JP3419017B2 - Rolling method for H-section steel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION The present invention relates to a universal rolling mill.
Unavoidable when hot rolling H-section steel using
Minimize fluctuations in flange thickness in the vertical and horizontal directions
Trying to do it. [0002] 2. Description of the Related Art Hot rolling equipment for H-section steels is known as break down.
Rolling mill, coarse universal rolling mill, edger rolling mill,
And finishing universal rolling mill (Fig. 3
a, b), slabs and blue
Materials such as beams and beam blanks (see Fig. 4a, b, c)
Are sequentially passed and are rolled to obtain a predetermined cross-sectional dimension.
Shaped steel is manufactured. [0003] Breakdown rolling mill in the above equipment
Has multiple open or closed holes along the roll drum
Double pressure with upper and lower rolls (see FIGS. 5a and 5b)
It is a rolling mill, where a rough shaped slab of H-section is rolled.
Is done. [0004] Coarse Univers with Horizontal and Vertical Rolls
In a rolling mill, which is obtained by breakdown rolling.
The rolling of the crude slab is further advanced, and the horizontal roll
The roll in its thickness direction with a horizontal roll and a vertical roll.
The flange is pressed down in its thickness direction (see FIG. 6a),
The flange width is used in combination with a coarse universal rolling mill.
Is reduced to the specified size by the edger rolling mill
(See FIG. 6b). [0005] The above rough rolling is performed until a predetermined cross-sectional dimension is reached.
Repeated multiple times, then finish universal rolling mill
At the end of the process (see FIG. 6c). [0006] In the hot rolling of the H-section steel according to such a procedure,
Is a pair of horizontal rolls at the top and bottom and a pair of vertical rolls at the left and right
A rolling mill with straight rolls is used.
During rolling, a rolling reaction force acts on each roll, which causes
Since each part of the rolling machine is elastically deformed, the roll gap during rolling is
It increases compared to the roll gap at no load. Web, web
Under the conditions of normal rolling reduction to reduce the flange, after rolling,
The thickness of each part and the size of the roll gap for rolling the part
There is no problem because they are the same, but the roll gap during rolling is
If the value becomes inappropriate, the thickness after the pass rolling differs from the target value.
In general, especially in rough universal rolling.
Since multiple passes are rolled, dimensional fluctuations in one pass
Is the disturbance of the dimensions before rolling in the next pass,
This has caused a decrease in dimensional accuracy. Further, in recent years, there has been a demand for a thin-walled H-section steel.
It is important to reduce the residual stress or reduce the shape.
From the viewpoint of preventing the occurrence of good quality, the cooling rate is lower than that of web.
During the hot rolling of the flange or at the end of the final stage
Later, water cooling may be forcibly performed.
If the flange thickness is not uniform, the temperature of the steel material will be uneven.
Troubles such as uneven cooling and shape defects
was there. [0008] Regarding the control of the roll gap during rolling,
It has been studied, and as a representative one, Iwayu
There is setup control. This is usually the rolling reaction
The amount of increase in the roll gap caused by the gap is linear
Prediction of the rolling reaction force (rolling load), and
Try to adjust the roll gap at no load in advance
Things. The literature on this point includes Universal
Adjust the gap between horizontal and vertical rolls of the rolling mill
63-1 to control flange and web thickness
No. 04714, JP-A-63-123510
Referenced. [0009] The actual H-shape
Variations in roll clearance during universal rolling of steel
Not only those caused by the rolling reaction force of
Some may be due to gap setting accuracy or mechanical play.
These factors greatly affect the dimensional accuracy of H-section steel.
Well, simply applying the prior art as described above, up and down left
The flange thickness on the right can be made uniform
There was no current situation. [0010] Especially when placed on a universal rolling mill
Relative error in the axial direction of the lower horizontal roll (no thrust
Has a very large effect on dimensional accuracy. That
In the case of universal rolling of H-section steel,
Between the roll side and the vertical roll in the thickness direction
Where the horizontal roll thrust
When the roll occurs, the width of the roll is
In the opposite direction to the change in the roll gap in the roll, the other
The roll gap will change (see Fig. 7).
As a result, the flange thickness at the top, bottom, left and right of the H-section steel
Was to fluctuate (see FIG. 8). [0011] Such a variation in the thickness of the flange is caused by each flange.
This causes a difference in the reduction rate in the
Leg length at flange (web to flange width direction)
(Dimensions up to the end)
The center position in the direction is shifted from the center position of the web thickness.
Cause of eccentricity (hereinafter simply referred to as center eccentricity)
(See FIG. 9). In this regard, the horizontal row at the top and bottom
The amount of misalignment in the axial direction of the
It is conceivable to correct the positional deviation, but the horizontal
If the tools are shifted in the same direction,
The gap with the vertical roll will also fluctuate (Fig. 10, Fig.
11)), consider the positional relationship with such a vertical roll.
Especially the end face of the horizontal roll.
In the case of a coarse universal rolling mill with an inclination angle
It is difficult to adjust the gap between each roll.
At present, no attempt has been made to deal with
Low quality due to poor flange thickness accuracy and center deviation
Had to be forced down. [0013] The hot rolling of an H-section steel as described above
To solve such problems, especially in the vertical and horizontal directions
Propose a new method that can achieve uniform thickness
It is an object of the present invention. [0014] SUMMARY OF THE INVENTION The present invention provides a universal
In the rolling process using a rolling mill, each flange
Measure the thickness of the
The relative position error of the flat roll in the axial direction
Relative error of roll opening of vertical roll, or vertical and horizontal
What is the relative error of the roll opening
The flange thickness is uniform
The gap between each roll quickly according to these errors.
I am trying to correct it. That is, the present invention provides a breakdown rolling
The rough shaped steel slab having an H-shaped cross section obtained by applying
Coarse universe with roll axis position adjustable for each pass
When rolling using a monkey rolling mill,
In rolling, heat placed close to the rough universal rolling mill
Reduce the thickness of the coarse billet flange with the gap measuring device.
Are measured at four locations, up, down, left, and right.
Roll axis of the upper and lower horizontal rolls of the coarse universal rolling mill
Direction deviation, roll opening for left and right vertical rolls
Deviation and the vertical and horizontal roll center
Calculate the deviation of the straight roll from the roll drum center position,
Position of each roll where these deviations are 0 or within the allowable range
After the position change, the coarse billet is
-It is characterized by rolling in one pass or more through a monkey rolling mill
This is a method for rolling an H-section steel. [0016] [Function] Thickness of at least four flanges, up, down, left and right
Measurement of the gap between each roll (hereinafter simply referred to as
(Referred to as the amount of shift), and how to correct this amount of shift
This will be described below. Placed on universal rolling mill
Of the horizontal rolls, when the lower horizontal roll is
Δ in the roll axis direction of the upper horizontal roll
T, with reference to the vertical roll on the working side (OP side)
In the direction of the roll axis of the vertical roll on the drive side (DR side)
The deviation in the perpendicular direction is ΔV,
The amount of deviation of the center of the horizontal roll gap from the center
Is shown in FIG. Where
The angle of inclination at the roll end face of the roll
Measured with a hot dimension measuring device placed on the entrance or exit side
Above the OP side, below the OP side, above the DR side, below the DR side
The thickness of each flange₁, t_Two, t_Three, t
_FourIn addition, the horizontal and vertical
Each roll gap is T₁, T_Two, T_Three, T_Four,
Further, the flange thickness when ΔT = ΔV = ΔH = 0 is
T₀Roll of vertical roll caused by ΔH as
If the change between is ΔC, [0017] (Equation 1)           T_i= T_i/ Cos θ (i = 1,2,3,4) --- (1)           T₁= T₀+ ΔT + ΔC --- (2)           T_Two= T₀−ΔC --- (3)           T_Three= T₀−ΔT + ΔV + ΔC --- (4)           T_Four= T₀+ ΔV-ΔC --- (5) Therefore, [0019] (Equation 2)           T₀= (T₁+ 3T_Two+ T_Three−T_Four) / 4 --- (6)           ΔC = (T₁−T_Two+ T_Three−T_Four) / 4 --- (7)           ΔH = ΔC / tan Θ --- (8)           ΔT = ｛(T₁−T_Two) − (T_Three−T_Four)｝ / 2 --- (9)           ΔV = T_Four−T_Two                              ---(Ten) [0020] That is, there is a pass with a coarse universal rolling mill.
After finishing the process, use the hot dimension measurement device to
At least four flange thicknesses t₁, t_Two, t_ThreeAnd
And t _FourAnd correct them by the angle of inclination, and
By determining the gap in the vertical direction, the above (7),
Using the equations (8), (9) and (10),
The deviation amount of the rule gap can be obtained. At the time of rolling the material to be rolled,
If there is a gap between the horizontal and vertical rolls,
Since you are absorbed by the rolling reaction,
Deviation from the zero point (reference position) becomes dominant
It is thought that there is. Therefore, almost the same error will occur after the next pass.
There is a concern that a difference (roll gap error) may occur.
You. To make the thickness of the four flanges of the material to be rolled uniform
Is a draft correction that cancels such a roll shift
(Change the position of each roll and correct any)
It is necessary. Here, the horizontal roll of the universal rolling mill
The radius of R_H, The radius of the vertical roll is R_V,
The property constant is M and the mill stiffness of the horizontal roll in the rolling direction is K._H,
The mill stiffness of the vertical roll in the rolling direction is K_VOf a horizontal roll
Mill stiffness in the roll axis direction is K _TThen, up and down, left and right
Flange thickness t_fAnd target flange thickness T
_fTherefore, considering the mill rigidity by the following formula,
The amount of deflection ΔT, ΔV, ΔC is set for each roll without load.
Correction amount ΔS_T, ΔS_Y, ΔS_HConvert to This place
Between the amount of roll deviation correction and the roll deviation during rolling
Equation f₁, f_Two, f _Three, f_FourIs calculated in advance or measured
Use the one you have reserved. [0023] (Equation 3)   ΔS_T= F₁(M, K_T, t_f, T_f, R_H, R_V) ・ ΔT… (11)   ΔS_V= F_Two(M, K_T, t_f, T_f, R_H, R_V) ・ ΔV… (12)   ΔS_H= F_Three(M, K_T, t_f, T_f, R_H, R_V) ・ ΔH… (13) In addition, there is an error (shift) in the set position of the roll.
Flange thickness t₀Is the target value of the path
It is also possible that they differ by Δt,
With the same concept as thickness control, between no-load vertical rolls
Interval correction amount ΔS_fThe roll opening of the left and right vertical rolls
To correct. [0025] (Equation 4)   ΔS_f= F_Four(M, K_T, t_f, T_f, R_H, R_V) ・ Δt… (14) Roll set at the time of rolling in the next pass (rolling
Reaction force), and for the left and right vertical rolls
S_VOP, S_VDRAnd the upper and lower horizontal rolls are S_HU, S_HL, Up
Horizontal roll thrust S_HTAnd deviation in these
If the correction amount is taken into account, the setting roll gap (^*With a
The gap that takes into account the deviation correction amount is expressed by the following formula.
You. [0027] (Equation 5) S_VOP ^*= S_VOP−ΔS_f              … (15) S_VDR ^*= S_VDR−ΔS_f-ΑΔS_V    … (16) S_HU ^*= S_HU-ΑΔS_H                … (17) S_HL ^*= S_HL+ ΑΔS_H                … (18) S_HT ^*= S_HT-ΑΔS_T                … (19) The amount of deviation between these roll gaps is
Make roll settings that cancel each other, and basically follow the next pass
It is better to erase everything with
All corrections may result in shape defects
In consideration of the relaxation coefficient α (0 ≦ α ≦ 1),
It is effective to correct it. In the hot rolling of the H-section steel, the hot dimension
To measure the flange thickness of the material to be rolled with a method measuring instrument,
For example, it is disclosed in Japanese Patent Application No. 3-2933582.
Such a measuring method is advantageously adapted. Measuring flange thickness
The result measures at least one point in the longitudinal direction of the material to be rolled.
However, when measuring at multiple points, the end of the rolled material
By averaging data near the center excluding the area,
The thickness of each flange can be a representative value
You. FIG. 2 shows a pressure suitable for carrying out the present invention.
1 shows a schematic diagram of a rolling mill, in which 1 is a breakdown rolling mill,
2 is a coarse universal rolling mill, 3 is an edger rolling mill, 4
Is a finishing universal rolling mill, 5 is a coarse universal rolling
The hot dimension measuring device shown in the example arranged on the entrance side of the machine 2, 6 is
An arithmetic unit, the arithmetic unit 6 comprising a hot dimension measuring device 5
Roll based on the flange thickness measured in
Calculate the amount of gap, and then repair the roll gap in the next pass
Calculate the positive quantity. 7 is a roll of the coarse universal rolling mill 2
A gap setting device, which is calculated by the calculation device 6
The result is input to the device 7, where it is set in advance.
Is added to the specified next pass roll gap, and
The horizontal roll clearance, thrust position, and vertical roll of the next pass.
Rule is set. Roll roll position as above
The alignment is performed at least once during rolling of the material to be rolled,
This makes it possible to achieve uniform flange thickness.
You. In the example shown in FIG. 2, a hot dimension measuring device is used.
5 for both the edger mill 3 and the coarse universal mill 2
Upstream of the coarse universal rolling mill group consisting of
At the entrance of the versal rolling mill).
But accurately measures flange thickness after rough rolling
If possible, the location should be a coarse universal pressure.
There is no problem even on the exit side of the mill or downstream. Ma
In addition, the present invention relates to a row mill incorporated in a universal rolling mill.
To eliminate asymmetry in each gap
Therefore, for the next material to be rolled in which almost the same conditions continue
It is also effective in rolling, and is the result of rolling the material to be rolled?
The roll clearance required from the
Rolling the rolled material will further improve the dimensional accuracy
Is advantageous. Tolerance when correcting roll gap
The value of the relaxation coefficient α is adjusted according to the progress of the rolling pass.
Then, an appropriate value may be used. A machine for adjusting a horizontal roll of a rolling mill in an axial direction.
Regarding the structure, the universal rolling mill for H-section steel
What is disclosed in Japanese Kokai Hei 3-24301,
What is necessary is just to adopt the method similar to. [0033] [Embodiment] Applying the equipment shown in FIG.
Continuous 460 mm, flange width 400 mm, web thickness 120 mm
Using beam blank (steel type: SS400) obtained by casting
Nominal dimensions: 600 mm web height, 300 mm flange width
Hot rolled H-section steel and adjust the flange thickness at that time.
Inspected. In this example, the rough universal rolling (
Pass after the flange thickness has been measured
Measure the central part in the longitudinal direction of the material to be rolled)
The position was adjusted. The result (standard deviation σ) is
Contrast with the conventional method (when the position of the roll is not changed at all)
The results are shown in Table 1. [Table 1]As apparent from Table 1, according to the present invention,
H-beam flange thickness variation is reduced and dimensional accuracy is reduced.
It was confirmed that it was useful for improvement. [0035] Thus, according to the present invention, the heat of the H-section steel
Position of the universal rolling mill used during cold rolling
Minimize dimensional defects caused by placement fluctuations
be able to.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing a state where the arrangement positions of respective rolls of a universal rolling mill are shifted. FIG. 2 is a diagram showing a configuration of equipment suitable for implementing the present invention. FIGS. 3A and 3B are diagrams showing a configuration of a hot rolling facility for H-section steel. FIGS. 4 (a), (b), and (c) are diagrams showing the cross-sectional shapes of H-shaped steel blanks. FIGS. 5 (a) and 5 (b) are diagrams showing a groove shape of a breakdown rolling mill. 6A is a diagram showing a cross-sectional shape of a material to be rolled in rough rolling, FIG. 6B is a diagram showing a cross-sectional shape of a material to be rolled in edger rolling, and FIG. FIG. 3 is a view showing a cross-sectional shape of a material to be rolled in FIG. FIG. 7 is a diagram showing a state of rough rolling. FIG. 8 is a diagram showing a change state of rolls of a universal rolling mill. FIGS. 9 (a) and 9 (b) are views showing a state of center deviation. FIG. 10 is a view showing a situation in which horizontal rolls of a universal rolling mill are equally displaced in the roll axis direction both vertically and vertically. FIG. 11 is a view showing a situation where upper and lower horizontal rolls of a universal rolling mill are both displaced in a direction (downward) perpendicular to the roll axis. [Description of Signs] 1 Breakdown rolling mill 2 Rough universal rolling mill 3 Edger rolling mill 4 Finishing universal rolling mill 5 Hot dimension measuring device 6 Arithmetic device 7 Clearance setting device 8 Breakdown rolling mill 9 Rough rolling mill 10 Edger rolling mill 11 Finishing mill 12 Slab 13 Bloom 14 Beam blank 15 Opening type 16 Closed type 17 Horizontal roll 18 Vertical roll 19 Edger roll 20 Horizontal roll 21 Vertical roll

Continued on the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B21B 37/16 B21B 1/08 B21B 13 / 10,13 / 12 B21B 31/16

Claims (1)

(57) [Claims 1] A coarse universal slab having an H-shaped cross section obtained by performing a breakdown rolling, wherein the position of the horizontal roll in the roll axis direction can be adjusted for each pass. When rolling using the rolling mill, when rolling the coarse shaped steel slab, the thickness of the flange of the coarse shaped steel slab is adjusted at least up, down, left and right by a hot dimension measuring device arranged close to the coarse universal rolling mill. From the measurement results, the deviation of the roll axial position of the upper and lower horizontal rolls of the rough universal rolling mill, the deviation of the roll opening between the left and right vertical rolls, and the center of the roll gap between the upper and lower horizontal rolls, Calculate the deviation of the vertical roll from the center of the roll cylinder, change the position of each roll so that these deviations are within zero or within an allowable range, and after this position change, remove the crude steel slab from the coarse universal rolling mill. Rolling method of H-beams, characterized by rolling in one pass or more through.