JPS6156717A - Controlling method of strip shape in rolling process - Google Patents

Abstract

PURPOSE:To elevate a rolling efficiency by detecting a strip shape at the outlet side of the final rolling stand and by grinding a work roll with the roll grinder which is incorporated into each rolling stand based on the detected result. CONSTITUTION:A shape detector 13 of a strip 14 is provided at the outlet side of the final rolling stand F5, also a roll grinder 3 is arranged corresponding to the work roll 1 of each stand F1-F5. When the abnormality of the body elongation at the center of the plate width of a strip 14 or the lug elongation of both edges, etc. is decided from the shape detecting value of the strip 14 detected by the shape detector 13, a control signal is outputted to the roll grinder 3, which is moved to the position corresponding to the abnormality of the work roll 1, and the grinding is performed with reciprocating movement of the prescribed range in the axial direction. In this way, the roll exchange frequency is reduced and the rolling efficiency of a stand is elevated.

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a shape control method when rolling a plate.
In particular, the present invention relates to a method of controlling the shape of a plate by grinding a work roll.

When performing conventional plate rolling, the shape of the material to be rolled is
[F is caused by the generation of so-called waves such as selvage extension) and medium waves (!ri extension). This type of shape defect occurs because the amount of elongation is unrestricted in the width direction of the plate, but there are many factors and the relationships between them are complex, so it is difficult to understand and control them all quantitatively. It is hard to say that it is possible. Among the shape influencing factors, roll deflection by the roll bender, rolling load m, rolling reduction, roll cooling water, etc. can be controlled online and are therefore used in the shape dividing section. However, by controlling these factors, ear elongation, belly elongation, etc. that cannot be corrected may occur in one direction. This is usually caused by the profile of the work roll. Therefore, in the past, when a shape defect such as unilateral edge elongation or sucking elongation occurred, the rolling line was temporarily stopped and the work roll was The roll has been replaced with a work roll that has a different roll crown than the previous one.

Problems to be Solved by the Invention Work rolls are also replaced when abrasion or flaws need to be repaired. The same procedure is used to roughen the rolling stand. Therefore, during such work, the line must be stopped, and it is necessary to replace the rolls while being careful not to damage the rolls, which takes time and results in damage to the rolling line. There were problems with low operating rates and poor productivity. In addition, since the removed work rolls are ground in a roll shop, the work in the roll shop that is not directly used for rolling increases, and in this respect as well, productivity as a whole deteriorates.

Means for Solving the Problems In view of the above-mentioned circumstances, the present invention aims to perform side profile changes that require changes in the roll profile without stopping the rolling line as much as possible. The following methods were explored.

That is, in this invention, a roll grinder for grinding the surface of a work roll is installed in a rolling stand together with the work roll so as to be able to reciprocate in the axial direction of the work roll, and the shape of the strip is detected on the exit side of the final rolling stand. By doing this, the portion of the strip where elongation occurs is detected as the position in the strip width direction, and based on the detection result, the part of the work roll corresponding to the portion where the elongation occurs is ground by the roll grinder. However, by doing this, the roll profile is changed during the rolling process to obtain the shape t11rs.

EXAMPLE Hereinafter, a case in which Sm is corrected for ear extension and belly extension will be described as an example.

The outline of the equipment used is as shown in Figure 1.
Each of the fifth to fifth rolling stands F1 to F5 is configured to have a pair of upper and lower work rolls 1 and a backup roll 2 provided corresponding to each one, and each of the work rolls 1 in each of the rolling stands F1 to F5 is A roll grinder 3 is provided correspondingly.

Here, the roll grinder 3 has a configuration that can be installed online, and an alternative configuration is shown in FIG. 2. That is, the roll grinder 3 shown in FIG. 2 was developed by the present applicants, and the guide shaft 4 is arranged parallel to each work roll 1, and the roll grinder 3 is aligned with the axis of the work roll 1. It is attached to the guide shaft 4 so as to reciprocate in the direction. Each roll grinder 3 has a platen rod 6 that is moved forward and backward toward the work roll 1 by a single pressure cylinder 5, and an extrusion force is applied to the tip of the platen rod 6 by an elastic member 7 such as a spring. A receiving platen 8 is built in, and the platen 8 is configured to press a grinding belt 9 as an abrasive material passing through the front side of the platen 8 against the outer surface of the work roll 1. The grinding belt 9 is made by attaching abrasive grains to a long belt-shaped base material having a predetermined width, and is used to cut the front side of the platen 8 from a feed reel 10 provided in the main body of the roll grinder 3. and is wound on the take-up reel 11. This grinding belt 9
The traveling speed (feeding/winding speed) is 1 to 3 m/min, which is significantly slower than the circumferential speed of the work roll 1, and the direction is set in the opposite direction to the rotation direction of the work roll 1. . Further, a load cell 12 is disposed between the elastic member 7 and the platen rod 6, and the pressing force of the grinding belt 9 is controlled by adjusting the amount of advance of the platen rod 6 by the hydraulic cylinder 5 based on its output signal. It is supposed to be done. Further, although not particularly shown in the drawings, the barrier structure for causing the roll grinder 3 to run along the guide shaft 4 is constructed by a chain or a hydraulic cylinder, etc., and the running speed of the roll grinder 30 is 1 to 2+.
11. /n++n is set. In other words, the roll grinder 3 presses the grinding belt 9 against the work roll 1 with a predetermined pressing force using the platen rod 6 and the platen 7, rotates the work roll 1 in this state, runs the grinding belt 9, and presses the grinding belt 9 against the work roll 1. The work roll 1 is ground by reciprocating (traversing) the work roll 1 within a predetermined range in the axial direction of the work roll 1.

Reference number 13 in FIG. 1 is a shape detector, which is placed on the exit side of the final stand F5. Its shape detector 13
As for, you can use what is widely known from the past,
For example, can water be directed toward the bottom surface of the strip 14?
gi number of nozzles (not shown) are arranged along the board width direction under the strip 14, and each nozzle is connected to the strip 1.
4, and the difference in resistance value between each nozzle and the strip due to the variation in the distance between the two is detected as a voltage value or current value, and the detected value is used to determine the elongation of the edges and the elongation of the belly. You can use whatever configuration you want. While the upper surface of the strip 14 is irradiated with light diagonally from the side using a rod-shaped light Ii (not shown), the upper surface of the strip 14 is irradiated with a television camera (not shown) or the like.
A □'1 shape detector can be used which is configured to image and display changes in the virtual image of the q shape on a special monitor.

The roll grinder 3 and shape detector 13 described above are
A system that processes input signals and outputs control signals to the roll grinder 3! 7Il equipment (not shown). The structure and function of the control device will be explained together with the operation of the rolling mill mentioned above, that is, the method of the present invention.

In plate rolling by the above-described rolling apparatus, the material to be rolled is passed through each of the rolling stands F1 to F5, and rolled into a strip 14 of a desired thickness at the final rolling stand F5. The shape of the strip 14 on the exit side of the final rolling stand F5 is constantly detected by the shape detector 13 during the rolling process, and the work roll 1 is ground according to the procedure shown in FIG. 3 based on the obtained shape information. That is, first, the shape of the strip 14 is determined based on the shape information. In that case, if the shape detector 13 is configured to detect the voltage or current at each part in the board width direction using the aforementioned large number of nozzles, the shape information is expressed as a large number of voltage values or current values (q). Therefore, if all of these detected values are equal, it is determined that the strip 14 is flat and has a good shape, and as a result, no control signal is output to any of the roll grinders 3, and the work roll 1
Sharpen! 1 is not done. In addition, if the detected value at the center in the width direction of the strip is small or changes sharply, this indicates that the center of the strip 14 is clogged and the distance from the nozzle becomes longer, or that the strip is wavy.
L〉Elongation and size IVi. As a result, a control signal is output to the roll grinder 3, and the roll grinder 3 moves to the center of the work roll 1 in the axial direction, where it presses the grinding belt 9 against the work roll 1 with a predetermined pressing force, and It reciprocates within a predetermined range in the direction. That is, when it is determined that the belt is stretched, a calculation is performed to grind the work roll 1 into a concave crown, and the roll grinder 3 is driven or controlled based on the calculation result. Roughly different from the above case, if the detected values on both sides in the board width direction are small or change drastically, both sides of the strip 14 will bulge and the distance from the nozzle will become longer, or one unit will increase. Since it shows that the ears are undulating, it is determined that the ears are elongated. As a result, a pattern setting signal is output to the roll grinder 3, and the roll grinder 3 moves to a position corresponding to both sides of the strip 14 on the work roll 1.
Grinding is performed by pressing the grinding belt 9 against the work roll 1 while reciprocating within a predetermined range in the axial direction.

That is, when it is determined that the edge has elongated, a grinding process is performed to grind the work roll 1 into a convex crown, and the roll grinder S is driven based on the result of the process.

In addition, Su! - The roll that has the strongest influence on the shape of the lip 14 is the work roll 1 of the final rolling stand "5,"
Since the rolling stand on the first stage side becomes somewhat weak, the work roll 1 is ground at the final rolling stand F5 first, and if the defective shape is not corrected, the work roll is ground at the rolling stand one stage before. . In addition, the above-mentioned calculations, f of the roll grinder 3, R'BI3
, the control σ0 and the 'iR determination of the work roll 1 to be ground, etc. are performed by a control device (not shown).

By performing the grinding as described above, the profile of the work roll 1 becomes a concave crown with respect to sucking and elongation, so rolling in the central part in the width direction of the sheet is suppressed, eliminating belly elongation, and Since it has a convex crown against elongation, rolling on both sides in the sheet width direction is suppressed and edge elongation is eliminated. Such grinding can be performed by temporarily stopping the rolling stand that is supposed to grind the work rolls and driving the other rolling stands, so it is possible to perform the shaping piece part without having to temporarily stop the entire rolling line. I can do it.

In carrying out the present invention, defects in the shape of the strip, such as stretching, may be detected visually by an operator. The present invention can also be applied to cases where shape defects other than edge elongation and belly elongation, such as one-sided waves, occur.

Effects of the invention As is clear from the above explanation, method 1 of this invention,
IC! tl:L IIEEIH2i11C#v゛L
lh! J y7f7)tM91' At the same time as detecting, the roll grinder attached to the work roll is adjusted based on the detection result of the shape, and grinds the part on the work roll corresponding to the relatively elongated part. From rolling work rolls, the profile of the work roll can be changed by grinding it, which can correct local strong reductions that cause edge elongation and membrane crimp, and correct shape defects. Since the work rolls are installed while still attached to the stand, the frequency of attaching and detaching the work rolls is reduced, and
In the case of a rolling stand where grinding is to be performed, rolling can be continued, and therefore the number of rolling stops is greatly reduced, making it possible to increase operating rates and productivity to an unprecedented degree.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an apparatus for implementing the method of the present invention, FIG. 2 is a front view of the roll grinder, and FIG. 3 is a flowchart showing one procedure according to the method of the present invention. 1... Work roll, 3... Roll grinder,
13...Shape detector, 14...Strip, F
l, F2, F3, F4, F5...rolling stand. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] A roll grinder that grinds the surface of the work roll is installed in the rolling stand together with the work roll so that it can reciprocate in the axial direction of the work roll, and the shape of the strip is detected on the exit side of the final rolling stand. The portion where the elongation occurs is detected as a position in the sheet width direction, and based on the detection result, the portion of the work roll corresponding to the portion where the elongation occurs is ground by the roll grinder. A method for controlling strip shape in a rolling process, characterized in that: