JPH0929302A - Method for rolling wide-flange shape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correct a wide-flange shape in which the offset of the web center is generated in the process of rolling, to surely dissolve the offset of the web center and to correct even the asymmetrical offset of the web center in the universal rolling of the wide-flange shape. SOLUTION: Based on the measured values SR, SL of the offset of the right and left web centers of a material to be rolled which are obtained with a shape measuring device 10 provided in the vicinity of a universal mill BD or an edger mill E, the center position CV of the barrel parts of vertical rolls to the center position CV to the center position CH of the gap between the upper and lower horizontal rolls of the universal mill are respectively individually vertically adjusted with a pair of right and left vertical rolls VR, VL and the web position is vertically moved for correction by changing the contact length of the upper and lower parts of the flanges to the vertical rolls V and the offset of the web center is dissolved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to the rolling of H-section steel used for hot-rolling a material to be rolled such as H-section steel used in construction and civil engineering using a universal rolling mill. It is about the method.

[0002]

2. Description of the Related Art An H-section steel production line is shown in FIG.
As shown in (a), the breakdown mill BD (double rolling mill), the rough universal mill UR, the edger mill E, and the finishing universal mill UF are arranged in this order from the upstream side. After rolling into a rough steel slab provided with a flange and a plurality of passes in the rough universal mill UR and the edger mill E, the rough universal slab is finished.
Normally, the product is finished to a specified product size by one-pass finish rolling in F (see FIG. 4B).

The universal mill comprises a pair of upper and lower horizontal rolls H and a pair of left and right vertical rolls V arranged at the same position. The web 1w of the material 1 to be rolled is a vertical horizontal roll H and the flange 1f is a vertical roll V. And the side surfaces of the upper and lower horizontal rolls H are rolled to a predetermined thickness. However, in a normal-purpose universal mill, a so-called web center deviation occurs in which the web position is vertically displaced from the flange center due to the reason described later. To do.

That is, as shown in FIG. 4 (c), the flange width of the material 1 to be rolled changes every time it passes through the rolling mill, so that the distance h ₁ from the upper surface of the roller table to the center of the inlet web 1w. Does not correspond to the distance to the center h ₂ of the gap of the upper and lower horizontal rolls H, on the other hand, the flange reduction amount is generally larger than the web reduction amount, and the flange comes into contact with the roll ahead of the web. l _f > l
_w ), the web 1w is bitten in the vertical horizontal roll H, and the web 1w is in the vertical direction in a state where the restraint ranges (portions indicated by diagonal lines) of the flanges restrained by the side faces of the vertical roll V and the horizontal rolls H are different from each other. After that, the web center is biased and the web center is biased.

In recent years, when dimensional accuracy is required, it is necessary to reduce the deviation of the center of the web to improve the dimensional accuracy. As means for preventing the deviation of the center of the web, various conventional methods have been used. It has been proposed, and there are the following methods, for example.

Universal rolling mill (Japanese Patent Laid-Open No. 57-9
No. 7807 gazette) A vertical roll of a universal rolling mill can be moved by a wedge member in an inward / outward direction of the rolling mill (rolling direction), and a web biting start point of a horizontal roll and a flange biting start point of a vertical roll are provided. The dimensions are the same and the dimensional accuracy is improved. Hereinafter, it will be referred to as Conventional Method I.

Shaped steel rolling method and apparatus
The upper and lower horizontal rolls of the universal rolling mill can be individually moved up and down by the lift device, and the inner stand having a pair of left and right vertical rolls can be vertically moved by the lift device. The pass line is obtained based on the measured value by the flange width meter provided on the upper and lower horizontal roll gap centers and the vertical roll center of the inner stand are aligned with the pass line, and the center of the material to be rolled is aligned with the pass line. This prevents the web center from being biased. Hereinafter, it is referred to as Conventional Method II.

Rolling method for H-section steel (Japanese Patent Application Laid-Open No. 59-19
Also in this case, the horizontal roll is moved up and down to adjust the pass line of the horizontal roll according to the dimensional variation of the flange width of the material to be rolled, and the vertical roll is moved up and down by using the taper block. By adjusting the pass line of, the deviation of the web center is prevented. Hereinafter, it is referred to as Conventional Method III.

Universal rolling method for a profile having a flange (Japanese Patent Laid-Open No. 4-22501) A pair of right and left vertical rolls of a universal rolling mill is moved in the rolling direction so that the web biting position is more than the flange biting position. By rolling in advance, the center deviation of the web is improved. Hereinafter referred to as Conventional Method IV.

Rolling Method for H-Shaped Steel with Small Center Deviation (Japanese Patent Laid-Open No. 6-15323) When rolling H-shaped steel with a rolling facility composed of a combination of a breakdown mill, a rough universal mill, an edger mill and a finishing universal mill. , Measuring the deviation amount of the center in the proximity area of the rough universal mill, and in order to keep the deviation amount of the center within 0 or an allowable range, the deviation of the position of the upper and lower horizontal rolls of the coarse universal mill in the roll axial direction in the next pass, After calculating the deviation of the roll opening between the left and right vertical rolls and the deviation of the center position of the gap between the upper and lower horizontal rolls with respect to the center position of the vertical roll body, change the roll position of each roll based on this calculation result, and then perform one or more passes. Is rolling in. Hereinafter, it is referred to as the conventional method V.

[0011]

However, in the conventional methods I to IV described above, the deviation of the web center is prevented by adjusting the biting start point or the pass line position. The effect of suppressing the deviation of the web center is small, and the deviation of the web center once generated cannot be corrected.

Further, in the conventional method V, as shown in FIG. 5 (a), the gap center position C _H of the upper and lower horizontal rolls H, when giving a deviation with respect to the barrel center position C _V of the vertical rolls V, Since it is performed by moving the position of the upper and lower horizontal rolls H, it is possible to correct the lateral deviation of the web center shown in FIG. 5B, but the lateral deviation of the web center as shown in FIG. It is difficult to fix.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to correct an H-section steel having a deviation in the center of the web during rolling, and to make the deviation in the center of the web. SUMMARY OF THE INVENTION An object of the present invention is to provide a rolling method for H-section steel capable of reliably eliminating the above-mentioned problems and correcting the lateral deviation of the web center.

[0014]

In order to achieve the above object, in the present invention, by vertically shifting the vertical roll body center position (flange pass line) with respect to the gap center position of the upper and lower horizontal rolls of the universal mill, The contact length to the vertical rolls above and below the flange is changed, which allows the web position to be adjusted up and down, which is used to determine the corresponding vertical roll based on the deviation measurement value of the web center measured in a predetermined pass. Move up and down with a pass,
This vertical roll straightens and rolls the flange.

That is, as shown in FIG. 1, when a rough shaped steel piece provided with a web and a flange is rolled using a rough universal mill BD, an edger mill E and a finishing universal mill UF to produce an H-shaped steel, Based on the web center deviation measurement values S _R and S _L of the left and right flanges of the material to be rolled obtained by the shape measuring device 10 installed near the rough universal mill BD or the edger mill E, the upper and lower horizontal rolls of the universal mill are measured. The vertical roll body center position C _V with respect to the gap center position C _{H is} individually adjusted up and down by the pair of left and right vertical rolls V _R and V _L.

The shape measuring apparatus 10 measures the upper flange leg length a and the lower flange leg length b of the pair of left and right flanges, and the deviation measurement value S of the web center obtained by S = (ab) .1 / 2 is positive. When the value is set, the vertical roll body center position C _V
When the center deviation measurement value S is a negative value, the vertical roll body center position C _V is moved downward.

[Operation] With the above-described structure, the bias measurement values S _R and S _L of the left and right web centers in a predetermined pass in the vicinity of the rough universal mill or the edger mill are obtained, and the bias measurement values S _{R of the} web center are obtained. or if S _L is positive value (deviation below the web) is moved upward vertical rolls V _R or V _L corresponding to the flange, a negative value in the opposite (offset on the web) in this case, the reason the vertical rolls V _R or V _L corresponding to the flange is moved down, to be described later, and eliminates the deviation of the web center in the next pass, a free product unbiased web center from the first rolling Obtainable.

That is, as shown in FIG. 2 (a), when the length of the flange leg on the mill entrance side is a ₀ ≈b ₀ , the contact length L _{f of the} rolled material flange portion with the vertical roll V is L _fa (upper). )> L
_It has been found that the flange leg length on the mill exit side becomes a ₁ <b ₁ when _fb (bottom), and conversely a ₁ > b ₁ when L _fa (top) <L _fb (bottom). Accordingly, as shown in FIG. 2 (b), the upper vertical rolls V _R and V _L with respect to bias measurements of the web center _{S R> 0, S L>} 0 of the rolling material 1 (symmetric) Contact length L _{f of the} rolled material flange to the vertical roll is L _fa (upper)> L
_fb (bottom), the lower flange leg length b ₁ becomes large on the mill exit side, and the symmetric web center deviation is eliminated.

Further, even when the deviation of the web center is difficult to eliminate in the conventional method as shown in FIG. 2C, the pair of left and right vertical rolls V _R and V _L are asymmetrical. It is possible to eliminate the deviation of the center of the web by controlling the movement of the left and right separately. In the example of FIG. 2C, the bias measurement value S _L of the web center (left)> 0, S
_{For R} (right) <0, the left vertical roll V _L may be moved upward and the right vertical roll V _R may be moved downward. In the left flange, L _fa (top)> L _fb (bottom), and the left bottom flange leg length b _L1 on the mill exit side becomes large, and in the right flange, L _fa (top) <L _fb (bottom) As a result, the right upper flange leg length a _R1 on the exit side of the mill becomes large, and the asymmetric web center deviation is eliminated.

Regarding the amount of movement of the vertical roll V, the deviation amount S of the web center in a predetermined pass is measured by a shape measuring device, and the deviation amount S of the web center in the next pass is set to 0 or within a tolerance range by a computing device. Therefore, calculate the vertical roll position,
The vertical roll V is moved up and down by a known elevating method or an elevating method similar thereto to perform rolling. The calculation formula is shown in FIG.
The correlation between the deviation amount S ′ of the web center and the vertical roll body center position C _V (flange pass line) as shown in (d) is obtained by calculation or actual measurement in advance.

The graph of FIG. 2 (d) shows the deviation amount S'of the web center generated when the vertical roll body center position C _V is moved up and down.

Further, in the present invention, the effect of eliminating the deviation of the center of the web can be obtained even by adjusting the vertical roll up and down only once. In particular, in the rough rolling in the rough universal mill, the rolling of the material to be rolled is usually repeated a plurality of times. Therefore, in order to obtain a more effective result, it is preferable to adjust the vertical roll up and down twice or more.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to an embodiment shown in the drawings. This is an example in which the rolling method of the H-section steel of the present invention is applied to a coarse universal mill,
FIG. 1 shows an example of the structure of a coarse universal mill, and FIG. 2 shows an example of an H-section steel production line according to the present invention.

In FIG. 2, a breakdown mill BD, a coarse universal mill UR, an edger mill E, and a finishing universal mill UF are installed in order from the upstream side, and the shape measuring device 10 is provided on the inlet side of the coarse universal mill UR.
And a pair of left and right vertical rolls V _L, V _{R of the} coarse universal mill UR based on the measurement values of the shape measuring device 10.
Each is individually controlled up and down.

As shown in FIG. 1, the coarse universal mill UR has a pair of upper and lower horizontal rolls H arranged in the same plane.
And a pair of left and right vertical rolls V, and the upper and lower horizontal rolls H are rotatably driven by a drive device (not shown) as usual and are supported so as to be able to move up and down by a lifting device. The pair of left and right vertical rolls V _{L and} V _R can be individually lifted and lowered by an elevating device composed of a hydraulic screw 20 and a screw shaft 21 arranged above and below, respectively. Position setting device 1
Controlled by 2.

Since the drive shaft and the roll chock of the horizontal roll H exist above and below the vertical rolls V _{L and} V _R , it goes without saying that the lifting device is arranged so as not to interfere with them. Further, the lifting device is not limited to the above-mentioned structure, and various structures such as a method of lifting by a wedge member can be adopted.

As the shape measuring device 10, an optical shape measuring device such as a non-contact distance meter or an area camera is used, and the upper flange leg lengths a _L, a _R and the lower flange leg lengths of the pair of left and right flanges of the material 1 to be rolled are used. Measure the flange leg lengths b _{L and} b _R. This measured value is input to the arithmetic unit 11, and the arithmetic unit 1
1, the deviation of the left and right web centers S _L, S _R [= (ab) ・
1/2] is calculated, and using the correlation diagram shown in FIG.
Vertical positions of the vertical rolls V _L, V _R corresponding to the respective measured values S _L, S _R are calculated respectively, the moving direction is further determined, each hydraulic screw 20 is operated by the roll position setting device 12, and the left and right vertical rolls are operated. roll V _L, a V _R is vertically moved individually.

Web center deviation measurement S is S _R > 0, S
In the case of _L> 0, the corresponding vertical roll V _R or V _L
By moving up, the contact length L _f of the rolled material flange portion with the vertical roll is set to L _fa (upper)> L _fb (lower), and the lower flange leg length b ₁ becomes large on the mill exit side. (The upper flange leg length a ₀ is large on the mill entry side). Conversely, S
_R <0, in the case of S _L <0, the corresponding vertical roll V _{R
Alternatively} , by moving V _L downward, the contact length L _f of the rolled material flange portion with the vertical roll is changed to L _fa (upper) <L _fb
(Bottom) so that the upper flange leg length a ₁ is large on the mill outlet side (the upper flange leg length b ₀ is large on the mill inlet side).

The H-section steels having the dimensions shown in Table 1 were hot-rolled using the rolling equipment having the above-mentioned configuration, and the occurrence of the deviation of the center at that time was investigated. In this case, the vertical universal roll was controlled up and down in the coarse universal mill.
Further, in a predetermined pass in this rough universal mill, the flange leg lengths of a pair of left and right flanges, that is, four flange leg lengths in total, were measured at the central portion in the longitudinal direction of the material to be rolled. The results (standard deviation 3σ) are shown in Table 1 in comparison with the case of rolling in the comparative example (when the control method of the present invention is not applied).

[0030]

[Table 1]

It can be seen from Table 1 that the deviation of the web center is greatly improved in the present invention. Also, FIG.
The distribution of the deviation amount of the web center in the cross section of the rolled material is shown in FIG. From this figure, according to the method of the present invention, the deviation of the deviation of the web center is significantly improved as compared with the conventional method, and the tendency of the deviation of the left and right web centers in the positive and negative directions is significantly improved. You can see that

Next, Table 2 shows an example of comparison between the conventional method I to the conventional method V and the present invention. The conventional method is the technology disclosed in the section of the conventional technology described above.

Conventional Method I (JP-A-57-97807) Conventional Method II (JP-A-59-144501) Conventional Method III (JP-A-59-193701) Conventional Method IV (JP-A-4- 22501) Conventional method V (JP-A-6-15323)

[0034]

[Table 2]

As is apparent from this table, the conventional method I to
With IV, the effect of suppressing the deviation of the web center is small, and it is difficult to correct the deviation of the web center once generated.

Further, in the conventional method V, although the effect of suppressing the deviation of the center of the web is obtained to some extent, the deviation of the asymmetrical center of the web is corrected only by the upper and lower positions of the center of the gap between the upper and lower horizontal rolls with respect to the center of the vertical roll body. It's hard to be done.

In the above description, the example in which the vertical roll in the coarse universal mill is moved up and down has been described, but it is also possible to apply it to the finishing universal mill.

[0038]

The H-section rolling method according to the present invention is based on the measured values of the deviation of the left and right web centers of the material to be rolled obtained by the shape measuring device installed in the vicinity of the rough universal mill or the edger mill. The vertical roll body center position with respect to the center position of the gap between the upper and lower horizontal rolls of the universal mill is adjusted up and down individually by the pair of left and right vertical rolls, so that the following effects are achieved.

(1) Correcting and moving the web position up and down by moving the vertical roll up and down in the next pass based on the deviation measurement value of the web center in a predetermined pass and changing the contact length of the vertical rolls above and below the flange Therefore, the deviation of the center of the web can be reliably eliminated, and the dimensional accuracy can be greatly improved.

(2) Regarding asymmetrical dimensional defects that are different in the deviation of the left and right web centers, which is difficult with the conventional method,
It can be resolved.

(3) It is possible to eliminate the deviation of the center of the web during rolling, it is possible to fit within the dimensional tolerance from the first die determination, and it is possible to obtain a product with no deviation of the center of the web from the first rolling. Optimal for H-shaped steel rolling with high dimensional accuracy in a small lot.

[Brief description of drawings]

FIG. 1 (a) is a schematic front view showing an example of a universal mill for carrying out the method for manufacturing an H-section steel according to the present invention,
(B) is a schematic plan view showing an example of an H-section steel production line according to the present invention.

FIG. 2A is a side view showing a rolling process of H-section steel by a rough universal mill, and FIG. 2B is a vertical roll body center position (pass line) with respect to a gap center position of upper and lower horizontal rolls of the rough universal mill. A schematic front view showing a contact length model of a rolled material flange portion to a vertical roll, (c) a schematic front view showing a similar left-right asymmetry case, and (d) showing a deviation S of the web center and a pass line. It is a graph which shows correlation.

FIG. 3 is a graph showing a deviation amount S of a web center according to the present invention and a conventional method.

4A is a schematic plan view showing an example of a conventional general H-section steel production line, FIG. 4B is a schematic front view showing a conventional general roll path design, and FIG. It is a schematic side view which shows an occurrence condition.

5A is a schematic front view showing a roll position setting procedure in the conventional method V, FIG. 5B is a cross-sectional view showing a laterally symmetrical web center deviation, and FIG. 5C is a laterally asymmetrical web center deviation. It is sectional drawing shown.

[Explanation of symbols]

BD ... Breakdown mill UR ... Coarse universal mill E ... Edger mill UF ... Finishing universal mill 1 ... Rolled material, 1w ... Web, 1f ... Flange, 10 ...
Shape measuring device, 11 ... Arithmetic device, 12 ... Roll position setting device, 20 ... Hydraulic screw, 21 ... Screw shaft.

Claims (2)

[Claims] 1. When a H-shaped steel is manufactured by rolling a rough-shaped billet having a web and a flange using a rough universal mill, an edger mill and a finishing universal mill, the rough-shaped billet is installed in the vicinity of the rough universal mill or the edger mill. The center position of the vertical roll body relative to the center position of the gap between the upper and lower horizontal rolls of the universal mill is determined based on the measured deviations S _R and S _L of the web center of the left and right flanges of the rolled material obtained by the shape measuring device. A method for rolling H-section steel, characterized in that the pair of vertical rolls are individually adjusted up and down. 2. The method for rolling H-section steel according to claim 1, wherein an upper flange leg length a and a lower flange leg length b of the pair of left and right flanges are measured by a shape measuring device, and S =
(Ab) When the web center deviation measurement value S obtained by 1/2 is a positive value, the vertical roll body center position is moved upward, and when the center deviation measurement value S is a negative value, the vertical A rolling method for H-section steel, which comprises moving the center of the roll body downward.