JP3069101B1 - Rolling method for section steel - Google Patents

Abstract

The present invention provides a method of rolling a shaped steel capable of rolling a flange with high accuracy in consideration of the influence of a steel material and a horizontal roll between vertical rolls. SOLUTION: A rolling load value Op1 of a working side vertical roll 5 and a rolling load value Dr1 of a driving side vertical roll 6 of a universal rolling mill 1 are respectively detected, and Op2 = α · Op.
1 + β · Dr1 Dr2 = α · Dr1 + β · Op1 (where α + β = 1) and the corrected work-side rolling load value Op
2. Calculate the corrected drive-side rolling load value Dr2. The work side roll gap command value and the drive side roll gap command value are calculated based on these Op2 and Dr2, and the rolling force of the work side and drive side vertical rolls is adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for rolling symmetrical steel bars such as H-beams and I-beams.

[0002]

2. Description of the Related Art Universal rolling mills are widely used for rolling H-beams and I-beams. The universal rolling mill has a pair of upper and lower horizontal rollers and a pair of left and right working side vertical rolls and a driving side vertical roll. For example, in the case of an H-section steel, the web is rolled between the horizontal rolls. And the working-side vertical roll, and between the horizontal roll and the driving-side vertical roll.

In a universal rolling mill, the reduction of each vertical roll (hereinafter, referred to as vertical reduction) is conventionally performed by a vertical reduction by an electric motor, and a roll gap which is a gap between a horizontal roller and a vertical roller is set in advance. Rolling was performed with a constant roll gap, but hydraulic pressure reduction using a hydraulic cylinder was performed to improve dimensional accuracy,
AGC (automatic ga) with the aim of further improving product accuracy
p control) is applied to the vertical reduction control.

[0004] AGC is a method for reducing the variation in the product thickness in the longitudinal direction.
No. 22 discloses this. Generally, in the AGC, a sensor for detecting a rolling load is provided on the working-side vertical roll and the driving-side vertical roll, and based on these detection values, a gap between the horizontal roll and each vertical roll, that is, the reduction of each vertical roll, Control the force and keep the flange pressure constant. For example,
When the entry side thickness increases, the rolling load value detected by the sensor increases.Therefore, this entry side thickness variation is removed and the vertical rolling force is calculated so that the exit side thickness becomes constant. And control the hydraulic cylinder.

The vertical rolling forces by the vertical rollers on the driving side and the working side are individually applied from the hydraulic cylinders. However, the driving side rolling force and the working side rolling force are basically equal according to the law of action and reaction. When rolling a symmetrical steel such as an H-section steel or an I-section steel, the flange thicknesses of which are equal on the left and right sides, the rolling load values detected on the working side and the driving side are averaged, and the working side and the driving side are determined based on this value. The same vertical rolling force is applied to each of the vertical rollers.

[0006]

However, due to the influence of the steel material and the horizontal roll between the vertical rolls on the driving side and the working side, the detected rolling load values may not be exactly equal, and the elasticity of the steel material and the horizontal rolls may be reduced. The flange thickness may be uneven when the vertical rolling force is evenly applied due to the influence of the rate. As described above, in the above-described conventional rolling method, it is very difficult to control the thickness of the right and left flanges to be exactly the same depending on the influence of the steel material and the horizontal roller.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method of rolling a section steel capable of controlling the thickness of a flange with high accuracy and constant in consideration of the influence of a steel material between a vertical roll and a horizontal roll. .

[0008]

SUMMARY OF THE INVENTION The present invention detects a rolling load value of a working-side vertical roll and a rolling load value of a driving-side vertical roll, respectively, and based on the detected values, the rolling force of the working-side vertical roll and the driving-side vertical roll. In the method of rolling section steel by a universal rolling mill that controls the rolling force of the roll and rolls the section steel having the same thickness on the left and right flanges, the detected rolling load value of the working-side vertical roll and the rolling load value of the driving-side vertical roll are detected. Calculate the corrected working-side rolling load value and the corrected driving-side rolling load value by distributing at a preset ratio, and control the rolling force of the working-side vertical roll and the rolling force of the driving-side vertical roll based on these, respectively. The method according to claim 1, wherein the preset ratio is adjustable.

In the present invention, the detected rolling load value of the working side vertical roll is set to Op1, the rolling load value of the driving side vertical roll is set to Dr1, and the proportional distribution coefficient set in advance is α,
β, where α + β = 1, the corrected work-side rolling load value Op2 and the corrected driving-side rolling load value Dr2 are respectively calculated as Op2 = α · Op1 + β · Dr1 Dr2 = α · Dr1 + β · Op1. And

According to the present invention, the detected work-side and drive-side rolling load values are distributed at a predetermined ratio to calculate a corrected working-side rolling load value and a corrected driving-side rolling load value.
Since the vertical rolling force on the working side and the driving side is controlled based on these, even if the effect of steel or horizontal rolls between the vertical rolls appears, adjusting the distribution ratio eliminates this effect and removes the flange. The thickness can be rolled with high accuracy and constant.

Further, the rolling force of each of the vertical rolls according to the present invention is provided by an oil pressure.

According to the present invention, since the vertical rolling force is given by the hydraulic pressure, it can be controlled with high precision.

[0013]

FIG. 1 is a block diagram showing a configuration of a universal rolling mill 1 which is an embodiment using a method for rolling a section steel according to the present invention. The universal rolling mill 1 has a pair of upper and lower horizontal rollers 3 and 4, a pair of left and right working side vertical rolls 5 and a driving side vertical roll 6, and rolls the H-section steel 2. That is, the web 15 of the H-section steel 2 is rolled by the horizontal rolls 3 and 4, and one flange 16 is rolled by the horizontal rolls 3 and 4 and the working-side vertical roll 5.
The other flange 17 is rolled by 4 and the drive-side vertical roll 6.

The hydraulic cylinders 2 controlled by the control means 25 are provided at both ends of the roll shaft of the work side vertical roll 5.
0,21 are connected to provide a working side vertical rolling force. Similarly, hydraulic cylinders 22 and 23 that are controlled by the control means 25 and apply a vertical reduction force on the drive side are connected to both ends of the roll shaft of the drive-side vertical roll 6.

The work-side vertical roll 5 has a sensor 7 for detecting the rolling load on the steel material entry side (rear side on the paper surface in FIG. 1).
Further, a sensor 8 for detecting the rolling load on the delivery side (on the front side of the paper surface of FIG. 1) is provided. Similarly, the drive-side roll 6 is also provided with a sensor 9 for detecting an incoming rolling load and a sensor 10 for detecting an outgoing rolling load.

The thickness of one flange 16 of the H-section steel 2 is determined by the gap between the work-side vertical roll 5 and the horizontal rolls 3,4. The control means 25 includes a hydraulic cylinder 20,
21 is given a work-side roll gap command value which is the distance between the work-side vertical roll 5 and the horizontal rollers 3, 4, and the hydraulic cylinders 20, 21 respond to this by giving the horizontal rollers 3, 4 and the work-side vertical roll 5, , That is, the working-side vertical rolling force is adjusted. Thereby, the thickness of one flange 6 is adjusted.

Similarly, the thickness of the other flange 17 is determined by the gap between the drive-side vertical roll 6 and the horizontal rolls 3 and 4, and the control means 25 determines the distance between the drive-side vertical roll 6 and the horizontal rolls 3 and 4. Is given to the drive side hydraulic cylinders 23, 24, and the hydraulic cylinders 23, 24 adjust the gap between the drive side vertical roll 6 and the horizontal rolls 3, 4 in response to this, ie, drive Adjust the side vertical rolling force.

The control means 25 performs AGC control based on the detection values of the sensors 7 to 10. When the sensors 7 to 10 detect, for example, an increase in the vertical rolling load, that is, an increase in the flange thickness, the control means 25 determines the increase in the flange thickness based on the detected working-side rolling load value and driving-side rolling load value. The work-side roll gap command value and the drive-side roll gap command value are calculated to remove hydraulic cylinders 20, 21 and hydraulic cylinders 22, 21 respectively.
Give to 23.

The roll gap command value is calculated based on the working-side rolling load value and the driving-side rolling load value. The working-side vertical roll 5 and the driving-side vertical roll 6 are connected via the horizontal rolls 3, 4 and steel. Since the rolling loads act in opposition to each other, the rolling loads Op1 and Dr1 on the working side and the driving side are in principle equal to each other from the law of action and reaction. Value Op1,
The roll gap command value was calculated based on a value obtained by averaging Dr1.

However, in reality, the vertical rolls 5,
Rolling loads may not be exactly equal due to the effects of the horizontal rolls 3 and 4 and the steel material between the six rolls, and when controlled by the roll gap command value calculated using the average value of the rolling loads, Due to the influence of the elastic modulus of the rolls 3 and 4 and the steel material, the thickness of the flange may be uneven.

Therefore, in the present invention, the control means 25
The proportional distribution coefficients α, β (where α + β =
The rolling load value is distributed at a predetermined ratio by multiplying by 1), and the roll gap command value is calculated based on this.

FIG. 2 is a block diagram showing a control circuit of the control means 25. Based on this, the method of calculating the roll gap command value according to the present invention will be described.

First, the working-side rolling load value Op1 is obtained by adding the incoming rolling load value detected by the sensor 7 and the outgoing rolling load value detected by the sensor 8 by the adder 30. Similarly, the drive-side rolling load value Dr1 is obtained by adding the incoming rolling load value detected by the sensor 9 and the outgoing rolling load value detected by the sensor 10 by the adder 31.

Next, the working side rolling load value Op1 and the driving side rolling load value Dr1 are corrected by multiplying them by a predetermined proportional distribution coefficient α, β, and the corrected working side as a basis for calculating the roll gap command value. The rolling load value Op2 and the corrected driving-side rolling load value Dr2 are calculated using the following equations (1) and (2). Op2 = α · Op1 + β · Dr1 (1) Dr2 = α · Dr1 + β · Op1 (2)

2, the multiplier 32 multiplies the proportional distribution coefficient α by the working side rolling load value Op1 and the multiplier 34 multiplies the proportional distribution coefficient β by the driving side rolling load value Dr1. Are added by an adder 36 to calculate a corrected work-side rolling load value Op2. Similarly, the multiplier 33 multiplies the work-side rolling load value Op1 by a proportional distribution coefficient β, and the multiplier 35 multiplies the driving-side rolling load value Dr1 by a proportional distribution coefficient α. The side rolling load value Dr2 is calculated.

The proportional distribution coefficients α and β are α + β = 1
And can be set arbitrarily. For example, when the proportional distribution coefficients α and β can be set in 20 steps, when “1” is input from the input means to the control means, α = β
1/20 and β = 19/20.

When a value of 1/2 of the number of steps of the proportional distribution coefficient, that is, “10” in this embodiment, is input, α =
1/2, β = 1/2, and the corrected rolling load values Op2, D
r2 is the average value of the working-side and drive-side rolling load values, that is, Op2 = (Op1 + Dr1) / 2 Op2 = (Op1 + Dr1) / 2.

The maximum value of the input means, in this case "2
When “0” is input, α = 1, β = 0, and Op2 = Op1 Dr2 = Dr1. That is, the work-side rolling reduction control is performed based only on the detected working-side rolling load value Op1, and the driving-side rolling reduction control is performed based only on the detected driving-side rolling load value Dr1, and is independent and independent of each other. Will be controlled.

When "0" is input by the input means, α
= 0, β = 1, and Op2 = Dr1 Dr2 = Op1. That is, the work-side rolling reduction is controlled based only on the driving-side rolling load value Dr1, the driving-side rolling reduction control is controlled based only on the working-side rolling load value Op1,
Control is performed based on the rolling load value of each other.

The setting of such a proportional distribution coefficient is appropriately adjusted in advance according to the horizontal rolls 3, 4 used, the steel material or the flange thickness of the product, and is set in advance. Further, the adjustment of the proportional distribution coefficient is not limited to adjustment in a stepwise manner, and may be performed in a stepless manner.

When the corrected work-side rolling load value Op2 is calculated, the working-side roll gap command value is calculated by the roll gap command value calculator 38. Similarly, when the corrected drive-side rolling load value Dr2 is calculated, The drive-side roll gap command value is calculated by the roll gap command value calculator 39.

The roll gap command value is calculated according to BISRA
It is calculated by a method similar to the method used in AGC.
The BISRA AGC detects a change in rolling load caused by a change in sheet thickness, and calculates a roll gap command value required to return the change in sheet thickness to 0 based on the detected change. For this purpose, the spring constant of the universal rolling mill is measured in advance, and the difference between the predetermined lock-on load value and the detected rolling load value, and the roll gap value that eliminates the effect of the change in sheet thickness based on the spring constant of the rolling mill, are calculated. calculate. The lock-on load value is a reference rolling load value, and is, for example, a load when a predetermined time elapses after the steel material is engaged in the roll and the fluctuation of the load is stabilized.

Therefore, in the present invention, the work-side roll gap command value is calculated based on the difference between the corrected work-side rolling load value Op2 and the lock-on load value, and the spring constant of the rolling mill 1 measured in advance. Similarly, the drive-side roll gap command value is calculated based on the difference between the corrected drive-side rolling load value Dr2 and the lock-on load value, and the spring constant of the rolling mill 1.

The work side roll gap value calculated in this way is equal to the work side vertical roll hydraulic cylinders 20,2.
1, the rolling force of the working-side vertical roller 5 is adjusted, and a change in the thickness of one flange 6 is removed. Similarly, the drive-side roll gap value is given to the hydraulic cylinders 22 and 23 of the drive-side vertical roll, the rolling force of the drive-side vertical roll 6 is adjusted, and the change in the thickness of the other flange 7 is removed. Thus, the H-section steel 2 can be rolled with high precision.

In the present embodiment, the section steel is an H section steel. However, the present invention is not limited to this, and the invention can be applied to any section steel such as an I section steel having the same flange thickness on the left and right.

Further, in the present embodiment, the detected rolling load values are distributed as in the above-described equations (1) and (2). However, the method of distributing the detected rolling load values Op1 and Dr1 is not limited to the above-described method. Alternatively, the distribution may be made such that, for example, Op2 = α · (Op1 + Dr1) Dr2 = β · (Op1 + Dr1). Here, α + β = 1. Another distribution method may be used.

The rolling mill 1 of the present invention may be used in a rough rolling step or a finishing step.

[0038]

As described above, according to the present invention, the detected working-side and drive-side rolling load values are distributed at a predetermined ratio, and the working-side and drive-side vertical rolling forces are controlled based on these. Therefore, even if there is a detection error in the vertical rolling force on the driving side and the working side due to the effect of the steel material between the vertical rolls and the horizontal roll, this effect can be removed and the flange of the section steel can be rolled with high precision .

Since the set distribution ratio can be adjusted, it can be adjusted as appropriate according to the horizontal roller used, the steel material to be rolled, and the like.

Further, it is possible to control with high accuracy by applying the vertical rolling force by hydraulic pressure.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a universal rolling mill 1 using a rolling control method for a shaped steel according to the present invention.

FIG. 2 is a block diagram showing a control circuit of a control means 25.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Universal rolling mill 2 H-section steel 3,4 Horizontal roll 5 Work side vertical roll 6 Drive side vertical roll 7-10 Sensor 25 Control means

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Keio Saka 3-1-1 Higashi Kawasaki-cho, Chuo-ku, Kobe-shi, Hyogo Kawasaki Heavy Industries, Ltd. Kobe Plant (56) References JP-A-63-123510 (JP, A) Japanese Patent Publication No. 63-66608 (JP, B2) Japanese Patent Publication No. 6-55325 (JP, B2) (58) Field surveyed (Int. Cl. ⁷ , DB name) B21B 37/16-37/22

Claims (3)

(57) [Claims] 1. A rolling load value of a working-side vertical roll and a rolling load value of a driving-side vertical roll are detected, and a rolling force of the working-side vertical roll and a rolling force of the driving-side vertical roll are controlled based on the detected values. In a method for rolling a section steel by a universal rolling mill that rolls a section steel having the same thickness on the left and right flanges, the detected rolling load value of the working-side vertical roll and the detected rolling load value of the driving-side vertical roll are distributed at a preset ratio. To calculate the corrected working-side rolling load value and the corrected driving-side rolling load value, and based on these, control the rolling force of the working-side vertical roll and the rolling force of the driving-side vertical roll, respectively, and adjust the preset ratio. A method for rolling shaped steel, which is possible. 2. The detected rolling load value of the working side vertical roll is Op1, and the detected rolling load value of the driving side vertical roll is Dr1.
And the preset proportional distribution coefficient is α, β, where α
When + β = 1, the corrected work-side rolling load value Op2 and the corrected driving-side rolling load value Dr2 are respectively calculated as Op2 = α · Op1 + β · Dr1 Dr2 = α · Dr1 + β · Op1. 2. The method for rolling a shaped steel according to item 1. 3. The method according to claim 1, wherein the rolling force of each of the vertical rolls is given by an oil pressure.