JP3355919B2 - Method and apparatus for rolling H-section steel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for rolling an H-section steel, and more particularly to a technique for making the thickness of four flanges uniform.

[0002]

2. Description of the Related Art A conventional hot rolling process for an H-section steel is schematically shown in FIG. A raw material such as a slab, a bloom or a beam blank heated to a predetermined temperature in the heating furnace 1 is rolled into a crude steel slab by a breakdown rolling mill 2, and then at least one or more universal rolling mills 3,
Rolled to a predetermined size by a group of coarse universal rolling mills consisting of (3 ′) and edger rolling mills 4 and (4 ′),
Finally, it is rolled to a finished shape by a finishing universal rolling mill 5.

[0003] In the breakdown rolling, a crude steel slab is rolled by a plurality of dies 12 as shown in FIG. 9, but the setting position of the centering guide of the material to be rolled, the rolling bite posture or the shape of the dies and the pass schedule are not correct. It is difficult to always obtain a desired crude steel slab which is symmetrical due to proper or backlash, and the coarse slab having a non-uniform cross-sectional shape is not supported on the final product after universal rolling. This is a factor that lowers the dimensional accuracy such as the thickness at various places.

In the group of rough universal rolling mills,
With a universal rolling mill having a pair of horizontal rolls and a pair of vertical rolls, the web is separated by 4 between the horizontal roll pairs.
The flanges at the two locations are reduced in the thickness direction by the gap between the horizontal roll and the vertical roll, and the width of the right and left flanges is reduced by an edger rolling mill. These rolling operations are repeated until the rolls have a predetermined size. In rolling in the universal rolling mill group, various rolling factors affect the deformation of the web and the four flanges, and the deformations affect each other, so that the thickness of the four flanges is particularly uniform. It is difficult to reduce the uneven thickness of the flange.

[0005] The first reason why it is difficult to make the flange thickness uniform is that when the sectional shape of the crude steel slab after the breakdown rolling is not symmetrical in the vertical and horizontal directions as shown in FIG. Even if the gap is appropriately set and the four gaps between the horizontal roll and the vertical roll are all set equal to each other and rolled, the thickness of each part corresponding to the flange of the crude steel slab to be rolled is different. Each rolling reaction force is different, and as shown in FIG. 11, the difference in the rolling reaction force includes play, and not only the elastically supported vertical rolls but also the horizontal rolls are displaced in the roll axis direction. The thickness of each part of the flange is not uniform. In other words, in order to make the flange thickness uniform, accurately grasp the axial characteristics of the horizontal roll, accurately predict the rolling reaction force acting on each flange, and set the axial position of the horizontal roll appropriately. And it has conventionally been difficult to implement this. Also, as a second reason, even when the cross-sectional shape of the crude steel slab after the breakdown rolling is good and symmetrical in the vertical and horizontal directions, before the rolling in the universal rolling, the horizontal roll pair and the vertical roll pair are previously set to a desired interval. Set with high accuracy,
And it is very difficult to confirm it at present because there is no rolling mill play and no effective roll gap detector, and if the roll gap of one pass is inappropriate, the material to be rolled will not be able to be used after the next pass rolling after the next pass. As a result, as described above, the dimensional accuracy of the final product is reduced.

Various studies have been made on the dimensional control in the rolling of H-section steels.
Japanese Patent Application Laid-Open No. 23510 discloses an apparatus which can control the average size of four flanges.
If the thickness is uneven, the horizontal roll is displaced in the axial direction for the above-mentioned reason, and it is impossible to remove uneven thickness of the flange.

As a technique for making the thickness of four flanges uniform, there is a technique disclosed in JP-A-6-15327. Although this technique is effective in reducing the unevenness of the thickness of the four flanges, there is no means for detecting the rolling reaction force acting in the axial direction of the horizontal roll. The plastic properties of flange rolling of the material cannot be accurately grasped from the actual rolling results, making it difficult to accurately set the axial position of the horizontal roll to correct uneven flange thickness. There is a disadvantage that it cannot be removed.

As described above, in the prior art, since there is no device for detecting the rolling reaction force acting in the axial direction of the horizontal roll, it is possible to efficiently and stably realize the uniformity of the thickness of the four flanges. There was a problem that it was difficult.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a method of rolling an H-section steel capable of more efficiently and stably removing unevenness in the thickness of four flanges generated in universal rolling of an H-section steel, and a method thereof. It is intended to provide a device.

[0010]

According to the present invention, there is provided an apparatus for setting a rolled material which has been shaped and rolled, in addition to a roll-down position setting device for horizontal and vertical rolls, and a device for setting an axial position of horizontal rolls. Rolling is performed by a universal rolling mill equipped with a device for detecting a rolling load acting on the right and left vertical rolls and a device for detecting a rolling reaction force acting in the axial direction of the upper and lower horizontal rolls in addition to a device for detecting the rolling load acting on the left and right vertical rolls. By a hot dimension meter close to the universal rolling mill, at least the web thickness and the flange thickness and the flange width at four locations were measured, and from the dimension measurement results, the rolling loads and the rolling reaction force, the universal rolling mill characteristics in the pass were determined. The plastic properties of the four webs and flanges are calculated by an arithmetic unit, and the following rolling position schedules are performed based on these latest rolling mill characteristics and plastic characteristics. By modifying the apparatus,
This makes it possible to efficiently and stably remove unevenness in the thickness of four flanges. That is, H according to the present invention
The method of rolling section steel is as follows: in the universal rolling of the material to be rolled, measure at least the web thickness of the material to be rolled, the flange thickness and the flange width at four locations, and roll the upper and lower horizontal rolls and the left and right vertical rolls of the universal rolling mill. Detecting the load and detecting the rolling reaction force acting in the axial direction of the horizontal roll, the measurement result of the material to be rolled, the rolling load of the horizontal roll and the vertical roll, and the rolling reaction force of the horizontal roll in the axial direction, Calculate the characteristics of the universal rolling mill and the plastic properties of the material to be rolled, modify the pass schedule of the material to be rolled based on the calculation result, and set the rolling position of the horizontal roll and vertical roll and the axial position of the horizontal roll. It is characterized by the following.

In the case where the material to be rolled is rolled by a rolling mill row comprising at least one universal rolling mill and at least one edger rolling mill, the rolling position of the upper and lower horizontal rolls of the edger rolling mill is also corrected. And set.

[0012] The rolling device for H-section steel according to the present invention comprises a rolling position setting device and a rolling load detecting device installed on each of the upper and lower horizontal rolls and the left and right vertical rolls, and an axis for setting the axial position of the horizontal roll. A universal rolling mill having a direction position setting device and a rolling reaction force detecting device that detects a rolling reaction force acting in the axial direction, and is installed at a position close to the universal rolling mill, and has at least four web thicknesses of the material to be rolled at four locations. The dimensions of the universal rolling mill and the rolled capacity are measured from the dimension gauge for measuring the flange thickness and flange width, the measurement results of the dimension gauge, the rolling load of the horizontal roll and the vertical roll, and the axial rolling reaction force of the horizontal roll. A first arithmetic unit for calculating the plastic characteristic of the material, and correcting the pass schedule of the material to be rolled based on the calculation result, and applying pressures of the horizontal roll and the vertical roll. It is characterized in that the axial position of the horizontal roll and a second arithmetic unit for setting and operation.

[0013] Further, the rolling apparatus of the present invention comprises at least one
A rolling mill row comprising at least one universal rolling mill and at least one edger rolling mill, wherein the second arithmetic unit further calculates and sets the rolling position of the upper and lower horizontal rolls of the edger rolling mill. It was done.

First, the configuration of the rolling apparatus of the present invention and the deformation characteristics of the material to be rolled will be described. FIG. 1 shows a basic configuration of a rolling device of the present invention.
A universal rolling mill 9 and a hot dimension meter 16 installed at a position close to the rolling mill 9 for measuring at least the web thickness of the material to be rolled 15 and the flange thickness and flange width at four locations.
And the upper and lower horizontal rolls 13a, 1 of the universal rolling mill 9.
3b and the roll-down position setting devices 22a, 22b, 2 for setting the roll-down positions of the right and left vertical rolls 14a, 14b.
3a, 23b and rolling load detecting devices 20a, 20b, 21a, 21b for detecting the rolling load acting on each roll
And rolling reaction force detecting devices 19a and 19b for detecting a rolling reaction force acting in the axial direction of the horizontal rolls 13a and 13b, and axial position setting devices 24a and 24 for setting an axial position.
b, the measurement result of the hot dimension meter 16 and the horizontal rolls 13a,
A first arithmetic unit 17 for calculating rolling mill characteristics and plastic characteristics of the material 15 to be rolled from the rolling loads of the vertical rolls 13b and the vertical rolls 14a and 14b and the axial reaction forces of the horizontal rolls 13a and 13b; And a second calculating device 18 for correcting the pass schedule of the material 15 to be rolled on the basis of the above and calculating and setting the rolling position of each roll and the axial position of the horizontal rolls 13a and 13b.

FIG. 1 shows a situation where the material to be rolled 15 is rolled by the universal rolling mill 9 and the web thickness, the flange thickness and the flange width at four locations are measured by the adjacent hot dimension gauge 16. And horizontal rolls 13a and 13b and vertical rolls 14a and 14b during rolling.
The rolling load acting on the horizontal roll rolling load detector 20
a, 20b and vertical roll rolling load detecting device 21a, 2
1b, the horizontal rolls 13a, 13
The rolling reaction force acting in the axial direction of b is detected by a rolling reaction force detecting device 19.
a, 19b.

In the universal rolling mill, as shown in FIG. 11, the web is formed at the gap between the upper and lower horizontal rolls 13a and 13b, and the web is formed at the four gaps formed by the upper and lower horizontal rolls 13a and 13b and the left and right vertical rolls 14a and 14b. Is rolled, each roll is elastically displaced by a rolling reaction force generated at each portion at this time. Further, when the offset amount of the center of the roll gap formed by the horizontal roll pair is represented by P _L with respect to the center in the body length direction of the vertical roll, the relationship between the roll gap and the rolling reaction force is, for example, Can be expressed as follows.

T _w2 = S _H + P _H / K _H + δ _H + δ _W P _VD = P _F1 + P _F2 P _VF = P _F3 + P _F4 t _F21 = R _VD + P _VD / K _VD + R _HU + (P _F1 −P _F3 ) / K _HTU + δ _VD + δ _HTU + δ _F1 −P _L tan θ t _F22 = R _VD + P _VD / K _VD + R _HL + (P _F2 −P _F4 ) / K _HTL + δ _VD + δ _HTL + δ _F2 + P _L tan θ _{t F23 = R VF + P VF} / K VF -R HU - (P F1 -P F3) / K HTU + δ VF -δ HTU + δ F3 -P L tan θ t F24 = R VF + P VF / K VF -R HL _{- (P F2 -P F4) /} K HTL + δ VF -δ HTL + δ F4 + P L tan θ ... (1) t wi; i = 1; web thickness before rolling, i = 2; web thickness after rolling t _fij; i = 1; pre-rolling of the flange thickness, i = 2; flange thickness after rolling, j; 1 to 4, flange position [delta] _H; reduction of the horizontal roll direction backlash [delta] _HTU; axial backlash of the upper horizontal roll [delta] _HTL: lower horizontal Axial play S _H of Lumpur; unloaded horizontal roll set gap K _H; spring constant in the horizontal roll rolling direction support system P _H; rolling reaction force acting on the horizontal roll P _VD; drive side vertical roll rolling load P _VF Free side vertical roll rolling load P _Fj ; Flange roll reaction force j; 1-4, Flange position δ _Vl ; Vertical roll play l; D, F, Drive side or free side vertical roll δ _W ; Horizontal roll pressure down roll Gap variation (roll wear, thermal expansion, etc.) δ _Fj ; Flange position j equivalent roll gap variation (roll wear, thermal expansion, etc.) R _Vl ; Vertical roll setting position l; D, F, drive side or free side vertical roll K _Vl; spring constant of the vertical roll support system l; D, F, the drive side or the free side perpendicular roll R _HU; upper horizontal roll axis direction setting position R _HL; lower horizontal roll axis direction setting position K _HTU; The spring constant of the horizontal roll axis direction support system K _HTL; spring constant of the lower horizontal roll axis direction support system theta; roll surface angle

The spring constant of each roll support system in the above formula (1) is previously measured and known, and changes during rolling are small. On the other hand, even if the play is measured in advance, the apparent change is caused by fluctuations (δ _W , δ _{Fj in} equation (1)) such as roll wear and roll thermal expansion during rolling.
It is very important to always grasp these accurately in order to improve the dimensional accuracy of the material to be rolled, particularly the accuracy of the flange thickness at four locations. With the conventional universal rolling mill and a hot dimension meter close to the conventional rolling mill, the respective thicknesses in the formula (1) and the rolling loads acting on the horizontal roll and the vertical roll are known, but in the prior art, the axial direction of the horizontal roll is changed. The acting rolling reaction force ((P _F1 -F _F3 ) or (P _F2 -P
_{Since F4} )) cannot be detected, it is impossible to exactly grasp each play and the variation during rolling (δ _W , δ _{Fj in} equation (1)).

The first major feature of the present invention is that an apparatus 19 for detecting a rolling reaction force acting in the axial direction of the horizontal roll.
a, 19b, whereby the apparent play that fluctuates during rolling, for example, (δ _VD + δ in the equation (1))
_HTU + δ _F1 ) can be accurately grasped, and by reflecting these in subsequent rolling schedules, it is possible to efficiently and stably remove unevenness in flange thickness.

Next, the second feature of the present invention is to improve the prediction accuracy of the plastic characteristics of the material to be rolled, especially at four flanges, by measuring the rolling reaction force acting in the axial direction of the horizontal roll. It is described that it is possible to efficiently perform. In the universal rolling, the rolling reaction force of each part is mutually affected by the rolling reduction or the rolling distortion of the web part and four flanges, and is further influenced by the shape of the rolling material and the dimensions of each part. The rolling load of each part can be expressed, for example, as follows.

P _H = P _H0 * Q _H + 0.5 * (P _F1 + P _F2 + P _F3 + P _F4 ) tan θ P _F1 = P _F10 * Q _F1 P _F2 = P _F20 * Q _F2 P _F3 = P _F30 * Q _F3 P _F4 = P _F40 * Q _F4 ... (2) P _H0 ; Rolling load of web portion when there is no interaction with flange portion P _Fk0 ; It is assumed that there is no interaction between web portion and other flange portions flange rolling load k of the case; 1-4, flange position Q _H: coefficient taking into account the effects of interaction between the flange portion Q _Fk; factor taking into account the effects of interaction between the web portion and the other flange portion k ; 1-4, flange position

For example, when there is no interaction, the rolling load can be expressed as follows using the plate rolling load formula.

[0023] _{P H0 = k fmw * L H} * l dw * Q PW P Fk0 = k fmFk * B lk * l dFk * Q PFk l dw = {RR H * (t w1 -t w2)} 1/2 l _{dFk = {2RR V * (t} F1k -t F2k)} 1/2 Q PW = (π + l dw / t wm) / 4 Q PFk = (π + l dFk / t Fkm) / 4 t wm = (t w1 + 2 * t _{w2) / 3 t Fkm = (} t F1k + 2 * t F2k) / 3 ... (3) k fmw; mean deformation resistance of the flange portion k;; average deformation resistance k _FmFk web 1-4, flange position L _H; horizontal roll width B _lk; flange width k; 1-4, flange position l _dw; contact arc length of the flange portion k;; contact arc length l _dFk web portion 1-4: flange 4 places RR _H; horizontal roll radius RR _V; vertical roll radius t _wm; average web thickness t _FKM; average flange thickness k; 1 to 4, flange position Q _PW, Q _PFk; rolling force function k; 1 4, flange position

As shown in FIG. 2, for example, as shown in FIG. 2, when the correction of the reduction in the thickness of one flange is made by correcting the position of the horizontal roll in the axial direction, the flange is rolled. Try to stretch in the direction
The other portions apply a compressive force in the rolling direction to restrain this elongation, and the rolling load on the flange increases, while the other flanges receive a tensile force on the contrary, and the rolling load decreases.

As shown in FIG. 2, for example, in a case where the rolling distortion is large only in the upper flange portion 15a on the drive side and the distortions in the other three portions are equal, the other three flanges in the upper portion on the drive side are considered.
The effects on the two places are not the same, the influence on the continuous lower part 15b on the drive side is the largest, and the influence on the two flanges 15c and 15d on the free side is almost equal. In consideration of these, the influence term due to the interaction between the web and the flange can be expressed as follows, for example.

[0026] _{Q H = C 2 * (λ} W -λ FA) + C 3 Q F1 = C 4 * (λ W -a * λ F1 -b * λ F2 -c * λ F3 -c * λ F4) + C 5 Q _F2 = C ₄ * (λ _W -a * λ _F2 -b * λ _F1 -c * λ _F3 -c * λ _F4 ) + C ₅ Q _F3 = C ₄ * (λ _W -a * λ _F3 -b * λ _{F4 -c * λ F1 -c * λ} F2) + C 5 Q F4 = C 4 * (λ W -a * λ F4 -b * λ F3 -c * λ F1 -c * λ F2) + C 5 ... (4) λ _W; web of pressure distortion _{= ln (t w2 / t w1} ) λ Fk; flange of the pressure distortion _{= ln (t F2k / t F1k} ) k; 1~4: flange portion 4 places λ _FA; average pressure distortion of the flange = 0.25 * (ln (t _F21
/ _TF11 ) + ln ( _tF22 / _tF12 ) + ln ( _tF23 / t
_{F13) + ln (t F24 /} t F14)) C 2 ~C 5, a, b, c; shape of the rolled material, the coefficient determined by dimensions, etc.

The advantages of the present invention will be described based on the characteristics of the universal rolling mill described above. Roll the flange thickness accurately, especially by moving the horizontal roll in the axial direction.
In order to remove the uneven wall thickness of the flange at two locations, as can be seen from the equation (1), the rolling reaction force (P _VD , P _VF ) acting on the horizontal and vertical rolls and the rolling reaction force acting on the axial direction of the horizontal roll ( It is important to accurately predict P _F1 −P _F3 , P _F2 −P _F4 ). In a conventional universal rolling mill,
Based on the rolling performance of the horizontal and vertical rolls, it is possible to improve these accuracy, but since the rolling reaction force acting in the axial direction of the horizontal rolls cannot be detected, the prediction accuracy of the rolling load compared with the present invention is improved. It is difficult to make improvements efficiently.

The reason is as follows: (2)-
This is specifically shown below using equation (4). In order to improve the rolling load prediction accuracy, it is necessary to improve the accuracy of the interaction term between the web and each flange based on the rolling performance. It is necessary to calculate the rolling load in the case where there is no interaction of equation (3) from the rolling performance such as distortion of each part, and to improve the accuracy by using these and the rolling load performance of the horizontal and vertical rolls (4) The relationship between the coefficients in the equation can be expressed as follows.

P _VD = P _F1 + P _F2 = P _F10 * Q _F1 + P _F20 * Q _F2 = P _F10 * ｛C ₄ * (λ _W -a * λ _F1 -b * λ _F2 -c * λ _F3 -c * λ _F4 ) + C ₅ ＋ + P _F20 * ｛C ₄ * (λ _W -a * λ _F2 -b * λ _F1 -c * λ _F3 -c * λ _F4 ) + C ₅ ｝ = (P _F10 + P _F20 ) * λ _W * C ₄ −C ₄ * (P _F10 * λ _F1 + P _F20 * λ _F2 ) * a −C ₄ * (P _F10 * λ _F2 + P _F20 * λ _F1 ) * b −C4 * ｛P _F10 * (λ _{F3 + λ F4) + P F20} * (λ F3 + λ F4)} * c + (P F10 + P F20) * C 5 ... (5) P VF = P F3 + P F4 = (P F30 + P F40) * λ W * C 4 −C ₄ * (P _F30 * λ _F3 + P _F40 * λ _F4 ) * a −C ₄ * (P _F30 * λ _F4 + P _F40 * λ _F3 ) * b −C ₄ * ｛P _F30 * (λ _F1 + λ _F2 ) + P _F40 * (λ _F1 + λ _F2 )｝ * c + (P _F30 + P _F40 ) * C ₅ (6)

In the prior art, only a relational expression for improving the above two accuracy can be obtained for each coefficient by one rolling pass. According to the present invention, the rolling reaction force acting in the axial direction of the horizontal roll in one rolling pass (P in the equation (1))
_{Since F1−} P _F3 and P _F2 −P _F4 ) are known, the following two further relational expressions can be obtained for each coefficient of the expression (4).

P _F1 −P _F3 = (P _F10 −P _F30 ) * λ _W C ₄ −C ₄ * (P _F10 * λ _F1 −P _F30 * λ _F3 ) * a−C ₄ * (P _F10 * λ _F2 −P _F30 * λ _F4 ) * b −C ₄ * ｛P _F10 * (λ _F3 + λ _F4 ) −P _F30 * (λ _F1 + λ _F2 )｝ * c + (P _F10 −P _F30 ) * C ₅ … (7 ) P _F2 −P _F4 = (P _F20 −P _F40 ) * λ _W * C ₄ −C ₄ * (P _F20 * λ _F2 −P _F40 * λ _F4 ) * a −C ₄ * (P _F20 * λ _F1 − P _F40 * λ _F3 ) * b −C ₄ * ｛P _F20 * (λ _F3 + λ _F4 ) −P _F40 * (λ _F1 + λ _F2 )｝ * c + (P _F20 −P _F40 ) * C ₅ … (8)

Actually, the coefficients C ₄ , C ₅ , a, b, and c can be obtained with high accuracy by a statistical method, for example, the least-squares method, based on more rolling results. That is, the present invention makes it possible to improve the prediction accuracy of the rolling load based on the rolling performance twice as fast as that of the conventional technology, and to very efficiently perform the plasticity property during rolling, particularly the flange portion. There is a great advantage that the prediction accuracy of the plastic property can be improved.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 3 is a configuration diagram showing Embodiment 1 of the present invention. In FIG.
0 is an edger rolling mill, 15 is a material to be rolled, 16 is a hot dimension gauge, 17 is a first arithmetic unit, and 18 is a second arithmetic unit. That is, in a rolling mill group in which a universal rolling mill 9 and an edger rolling mill 10, which are widely used in the rolling process of an H-section steel, are arranged in pairs, the rolled material 15 is rolled by multi-pass reversal rolling. This is the case where the invention is applied.

The rolling method shown in this example will be described. First, the dimensions of each part of the material to be rolled 15 having undergone the shaping and rolling are measured by a hot dimension meter 16, and the measurement results are obtained by the first arithmetic unit 1
7 together with preset rolling mill characteristics and rolled material plasticity characteristics, for example, measured in advance, and sent to a second arithmetic unit 18 for correcting the pass schedule and setting the rolling position. Here, when there is a deviation between the target dimensions of each part and the measured dimensions, the material to be rolled 15 is rolled using the rolling mill characteristics and the plastic characteristics of the material to be rolled set in the first arithmetic unit 17. The subsequent pass schedule is corrected so as to have the dimensions required at the time of completion, and based on this, the second arithmetic unit 18 determines the rolling position of each roll, that is, in the universal rolling mill 9 of the present invention, the rolling position of the upper and lower horizontal rolls. , The axial position of the upper and lower horizontal rolls, the rolling position of the vertical roll on the drive side and the free side, and the rolling position of the upper and lower rolls in the edger mill 10 are calculated, and each rolling position signal is transmitted to the position setting device of each roll. , Set each roll position. The material to be rolled 15 passes through the universal rolling mill 9 and the edger rolling mill 10 set in this way, and the rolling of the first pass is completed. The rolling of the second pass is also performed in the order of the edger rolling mill 10 and the universal rolling mill 9. However, during the first and second passes, the rolling loads of the upper and lower horizontal rolls, the rolling loads of the drive and free vertical rolls, and the axial rolling reaction force of the upper and lower horizontal rolls are measured. Sent and stored.

Next, the dimensions of each part after the second pass rolling are measured by the hot dimension meter 16, and based on the result, each rolling load and the rolling reaction force at the time of the second pass rolling, the first arithmetic unit 17 described above. Using the relational expressions shown in Expressions (1) to (8), the latest rolling mill characteristics and the plasticity of the material to be rolled are calculated.
These results are sent to the second arithmetic unit 18. In the same manner as before the first pass rolling, if there is a deviation between the target dimensions and the measured dimensions, the latest rolling mill characteristics calculated by the first arithmetic unit 17 and the plastic characteristics of the material to be rolled 15 are obtained. Is used to modify the subsequent pass schedule so that the material to be rolled 15 has the dimensions required at the end of rolling, and based on this, the second arithmetic unit 18 causes the rolling position of each roll to be reduced, that is, the universal rolling mill 9 Calculate the rolling position of the upper and lower horizontal rolls, the axial position of the upper and lower horizontal rolls, the rolling position of the drive side and the free side vertical roll, and further the rolling position of the upper and lower rolls in the edger rolling mill 10,
Each roll position signal is transmitted to each roll position setting device, and each roll position is set. By performing this step up to the final pass, it becomes possible to roll an H-section steel with extremely high dimensional accuracy, particularly without uneven thickness at four flanges.

Embodiment 2 FIG. 4 is a configuration diagram showing Embodiment 2 of the present invention. As shown in FIG. 4, when the present invention is applied to the reversal rolling of a material 15 to be rolled in a rolling mill row in which a universal rolling mill 9 and an edger rolling mill 10 are arranged in tandem, two universal rolling mills of the present invention are used. Machine 9
By arranging the two hot dimension meters 16 at positions close to these, the same operation and effect can be obtained as in the case where the above-described present invention is arranged in a pair of a universal rolling mill and an edger rolling mill. . However, when the present invention is applied to a rolling mill row in which the rolling mills are arranged in tandem,
Even if the present invention is not applied to all universal rolling mills, for example, as shown in FIG.

Embodiment 3 FIG. 6 is a configuration diagram showing the third embodiment of the present invention. When the present invention is applied to the step of rolling the material to be rolled 15 in one pass with a rolling mill row including a plurality of universal rolling mills 9 and an edger rolling mill 10 as shown in FIG. The results are collected only once in each universal rolling mill 9, but the effects of the present invention can be exhibited based on the results of rolling a plurality of materials to be rolled continuously.

[0038]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In this embodiment, the effect of applying the present invention to reversal rolling of a material to be rolled in a rolling mill row in which a universal rolling mill and an edger rolling mill shown in FIG. Was investigated by comparing with the case where the present invention was not applied. Rolled material dimensions were for an H-section steel with a web height of 700 mm and a flange width of 300 mm. Here, the case where the present invention is not applied is a case where the detection result of the axial rolling reaction force of the horizontal roll is not reflected in the improvement of the precision of the rolling mill characteristics and the plastic characteristics of the material to be rolled. In the present embodiment, the dimensions of each part were measured every two passes, and when the dimensional difference from the target dimension was obtained, the average value of the measured values by the dimension meter near the longitudinal center of the material to be rolled was used. Also,
At the start of rolling, the rolling mill characteristics and the plastic characteristics of the material to be rolled were obtained from off-line measurements and rolling experiments.

FIG. 7 shows a comparison of flange thickness accuracy of the first to third flanges immediately after the roll change. Flange uneven thickness Δt
_From the maximum thickness t ₂ max of ₂ and 4 flanges to the minimum thickness t
_The value obtained by subtracting ₂ min is Δt ₂ = t ₂ max −t ₂ min.
In the present invention, the flange thickness deviation Δt ₂ is significantly reduced from the first rolling compared to the conventional method, and the accuracy of the second and third rollings is reduced to about half that of the conventional method. Was clearly recognized. Table 1 shows the results including all the results of the third and subsequent measurements. According to the present invention, it was confirmed that the standard deviation σ of the flange thickness was remarkably improved, and that the accuracy X with respect to the target flange thickness was better than the conventional method.

[0040]

[Table 1]

[0041]

As described above, according to the present invention, it is possible to roll an H-section steel with excellent uniformity of the flange thickness at four places and the absolute value of the flange thickness with high dimensional accuracy. This has the effect that the yield can be improved and the rolling efficiency can be improved by preventing the above.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a rolling device of the present invention.

FIG. 2 is a diagram showing the mutual influence of four flange portions.

FIG. 3 is a configuration diagram of a rolling device according to Embodiment 1 of the present invention.

FIG. 4 is a configuration diagram of a rolling device according to a second embodiment of the present invention.

FIG. 5 is a configuration diagram showing another example of the rolling device of the second embodiment.

FIG. 6 is a configuration diagram of a rolling device according to a third embodiment of the present invention.

FIG. 7 is a graph showing the effect of the present invention in comparison with the case of the conventional method.

FIG. 8 is a schematic view of a conventional hot rolling process for an H-section steel.

FIG. 9 is a view showing a groove shape of a breakdown rolling mill.

FIG. 10 is a cross-sectional view of the crude slab after the breakdown rolling.

FIG. 11 is an explanatory diagram of a rolling load and a reaction force acting on each roll of the universal rolling mill.

[Explanation of symbols]

Reference Signs List 9 universal rolling mill 10 edger rolling mill 13a, 13b horizontal roll 14a, 14b vertical roll 15 material to be rolled 16 hot dimension gauge 17 first arithmetic unit 18 second arithmetic unit 19a, 19b rolling counter in the axial direction of horizontal roll Force detecting device 20a, 20b Horizontal roll rolling load detecting device 21a, 21b Vertical roll rolling load detecting device 22a, 22b Horizontal roll rolling position setting device 23a, 23b Vertical roll rolling position setting device 24a, 24b Horizontal roll axis Direction position setting device

──────────────────────────────────────────────────の Continued on front page (51) Int.Cl. ⁷ Identification code FI B21B 37/18 BBG B21B 37/12 BBG (72) Inventor Makoto Watanabe 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. (72) Inventor Kiyoo Omori 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. (72) Inventor Hisashi Morisaka 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. ( 56) References JP-A 8-150404 (JP, A) JP-A 9-1218 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B21B 37/00-37/78 B21B 1/00-1/46 B21B 13/06 B21B 13/10

Claims (4)

(57) [Claims] In a universal rolling of a material to be rolled, at least a web thickness and a flange thickness and a flange width of four places of the material to be rolled are measured, and a rolling load is applied to upper and lower horizontal rolls and left and right vertical rolls of a universal rolling mill. And the rolling reaction force acting in the axial direction of the horizontal roll is detected, and the measurement result of the material to be rolled, the rolling load of the horizontal roll and the vertical roll, and the rolling reaction force of the horizontal roll in the axial direction are detected. From the force, the characteristics of the universal rolling mill and the plastic characteristics of the material to be rolled are calculated, and the pass schedule of the material to be rolled is corrected based on the calculation result, and the rolling positions of the horizontal roll and the vertical roll are reduced. A method for rolling an H-section steel, comprising setting an axial position of a horizontal roll. 2. In the case where the material to be rolled is rolled by a rolling mill row including at least one universal rolling mill and at least one edger rolling mill, the rolling position of upper and lower horizontal rolls of the edger rolling mill is further determined. 2. The method for rolling an H-section steel according to claim 1, wherein the value is also corrected. 3. A rolling position setting device and a rolling load detecting device installed on each of the upper and lower horizontal rolls and the left and right vertical rolls, and an axial position setting device for setting an axial position of the horizontal roll and acting on the axial direction. A universal rolling mill having a rolling reaction force detecting device that detects a rolling reaction force to be rolled, and is installed at a position close to the universal rolling mill, and measures at least a web thickness and four flange thicknesses and flange widths of a material to be rolled. From the dimension meter, the measurement result by the dimension meter, the rolling load of the horizontal roll and the vertical roll, and the rolling reaction force in the axial direction of the horizontal roll, the characteristics of the universal rolling mill and the plasticity of the material to be rolled. A first computing device for computing the characteristics, a pass schedule of the material to be rolled is corrected based on the computation result, and the horizontal roll and the vertical A rolling device for H-section steel, comprising: a second calculating device that calculates and sets a roll reduction position and an axial position of the horizontal roll. 4. A rolling mill train comprising at least one universal rolling mill and at least one edger rolling mill, wherein the second arithmetic unit further reduces the rolling position of upper and lower horizontal rolls of the edger rolling mill. The rolling device for an H-section steel according to claim 3, wherein the setting is also made by calculating.