JPH09103814A - Rolling process of wide flange shape steel and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling process of wide flange shapes steel which satisfies simultaneously uniformity of thicknesses and leg lengths at flange at four parts, uniformity of left and right flange widths and also realizes absolute value of these dimensions at high precision and further enables even raising yield and rolling efficiency. SOLUTION: Web thicknesses, flange thicknesses at and flange leg lengths at four parts are measured respectively and deviation from each target dimension is operated on the basis of measure results. Each correction quantity of the adjusting quantity of biting attitude or position of rolled stock to obtain wide flange shape steel having each desired dimension by rolling passes thereafter, the roll clearance composed of upper and lower horizontal rollers and vertical rollers and the roll clearance of left and right rollers of edger mill is operated, without any disturbance of shape of rolled stock, based on the biting attitude or position of the rolled stock, the draft of the flange thickness at four parts, the draft of the web thickness, the draft of left and right flange width, deformation characteristics of rolled stock and mill characteristics. On this basis of the operation result, the position of each roller is altered and rolling is carried out at one pass or more passes thereafter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an H-section steel rolling method and apparatus, and more particularly to improvement of dimensional accuracy of H-section steel.

[0002]

2. Description of the Related Art A conventional hot rolling process for H-section steel is schematically shown in FIG. Raw materials such as slabs, blooms or beam blanks heated to a predetermined temperature in the heating furnace 1 are rolled into crude steel pieces by the breakdown rolling mill 2, and then at least one or more universal rolling mills 3 and edger rolling are performed. The rough universal rolling mill group consisting of the rolling mill 4 is rolled to a predetermined size, and the finishing universal rolling mill 5 is rolled to a product shape dimension.

H produced by such a rolling process
The section steel 10 has a web thickness t1 as shown in FIG.
Four flange thicknesses t21, t22, t23, t2
4, left and right flange width B1, B2 and web center deviation S
It is important to roll these dimensions with good accuracy, but it is difficult to roll stably for the following reasons. When manufacturing the existing H-section steel, the yield was reduced and the rolling efficiency was hindered due to the dimensional deviation.

In the breakdown rolling machine 2, a crude steel strip is rolled by a plurality of hole dies 12 as shown in FIG.
Due to the setting position of the centering guide of the material to be rolled, the rolling biting posture or the shape of the hole type and the improper or looseness of the pass schedule, it is difficult to always obtain the desired right and left and right symmetrical rough steel slab. The uneven billet is
This is a factor that reduces the dimensional accuracy of the final product after the subsequent universal rolling.

Further, in the group of coarse universal rolling mills, the universal rolling mill having a pair of horizontal rolls and a pair of vertical rolls allows the web to have a gap between the pair of horizontal rolls and the four flanges to have horizontal rolls and vertical rolls. The gap is pressed down in the thickness direction, and the left and right flange widths are pressed down by an edger rolling machine, and these rollings are repeated until a predetermined dimension is reached. In rolling with the universal rolling mill group, various rolling factors affect the deformation of the web and the flanges at the four places, and these deformations influence each other, so that the thickness and leg length of the flanges at the four places are made uniform. That is, it is difficult to make the flange thickness deviation, the deviation of the center of the web, and the left and right flange width deviations zero.

First, the first reason why it is difficult to make the flange thickness uniform is that the cross-sectional shape of the coarse mesh piece 14 after the break town rolling is not symmetrical vertically and horizontally as shown in FIG. , The gap between the horizontal rolls is proper,
Even if all four gaps between the horizontal roll and the vertical roll are properly set equally and rolled, the thickness of each part corresponding to the flange of the crude steel strip 14 as a rolling material is different,
The rolling reaction force at each of the four flanges is different,
As shown in Fig. 4, not only the vertical roll 20 elastically supported but also the horizontal roll 22 is displaced in the roll axial direction due to the difference in rolling reaction force, so that the thickness of each flange portion after universal rolling is uniform. That is not the case.

The second reason is that even if the cross-sectional shape of the crude steel slab that has finished the breakdown rolling is good in vertical and horizontal symmetry, the horizontal rolling pair and the vertical rolling pair are preliminarily set before rolling in universal rolling. It is extremely difficult to accurately set and confirm the desired gap at present because there is no play in the rolling mill and there is no effective roll gap detector. The rolled material becomes a rolled material having a non-uniform thickness after the next pass after the next pass, which causes a decrease in dimensional accuracy in the final product as described above.

Next, the reason why it is difficult to effectively make the leg length of the flange uniform will be described. The first reason is that the leg lengths at the four places of the flange easily change if the posture or position when the material to be rolled bites into the universal rolling mill is improper, but the biting posture in all rolling passes. Or, it is difficult to optimize the position because it is difficult. The second reason is that the leg length of each flange causes a new difference due to the difference in the width expansion of each flange due to the difference in the rolling reduction in the thickness direction of each flange, and in some cases increases the difference in the flange leg length. , Which also causes an increase in the deviation of the left and right flange widths. The third reason is that it is extremely difficult to make the thickness and leg length of the four flanges at the same time the desired dimensions and uniform.

Regarding the dimensional control in H-section steel rolling,
Various studies have been made, and as a technique for making the thickness of four flanges uniform, there is a technique disclosed in JP-A-6-15327. According to this technology, the flange 4
Although it is effective in reducing the nonuniformity of the thickness at the location, there is a drawback that doing so causes a new dimension defect. In other words, when a crude steel piece after breakdown rolling having uneven thickness at four flanges is used as a raw material and this technique is applied, in order to eliminate this unevenness, there is a difference in the rolling reduction ratio at the four flange portions in the thickness direction. As a result, as shown in FIG. 7, unevenness of the leg length of the flange, that is, deterioration of the web deviation and increase of the difference between the left and right flange widths are caused. Will be invited.

Further, as a technique for suppressing the deviation of the center of the web, JP-A-6-15323 and JP-A-5-17 are available.
7226 publication etc. are mentioned. JP-A-6-15323
What is disclosed in Japanese Patent Publication is a technique for reducing the deviation of the center caused by the difference in the rolling reduction of the four flanges described above, which reduces the difference in the flange leg length, that is, the deviation of the web center. It is not possible to eliminate the uneven thickness and the deviation of the left and right flange widths at four locations at the same time.
Further, what is disclosed in Japanese Unexamined Patent Publication No. 5-177226 is a technique for reducing the deviation of the center by changing the biting position or posture of the material to be rolled, which is described above. There is no preventive effect against changes in each leg length that newly occurs due to the difference in the rolling reduction in the thickness direction, and it is the pass line in the rolling with face angle on the roll like the rough universal rolling, that is, the center of the horizontal roll gap. When the center of the vertical roll width direction is changed, there is a problem that a difference in vertical thickness of the flange occurs.

[0011]

As described above, the conventional technique is effective in improving the individual dimensional accuracy such as improving the uniformity of the wall thickness at the four flanges or suppressing the deviation of the web center. However, there is a problem that it hinders other dimensional accuracy or has no improvement effect. In other words, in the conventional universal rolling method, it is very difficult to simultaneously satisfy the required uniformity of the thickness and leg length of the four flanges and the uniformity of the left and right flange widths. If it is attempted to fit within the range, there is a possibility of inducing dimensional deviation at other locations. In the actual rolling, in the H-shaped steel of a certain size immediately after the start of rolling, the dimensional accuracy of a certain part is inferior, and in extreme cases, there is a deviation in the tolerance, which leads to a decrease in yield. However, there is a problem in that the dimensional deterioration of other parts is caused when trying to correct the above, which hinders the improvement of the yield and the rolling efficiency. Further, in recent years, when the dimensional tolerance is strict and the lot of one size is small like the outer constant H-section steel, the above problem has been extremely difficult to find.

The present invention simultaneously satisfies the required uniformity of the thickness and leg length of the four flanges and the uniformity of the left and right flange widths, which have been difficult in the conventional H-shaped steel rolling by the welding. It is an object of the present invention to provide a rolling method of H-section steel and a device therefor, which can realize the absolute value of H with high precision and further improve the yield and rolling efficiency.

[0013]

According to the present invention, in the process of rolling an H-shaped steel through a group of rough universal rolling mills and a finishing universal rolling mill, at least four flanges of the material to be rolled and four leg lengths of the flange are provided. , The web thickness is measured, and if each dimension is different from the target dimension, the biting posture or position of the rolled material, the vertical horizontal roll in the subsequent one or more passes of rolling from the measurement results. By appropriately setting the roll gap consisting of a pair and a pair of left and right vertical rolls and the left and right roll gaps of the edger, H-section steel with the desired web thickness, four flange thicknesses, and left and right flange width can be rolled. It is what That is, in the present invention, using a crude steel piece obtained by breakdown rolling as a raw material, at least one biting adjusting device or a biting adjusting device capable of adjusting the biting attitude or position of the rolled material is arranged on the rolling entry side, With a universal rolling mill in which horizontal rolls are movably supported in the axial direction and a rough universal rolling mill group consisting of edger rolling mills that can individually adjust the reduction amount of the left and right flange widths, and a rolling mill row consisting of finishing rolling mills. When rolling the H-section steel, at least the flange thickness 4 at a position close to the rough universal mill.
At least one hot dimension gauge for measuring web thickness, at four locations, flange leg length, and web thickness, and calculate the deviation from the target value of each dimension from these measurement results to determine the biting posture or position of the rolled material, flange From the rolling ratio at four locations, the rolling ratio of the web thickness, the rolling ratio of the left and right flange widths, the deformation characteristics of the material to be rolled, and the characteristics of the rolling mill, each desired part in the subsequent rolling pass without disturbing the shape of the material to be rolled The adjustment amount of the biting posture or position of the rolled material to obtain the H-shaped steel having dimensions, the roll gap composed of the upper and lower horizontal rolls and the vertical rolls, and the correction amount of the left and right roll gaps of the edger rolling machine are respectively set. Calculate and change the position of each roll based on this calculation result,
After that, rolling is performed in one or more passes.

First, the relationship between each of the mills and devices constituting the present invention and the deformation characteristics of the material to be rolled will be described. The biting adjusting device 32, which is arranged on the inlet side of the universal rolling and adjusts the biting posture or position of the rolled material, is as shown in FIG. 8 with respect to the vertical horizontal roll gap and the vertical roll gap in the universal rolling mill 34. It is possible to move the rolled material 14 up and down independently of the right and left sides to engage the rolled material 14, as shown in FIG.
In the state shown in (a), that is, in the state in which the center of the gap between the upper and lower horizontal rolls 22 and the web center of the material to be rolled 30 are aligned and the material to be rolled 30 is engaged in parallel to the rolling pass line, universal rolling is performed. If there is no difference in the rolling reduction of the four flanges, there will be no new deviation in the four flange leg lengths. From this state, the biting posture or position of the rolled material is shown in FIG.
When the change is made as shown in (b), the relationship between the change amounts ΔGD and ΔGF of the bite adjusting device 32 and the change amounts of the leg lengths at the four flanges can be expressed as follows. ΔB21 = C1 * ΔGD ΔB22 = −C1 * ΔGD ΔB23 = C1 * ΔGF ΔB24 = −C1 * ΔGF (1) ΔB21; Amount of change in flange leg length on drive upper side ΔB22; Amount of change in flange leg length on drive lower side ΔB23 Change amount of flange leg length on the lower free side ΔB24; change amount of flange leg length on the lower free side C1; coefficient determined by the shape of the rolled material and the degree of restraint of the bite adjusting device with respect to the rolled material

Next, in the universal rolling mill, as shown in FIG.
When the web 14a is rolled in the gap between the upper and lower horizontal rolls 22 and the flange 14b is rolled in the four gaps formed by the upper and lower horizontal rolls 22 and the left and right vertical rolls 20, as shown in FIG. Each roll is elastically displaced by the rolling reaction force. Here, in expressing the axial displacement of the horizontal roll 22, for convenience sake, the lower horizontal roll position is used as a reference, and the roll gap formed by a pair of horizontal rolls 22 with respect to the center of the vertical roll 20 in the cylinder length direction. When the center offset amount is represented by PL, the relationship between the roll gap and the rolling reaction force is represented by the backlash and the mill constant, for example, as follows.

[0016] tw2 = SH + PH / KH + δH tF21 = RVD + (PF1 + PF2) / KVD + RH + (PF1-PF3) / KHT + δVD-PLtanθ tF22 = RVD + (PF1 + PF2) / KVD + (PF2-PF4) / KHT + δVD + P1tanθ tF23 = RVF + (PF3 + PF4) / KVF-RH- (PF1-PF3) / KHT + δVF-PLtanθ tF24 = RVF + (PF3 + PF4) / KVD- (PF2-PF4) / KHT + δVF + PLtanθ (2) tw2; Rolling web downward pressure δH SH: Horizontal roll gap under no load KH: Spring constant of horizontal roll support system PH: Rolling reaction force acting on horizontal rolls PF1: Rolling reaction force i of flange i: 1 to 4, flange position δVj; Vertical roll play RVj; Vertical Roll position j; D, F, drive side or free side vertical roll KVj; Spring constant of vertical roll support system RH; Upper horizontal roll axis movement amount KHT; Horizontal roll axis direction Roll surface angle; spring constant θ of lifting system

The above equation is generally described as the following relational equation. tw2 = F1 (PH, δH, SH0, KH, ...) tF21 = F2 (PF1, PF2, PF3, PF4, δVD, KVD, RVD, RH, KHT, PL ...) tF22 = F3 (PF1, PF2, PF3, PF4) , ΔVD, KVD, RVD, PL, ...) tF23 = F4 (PF1, PF2, PF3, PF4, δVF, KVF, RVF, RH, KHT, PL, ...) tF24 = F5 (PF1, PF2, PF3, PF4, δVF) , KVF, RVF, PL…) (3)

The rolling reaction force of each part mutually influences the reduction ratio or the reduction strain of the web part and the four flanges,
Further, since it is influenced by the shape of the rolled material and the size of each part, it is expressed as follows, for example. PH = PH0 * QH + 0.5 * (PF1 + PF2 + PF3 + PF4) tan θ PF1 = PF10 * QF1 PF2 = PF20 * QF2 PF3 = PF30 * QF3 PF4 = PF40 * QF4… (4) If there is no interaction with the flange part Rolling load of web part PFk0 in case of; Rolling load of flange part when there is no interaction with web part k; 1-4, flange position QH; Coefficient Qfk considering effect of interaction with flange part; Flange part Coefficients in consideration of the influence of the interaction with and k; 1-4, flange position For example, the rolling load in the case where there is no interaction is expressed as follows using the load formula of plate rolling.

[0019]

(Equation 1)

The influence term due to the interaction between the web and the flange is expressed as follows, for example. QH = C2 * (λw-λFA) + C3 QFk = C4 * (λw-λFA + C4'λFK) + C5k; 1 to 4, flange position (6) λw; web rolling strain = ln (tw2 / tw1) λFk; flange Strain of rolling = 1n (tF2k / tF1k) λFA; Average rolling strain of flange = 0.25 * (1n (tF21 /
tF11) + 1n (tF22 / tF12) + 1n (tF23 / tF13) + 1n (tF
24 / tF14)) C2 to C5; Coefficient determined by the shape and dimensions of the rolled material

The relationship between the rolling reaction force and the rolling strain is generally described as follows. PH = F6 (tw1, tF11 to tF14, B11 to B14, tw2, tF21 to tF24, B21 to B24, PF1 to PF4, ...) PF1 = F7 (tw1, tF11 to tF14, B11 to B14, tw2, tF21 to tF21, tF24, tF21, tF24 B21 to B24, ...) PF2 = F8 (tw1, tF11 to tF14, B11 to B14, tw2, tF21 to tF24, B21 to B24, ...) PF3 = F9 (tw1, tF11 to tF14, B11 to B14, tw2, tF21). tF24, B21 to B24, ...) PF4 = F10 (tw1, tF11 to tF14, B11 to B14, tw2, tF21 to tF24, B21 to B24, ...) (7)

Further, the change in the leg length of the flange in the universal rolling takes into consideration the mutual influence with the web portion similarly to the rolling reaction force, and due to the pressure strain in the thickness direction of each flange portion and the thickness direction rolling strain of the web portion, for example, It is expressed as follows. ln (B2k / B1k) = C6 (λw-λFA) + C7 (λW-λFk) + C8 (8) C6 to C8; Coefficient k determined by shape and size of rolled material; 1 to 4, flange position Generally, it is expressed as follows. B21 = F11 (tw1, tF11 to tF14, B11 to B14, tw2, tF21 to tF24, ...) B22 = F12 (tw1, tF11 to tF14, B11 to B14, tw2, tF21 to tF24, ...) B23 = F13 (tw1, tF11 to tF14, B11 to B14, tw2, tF21 to tF24, ...) B24 = F14 (tw1, tF11 to tF14, B11 to B14, tw2, tF21 to tF24, ...) (9) twi; Web thickness tFij; Flange thickness i; 1: dimensions before universal rolling 2: dimensions after universal rolling Bij; flange width j; 1 to 4: 4 flange portions

Similarly in the edger rolling, the relationship between the roll gap and the rolling reaction force is expressed as follows by the play and the spring constant of the elastic system supporting the roll. B21 + B22 = SD + PD / KED + [delta] D B23 + B24 = SF + PE / KEF + [delta] F (10) SD, SF; Drive side, free side edger roll gaps [delta] D, [delta] F; drive side, free side edger roll rattle KED, KEF; edger roll drive side , Free side support system spring constants PD and PF; Drive side and free side edger roll reaction force

The rolling reaction force is balanced between the upper and lower sides on the drive side and the upper and lower sides on the free side, and is expressed as follows, for example.

[0025]

(Equation 2)

Further, the thickness of the web portion and each flange portion changes due to edging, and is represented as follows, for example. ln (tw2 / tw1) =-γk ln (B1k / B2k) ln (tF2k / tF1k) = (1-γk) ln (B1k / B2k) (12) γk; coefficient determined by the size and shape of the rolled material Edger From the above relationships, the dimension of each part in rolling is generally expressed as follows. tw2 = E1 (tw1, tF11 to tF14, B11 to B14, tF21 to tF24, B21 to B24, ...) tF21 = E2 (tw1, tF11 to tF14, B11 to B14, tW2, tF22 to tF24, B24 to B21 to B24). tF22 = E3 (tw1, tF11 to tF14, B11 to B14, tW2, tF21, tF23 to tF24, B21 to B24, ...) tF23 = E4 (tw1, tF11 to tF14, B11 to B14, tW2, tF21 to t21, tF21 to t21, tW2, tF21 to t21). -B24, ...) tF24 = E5 (tw1, tF11-tF14, B11-B14, tW2, tF21-tF23, B21-B24, ...) B21 + B22 = E6 (tw1, tF11-tF14, B11-B14, SD2, SF, SF2). , TF21 to tF24, B23 to B24) B21 + B22 = E7 (tw1, tF11 to tF14, B11 to B14, SD, SF, tW2, tF21 to tF24, B23 to B24) B23 + B24 = E8 (tb11 to TF11, tF14, tF11, tF14). , SD, SF, tW2, tF21 to tF24, B21 to B22) B23 + B24 = E8 (tw1, t F11 to tF14, B11 to B14, SD, SF, tW2, tF21 to tF24, B21 to B22) (13) twi; web thickness tFij; flange thickness i; 1: edger rolling dimension 2: edger rolling dimension Bij; Flange width j; 1-4: 4 flange parts

The relationship between the deformation characteristics of each mill and the roll gap has been presented above. However, it is complicated or difficult to express the relationship between the dimensions of each part and the roll gap from these non-linear relations. In the case of correcting the roll gap by rolling, it is sufficient to obtain the correction amount. Therefore, by expanding each equation of (2) to (13) by Taylor and considering only the primary term, The dimensional change of each part on the outlet side of the mill and the apparatus can be expressed by a linear relational expression of the dimensional change of the inlet side and the roll gap change. For example, the change amount Δtw2 of the outgoing web thickness in universal rolling is expressed as follows. Expression (2) can be expressed as a change amount. Δtw2 = ΔSH + ΔPH / KH (14) When formula (4) regarding the rolling reaction force of each part is developed,

[0028]

(Equation 3)

By substituting this into (14), the linear relational form is generally expressed as follows. Δtw2 = a1 * Δtw1 + a2 * ΔtF11 + a3 * ΔtF12 + a4 * ΔtF13 + a5 * ΔtF14 + a6 * ΔB11 + a7 * ΔB12 + a8 * ΔB13 + a9 * ΔB14 + ΔΔt, BtΔF14 + a12 * F14 + a12 * F14 + a12 * 14 + A12 * a14 * 14 * 14 , ∆tF21 to ∆tF24, ∆B21 to ∆B24) am; coefficient m = 1 to 14 determined by the size, shape, roll gap setting value, etc. of the press material.

Similarly, the flange thickness and leg length of each outgoing side in universal rolling are expressed as follows. ΔtF21 = f2 (Δtw1, ΔtF11 to ΔtF14, ΔB11 to ΔB14, ΔSH, ΔRH, ΔRVD, ΔRVF, ΔPL, Δtw2, ΔtF22 to ΔtF24, ΔB21 to ΔF14, ΔF14, ΔT14, ΔT14, ΔTF14, ΔTF14, ΔT14, ΔF14, ΔTF14, ΔT21, ΔF14, ΔF14, ΔT21, ΔF21, ΔF14, ΔT21 ΔRH, ΔRVD, ΔRVF, ΔPL, Δtw2, ΔtF21, ΔtF23 to ΔtF24, ΔB21 to ΔB24) ΔtF23 = f4 (Δtw1, ΔtF11 to ΔtF14, ΔB11 to ΔF21, ΔR2, ΔR, ΔR, ΔR) , TF24, ΔB21 to ΔB24) ΔtF24 = f5 (Δtw1, ΔtF11 to ΔtF14, ΔB11 to ΔB14, ΔSH, ΔRH, ΔRVD, ΔRVF, ΔPL, Δtw2, ΔtF21 to ΔtF23, ΔB21 to Δf21 Δt21 = ΔB21 to ΔB21 = ΔB21 to ΔB21 = ΔB21 to ΔB21 = ΔB21 to ΔB21 = ΔB21 to ΔB21 = ΔB21 to ΔB21 = ΔB21 to ΔB21 = ΔB21 to ΔF21 to Δt21. , ΔB11 to ΔB14, ΔSH, ΔRH, ΔRVD, ΔRVF, ΔPL, Δtw2, ΔtF21 to ΔtF24, ΔB23 to ΔB24) ΔB22 = f7 (Δtw1, ΔtF11 to ΔtF14, ΔB11 to ΔB14, ΔSH, ΔR, ΔSH, ΔR, ΔR). D, ∆RVF, ∆PL, ∆tw2, ∆tF21 to ∆tF24, ∆B23 to ∆B24) ∆B23 = f8 (∆tw1, ∆tF11 to ∆tF14, ∆B11 to ∆B14, ∆SH, ∆RH, ∆RVD, ∆RVF, ∆PLB, ∆F21, ∆T2, ∆tw2, ∆T2), ∆T2, ∆T2 and ∆T2. ΔB24 = f9 (Δtw1, ΔtF11 to ΔtF14, ΔB11 to ΔB14, ΔSH, ΔRH, ΔRVD, ΔRVF, ΔPL, Δtw2, ΔtF21 to ΔtF24, ΔB21 to ΔB22) (16)

Further, in the device for adjusting the biting of the rolled material, since the thickness of each part does not change, the change amount of the web thickness, the thickness of each part of the flange and the leg length, that is, the dimensional change amount at 9 places is (1).
From the formula, it is expressed as follows. Δtw2 = 0 ΔtF21 = 0 ΔtF22 = 0 ΔtF23 = 0 ΔtF24 = 0 ΔB21 = C1 * ΔGD ΔB22 = -C1 * ΔGD ΔB23 = C1 * ΔGF ΔB24 = -C1 * ΔGF (17)

Further, also in the edger rolling, the dimensional change amount of each outgoing side portion is expressed by the following equation (13). Δtw2 = g1 (Δtw1, ΔtF11 to ΔtF14, ΔB11 to ΔB14, ΔSD, ΔSF, ΔtF21 to ΔtF24, ΔB21 to ΔB24) ΔtF21 = g2 (Δtw1, ΔtF11 to Δt14, Δt22, ΔF14, ΔF14, ΔF14, ΔF14, ΔF14, ΔF14, ΔF14, ΔT14, Δt14 ΔB21 to ΔB24) ΔtF22 = g3 (Δtw1, ΔtF11 to ΔtF14 to ΔtF14, ΔB11 to ΔB14, ΔSD, ΔSF, Δtw2, ΔtF21, ΔtF23 to ΔtF24, ΔB21 to ΔB14, ΔtB14, Δt14, Δt14, Δt14, ΔtB14, ΔtF14, ΔtF14, ΔtB14, ΔtF14, ΔtF14, ΔtF14, ΔtF14, ΔtF14, ΔtB1 ΔSF, ΔtF21 to ΔtF22, ΔtF24, ΔB21 to ΔB24) ΔtF24 = g5 (Δtw1, ΔtF11 to ΔtF14, ΔB11 to ΔB14, ΔSD, ΔSF, Δtw2, ΔtF21 to Δt14, ΔB21 to Δt14, ΔB21 to Δt14, ΔB21 to Δt21, ΔB21 to Δt + 23, ΔB21 to Δt21, ΔB21 to Δt + 23, ΔB21 to Δt + 23, ΔB21 to Δt + 23, ΔB21 to ΔtF23, ΔB21 to Δt + 23, ΔB21 to Δt + 23, ΔB21 to Δt + 23. ΔB11 to ΔB14, ΔSD, ΔSF, Δtw2, ΔtF21 to ΔtF24, ΔB23 to ΔB24) ΔB21 + ΔB22 = g7 (Δtw1, ΔtF11 to ΔtF14, ΔB11 to ΔB14, ΔSD, ΔS) , Δtw2, ΔtF21 to ΔtF24 to ΔtF24, ΔB23 to ΔB24) ΔB23 + ΔB24 = g8 (Δtw1, ΔtF11 to ΔtF14, ΔB11 to ΔB14, ΔSD, ΔSF, Δtw2, ΔtF21 ΔtF21 to Δt11, ΔB21 to Δt14, ΔB21 to Δt14, ΔB21 to Δt14, ΔB21 to Δt21, ΔB21 to Δt14, ΔB21 to ΔtΔ24, ΔB21 to ΔtF24, ΔB21 to ΔtF24, ΔB21 to ΔtF24, ΔB21 to ΔtF24, ΔB21 to ΔtF24, ΔB21 to ΔtΔ24, ΔB21 to ΔtF24, ΔB21 to ΔtF24, ΔB21 to ΔtF24, ΔB21 to ΔtΔ24. To ΔB14, ΔSD, ΔSF, Δtw2, ΔtF21 to ΔtF24, ΔB21 to ΔB22) (18) Δ: change amount

As shown in the above equations (16) to (18), it is possible to obtain a linear relational form corresponding to the nine outlet side dimensional changes in each mill and device.

Here, at least the web thickness, 4
A method for obtaining an H-section steel having a desired dimension in the subsequent rolling passes according to the present invention will be described when deviations from target values are obtained as a result of measuring the flange thicknesses at four places and the flange leg lengths at four places.

The deviation between the target dimension and the measurement result at the time of measurement with the dimension meter, the dimensional change amount, and the roll gap correction amount are represented by Δ, and the deviation between the measurement result and the dimension of each part is adjusted by adjusting the biting position of the material. An example of eliminating a dimensional deviation by one-pass rolling in a line composed of a device, a universal rolling mill and an edger rolling mill is shown.

FIG. 1 shows an arrangement example of the dimension measuring machine 30, the material bite adjusting device 32, the universal rolling machine 34 and the edger rolling machine 36, and the dimensional change amount of the material to be rolled at each position and the roll gap correction. Indicates the amount. The deviation of the size of each part on the entrance side of the material to be rolled from the target value is known, and the amount of dimensional change of each part after the completion of one-pass rolling is “0” to match the target value, and is known, and the number is Eighteen. What should be obtained, that is unknown, is the roll gap and biting position correction amount for correcting the dimensional deviation on the entrance side, and the dimensional change amount of the rolled material rolled by the corrected roll gap, the number of which is 27.

The relational expressions for obtaining the unknown amount of dimensional change, roll gap, and bite position correction amount are as follows: in universal rolling, the web thickness after rolling, the four flange thicknesses, and the four flange leg lengths left and right. There are nine relational expressions (16) regarding the change amount, and nine relational expressions (18) for each dimensional change even in the edger rolling. In the bite adjustment device 32, there are also nine relational expressions. Equation (17), which is a total of 27 relational equations, is obtained in advance by experiments and calculations as in the equations (2), (4), (5), and (6). That is, the unknown amount to be obtained and the number of relational expressions are equal to 27, and it is possible to uniquely obtain each roll gap and the biting position correction amount that should correct the inlet side dimension deviation of the rolled material in one pass. It is possible.

That is, in order to simultaneously finish the uniformity of the flange thickness and the flange leg length at four places and the absolute values of these dimensions to the target dimensions, the universal rolling mill according to the present invention can move the horizontal rolls in the axial direction. In addition, in the edger rolling mill, the roll gap corresponding to the reduction of the left and right flange width can be set individually, and it is arranged on the universal rolling entry side, and the biting position on the drive side and the free side can be adjusted independently. This means that it is essential to measure at least the web thickness, the flange thickness at four locations, and the flange leg lengths at four locations, which means that it is impossible with the prior art.

Next, according to the present invention, by rolling in two or more passes,
An example of a method of correcting the deviation of the entry side dimension of the material to be rolled from the target value will be shown. Universal rolling mill 34 (U1, U
2) and an arrangement example of the edger rolling mill 36 (E1, E2),
The amount of dimensional change of the material to be rolled at each position, the roll gap, and the biting position correction amount are shown. Similar to the case of correction with one pass, the deviation from the target value of each part size on the entrance side of the material to be rolled is known from the measurement result of the dimension gauge, and the dimensional change amount of each part after rolling is equal to the target value. It is known as "0" for matching, and the number is 18 as in the case of correction by one-pass rolling. What should be obtained, that is unknown, is the roll gap and biting position correction amount for correcting the dimensional deviation on the entrance side, and the dimensional change amount of the rolled material rolled by the corrected roll gap, the number of which is 52.

The relational expressions for obtaining the unknown amount of dimensional change, roll gap and bite position correction amount are the same for the bite adjustment device, universal rolling and edger rolling as in the case of correction in one pass. There are nine relational expressions relating to the changes in the web thickness afterward, the flange thickness at four locations, and the flange leg lengths at four locations, and in the case shown in FIG.
Five relational expressions are used.

Further, if the size is to be corrected by two or more passes, more conditional expressions are required. That is,
Now, the number of unknown quantities is 52 and the relational expression is 45, and it is impossible to uniquely obtain all unknown quantities. This is because, as described above, the dimensional deviation on the entry side can be corrected by one-pass rolling, and therefore, when it is corrected by two-pass rolling or more, a relational expression of the correction method is required. . This is not a disadvantage in terms of dimensional correction, but rather in actual rolling. Sunahachi 2
This is because, when the dimension correction is performed with more than one pass, it becomes possible to consider the relational expression for suppressing the shape defects such as warpage and bending of the rolled material during rolling, which could not be considered in the one-pass rolling, in the dimension correction. .

Shape defects such as warpage and bending at the time of rolling are caused by excessive differences in the reduction ratio of the flange thickness at four places. Therefore, when the dimension is corrected by rolling at two or more passes, there are four places at one pass. Compared with the reduction ratio required to eliminate the flange thickness, it is possible to reduce the difference in the reduction ratio of each part of the flange in each pass, and it is possible to correct the dimension while suppressing defective shapes.

Various relational expressions can be considered when the dimension is corrected by two or more passes. For example, it is known that defective shapes are less likely to occur when the difference in the reduction rate of each flange thickness is the same when the flange thickness is thicker than when the flange thickness is thin. The formula is ΔSH1 / ΔSH2 = α1 ΔRVD1 / ΔRVD2 = α2 ΔSD1 / ΔSD2 = α6 ΔRVF1 / ΔVRF2 = α3 ΔSF1 / ΔSF2 = α7 ΔRH1 / ΔRH2 = α4 αi ≧ 1.0 ΔPL1 / ΔPL2 = α5 ... By creating a relational expression and combining it with the relational expression of the dimensional change amount of each portion, the relational expression becomes 52, and the roll gap correction amount for correcting the entrance side dimensional deviation in two passes can be obtained. In addition, here, an example of dimension correction by two passes is shown, but it is also possible to perform the correction by three or more passes.

Further, in the present invention, as can be easily inferred from the above description, the dimension at the end of rolling is intentionally made nonuniform, that is, the roll gap is modified to arbitrarily change the dimension of each part. I will add that it is possible. Furthermore, when the dimensions of each part are measured over the entire length of the material to be rolled and the roll gap and the biting position of the mill and the device constituting the present invention can be corrected quickly, the effect of the present invention is exerted over the entire length of the material to be rolled. Obtainable.

[0045]

BEST MODE FOR CARRYING OUT THE INVENTION FIG. 11 shows rolling equipment suitable for carrying out the present invention. In the figure, 1 is a heating furnace, 2 is a breakdown rolling mill, 30 is a hot dimension gauge,
32 is a biting adjusting device, 34 and 34 'are rough universal rolling mills, 36 and 36' are edger rolling mills, 38 is a finishing rolling mill, and 40 is a computing device.

The arithmetic unit 40 calculates the deviation from the target value of each dimension and the measurement result of the hot dimension meter 30 and corrects the dimension deviation from the previously obtained relational expression. The correction amount of the gap and the biting position and the dimensional change amount of the rolled material are calculated. Further, all roll positions are adjusted based on the result of adding the roll gap correction amount to the set roll gap value. By performing such a process once or more, the uniformity of the flange thickness at four locations, the uniformity of the flange leg lengths at four locations, that is, the deviation of the web center and the deviation of the left and right flange widths do not occur, and the web thickness, flange thickness, The absolute value of the flange width can be finished to the desired size.
For this reason, even in a rolled material of a certain size immediately after the start of rolling, it does not deviate from the desired dimension, the yield reduction due to the dimension deviation can be eliminated, and the rolling efficiency is improved.

[0047]

EXAMPLE A web height of 7 was obtained using the equipment shown in FIG.
H-section steel having a length of 00 mm and a flange width of 300 mm was hot-rolled, and the respective dimensions of the product in the case of applying the present invention and in the case of not applying the present invention, that is, the prior art were investigated. In this embodiment,
When the present invention is applied to the final five-pass rolling of the rough universal rolling and the dimension measurement of each part is performed every two passes and the dimension deviation from the target dimension is obtained, the dimension meter near the central portion in the longitudinal direction of the rolled material is measured. The average value of the measured values according to Further, in the present embodiment, αi in the above-mentioned formula (19) is a coefficient proportional to the thickness of each part, so that the disorder of the shape during rolling does not pose a problem.

Table 1 shows the results of the investigation of the web thickness, the four flange thicknesses, and the four flange leg lengths in comparison with the case where the present invention is not applied (conventional method). As is clear from Table 1, in the present invention, the uniformity of the flange thickness and the uniformity of the flange leg length are remarkably good, and the average value (absolute value) of the web thickness flange thickness and the flange leg length is substantially equal to the desired dimension. It has been confirmed that it is effective in achieving good dimensional accuracy.

[0049]

[Table 1]

[0050]

As described above, according to the present invention, the web thickness of the H-section steel after shaping and rolling, the four flange thicknesses, and the four flange leg lengths are respectively provided at the upstream and adjacent positions close to each other. Measure and calculate the deviation from each target dimension based on this measurement result, biting posture or position of rolled material, rolling reduction at four flange thicknesses, rolling reduction of web thickness, rolling reduction of left and right flange widths, rolled material From the deformation characteristics of the material and the characteristics of the rolling mill, the amount of adjustment of the biting posture or position of the rolled material in order to obtain the H-section steel having the desired dimensions in each subsequent rolling pass without disturbing the shape of the material to be rolled , A roll gap composed of upper and lower horizontal rolls and a vertical roll, and correction amounts of the left and right roll gaps of the edger rolling machine are calculated, and the position of each roll is changed based on the calculation result.
Since rolling is performed with more than one pass, it is possible to roll H-section steel with high dimensional accuracy in flange thickness, flange width, and web thickness. By preventing dimensional deviation, yield and rolling efficiency can be improved. Becomes

[Brief description of the drawings]

FIG. 1 is an arrangement of a material biting position adjusting device, a universal rolling machine and an edger rolling machine in a rolling line according to the present invention, and a dimensional change amount of a material to be rolled, a roll gap correction amount and a biting position at each position thereof. It is explanatory drawing which showed the correction amount.

FIG. 2 is a schematic diagram of a hot rolling process for H-section steel.

FIG. 3 is an explanatory diagram of dimensions (tolerance) of H-section steel.

FIG. 4 is an explanatory diagram of breakdown rolling.

FIG. 5 is an explanatory view showing a cross-sectional shape of a crude steel slab that has finished the breakdown rolling.

FIG. 6 is an explanatory diagram showing displacement of a crude steel piece, a vertical roll, and a horizontal roll.

FIG. 7 is an explanatory diagram illustrating unevenness of the flange leg length that occurs when there is a difference in the rolling reduction in the thickness direction at four points of the flange portion.

FIG. 8 is a side view of a rolling line and a sectional view of a rolling entry side in the present invention.

9A is a rolling direction sectional view and a universal rolling inlet side sectional view of a biting position adjusting device, and FIG. 9B is a sectional view showing a state in which the biting amount is adjusted in the state of FIG. 9A. FIG. 3 is a cross-sectional view in the rolling direction and a cross-sectional view in the universal rolling entry side of the bite position adjusting device in the case of performing.

FIG. 10 is an arrangement of universal rolling mills and edger rolling mills when the deviation from the target value of the inlet side dimension of the material to be rolled is corrected by rolling in two or more passes in the present invention, and the material to be rolled at each position thereof. FIG. 6 is an explanatory view showing the dimensional change amount, roll gap correction amount, and bite position correction amount.

FIG. 11 is a schematic diagram showing an arrangement example of rolling equipment according to an example of an embodiment of the present invention.

Front page continuation (72) Inventor Motohisa Yoshida Marunouchi 1-2-2 Nihon Steel Pipe Co., Ltd. in Chiyoda-ku, Tokyo (72) Inventor Naoki Kataoka 1-2-1 Marunouchi Chiyoda-ku Tokyo Within the corporation

Claims (2)

[Claims] 1. A universal rolling mill in which a biting adjusting device capable of adjusting the biting posture or position of a rolled material is arranged on the rolling-in side, and a horizontal roll is supported so as to be movable in the axial direction; In a rolling method by a group of universal rolling mills for H-section steel rolling, each of which includes an edger rolling mill whose flange width reduction roll gap on the free side can be individually set, a shaping method is provided at a position close to the upstream side of the universal rolling mill. After rolling, measure the web thickness of the H-section steel, the flange thickness at 4 locations, and the flange leg length at 4 locations, and calculate the deviation from each target dimension based on the measurement results to determine the biting posture or position of the rolled material, and the flange. Without reducing the shape of the material to be rolled, from the rolling reduction at four locations, the web thickness rolling reduction, the left and right flange width rolling reduction, the deformation characteristics of the rolled material, and the characteristics of the rolling mill. Amount of adjustment of biting posture or position of rolled material to obtain H-section steel having desired dimensions in each rolling pass, roll gap composed of upper and lower horizontal rolls and vertical rolls, left and right rolls of edger rolling mill The amount of correction of the gap is calculated, the position of each roll is changed based on the calculation result, and rolling is performed in one or more passes thereafter.
Shaped steel rolling method. 2. A universal rolling mill in which a biting adjusting device capable of adjusting the biting posture or position of a rolled material is arranged on the rolling entry side, and a horizontal roll is supported so as to be movable in the axial direction,
And a group of universal rolling mills for H-section steel rolling, each equipped with an edger rolling mill capable of individually setting the flange width reduction roll gaps of the drive side and the free side, and at a position close to the upstream side of the universal rolling mill. The hot dimension gauges arranged and measuring the web thickness, the flange thickness at 4 locations, and the flange leg lengths at 4 locations of the H-shaped steel after shaping and rolling, and the deviation from each target dimension based on the measurement result by the hot dimension gauge Is calculated from the biting posture or position of the rolled material, the reduction ratio of the four flange thicknesses, the reduction ratio of the web thickness, the reduction ratio of the left and right flange widths, the deformation characteristics of the rolled material and the characteristics of the rolling mill. Of the rolled material in order to obtain the H-section steel having desired dimensions in each subsequent rolling pass without disturbing the shape of the roll, the roll formed by the upper and lower horizontal rolls and the vertical rolls. H and a calculation device for calculating the correction amount of the left and right roll gaps of the edger rolling mill, changing the position of each roll based on the calculation result, and rolling in one or more passes thereafter. Shaped steel rolling equipment.