JPS602921B2 - Manufacturing method of shaped steel with protrusions - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a section steel having a large number of protrusions on the outer surface of a flange.

Shaped steel is rarely used alone in architecture and civil engineering structures, but is often used in combination with concrete.

In that case, rather than using the section steel and concrete as separate structural members, it is advantageous in terms of strength to use them as a so-called composite member that is joined together. In order to integrate the section steel and concrete, they need to be tightly connected to each other. However, in reality, the adhesion force between the two members is less than 4.0, and integration cannot be expected as it is. Therefore, as shown in the example of a composite beam structure, the current method is to press shear connectors such as studs and dowels onto the H-shaped steel flange that contacts the concrete slab, and then bend them to tightly connect the two. I am teaching. By forming a large number of protrusions on the outer surface of the flange of a section steel by rolling, the section steel itself can have a binding force with concrete, making it possible to simplify the member and significantly improve construction. BACKGROUND OF THE INVENTION Hitherto, lining plates have been known as H-shaped steel having protrusions on the outer surface of the flange, which are used for the purpose of covering the ground during road construction.

However, the surface protrusions of the lining board are intended to prevent slipping of vehicles, etc., and are not intended to create a tight bond with concrete. For lining boards, the height of the protrusions is not very necessary, and is usually 1.5 to 2. It is about the level of an enemy, and the protrusion angle is less than 400. According to research conducted by the present inventors, the height of the protrusion must be 2.5 mm in order to obtain the striped effect with Kuncrete.
It is necessary that the angle of the protrusion is 45 degrees or more.

Furthermore, in the case of lining plates, even if the area of the indentation is small, it is sufficient to achieve the purpose, but in order to increase the bonding force with the concrete, the area of the protrusion must be need to be less than 1/8 of the total. When manufacturing steel sections with such protrusions using conventional methods, various problems occur.
The newly raised problems will be explained using a section steel rolling line as an example.

A typical H-beam rolling line consists of a heating furnace 1, a breakdown mill 2, and a rough universal mill 3, as shown in the figure.
1 and an Etziya mill 32 in a tandem arrangement, and a finishing universal mill 4. Ru. In order to form protrusions on the outer surface of the flange, in the finishing universal mill 4, a large number of recesses may be provided on the outer surface of the vertical roll that rolls down the outer surface of the flange. In order to form a protrusion height comparable to that of a conventional lining board, the reduction amount must also be 1.5 to 2. Since a slight reduction is sufficient, this is approximately the same as the amount of reduction during normal finish rolling. In order to increase the height of the protrusion, it is sufficient to increase the amount of reduction of the flange thickness in the finishing universal mill, but this causes the problem of roll up action as shown in FIG.

The roll-up action causes the protrusion shape to collapse.
The reason for this is that since the vertical roll is idle, the flange advances greatly, and the material speed Vs is larger than the roll circumferential speed VR on the roll exit side, and the once formed protrusion shape becomes pores near the roll exit side. This is because it interferes with the mold and is rubbed up, causing the shape to collapse toward the bottom in the rolling direction. Also,
Since it is necessary to increase the area to be recessed compared to the lining plate, the flange thickness reduction ratio becomes larger, and the flange advance ratio tends to become even larger. As a second problem,
The problem is that the height of the protrusion becomes uneven in the width direction of the flange.

Taking H-beam steel as an example, FIG. 3 exaggerates this phenomenon of uneven protrusion height. When a vertical roll is provided with a large number of recesses, the apparent coefficient of friction during rolling of the outer surface of the flange increases, and metal flow in the width direction of the flange increases. The closer you get to the flange end, the greater the influence of this widthwise metal flow, and as a result, the protrusion is pulled down.
On the other hand, at the center of the flange, the height of the protrusion is lowered by a smaller amount due to the restraint of the web. In this way, as shown in the figure, the height of the protrusion in the width direction of the flange becomes non-uniform. Therefore, it is an object of the present invention to provide a method for manufacturing a shaped steel with projections that eliminates deformation of the shape of the projections due to roll-up action.

Another object of the present invention is to provide a method for manufacturing a shaped steel with projections that eliminates deformation of the shape of the projections due to roll-up action and eliminates uneven height of the projections in the width direction of the flange.

The method of the present invention improves the hole shape of the vertical rolls of a finishing universal mill to prevent the protrusion shape from collapsing due to the rolling up action.

Yet another method of the present invention is to improve the vertical roll profile of the finishing universal mill and increase the jet reduction of the coarse universal mill group.
Alternatively, by increasing the taper angle of the vertical roll of the rough universal mill, not only the deformation of the protrusion shape but also uneven protrusion height in the flange width direction can be prevented.

First, a method for preventing the first problem, the deformation of the protrusion shape due to the roll-up action, will be explained. The deformation of the protrusion shape occurs because the protrusion interferes with the hole mold near the roll exit side due to the advancement of the flange and is slid up. The flange advance is given by the ratio (v2/vR) between the material speed v2 on the roll exit side and the roll circumferential speed (vR).
Now, as shown in Fig. 4, assuming that the web and flange are separated, and ignoring the widening of the flange at the neutral point, the material speed and roll circumferential speed are The neutral point N where these coincide is located at the center of the contact length. Therefore, the flange advance rate ■F is the following 0
It is expressed by one equation. ■F=V2/VR-・=v2/Vn-
・ ...(1, however, v2: Material speed at the roll exit side vn: Material speed at the neutral point vR: b...
- Peripheral velocity (=vn) Under the condition of constant volume, the above equation '11 can be expressed as the following equation (2).

■F=An/n-1=tfn/tr2-1...
■However, An: Material cross-sectional area at the neutral point trn: Material plate thickness at the neutral point A2: Material cross-sectional area at the roll exit side tr2: Material plate thickness at the roll exit side On the other hand, the material plate thickness trn at the neutral point is calculated using the following formula t31 tfn = 1/4 (tn + 2) ... [3
}However, tf is the material plate thickness on the roll entry side.

Therefore, the advanced rate ■F is approximately expressed by the following equation [4']. Hai's trX magazine ni 0.25 (no t goju no t mineju no t character)...[41 However,? tr is the flange thickness reduction rate.

Figure 5 shows the flange reduction rate tf and the flange advance rate ■
It is a graph which shows the experimental result which calculated|required the relationship with F. This experimental result almost agrees with the above equation {41] regardless of the rolling equilibrium between the web and the flange. That is, it can be seen that in H-section steel rolling, the flange advancement rate ■F is approximately proportional to the flange thickness reduction rate tr. . Next, we will discuss material lifting using flange advancement and roll hole type.

FIG. 6 is an enlarged and exaggerated view of the roll hole portion shown in FIG. 2. P is the position where the roll leaves the material on the roll exit side.
, the foot of the perpendicular line at the center of the roll is Q, and distance QP=〆R, then R is expressed by the following equation {5'. 〆R=no wave vhd
-h cost...■ However, Rv: Roll radius hd: Protrusion height The distance s that the material travels while the roll moves is s=
There is a relationship between ZR (10 ■F) and Nowa Rokuichi (10 ■F).

If the angle of collapse of the protrusion due to the sliding action is Q, tanQ is given by the following equation {61 with reference to FIG. 6.
SoS-SoR tanQ=-Down-=〆Zero (Shuuki)...'6} From the above side, the collapse of the protrusion shape is due to the flange advance rate■F
It can be seen that it is proportional to .

Therefore, if you try to manufacture a section steel with a large protrusion height, the flange thickness reduction ratio tf will be large, and the flange advance rate ■F will also be large according to the above formula '41, and the collapse of the protrusion shape will increase according to the above formula ■. I understand that.

From the above equation (2), it is clear that if the flange advance rate (2) F is made as small as possible, the deformation of the protrusion shape will also be reduced.
However, as long as the vertical roll is idle, the flange advance rate ■F cannot be controlled as given by equation (4).Therefore, the vertical roll of the finishing universal mill was driven to satisfy the following equation '7]. In this case, the material speed on the roll exit side and the roll circumferential speed match, and the protrusion shape does not collapse due to the roll sliding action.

NV=k The conventional method is idle, and it is necessary to attach a rotary drive device to the vertical roll, which complicates the mechanism of the finishing universal mill and increases the cost of modification.
As long as it is based on the use of existing equipment, it is not very practical.

Therefore, as a result of extensive experiments and research, the present inventors found that
By improving the hole shape attached to the vertical roll,
We discovered that even when the vertical rolls are idle, the roll-up effect can be kept to a minimum.

Figure 7 shows the hole shape (solid line) attached to the vertical roll,
The resulting protrusion shape (two-dot chain line) is shown.

In the figure, the arrow indicates the rolling direction, 8 indicates the taper angle on the top side of the groove in the rolling direction, 82 indicates the taper angle on the bottom side, R
is the rounding radius of the top side of the groove in the rolling direction, R is the radius of curvature of the top side curved surface of the groove in the rolling direction, and the shaded area is the radius of the top side of the groove in the rolling direction.
Each figure shows the raised part. As can be seen from Fig. 7, the roll up action is greatly influenced by the hole shape of the top example in the rolling direction, and the smaller the taper angle 0 on the top side in the rolling direction, and the larger the rounding radius R, the more the roll up action. becomes smaller.

On the other hand, in order to increase the bonding force with concrete, the protrusion angle needs to be 45 degrees or more.

After repeated experiments taking these conditions into consideration, we found that it is preferable for the taper angle of 0 and the radius of roundness R to be within the following range.

500 ≦0, ≦600 ○-003RV<R<○-009RV Although some deformation of the protrusion shape due to rolling action is inevitable, in order to ensure the symmetry of the protrusion shape in the rolling direction, rolling It is necessary to change the hole shape on the bottom side of the direction from the hole shape on the top side.

For this purpose, the Taber angle of the hole on the bottom side in the rolling direction is 02.
500 or less, and process the rounding radius to be larger than the top side. Therefore, the method of the present invention is characterized in that the shape of the hole is changed between the top side and the bottom side in the rolling direction in anticipation of the roll-up action. Even if the hole shape is an arc, as shown in FIG. 7F, the roll-up action can be suppressed.

In this case, in order to obtain an appropriate protrusion shape, the hole shape on the top side in the rolling direction is preferably within the following range.
1.0kR. <2.0kR O. 00 class v < R < 0.00 class v The shape of the hole on the bottom side in the rolling direction must be set so that the taper angle 82 is 600 or more by predicting the deformation of the material in advance.

Ultimately, the basis of the hole shape based on the method of the present invention is
Although the shapes shown in FIGS. A and B are suitable, the shape shown in FIG. 8C or D, which is a suitable combination of these shapes, may also be used.

In addition, when applying the method of the present invention, in order to suppress flange advance to a maximum of 4.5 mm, it is desirable that the flange thickness reduction ratio be as small as possible, as long as the height of the protrusion is guaranteed. next,
A method for preventing the second problem, non-uniform protrusion height in the flange width direction, will be explained.

Figure 9 shows the flange thickness reduction ratio (tf) and protrusion height ratio (
2 is a graph showing the results of an experiment to find the relationship between The protrusion height ratio is the protrusion height hs of the material divided by the roll hole depth hR. In the figure, the white circle (0) mark indicates the center of the H-section steel flange, the triangle (△) mark indicates the end of the flange, and the black circle (●) indicates the half position from the center to the end of the flange. represent. As can be seen from FIG. 9, the protrusion height ratio increases in proportion to the flange thickness reduction ratio, but in the case of H-beam steel, the protrusion height ratio becomes less pronounced at the ends.

This is because the protrusion height at the flange ends is lowered by the metal flow caused by the widening of the flange width, whereas the center part receives compressive stress in the rolling direction due to the restraint of the web, and the protrusion height tends to increase. In order to make the protrusion height uniform, it is sufficient to increase the flange thickness reduction rate, but for the reasons described later,
It is desirable that the flange thickness reduction ratio be as small as possible. Rather,
By locally increasing the rolling reduction of the flange weave, it is possible to achieve a uniform protrusion height without significantly increasing the rolling reduction of the entire flange. Therefore, in the method of the present invention, in order to form a uniform protrusion height in the flange width direction, the rolling of the flange end is reduced by appropriately changing the vertical roll shape of the rough universal mill or by changing the rolling pass schedule. locally increases.

First, as one method, the reduction of the flange weave can be locally increased by modifying the vertical roll outer surface taper of the rough universal mill as shown by the two-dot chain line in FIG. The side surfaces of the horizontal rolls and the outer circumferential surface of the vertical rolls of the rough universal mill are tapered by 4-10 mm mainly for reasons of roll consumption. In the method of the present invention, the flange thickness reduction rate in the finishing universal mill is increased toward the ends by further increasing the taper angle of the vertical rolls in the roughing universal mill. The vertical roll modification amount is 120 mm for a flange width of 20 mm, and 10 lo for a flange width of 30 mm, which is sufficient to achieve the purpose. However, if this method were to be effective on its own, the taper angle would become too large, which would interfere with normal H-section steel rolling. In order to locally increase the amount of reduction at the flange end, this can also be achieved by simply changing the rolling pass schedule without modifying the roll shape.

The normal coarse universal mill is paired with the edger mill. The Jeziya mill rolls down the flange end,
Works to align the flange width. It is already well known that when a flange weave is rolled in a edger mill, the flange is deformed into a cocoon shape as shown by the two-dot chain line in FIG. 11 because the flange shape is vertically long. Therefore, another method of the present invention actively utilizes this cocoon-shaped deformation to increase the subcutaneous amount of the flange end using a finishing universal mill.

FIG. 12 is a graph showing the results of an experiment to determine the relationship between the edging reduction rate (edge) and the flange layer increase rate (-tr).

Here, when the rate of increase/decrease in flange thickness is expressed as logarithmic strain, if the decrease in thickness is taken as positive, the increase in thickness will be negative. In order to standardize the symbols, the flange thickness increase rate will be expressed as "1 tf".
Note that the flange thickness reduction rate (tf) is usually 0.1 to 0.
5 (10% to 50%), and the flange thickness increase rate (1 tr) is usually 10.05 to 10.15 (10% to 50%).
-5% to 15%). In the figure, the white circle (0) represents the maximum flange thickness (trMx), the triangle (△) represents the minimum flange thickness (tfmin), and the black circle (●) represents the flange average thickness (tf). The increase in flange thickness increase rate - elongation is proportional to the edging reduction rate of 8, and the larger the edging reduction rate OB, the greater the increase in tf of the flange thickness increase rate. However, when the edging reduction ratio E becomes 0.1 or more, the flange portion buckles and rolling becomes unstable. The edging reduction rate before finishing in the normal H-shaped steel rolling process is approximately 8 = 0.01 to 0.02, but in order to make the protrusion height uniform, it is necessary to increase the plate thickness at the flange end. According to the results of studies conducted by the inventors, the edging reduction ratio E needs to be 0.05 or more. Therefore, another method of the present invention is to use an edger before finishing universal mill.
By appropriately selecting the edging reduction ratio E of the mill in the range of 0.05 to 0.10, the wall thickness of the flange end can be locally increased and finished, and the height of the protrusions attached to the flange can be made uniform using a universal mill. can be achieved. That’s all, Part 2
Two methods were explained to solve the problem. Although sufficient effects can be obtained using these methods alone, even greater effects can be obtained by combining both methods. Furthermore, in order to solve the first problem and the second problem at the same time, by appropriately combining each method, it is possible to obtain a synergistic effect that cannot be obtained with a single method.

Next, as an example, a specific embodiment based on the present invention will be shown.

Examples> Target shape steel: Japanese steel (450 x 200 x 9/14) Projection shape: 4.5 square x height 3 (side) Projection pitch: 16 x 16 (
side) Hole shape: 8, = 600, H2 = 4y R = 0.008Rv Pass schedule: By the above rolling conditions, the height of the protrusion in the flange width direction is uniform, and the protrusion shape ( A protrusion angle of 57o, height 3 side) could be formed on both flange sides.

Although the above explanation has been made by taking H-section steel as an example, the method of the present invention can also be applied to other section steels that can be finished with a universal mill.

The hole shape in that case may be different depending on the difference in the technology. As is clear from the above explanation,
According to the method of the present invention, the protrusion strengthens the bonding force with concrete, equalizes the height of the protrusion in the flange width direction, minimizes the roll up action, and guarantees a protrusion angle of 45o or more. It is possible to form a section steel.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a conventional H-beam rolling line. FIG. 2 is a schematic explanatory diagram showing the roll-up action. FIG. 3 is a schematic explanatory diagram showing nonuniform protrusion height in the flange width direction.
FIG. 4 is an explanatory diagram for theoretically determining the relationship between the flange thickness reduction rate and the flange advancement rate. FIG. 5 is a graph showing the experimental results for determining the relationship between the flange thickness reduction ratio and the flange advance ratio. FIG. 6 is an explanatory diagram showing an enlarged and exaggerated view of the roll hole shape shown in FIG. 2. FIG. 7 is an explanatory diagram showing the relationship between the hole shape and the protrusion shape attached to the vertical roll. FIG. 8 is an explanatory diagram showing a roll hole pattern based on the method of the present invention. FIG. 9 is a graph showing the experimental results for determining the relationship between the flange thickness reduction rate and the protrusion height rate. FIG. 10 is an explanatory diagram showing an example of modifying a vertical roll of a rough universal mill. FIG. 11 is an exaggerated view showing how the edge of the flange is deformed into a cocoon shape by the edger mill. FIG. 12 is a graph showing the experimental results for determining the relationship between the edging reduction rate and the flange thickness reduction rate. 1...Heating furnace, 2...Breakdown mill, 3...Roughing universal mill group, 4...Finishing universal mill, 3
1...Coarse Universal Mill, 32...Jeziya Mill. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Leopard-10 Figure 11 Figure 12

Claims (1)

[Claims] 1. A hole pattern attached to the outer peripheral surface of a vertical roll of a finishing universal mill when forming a protrusion with a protrusion height of 2 mm or more and a protrusion angle of 45° or more on the outer surface of a flange of a section steel using a universal mill. 1. A method for manufacturing a shaped steel with protrusions, characterized in that the shapes are formed into mutually different shapes depending on the location in the rolling direction, and the finally obtained protrusion shape is prevented from collapsing. 2. When forming a protrusion with a protrusion height of 2 mm or more and a protrusion angle of 45° or more on the outer surface of the flange of a section steel using a universal mill, the rolling reduction ratio φ_E of the Edger mill in the rough universal mill group should be set to 0.05<φ_E. <0.10
By selecting from the range of , the wall thickness of the flange end is locally increased, and the groove shape attached to the outer peripheral surface of the vertical roll of the finishing universal mill is formed into a different shape depending on the location in the rolling direction. A method for producing a shaped steel with protrusions, characterized in that the final protrusion shape obtained is uniform and does not collapse. 3. When forming a protrusion with a protrusion height of 2 mm or more and a protrusion angle of 45° or more on the outer surface of a flange of a section steel using a universal mill, the taper angle of the outer peripheral surface of the vertical roll of the coarse universal mill should be adjusted according to the flange width of the product. 1-2
The thickness of the flange is increased toward the ends by increasing the thickness in the angular range of °, and the groove shape attached to the outer peripheral surface of the vertical roll of the finishing universal mill is formed into a different shape depending on the location in the rolling direction. A method for manufacturing a shaped steel with projections, characterized in that the shape of the projections finally obtained is uniform and does not collapse. 4 When forming a protrusion with a protrusion height of 2 mm or more and a protrusion angle of 45° or more on the outer surface of the flange of a section steel using a universal mill, the rolling reduction ratio φ_E of the edger mill of the rough universal mill group should be set to 0.05<φ_E. <0.10
The taper angle of the vertical roll outer surface of the rough universal mill should be selected from the range of 1 to 2 depending on the flange width of the product.
The thickness of the flange is increased toward the ends by increasing the thickness in the angular range of °, and the groove shape attached to the outer peripheral surface of the vertical roll of the finishing universal mill is formed into a different shape depending on the location in the rolling direction. A method for manufacturing a shaped steel with projections, characterized in that the shape of the projections finally obtained is uniform and not distorted. 5. In the method described in any one of claims 1 to 4, the hole shape has a hole taper angle θ_1 on the top side in the rolling direction of 50°≦θ_
1≦60°, and the rounding radius R is 0.003R_V<R0
．． 008R_V (where R_V is the vertical roll radius), and the taper angle θ_2 of the hole on the bottom side in the rolling direction is 50
A method for producing a shaped steel with protrusions, characterized in that the shape is selected within the following range. 6. In the method set forth in any one of claims 1 to 4, the groove shape is such that the slope of the groove on the top side in the rolling direction is shaped like a downward arc;
Its radius of curvature R_1 is 1.0h_R<R_1<2.0h
_R (however, h_R is the depth of the hole), and the rounding radius R on the top side in the rolling direction is 0.003R_V<R<0.00
8R_V (where R_V is the radius of the vertical roll), and the taper angle θ_2 of the hole on the bottom side in the rolling direction is selected to be within a range of 60° or less.