JPH10328710A - High-reduction rolling method and rolling equipment therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-reduction rolling method by which high rolling reduction is obtained with a usual rolling device which is hard to be damaged, easily maintained and, consequently, a rolling line is shortened and rolling equipment therefor. SOLUTION: Between two rolling rolls 11 in one rolling mill 10, the tip part of a rolled stock 13 is bitten at a prescribed thickness h11 at a 1st pass, sloping rolling for forming the length L11 of slope-shaped tip part while gradually opening the roll gap G10 of the rolling rolls is executed by reduction in forward rotation and stopped at the end part of slope. Next, the rolled stock is bitten at the prescribed thickness h12 and the sloping rolling for forming the length L13 of the slope-shaped tip part having the thickness h13 so that the tip part of the rolled stock is further thinned at the 2nd rolling pass while gradually closing the roll gap of the rolling rolls is executed by reduction in backward rotation. Furthermore, the rolling whose biting rolling reduction is higher than that of the usual rolling at the 3rd rolling pass is executed in the forward rotation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-pressure rolling method for obtaining a large amount of reduction and a rolling equipment therefor.

[0002]

2. Description of the Related Art In the rolling of a normal rolling mill 1, an allowable rolling reduction for biting of a leading end of a rolled material 3 between two rolling rolls 2 is as shown in a schematic diagram of FIG. A bite angle greater than the friction angle cannot be obtained. Therefore, the bite reduction amount is limited to a small value. 8 (a) and 8 (b), the thickness of the steady portion of the rolled material 3 conveyed in FIG. 8 is H0, the thickness after rolling is h1, the bite angle is θ1, the friction coefficient is μ, and the reduction at this time. The amount is Δh1. This biting angle θ1 is
If it is smaller than the friction angle of the coefficient of friction, it can be engaged, and if it is larger, it slips and cannot be engaged. This is tan
Under the condition of .theta.1 <.mu., the amount of reduction is determined by the formula of .DELTA.h1 = H0 -h1 and the bite angle. In other words, all the conditions are determined by the frictional condition of the roll, and it is impossible to reduce the amount of reduction any more. For this reason, reverse rolling in which the rolled material is reciprocated and rolled is performed, but there is a problem that the rolling line becomes long.

On the other hand, as a rolling facility having a rolling reduction larger than a normal maximum rolling reduction, a pune ratari mill has been conventionally known (for example, “Overview of 600 mmφ hot single pune tarari mill”, Ishikawajima Harima Technical Report) , Showa 4
August 4th, "UTHS system-atechnology to produce ho
t strip in thin gauges ”, Metallurgical Plant Tech
nology International 1994, Japanese Patent Publication 46-2960
No. 5, "Planetary rolling mill", and JP-B-55-37324, "Complete rolling auxiliary corrugation device for rear end of material in planetary rolling mill," etc.).

[0004]

However, in the Pune Latari Mill, the rolling equipment itself has a special and complicated structure, the impact is large because the small-diameter roll is applied to the plate at high speed, and the components (particularly, small-diameter roll bearings, etc.) Life is short,
There was a problem that was not suitable for mass production type rolling equipment.

[0005] The present invention has been made to solve these various problems. That is, an object of the present invention is to provide a high-pressure rolling method and a rolling equipment capable of obtaining a high rolling reduction with a device which is not easily damaged and which is easy to maintain, thereby shortening a rolling line.

[0006]

According to the present invention, the leading end of a rolled material is bitten to a predetermined thickness in a first rolling pass between two rolling rolls in one rolling mill. While sequentially opening the roll gap, perform inclined rolling to form an inclined tip portion length under normal rotation pressure, stop at the end of inclination, then bite at a predetermined thickness, while sequentially closing the roll gap of the rolling roll. In the second rolling pass, inclined rolling is performed under a reverse rolling pressure so as to form a slanted tip portion length so that the leading end of the rolled material becomes thinner. In the third rolling pass, the biting pressure is reduced from the normal rolling. A high-pressure rolling method is provided, in which high-volume rolling is performed under normal rolling pressure.

[0007] According to the method of the present invention, the tip of the rolled material is bitten to a predetermined thickness in the first rolling pass by using a normal one rolling mill rolling between two rolling rolls. Performing the inclined rolling to form the inclined tip portion length while sequentially opening the roll gaps of the rolling rolls under the normal rotation pressure, stopping at the end of the inclination, then biting in at a predetermined thickness, and setting the roll gap of the rolling rolls. In the second rolling pass, inclined rolling is performed under a reverse rolling pressure to form a slanted tip portion length such that the leading end of the rolled material becomes thinner in the second rolling pass, and the third rolling pass is further performed under a normal rolling pressure. By doing so, the tip end of the rolled material can be tilted down by the first and second forward and reverse tilt rolling in one rolling mill without rolling the entire length of the rolled material at one time. As a result, an inclined tip portion length having an inclined plate thickness in which the tip thickness is made smaller than a value obtained by subtracting the amount of reduction from the normal allowable friction from the tip thickness having a large gradient is formed. As a result, in the third rolling pass, rolling with a higher biting reduction than in normal rolling can be performed. Further, since a normal rolling mill is used, the rolling mill is hardly damaged and easy to maintain. Furthermore, a high rolling reduction can be obtained with a small number of rolling mills (single or plural) as compared with a normal tandem rolling mill, and the entire rolled material does not move back and forth. Can be significantly shorter.

According to a preferred embodiment of the present invention, the thickness of the inclined front end of the third rolling pass in the one rolling mill is made thinner than the steady thickness of the rolling mill so that the third rolling pass is reduced. Occasionally, rolling down is performed from the inclined portion behind the inclined tip. According to this method, the thickness of the inclined tip is smaller than the steady thickness of the rolling mill, that is, the roll gap between the third rolling rolls can be set between the inclined tip thickness and the steady thickness. Even in the flash rolling of the rolling pass, the bite reduction from the inclined portion behind the inclined tip portion can be further increased.

In the tandem rolling mill comprising at least two or more rolling mills, the roll gap having a constant thickness of each rolling mill is set to be larger than the thickness of the inclined tip portion of the third rolling pass of the first rolling mill. During the third rolling pass of the first rolling mill, the rolling mills on the downstream side perform rolling down from the inclined portion behind the inclined tip. According to this method, the roll gaps of the second and third rolling mills disposed downstream including the first rolling mill are adjusted to each steady thickness of the rolled material and the third rolling pass of the first rolling mill. Since the rolling can be performed at a stretch by setting the thickness of the inclined front end portion, the amount of biting reduction can be further increased by reducing the pressure from the inclined portion behind the inclined front end portion. Therefore, since the tilting effect can be effectively used in the succeeding rolling mills, the rolling can be performed with a smaller number of rolls than in a normal tandem rolling mill, and the rolling line can be shortened.

According to the present invention, a rolling mill having two rolling rolls, a hydraulic rolling-down control device or an electric rolling-down control device for applying a rolling force to the rolling rolls, and an electric motor driving the rolling rolls are provided. In the first rolling pass, between the two rolling rolls in one rolling mill, the leading end of the rolled material is bitten to a predetermined thickness, and the roll gaps of the rolling rolls are sequentially opened to form an inclined leading end portion length. Perform tilt rolling under normal rotation pressure, stop at the end of tilt, bite in a predetermined thickness, and further close the roll gap of the rolling rolls, and further reduce the leading end of the rolled material in the second rolling pass. The inclined rolling to form the inclined tip portion length of such a plate thickness is performed under the reverse rolling pressure, and further, the rolling with a higher biting reduction than the normal rolling is performed under the normal rolling pressure in the third rolling pass. High pressure rolling equipment There is provided.

According to the configuration of the present invention, two rolling mills are provided.
A rolling mill having a rolling roll of the present invention, and a hydraulic rolling-down control device or an electric rolling-down control device that applies a rolling force to the rolling roll,
A motor for driving the rolling rolls, so that two forward and reverse pass rollings are performed by a hydraulic pressure reduction control device or an electric pressure reduction control device between two rolling rolls driven by a motor in one commonly used rolling mill. By applying a rolling force to the leading end of the rolled material, the inclined tip portion length can be easily formed by inclined rolling. As a result, in the third rolling pass, rolling with a higher rolling reduction than normal rolling can be easily performed. Further, since a normal rolling mill is used, the rolling mill is hardly damaged and easy to maintain. Further, since the whole rolled material does not move back and forth, the rolling line can be significantly shortened as compared with the reverse rolling.

Further, according to a preferred embodiment of the present invention, the hydraulic pressure reduction control device includes a hydraulic cylinder, a position detector for detecting a position of the hydraulic cylinder, a detector for detecting a rotation speed of a rolling roll, A computing device that predicts and calculates the rolling force based on information between passes from these detectors, a command device that outputs a rolling command calculated by the computing device, and a rolling device that operates on command output from the command device and rolls the rolls. And a hydraulic servo valve for controlling the hydraulic cylinder for applying a force.
With this configuration, feedback control of opening / closing (up / down) of the roll gap during the first and second rolling passes can be performed at a high speed, and an optimum inclined tip portion length can be formed. Rolling with higher bite reduction can be easily performed than rolling.

[0013] The electric screw-down control device includes a screw-down screw, a screw-down nut, a worm, an electric motor, a position detector for detecting a position of the screw-down screw, a detector for detecting a rotation speed of a rolling roll, An arithmetic unit that predicts and calculates the rolling force based on information between passes from these detectors, and a command unit that outputs a rolling-down command to the rolling rolls calculated by the arithmetic unit, the motor includes a command unit that outputs a command from the command unit. It operates in response to a command output to control the feed amount of the screw down which applies the rolling force to the rolling roll. Also in this configuration, it is possible to perform feedback control of opening / closing (up / down) of the roll gap in the first and second rolling passes, and to form an optimum inclined tip portion length. Rolling with a higher bite reduction can be easily performed.

Further, in the tandem rolling mill comprising at least two or more rolling mills, the roll gap having a constant thickness of each rolling mill is set to be larger than the thickness of the inclined tip portion of the third rolling pass of the first rolling mill. During the third rolling pass of the first rolling mill, the rolling mills on the downstream side perform rolling down from the inclined portion behind the inclined tip. With this configuration, the inclination effect can be effectively used in the subsequent ordinary rolling mill, so that the number of rolling operations can be reduced with a smaller number than that of the ordinary tandem rolling mill, and the rolling line can be shortened.

[0015]

Preferred embodiments of the present invention will be described below with reference to the drawings. In each of the drawings, common parts are denoted by the same reference numerals, and redundant description will be omitted.
1 to 3 show a first embodiment of a rolling equipment for performing high-pressure rolling according to the present invention. FIG. 1 is a perspective view of a rolling mill for performing high-pressure rolling according to the present invention, and FIG. 2 is a schematic side view of FIG. FIG. 3 is a partial cross-sectional view of a rolling device in inclined rolling during the second pass of the present invention.

In FIG. 1, a rolling mill 10 includes two upper and lower work rolls 11 (hereinafter referred to as “rolling rolls”).
This is a normal four-high rolling mill including upper and lower backup rolls 12 and rolling a rolled material 13 between two rolling rolls 11. In the present invention, the rolling mill is not limited to a four-high rolling mill, but may be another type of rolling mill. An axle box 14 is provided at both ends of the rolling roll 11. Similarly, an axle box 15 is provided at both shaft ends of the backup roll 12. A hydraulic pressure reduction device 17 that applies a rolling force to the rolling roll 11 is provided between the housing 16 and the lower side of the two axle boxes 15 of the upper or lower backup roll 12 (the lower in this embodiment). An electric motor 18 for rotating the roll 11 so that the roll 11 can be rotated forward and backward is attached to one shaft end of the roll 11.

In the embodiment shown in FIG.
Reference numeral 7 denotes a hydraulic cylinder, which includes a cylinder body 20 fixed to the housing 16 and an axle box 1 of the backup roll 12.
5 is connected to a piston 21 for applying a rolling force to the rolled material 13 by a pipe 24 and a hydraulic source (not shown) via a pipe port 23, while freely holding the roller 5 up and down (opening and closing the gap between the two rolling rolls 11). A hydraulic chamber 22 for supplying and discharging pressurized oil. The cylinder body 20 and the piston 21 are provided with a position detector 25 (for example, a magnescale) for detecting the position of the piston 21. The detection value detected by the position detector 25 is input to a calculation device 26 that converts the value into a rolling force. The electric motor 18 includes a detector 27 (for example, a tachogenerator) that detects the number of rotations of the rolling roll 11.
Is provided, and the detected value is input to an arithmetic unit 26 which converts the detected value into a rolling reduction force. Although not shown, the first
The inclined rolling information P1 and P2 for each of the second and second passes are also input to the arithmetic unit 26 in the same manner. A command device 28 is provided which outputs the pressure reduction command calculated by calculating these input data by the calculation device 26. Further, a hydraulic (hydraulic) servo valve 29 is provided between the hydraulic pressure source and the hydraulic pressure reducing device 17. The hydraulic servo valve 29 receives an operation signal output from the command unit 28, and Pressure oil for controlling the rolling force is supplied to or discharged from the hydraulic chamber 22.

FIG. 4 is a schematic view of the inclined rolling of the present invention showing that a reduction amount larger than a normal maximum reduction amount can be obtained. In FIG. 4A, the constant thickness of the conveyed rolled material 13 at the steady portion is set to H0, and two positive and negative values of the present invention are used.
The length of the inclined tip portion formed by reverse inclined rolling is L2, the thickness of the inclined tip portion is h2, the bite angle is θ2, the friction coefficient is μ, and the reduction amount during the third forward rolling is Δh2. Let the roll gap of the rolling roll be G0. h2 is made thinner than the above-mentioned h1 by inclined rolling.

If H0>G0> h2, then tan
Rolling is possible even when θ2> μ. Therefore, H0 -h2 =
Δh2> Δh1. As a result, if the leading end of the rolled material 13 is inclined and the outlet thickness h2 is made smaller than the roll gap G0 of the rolling roll, the biting angle can be made smaller than the friction angle of the friction coefficient and slipping can be prevented. Rolling with a high rolling reduction can be performed, and a rolling reduction larger than a normal maximum rolling reduction can be obtained. Therefore, the rolling line can be shortened.

FIG. 5 is a process chart showing the high-pressure rolling method of the present invention. The high-pressure rolling method of the present invention will be described with reference to FIGS. As shown in FIG. 5, using one rolling mill 10 and two rolling rolls 11, (a) the rolled material 13 of the steady portion H10 conveyed from the upstream is reduced under normal rotation of one rolling mill 10. The first rolling pass is started by engaging the rolling roll 11 with h11 having a predetermined tip end thickness equal to the roll gap G10. (B) Rolling material 13 is continuously rolled down by forward rolling the rolled material 13 to form a slanted tip portion length while sequentially opening a roll gap with the tip thickness h11 thinned from the steady portion H10 as a starting point. (C) At the point where the inclined line of the inclined rolling starting from the tip thickness h11 as the starting point and the parallel line of the steady portion H10 intersect (the inclined end portion), the inclined rolling of the first rolling pass is stopped. At this time, an inclined tip portion length of the length L11 is formed. (D) Next, at the end of the inclination, the rolling roll 11 is bitten to a predetermined thickness h12, and the rolling material 13 of the steady portion H10 is reversely rolled by one rolling mill 10 while sequentially closing the roll gap starting from the h12. Then, a second rolling pass, which is inclined rolling, is started so as to be thinner than the above-described tip thickness h11. (E) Rolling roll 1 by inclined rolling
When 1 reaches the leading end of the rolled material, the inclined rolling, which is the reverse rolling of the second rolling pass, is stopped. At this time, an inclined tip portion length of length L13 is formed by the thickness h13 of the tip end portion of the rolled material. (F) Next, the roll gap G13 is set to be larger than the thickness h13 of the leading end of the rolled material and smaller than the steady portion H10. (G) In this state, horizontal rolling is performed at once in the third rolling pass by normal rotation.

As described above, it is possible to perform the rolling with a higher biting reduction than the normal rolling by using three passes including the inclined rolling that forms two inclined tip portions in one ordinary rolling mill. . Therefore, there is no need to reverse the entire length of the rolled material, and the rolling line can be shortened.

FIG. 6 shows a second embodiment of the rolling equipment for performing high-pressure rolling according to the present invention, and is a partial cross-sectional view of a rolling device in inclined rolling at the time of the second pass of the present invention. The electric screw-down device 30 is configured such that the upper side of the upper and lower (upper in the present embodiment) double roll box 15 of the backup roll 12 is the housing 1.
6 is provided so as to apply a rolling force to the rolling roll 11 from the screw 32 arranged in the through hole 31. Further, the electric screw-down device 30 includes a screw nut 33 serving as a worm wheel, which is screwed to a screw provided on the outer periphery of the screw 32.
And a worm 34 that is driven by an electric motor 35 by rotating a worm screw provided on the outer periphery of the screw-down nut 33, and a position detector 36 that detects the position of the screw-down screw 32. Others are the same as FIG. Even with this electric rolling-down control, although the inclined rolling speed is slightly reduced as compared with the above-mentioned hydraulic rolling-down control, a rolling reduction larger than the normal maximum rolling reduction can be similarly obtained. Therefore, the rolling line can be shortened.

FIG. 7 shows a third embodiment of the rolling equipment for performing high-pressure rolling according to the present invention, in which three commonly used rolling mills 10, 40 and 41 are used as tandem rolling equipment and applied to the present invention. FIG. First, the leading end of the solid rolled material 13 shown by the solid line in this figure is the thickness of the leading end of the rolled material formed by two-time forward / reverse tilt rolling in the first and second embodiments. h13 is the length of the inclined tip portion having the length L13. Rolling roll 1 of rolling mill 10 in this case
One roll gap G13 is set to be larger than the thickness h13 of the leading end of the rolled material and smaller than the steady portion H10. further,
The roll gap G14 and the roll gap G15 of each of the rolling mills 40 and 41 are set in the same manner. That is, the thickness of the rolled material tip is greater than h13, the steady portion H10 and the rolling mill 1
As shown by the one-dot chain line after the rolling down at 0 and further by the two-dot chain line after the rolling by the rolling mill 40, it is set to be gradually smaller toward the downstream. In this state, the first rolling mill 10
Horizontal rolling starts in the normal rolling pass of the second rolling pass. With this configuration, as described above, since the tip portion has an inclined shape and the biting angle is made smaller than the friction angle of the friction coefficient to prevent slippage, rolling with a high biting reduction can be performed. Further, the tilting effect can be effectively used in the subsequent ordinary rolling mill, and therefore, the number of rolling can be reduced with a smaller number than that of the ordinary tandem rolling mill, and the rolling line can be shortened.

It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified without departing from the gist of the present invention.

[0025]

As described above, in the high-pressure rolling method and the rolling equipment of the present invention, a normal rolling mill is used to form an inclined shape of a predetermined length only at the leading end of a rolled material by normal / reverse rotation. In normal rolling, it prevents slippage that occurs when the bite angle exceeding the tip friction angle cannot be obtained, enabling high-bite rolling reduction, and requires a special and complicated rolling mill structure such as a planetary mill It is hard to damage, easy to maintain, and does not reverse the entire length even if the length of the rolled material is long, so the rolling line can be shortened, and even in tandem rolling mills, the number of rolling mills can be greatly reduced, And so on.

[Brief description of the drawings]

FIG. 1 is a perspective view of a rolling mill showing a first embodiment for performing high-pressure rolling according to the present invention.

FIG. 2 is a schematic side view of FIG.

FIG. 3 is a partial cross-sectional view of a rolling device in inclined rolling during a second pass of the present invention.

FIG. 4 is a schematic diagram of inclined rolling according to the present invention.

FIG. 5 is a process chart showing a high-pressure rolling method of the present invention.

FIG. 6 is a partial cross-sectional view showing a second embodiment of the rolling equipment for performing high-pressure rolling according to the present invention.

FIG. 7 is a layout view of a tandem rolling facility showing a third embodiment for performing high-pressure rolling according to the present invention.

FIG. 8 is a schematic diagram showing a relationship between a tip friction angle of a conventional rolled material and a rolling roll.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rolling machine 2 Work roll (rolling roll) 3 Rolled material 10 Rolling machine 11 Work roll 12 Backup roll 13 Rolled material 14, 15 Shaft box 16 Housing 17 Hydraulic pressure reduction device 18 Electric motor 20 Cylinder main body 21 Piston 22 Hydraulic chamber 23 Pipe opening 24 Piping 25 Position detector 26 Arithmetic unit 27 Detector 28 Commander 29 Hydraulic (hydraulic) servo valve 30 Electric screw down unit 31 Through hole 32 Screw down screw 33 Screw down nut 34 Worm 35 Electric motor 36 Position detector 40, 41 Rolling mill H0, H10 Thickness of steady part h1 Thickness after rolling Δh1, △ h2 Reduction amount θ1, θ2 Biting angle μ Friction coefficient h2, h11, h13 Tip thickness h12 Predetermined thickness L2, L11, L13 Inclined tip Part length G0, G10, G13, G14, G15 Roll gap P1, P2 Inclined rolling information

Claims (7)

[Claims] 1. A rolled material tip is bitten to a predetermined thickness in a first rolling pass between two rolling rolls in one rolling mill, and an inclined tip portion length is gradually increased while sequentially opening a roll gap of the rolling roll. Performing inclined rolling under normal rotation pressure, stopping at the end of inclination, then biting in a predetermined thickness,
While the roll gap of the rolling rolls is sequentially closed, in the second rolling pass, inclined rolling is performed under reverse rotation to form a slanted tip portion having a thickness such that the leading end of the rolled material becomes thinner, and the third rolling is performed. A high-pressure rolling method, characterized in that rolling with a higher rolling reduction than normal rolling is performed under normal rotation in a pass. 2. The thickness of the inclined front end of the third rolling pass in the one rolling mill is made thinner than the steady thickness of the rolling mill, so that the thickness behind the inclined front end during the third rolling pass is reduced. The high-pressure rolling method according to claim 1, wherein the rolling is performed from an inclined portion. 3. The roll gap having a steady thickness of each rolling mill in a tandem rolling mill comprising at least two or more rolling mills is set to be larger than the thickness of the inclined tip portion of the third rolling pass of the first rolling mill. 3. The rolling mill of the first rolling mill performs rolling down from the inclined portion behind the inclined tip end in each of the rolling mills on the downstream side during the third rolling pass.
Rolling method under high pressure. 4. A rolling mill having two rolling rolls, a hydraulic rolling-down control device or an electric rolling-down control device for applying a rolling force to the rolling rolls, and an electric motor driving the rolling rolls. In the first rolling pass between the two rolling rolls, the leading end of the rolled material is bitten to a predetermined thickness, and the rolling gap of the rolling rolls is sequentially opened to form the inclined leading end portion length. And stop at the end of the inclination, then bite in the predetermined thickness, and gradually close the roll gap of the rolling roll while gradually closing the roll gap in the second rolling pass so that the leading end of the rolled material becomes thinner. A high-pressure rolling plant, characterized in that inclined rolling for forming a tip portion length is performed under reverse rolling, and further, rolling with a higher rolling reduction than normal rolling is performed under normal rolling in a third rolling pass. . 5. The hydraulic pressure reduction control device includes a hydraulic cylinder, a position detector for detecting a position of the hydraulic cylinder, a detector for detecting a rotation speed of a rolling roll, and information between passes from these detectors. A computing device for predicting and calculating a rolling force by the command device, a command device for outputting a rolling command calculated by the computing device, and the hydraulic cylinder that is operated by a command output from the command device to apply a rolling force to a rolling roll is controlled. 5. The high-pressure rolling plant according to claim 4, comprising a hydraulic servo valve. 6. The electric screw down control device, comprising: a screw down screw;
Predictive calculation of rolling force based on information from the pass nuts, worms, electric motors, position detectors that detect the position of the screw, and the number of revolutions of the rolling roll, and information between passes from these detectors And a command device that outputs a reduction command calculated by the calculation device. The motor is operated by a command output from the command device to feed the rolling screw that applies rolling force to the rolling roll. 5. The high-pressure rolling plant according to claim 4, wherein the amount is controlled. 7. A roll gap having a constant thickness of each rolling mill in a tandem rolling mill including at least two or more rolling mills is set to be larger than a thickness of an inclined tip portion of a third rolling pass of a first rolling mill. A high-pressure rolling facility, wherein rolling is performed from the inclined portion behind the inclined front end in each of the downstream rolling mills during a third rolling pass of the first rolling mill.