in quality, and
It became possible to bring the distance between the electrodes closer together, and the electron consumption rate also improved. In addition, we were able to eliminate almost all the troubles caused by narrowing down the board, which were common in the past.

Although the method of installing a tension leveler on the entry side has been described above, it may also be installed in the middle of a continuous long line and the method of the present invention may be applied downstream.

(F) Effects According to the present invention, it is possible to reduce the camber of the metal strip before passing it through a long process line or during the process, and therefore the meandering due to camber in the long process line can be significantly reduced. . Furthermore, the straightness of the metal strip is improved and the quality is improved.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a tension leveler used for canceling the camber. FIG. 2 is a perspective view of the camber measurement device. Figure 3 is a control system diagram. FIG. 4 is a graph showing the relationship between the reduction amount and the elongation of a camber made using a tension leveler. FIG. 5 is an explanatory diagram of the canvas. FIG. 6 is a diagram showing the relationship between camber and meandering amount. 1... Metal band, 2... Upper roll, 3... Position measuring device, 4... Lower roll, 6, 8... Bridle roll, 10... Tension leveler, 11
...Laura, 20...Kyamba meter.

Claims (1)

[Claims] 1. A device that prevents meandering that occurs when a metal strip is run over a long distance, such as a continuous annealing line or a metal strip line, and includes a camber meter that measures the amount of camber in the metal strip, and a camber meter that is connected to the camber meter. A meandering prevention device for a metal band, comprising a tension leveler and a control device that adjusts the amount of reduction of the tension leveler based on the output of the camber meter.