JPH0241717A - Operating method for tension leveler - Google Patents

Abstract

PURPOSE:To reduce a generating ratio of meandering of products by passing through the tension leveler while changing the elongation percentage or tension value of a band metal in sections of prescribed distances in the stage of treating the band metal in a continuous treating line. CONSTITUTION:A bridle driving motor 7 is provided on the inlet side bridle roll group 8 of the continuous treating apparatus and a motor 6 for giving the elongation percentage is disposed on the inlet side bridle roll group 2. When a signal of the changing position for the elongation percentage is outputted from a trucking device, the elongation value changing is started at the point A, the changing is performed on the section between X1 and X, the elongation percentage is kept zero from the point B' to the point D', containing a welding point C. Further, the leveling mill body 3 is released at the point B and rolling reduction of the rolling reduction apparatus 4 is performed at the quick close point D. By this method, because the passing of the plate through the leveler is performed changing the elongation value or tension value in the prescribed range, the meandering generating ratio of the products is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a tension leveler operating method, in particular:
A tension leveler installed at the entrance of various continuous processing lines for rolling, pickling, CAL, chemical conversion, and surface treatment of metal strips to correct the shape of metal strips and prevent them from meandering. This relates to the leveler operation method.

Conventional technology Metal strips are manufactured by hot rolling, etc.
This often results in parts that are malformed.

Since a large number of rolls are provided in various continuous processing lines for metal strips, if the shape of the metal strip is poor, the metal strip will meander due to imbalance in tension in the width direction at each roll portion.

In order to prevent such meandering, the meandering can be prevented by lowering the line width, but this reduces productivity.

In order to solve this problem, a tension leveler is installed on the entry side of various continuous processing lines, and the shape of the metal strip is corrected by the tension leveler to prevent it from meandering.

However, in order to continuously process strip metals in various continuous processing lines, strip metals are welded and used as long objects, such as high carbon steel (C20, 2%), high Mn steel (M
n≧0.5%), high Si steel (S+≧0.3%), high Cr
In hot-rolled steel strips such as steel (Cr≧1.0%), the strength of the welded parts is insufficient, so when bending and stretching is performed using small diameter rolls (diameter≦120) using a tension leveler, the tension This has had the problem of breaking within the leveler. For this reason, the reduction of the work roll of the tension leveler that corrects the welding area is released. However, by opening this role,
A discontinuous portion occurred between a portion where the shape was corrected and a portion where the shape was not corrected, causing meandering.

As a method for solving this problem, for example, as described in Japanese Patent Application Laid-Open No. 63-84729, the work roll is rapidly opened just before the welded part of the metal strip passes through the tension leveler, and then the work roll is quickly opened immediately after passing the tension leveler. A method of lowering the pressure and rotating a tension leveler during this period is also disclosed in JP-A-62-72.
As shown in Japanese Patent No. 431, when the joint of the metal belt approaches the upstream side of the tension leveler, the joint of the metal belt is detected by the upstream metal belt joint detecting device, and the lower roll unit is moved to the intermeshing device. When the detection signal from the strip metal joint detection device is transmitted to a device that moves up and down independently of After passing through the leveler, the lower roll unit rises and returns to normal straightening work due to the joint detection signal from the downstream metal belt joint detection device, while the lower roll unit is stopped by the locking device when the metal belt is passed through. A method of fixing the metal strip in the reverse direction to prevent roll vibration, and a method of bending the metal strip using a tension leveler, scale wobbling force, etc., as described in Japanese Utility Model Application No. 61-162318. In the abnormal part passing device for a continuous processing line for strip metal having a group of small diameter rolls, the abnormal part detection device for the small diameter roll group, a small diameter roll group evacuation VZ@ operated by a signal from the abnormality detection device, and a Using an abnormal part threading device for a continuous metal strip processing line, which is provided downstream of a group of rolls and has a strip metal pressing roller that applies tension to the strip metal pressing roller, and a tension meter roller that sends an activation signal to the strip metal pressing roller. A method of correcting the shape of a metal band has been proposed.

However, in these conventional examples, a tension leveler is placed at the entry side of various continuous processing lines for strip metal, and when correcting the shape, the tension leveler is placed before the welded part of the strip metal passes through the tension leveler. It is only proposed that the work roles of

For this reason, there is no disclosure at all about the relationship between the equipment row of the continuous processing line and the tension leveler. There are no suggestions as to how to operate it.

Problems to be Solved by the Invention The present invention aims to solve the above-mentioned problems, and specifically, when straightening the shape of a metal band using a tension leveler placed at the entrance of a continuous processing line for metal band. , it is difficult to minimize the discontinuity between the straightened part and the unstraightened part before and after the welding part of a metal strip, and to prevent meandering, and research and development are being carried out on methods to solve such problems. This paper proposes a tension leveler operation method that solves the problems such as:

Means for Solving the Problems and Their Effects Namely, the present invention provides that when the shape of a metal strip having a welded part is corrected by a tension leveler disposed at the entrance side of a continuous processing line, the welded part is When introduced into the processing line, the elongation value or tension value is changed for a predetermined distance based on the equipment arrangement on the entrance side of the continuous processing line, and the tension leveler is passed through the plate.

A further explanation of the configuration and operation of the present invention is as follows.

The present inventors investigated the incidence of meandering near the welds of metal bands when the shape is corrected using a tension leveler installed upstream of various continuous processing lines for metal bands.
As shown in Figure 5, the used part of the tension leveler, the unused part, and the discontinuous part where there is a joint between the used part and the unused part of the tension leveler, if there is a joint part between the used part and the unused part, are It was found that the incidence of meandering was higher than in the unused part of the leveler.

Further, in order to prevent such meandering, the conditions for minimizing the number of discontinuous parts with joints were studied, and the present invention was established based on this research.

Further, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is an explanatory diagram of the overall configuration of an example of a continuous processing apparatus used in carrying out the method of the present invention, and FIG. 2 is an explanatory diagram of each control near the welding point of a strip metal according to an embodiment of the present invention. FIG. 3 is an explanatory diagram of the points of change in the method; FIG. 3 is a layout diagram of the entry side of a rolling mill in another embodiment; and FIG. This is a graph showing the relationship between the distance and the meandering occurrence rate when the value is O%, and FIG. 5 is a graph showing the relationship between the usage status of the tension leveler and the meandering occurrence rate.

Reference numeral 1 indicates a metal strip, 2 indicates an inlet priddle roll group, 3 indicates a leveling mill body, 4 indicates a leveling mill rolling device, and 5
6 is a leveling roll, 6 is an elongation rate imparting motor, 7 is a prydle drive motor, 8 is a group of exit side prydle rolls, 9 is a stand on the entrance side of the rolling mill, and 10 is a centering device.

First, as shown in FIG. 1, the continuous processing apparatus used to carry out the present invention is comprised of an inlet prydle roll group 2, a leveling mill main body 3, and an outlet prydle orifice group 8. Entry side priddle roll group 2 is 2a, 2b, 2c
, 2d, and the exit side priddle roll group 8 is composed of 8a, 8b, 8a, 8a, 8b, and 8b, similar to the input side.
A prydle drive motor 7 is provided so that these prydle rolls are driven by a drive motor, and furthermore, a prydle drive motor 7 is provided so that the prydle rolls on the entry side are driven by a drive motor.
An elongation rate imparting motor 6 is connected to a, 2b, 2c, and 2d, and is configured to change the priddle rolls 2c, 2d at predetermined distance intervals so as not to be able to impart an appropriate elongation value to the metal strip 1. There is.

Next, a case in which a belt-shaped metal having a welded portion and a tension leveler are passed through using the apparatus shown in FIG. 1 will be described with reference to FIGS. 1 and 2.

When receiving a signal indicating the change point of the elongation rate value from the tracking device (not shown), the set value change of the elongation rate is started from QA in FIG. 2, and the elongation rate value is changed to 0% in the x1 interval. This change is performed by operating the prydle drive motor 7 to control the prydle rolls 2a, 2b, 2c, 2d.

Next, when the elongation rate value becomes 0% (the elongation rate change end point B' in Fig. 2), the distance is 11ty while the leveling roll is being rolled down.
1 (the section between the quick open point B and the elongation rate change end point B' in FIG. 2). This distance y1 is the first
As shown in the figure, the distance is longer than the distance 11 between the entry side priddle roll 2d and the leveling roll 5 of the leveling mill main body 3.

At point B in the second figure, the leveling mill main body 3 is opened and the welded part (point G in the second figure) is passed through. At the quick close point, the leveling mill is lowered again by the leveling mill lowering device 4. In addition, in the section y between the quick close point and the elongation rate change start point D', only the leveling roll 5 is lowered, and the elongation value is 0.
Set it as %.

Next, the elongation value starts to be applied at point D', and the elongation value is increased in a tapered manner until the elongation value change completion point E, and the target elongation value is achieved at point E. Note that the distance between point B and the dot is set to a length that allows a minimum margin for the biting length of the leveler.

In addition, in the case of a cold rolling mill that is another example, the set value of the elongation rate is changed in the same way as the method shown in Fig. 2, and the elongation rate value is changed to 0% in the section of The ×1 section is the cold rolling mill entrance stand (NO, 1 stand) 9 shown in Figure 3.
The method may be carried out in the same manner as the method shown in FIG. 2, except that the distance Z needs to be longer than the distance Z of the entry side centering device 10.

Although the case of elongation value control has been explained above, in the present invention, even in the case of tension control, the change pattern shown in FIG. The continuous portion can be significantly reduced, and the incidence of meandering due to this discontinuous portion can be significantly reduced.

Example The present invention will be explained below with reference to Examples.

The elongation value change pattern shown in FIG. 2 was applied to the cold rolling mill shown in FIG. 3. The results of investigating the relationship between the distance 2 between the rolling mill entrance stand 9 and the entrance centering device 10 and the incidence of meandering are shown in FIG.

By increasing the distance X to 2Z or more, it was possible to make the occurrence rate of meandering almost equal to or higher than that in the unused portion of the tension leveler.

<Effects of the Invention> As explained above, the present invention provides that when the shape of a metal strip having a welded part is corrected by a tension leveler placed on the entry side of a continuous processing line, the welded part is removed from the continuous processing line. When introduced into the line, the elongation value or tension value is changed for a predetermined distance based on the equipment arrangement on the entrance side of the continuous processing line, and the tension leveler is passed through the plate.

Therefore, according to the method of the present invention, it is possible to significantly reduce the incidence of meandering, and production safety on the line can be achieved.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the overall configuration of an example of a continuous processing apparatus used in carrying out the method of the present invention, and FIG. 2 is an explanatory diagram of each control method near the welding point of a strip metal according to an embodiment of the present invention. Explanatory diagram of change points Figure 3 is a layout diagram of the entry side of a rolling mill in another embodiment, and Figure 4 shows the elongation value when changing the elongation value from the target elongation value to 0% in the apparatus shown in Figure 3. FIG. 5 is a graph showing the relationship between distance and meandering occurrence rate, and FIG. 5 is a graph showing the relationship between the usage status of the tension leveler and the meandering occurrence rate. Code 1... Band-shaped metal 2... Entry side priddle roll group 3...
Leveling mill main body 4...Leveling mill reduction device 5...
Leveling roll 6...Elongation rate imparting motor 7...Pridle drive motor 8...Exit side priddle roll group 9...
Rolling mill entrance stand 10... Centering device

Claims (1)

[Scope of Claims] 1) When the shape of a metal strip having a welded part is corrected by a tension leveler placed on the entry side of the continuous processing line, as the welded part is introduced into the continuous processing line, The tension leveler operating method is characterized in that the elongation value or the tension value is changed for a predetermined distance based on the equipment arrangement on the input side of the continuous processing line, and the tension leveler is passed through the plate. 2) The predetermined distance for changing the elongation value or the tension value is a distance equal to or greater than the distance between an inlet centering device of a continuous processing line for metal strips and a device for guiding the next metal strip. How to operate tension leveler. 3) After changing the elongation value or tension value according to claim 1 with a gradient, releasing the pressure of the tension leveler and passing the plate through the welding area, the elongation value or tension value is changed with a gradient in the same manner as above. A tension leveler operating method characterized in that the tension leveler is started to be lowered by increasing and changing the tension leveler.