JPH08309416A - Method for controlling flange width of wide flange shape and device therefor - Google Patents

Abstract

PURPOSE: To acculately control flange width by using the output of a load cell for rolling load of a edger mill and the output of a screw-down location detecting device in the calculation of gage-meter flange width and using a flange edging load in predictive calculation of the return amount of the flange width in a universal mill of the poststage. CONSTITUTION: At the time of rolling a wide flange shape 3 with the edger mill 1 and universal mill 2, the flange edging load is calculated from the output of the load cell 8 for rolling load of the edger mill. The gage-meter flange width is calculated from the output of the load cell 8 for rolling load of the edger mill and output of edger roll position detector 7 and, further, the width return amount generated in the universal mill 2 of the poststage is calculated from the calculated flange edging load. The flange width after rolling by the succeeding universal mill is predicted and calculated as the sum of the gage- meter flange width and the width return amount and the gap between the edger rolls is continuously controlled in accordance with its deviation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flange width control method and apparatus for rolling H-section steel.

[0002]

2. Description of the Related Art H-section steel is first roughly rolled by a roll having a caliber shape, and then this rolled material is a set of one or two rolling mills composed of a rough universal rolling mill and an edger rolling mill. Rolling is performed by rolling multiple passes in. That is, in the rough universal rolling mill, the material to be rolled is rolled by horizontal rolls and vertical rolls, and the flange thickness and web thickness of the material to be rolled are reduced to bring it closer to the specified product thickness. With the roll, the toes of the flange of the material to be rolled are pressed down to finish to a prescribed flange width. Then, the material to be rolled that has passed through the group of rough rolling mills is finally finished by a finishing universal rolling mill composed of horizontal rolls and vertical rolls so as to have a target dimension.

The H-section steel thus produced must be rolled such that the web height, web thickness, flange thickness and flange width are within the specified tolerances. However, among these dimensions, the adjustment of the flange width is the most difficult and the fluctuations are large, and the problem in particular is the fluctuation of the flange width over the entire length.

Now, considering a case where the material to be rolled is subjected to two-pass rolling of, for example, a universal rolling mill → an edger rolling mill → a universal rolling mill, the flange width is rolled by the edger rolling mill as described above. Due to the edging, dog bones are generated at the toes of the flange in proportion to the amount of edging. After the edger rolling, when the rolling is performed again by the universal rolling mill, the flange width is widened (width return) depending on the dog bone amount.

Regarding the flange width control method for making the flange width of the H-section steel uniform in the longitudinal direction, there are the following patents. That is, in a tandem rolling mill composed of an edger rolling mill and a main rolling mill, the sum signal of a signal proportional to the output of the thermometer on the inlet side of the edger rolling mill and a signal proportional to the output of the width gauge on the outlet side of the main rolling mill is used for edger rolling positioning An edger rolling mill control device (eg, JP-B-55-55) for controlling the reduction position as an input signal of the device and for correcting the output torque of the roll driving motor in inverse proportion to the output of the thermometer so as to correct the rotation speed of the motor. 16725) or H-section steel in a multi-pass rolling with a rolling mill train including a universal rolling mill and an edger rolling mill, the flange width is measured in front of the edger rolling mill, and the rolling of the edger rolling mill and the universal rolling mill is performed. Calculate the resulting flange width expansion using a model formula, and set the edge width so that the flange width after the next pass universal rolling will be the target value. Flange width control method of the H-beams to adjust the over mill opening continuously (JP 59-166
11).

On the other hand, in the strip width control in the strip rolling, the gauge meter strip width is calculated from the edger rolling mill rolling load and the edger rolling position detection device, and the strip width is expanded from the edger rolling mill rolling load in the subsequent horizontal rolling mill. Estimate and calculate the strip width after the second stage horizontal rolling as the sum of the gauge meter strip width and strip width spread, and continuously control the edger rolling position according to the deviation so that the strip width in the longitudinal direction. A method of making the temperature uniform is often used.

[0007]

The use of a signal proportional to the output of the width gauge on the output side of the rolling mill as an input signal of the edger rolling position determining device is equivalent to the time required to transfer the steel material between the edger rolling mill and the width gauge. Due to the time delay, there arise problems that the response of the control is deteriorated and unstable.

In order to use a signal proportional to the output of the thermometer on the rolling mill input side as the input signal of the edger pressure-reducing positioning device, it is necessary to perform phase matching processing of the thermometer output and the pressure-reducing positioning device input signal. It is difficult to realize strict phase matching, and a slight phase matching error occurs, which hinders improvement in control accuracy.

In general, the environment immediately near the rolling mill is extremely bad due to water, dust, etc., so that it is often difficult to perform highly accurate measurement with a width meter or a thermometer. For this reason, the width meter and the thermometer are often installed at a position several meters to several tens of meters away from the rolling mill. In such a case, the time delay increases and the phase matching accuracy further deteriorates. To do.

Although the above-mentioned problems of phase alignment and time delay can be solved by using the method for controlling the strip width in rolling the steel sheet for controlling the flange width of the H-section steel, the edger rolling of the H-section steel can reduce the rolling load of the edger rolling machine. Since the web touch load component described later, which is not directly related to the flange width return amount in the latter-stage universal rolling mill, is included, accurate control cannot be performed.

The present invention provides a flange width control method for a shaped steel for continuously controlling an edger roll gap, focusing on the fact that the edger roll reaction force and the flange width return amount in finish rolling have a constant relationship. .

[0012]

The gist of the present invention is as follows. (1) When rolling the H-section steel with an edger rolling mill and a universal rolling mill, the flange width reduction load is calculated from the output of the edger rolling mill rolling load cell, and the output of the edger rolling mill rolling load cell and the edger roll position are calculated. The gauge meter flange width is calculated from the output of the detector, and the width return amount generated in the latter stage universal rolling mill is calculated from the calculated flange width reduction load, and the latter stage universal rolling is calculated as the sum of the gauge meter flange width and the width return amount. A flange width control method for H-section steel, which comprises predicting and calculating the subsequent flange width and continuously controlling the edger roll gap according to the deviation.

(2) A rolling load detector, a web touch load detector and a rolling position detector are provided in the edger rolling mill installed in the preceding stage of the H-shaped steel universal rolling mill, and the rolling load detector output and the rolling position are provided. A gauge meter flange width deviation calculation device that calculates a gauge meter flange width deviation from the detector output, and a load separation calculation device that calculates a flange reduction load from the rolling load detector output and the web touch load detector output, A width return amount deviation calculation device for calculating a deviation of a flange width return amount in the subsequent universal rolling mill from the calculation device output, and a flange for calculating a flange width deviation from the calculation device output and the gauge meter flange width deviation calculation device output A width deviation calculation device,
A flange width control device for H-section steel, comprising: a feedback calculation device that calculates a target position of the reduction device from the calculation device output; and a reduction control device that controls the position of the reduction device according to the calculation device output. .

[0014]

The operation of the present invention will be described below with reference to an example of a rolling apparatus capable of separating the output of the edge loader rolling load meter into the flange width reduction load and the load due to the contact of the web rolls (hereinafter referred to as the web touch load).

At a certain time, the edger rolling load P
Is input, the rolling load separation device separates P into a flange width reduction load Pf and a web touch load Pw.
Next, a deviation ΔP from the lock-on value of the edger rolling load P, a deviation ΔPf from the lock-on value of the flange width reduction load Pf, and a deviation ΔS from the lock-on value of the reduction position are calculated. From these, the deviation ΔF = ΔP / M + ΔS from the lock-on value of the gauge meter flange width is calculated.

On the other hand, there is a proportional relationship Fu = η × F0 × Pf (where F0: average flange width after edger rolling) between the flange width reduction load Pf and the width return amount Fu in the latter-stage universal rolling mill. , The deviation ΔF of the width return amount from the lock-on value
u is estimated to be ΔFu = η × F0 × ΔPf, and the reduction position change amount required to set this to 0 is X2 = η × F0 ×
It is calculated as ΔPf / (η × P + 1). The total deviation of the deviation of the gauge meter flange width and the deviation of the width return amount is 0
The amount of reduction position change required to obtain is X3 = ΔF + X2 = α × ΔP / M + ΔS + β × η × F0
× ΔPf / (η × P + 1) where α is the tuning factor for the gauge meter flange width deviation, β is the tuning factor for the width return amount deviation, and K (ΔS-X3) = K (α × ΔP for the reduction device. / M + β × η × F0 ×
A position command of ΔPf / (η × P + 1)) is input. Here, K is a feedback control gain, and various general-purpose ones such as proportional control, integral control, and proportional integral control can be used.

That is, in edger rolling of shaped steel, when the web center deviation of the rolled material is large, the web touch roll portion that restrains the web comes into contact with the web and the load caused by changing the root of the web, and the web touch roll gap against the web. When the thickness is thick, so-called web touch load occurs due to the web touch roll part rolling down the web, and the edger rolling load detector detects the sum of the flange width rolling down load and the web touch load. Since only the flange width reduction load is directly related to the flange width return amount in the rolling mill, the web touch load becomes noise in the flange width return amount prediction, and the flange width return amount in the subsequent universal rolling mill can be accurately estimated. Therefore, the problem that accurate control cannot be performed has been resolved.

When edging by the amount of edging ΔE in edger rolling, bulging is generated at the flange tip as shown in FIG. 3, and a part of this bulging extends in the flange width direction by finish universal rolling.
Although the flange width return of ΔH occurs, the present inventors have confirmed that the edging amount ΔE and the width return amount ΔH are in a proportional relationship as shown in FIG. 4A.

Further, as estimated from the generally known relationship that the edging amount ΔE is proportional to the flanger rolling reduction Pf of the edger rolling mill, the flange rolling reduction Pf of the edger rolling mill and the width return amount ΔH are estimated. The present inventors have also confirmed that there is a proportional relationship as shown in FIG.

As a result of the above processing, in the uncontrolled rolling, the edger roll gap can be closed in the large flange width portion and the roll gap can be opened in the small width portion. It can be reduced compared to uncontrolled rolling.

[0021]

1 is a control block diagram of the present invention. The present invention is provided with a rolling device capable of separating the output of the edge loader rolling load meter into the flange width reduction load and the load due to the contact of the web rolls when rolling the H-section steel 3 by the edger rolling mill 1 and the universal rolling mill 2. , Load separation computing device 6
Calculate the flange width reduction load by. Further, the gauge meter flange width 10 is calculated from the output of the edge loader rolling load meter 8 and the output of the edger roll position detector 7,
Furthermore, the width return amount 11 generated in the latter-stage universal rolling mill is calculated from the separately detected flange width reduction load, and the flange width after the second-stage universal rolling is predicted and calculated 12 as the sum of the gauge meter flange width 10 and the width return amount 11. The flange width is made uniform in the longitudinal direction on the exit side of the universal rolling mill by continuously controlling the edger roll gap by the feedback calculation device 13 and the rolling-down control device 5 according to the deviation. FIG. 2 is a flowchart of the control of the present invention.

According to the present inventors, as a result of the finishing mill width return characteristic investigation, it was found that the width return rate can be estimated from the flange reduction load of the edger mill. On the other hand, in an edger mill, light web touch rolling is usually performed in order to prevent web deviation, and not only flange reduction but also web load is applied to the rolling mill. However, the reaction force measuring method using the load cell installed in the screw mutter can detect only the sum of the flange rolling load and the web touch reaction force (see FIG. 6).

On the other hand, in order to estimate the width return rate with high accuracy, it is essential to detect only the flange reduction load, that is, separate detection of the flange reduction load and the web touch reaction force.

The applicant has previously proposed an eccentric ring type edger in Japanese Patent Publication No. 5-32128, but according to the present invention, in rolling using this eccentric ring type edger roll, a flange rolling load is applied. The separation detection of the web touch reaction force is easy with the method shown in FIG.

That is, when the eccentric ring type edger roll makes a web touch, the web touch roll tends to escape in the direction in which the caliber depth becomes shallow due to the web touch reaction force. At this time, since torque is applied to the eccentric drive hydraulic motor that supports the web touch roll, a hydraulic pressure difference (= differential pressure) occurs between the primary side and the secondary side of the hydraulic motor. This differential pressure has a certain relationship with the web touch reaction force. Therefore,
The web touch reaction force can be estimated independently by measuring the differential pressure.

FIG. 6 shows the details. That is, in the eccentric ring type edger roll, the eccentric ring 66 is rotatably fitted to the outer circumference of the flange pressing roll 62 via the bearing 64, and the bearing is concentric with the eccentric ring on the outer circumference of the eccentric ring. The web touch roll 63 is rotatably fitted in the structure via 64.

The eccentric ring 66 is used for the flange reduction roll 6
2 has a structure in which a ring portion whose axis is eccentric by ε and a gear portion which is concentric with the flange pressing roll 62 are integrated. The eccentric ring gear portion is connected to an eccentric drive gear 68 fixed to a roll chock, a housing, or the like. By rotating an eccentric drive hydraulic motor 69 directly connected to the eccentric drive gear 68, the eccentric drive gear 68 is rotated. It is possible to change the eccentric angle θ, and by stopping the eccentric drive hydraulic motor 69, the eccentric ring 66 can be fixed and supported. The eccentric drive hydraulic motor 69 rotates by opening the flow rate adjusting valve and feeding in hydraulic fluid, and stops when the flow rate adjusting valve is closed.

In the eccentric drive hydraulic motor, the inlet and outlet hydraulic pressures are constant if the load torque is constant. When a web touch (steel material web portion comes into contact with a web touch roll) and its web touch load is Pw, the torque Tw = Pw × ε COSθ with the moment ε COSθ about the flange rolling roll axis Co is biased. It will be added to the core ring (the figure is for the case of the eccentric angle θ = 0).

This torque Tw is transmitted as a load torque increment to the eccentric drive hydraulic motor shaft through the eccentric drive gear, and one side of the eccentric drive hydraulic motor inlet side and the other side of the outlet side pressure increases, and the other one. It decreases, that is, the differential pressure increases.

Since the differential pressure increase margin pm is proportional to the load torque increment Tw, the following relationship is obtained: pm = α × Tw = α × Pw × ε COSθ (α: proportional constant). Here, ε is known as a mechanical constant, and the eccentricity angle θ can always be detected as θ = i × φ (i: gear ratio) from the output φ of the angle detector directly connected to the eccentric drive gear shaft. Therefore, the web touch load Pw
Can be estimated from the differential pressure increase margin pm as Pw = pm / {α × ε COSθ (i × φ)}.

FIG. 7 shows the results when the flange width control method of the present invention was carried out and when the width was not controlled. In the method of the present invention, the fluctuation width of the flange in the longitudinal direction is smaller than that in the conventional example. Although the present invention has been described above with respect to the method of separately calculating the flange width reduction load and the web touch load in the eccentric ring type edger roll, the present invention is not limited to this. Also,
It is needless to say that the present invention can be applied not only to the edger rolling machine before the finishing universal rolling machine but also to the flange width control in the rough universal rolling machine and the edger rolling machine in the rough rolling machine group.

[0032]

The present invention is equipped with a rolling device capable of separating the output of the edge loader rolling load meter into the flange width reduction load, the web and the web touch load, and in the gauge meter flange width calculation, the edger rolling mill output force output. The flange width can be accurately controlled by using the flange width reduction load in the prediction calculation of the flange width return amount in the post-stage universal rolling mill by using the output of the and the rolling position detection device.

[Brief description of drawings]

FIG. 1 is a control block diagram of the present invention.

FIG. 2 is a flowchart of the present invention.

FIG. 3 is an explanatory view of the operation of the present invention.

FIG. 4A is a diagram showing a relationship between a width return amount and an edging amount, and FIG. 4B is a diagram showing a relationship between a width return amount and a flange rolling load.

FIG. 5 is an explanatory diagram of reaction force separation detection according to the embodiment of the present invention.

6A and 6B are explanatory diagrams of conventional edger roll load detection.

FIG. 7 is a graph showing the relationship between the H-shaped steel longitudinal direction and the flange width.

[Explanation of symbols]

 1 Edger rolling mill 2 Universal rolling mill 4 Rolling down device 6 Load separation computing device 7 Rolling down position detector 10 Gauge meter Flange width deviation computing device 12 Flange width deviation computing device

Front page continued (72) Inventor Kenichi Saiki No. 1 Tsukiko Hachimancho, Sakai City Inside Nippon Steel Co., Ltd. (72) Inventor Shunsuke Yamamoto No. 1 Tsukiko Hachimancho Sakai City, Nippon Steel Inside the Sakai Steel Works

Claims (2)

[Claims] 1. When rolling H-section steel with an edger rolling mill and a universal rolling mill, a flange width reduction load is calculated from the output of the edger rolling mill load meter, and the output of the edger rolling mill load meter and the edger The gauge meter flange width is calculated from the output of the roll position detector, and the width return amount generated in the subsequent stage universal rolling mill is calculated from the calculated flange width reduction load, and as the sum of the gauge meter flange width and the width return amount. A flange width control method for H-section steel, comprising predictively calculating the flange width after the second-stage universal rolling and continuously controlling the edger roll gap according to the deviation. 2. A rolling load detector, a web touch load detector and a rolling position detector are provided in an edger rolling mill installed in the preceding stage of the H-shaped steel universal rolling mill,
A gauge meter flange width deviation calculation device that calculates a gauge meter flange width deviation from the rolling load detector output and the reduction position detector output, and a flange reduction load from the rolling load detector output and the web touch load detector output. A load separation calculating device, a width returning amount deviation calculating device for calculating a deviation of the flange width returning amount in the latter stage universal rolling mill from the calculating device output, the calculating device output and the gauge meter flange width deviation calculating device output A flange width deviation calculating device for calculating a flange width deviation from the following, a feedback calculating device for calculating a target position of the pressure reducing device from the output of the calculating device, and a reduction control device for controlling the position of the pressure reducing device according to the output of the calculating device. A flange width control device for H-section steel, characterized by being provided.