JPS5832510A - Controlling method for bend of slab in inline reduction - Google Patents

Abstract

PURPOSE:To prevent a bend of rolled slab, by computing reduction quantity from the position and thickness of the end surface of the slab detected at the outlet side of a roll in rolling a continuously casted ingot into a slab by an inline reduction roll successively. CONSTITUTION:A continuously cast ingot 2 coming out from a continuous casting-machine 1 is pressed down into a slab 6 directly by an inline reduction roll 3a, and enters the next reduction roll. At this time, gaps between the standard points 7 and 8 provided to the down-stream side of rolling and both end surfaces of the slab 6 are detected respectively, and the thicknesses at both end surfaces of the slab 6 are detected simultaneously. Both detected values are inputted to an operator 12 to obtain the difference between the reduction quantities at both end parts of the slab 6. Both of press down forces of hydraulic cylinders 14a and 14b provided to both end parts of an upper roll of the reduction roll 3a are properly controlled respectively, by the action of a hydraulic controlling device 13 depending on said difference, to press down the slab 6 uniformly in the width direction without causing a bend, thereby sending the slab 6 to the next reduction roll.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling slab bending in in-line reduction following continuous casting.

A slab obtained by continuously casting molten metal using a continuous casting machine,
Subsequently, attempts have been made to obtain slabs of various thicknesses by applying reduction with in-line reduction rolls, but this method is difficult due to non-uniformity in temperature in the width direction of the slab or non-uniformity in the shape of the slab. There is a problem that the slab bends when the slab is rolled down, and when this phenomenon occurs, the slab comes off the rolling line track, making it impossible to carry out in-line reduction.

An object of the present invention is to provide a slab bending control method that eliminates and improves the drawback that rolling cannot be performed due to slab bending in in-line reduction following conventional continuous casting. The above objects can be achieved by providing a control method according to the scope of the present invention. That is, the present invention, when producing slabs of arbitrary thickness by ink reduction following continuous casting, uses reference points placed opposite to each other on both sides of the reduction line on the exit side of rolling by the reduction rolls. When the slab passes through the mutually connecting temporary NjliI, the distances between both sides of the slab and the opposing reference points are detected, and the thickness at both sides of the slab rolled by the reduction rolls is measured. After detecting the respective distances and thicknesses, the amount of reduction to be applied to both sides of the traction roll is calculated by calculation, and the amount of reduction to be applied to both sides of the traction roll is calculated in accordance with the amount of reduction calculated in this way. The present invention relates to a slab bending control method in an in-line reduction process 7 following continuous casting, which is characterized by applying reduction.

Next, the present invention will be explained in detail.

Figure 1 is an explanatory diagram (plan view) showing the situation where slab bending occurs due to in-line reduction following conventional continuous casting. When the slab is rolled down in step 3, as mentioned above, due to the non-uniform temperature in the width direction and non-uniform shape of the continuous slab before rolling, the slab bow after rolling bends to the left in Fig. 1, for example. A phenomenon in which the rolling material travels in the downstream direction of rolling occurs, resulting in the drawback that rolling cannot be performed continuously with the next rolling reduction roll S, or that the rolling material moves out of the conveying roll line.

As a result of various investigations to eliminate the above-mentioned drawbacks, the inventor Misaki found that
In the process of in-line reduction of the cast slab after casting, reference points are set opposite to each other on both sides of the slab on the downstream side of rolling of each paste reduction roll, and the reference points are applied with, for example, laser ultrasonic waves or a touch roll method. Distance needles are installed to measure the distance between the reference point and the opposing sides of the slab to detect the slope of the slab. If each distance is detected, it is possible to accurately detect the deformation of the slab, but if necessary, it is possible to detect the deformation of the slab even if the distance is measured only on one side of the slab, thereby achieving the object of the present invention. be able to.

On the other hand, the thickness of the left and right ends of the slab is detected, and the distance and thickness values are sent to a computer and calculated to calculate the amount of reduction that should be applied to each of the left and right ends of the slab, and the reduction is performed according to the calculated values. Determine the amount of reduction with the roll,
The necessary in-line reduction can be achieved by modifying and controlling one section of the slab.

Next, the present invention will be explained using the drawings.

Figure 1 is an explanatory diagram showing an overview of one embodiment of the arrangement and connection of various equipment directly used in carrying out the method of the present invention, and the continuous caster/strand slab is a reduction roll ja I.
It is rolled down by Ic, becomes a slab 6, and is guided to the next gluing reduction roll (not shown). A reference point set opposite both sides of the slab 60 on the rolling downstream side of the reduction roll 31? , both sides 9 of the slab 10 intersect with the imaginary line connecting f.
, 10 and the reference point t, respectively, are measured by installing distance meters at the reference point 1.1.

On the other hand, in FIG. 3, which shows a longitudinal section of the reduction roll 3a device, the thickness of the left and right end portions of the slab 6 is detected using a nine-roll gap measuring device //a, //b[j9] using, for example, a differential transformer. Then, the numerical values of the measured distance and each thickness of the slab are sent to a computer, the amount of roll reduction of at least one of the left and right rolls is determined, and the reduction blades of the hydraulic cylinders /la and /lb are controlled by the hydraulic control device 13. This can correct and prevent bending of slabs.

According to the present invention, when the slab 6 bends to the left in FIG. Reducing the blade corrects the leftward bending of slab 1.

The choice between increasing or decreasing the reduction blade is as follows:
Determine which side of the hydraulic cylinders /daa, /hirosu is closer to the standard set thickness of the slab, and increase or decrease the hydraulic cylinder that is farther from the standard set thickness to reach the standard set thickness. You can choose based on the policy of bringing it closer.

Next, the method of controlling slab bending by the control method of the present invention will be explained with reference to the plan view and front view of FIGS. 9(A) and 9(B).

Is the reference distance between the slab side and the reference point l□s reference point?
, t and the respective distances from the sides 9 and 10 of the slab to I!
,,1. shall be. The reference gap for the reduction roll is t. The measurement gaps of the reduction rolls provided with hydraulic cylinders /#a and /4ib are respectively 11 and 1 U, and the reduction blades of the hydraulic cylinders /la and /lb are Pa and Pb, respectively.

For example, if the slab is bent toward the reference point after being rolled by a reduction roll, then 10 11<orlo 1
2>0. In this case, to tl>o, and 1. −
If 12÷O, the above-mentioned burr can be corrected by increasing the reduction blade Pa. On the other hand, t. −t7*O, and t.

If -t is <0, the -edge IIi is corrected by reducing the reduction blade pb.

The above-mentioned determination of the amount and selection of each reduction blade is made based on the result of calculation by a computer, and a command is given to the hydraulic control device to select the negative pressure reduction blade.

In this way, bending of the wrist tube can be prevented and corrected by controlling the left and right rolling blades so that the thickness is as close to the standard as possible.

As described above, according to the method of the present invention, in the in-line reduction process of continuous slabs made of steel, copper, aluminum, or those metals as main components, it is possible to carry out reduction reduction, which was previously impossible due to bending of the slab. , cost reductions are achieved by shortening processes and greatly improving productivity.

[Brief explanation of drawings]

FIG. 1 is an explanatory plan view showing the bending of a conventional in-line reduction pest control slab; FIG. Figure 3 is a front explanatory view of the beam reduction roll, Figure 9 (4). (B) is an explanatory plan view and an explanatory front view of a reduction roll used for carrying out the method of the present invention, respectively. /・!・Continuous casting machine, ko... Continuous casting piece, 3. Ja,! ...
Reduction roll, ge, 6...slur y, t, t.
...Reference point, 9,10...Slab side, //a, //
b...Roll Seki FA61! I-status device, /ko...computer, /3...hydraulic control device, 17゜yu...distance between reference point and slab side, 1. ．． 1U -- Upper and lower roll gaps, /41a, /Dab... Hydraulic cylinder, Pa,
Pb...Reduction blade. Patent applicant Kawasaki Steel Corporation Kinsha

Claims (1)

[Claims] L In order to manufacture slabs of arbitrary thickness by in-line reduction following continuous casting, we draw the imaginary lines connecting nine reference points, which are provided oppositely on both sides of the reduction line, on the rolling exit side of the reduction rolls. The distances between both sides of the slab and the respective opposing reference points are detected as the slab passes across, and the thicknesses at both sides of the slab rolled by the reduction o-sr K are respectively detected. After the detection, the amount of reduction to be applied to both sides of the reduction roll is calculated based on the detected distance and thickness, and in-line reduction is performed according to the amount of reduction calculated in this way. Control method for slab bending in/in-line reduction following continuous casting with fIk.