JPS61255706A - Edger rolling method for sheet material - Google Patents

Abstract

PURPOSE:To increase cross reduction and to improve the yield of a product by providing an expanded diameter part to the lower part of vertical rolls, inclining the rolls in the progressing direction of a rolling material, supporting the bottom end edge of the rolling material atop the expanded diameter part of the rolls and subjecting the material to reduction rolling. CONSTITUTION:The expanded diameter part B is formed to the lower part of a pair of the vertical rolls 11. A housing 10 of a rolling mill is pivotally supported by bearing boxes 12 in such a manner that the housing can rotate freely reversibly. A tilting device 13 is disposed thereto. The axial center of the rolls 1 is made tiltable at a proper angle theta in the progressing direction of the material S by the above-mentioned direction. The top end in the tapered part of the part B in the upright stage is positioned to the part upper than the top surface of a pass line or table roller. The lower part at both side edges of the material S is thereby supported atop the part B and is rolled down. Since the floating on one side of the rolling material is prevented, the cross reduction is increased and the yield of the product is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is an edger for plate materials that rolls rolled materials from the width direction in a thick plate rolling process, a rough rolling process of hot strip rolling, or a blooming process. This relates to a rolling method.

(Prior art) For example, in the rough rolling step of hot strip rolling, the rolled material is rolled to a thickness that can be rolled in a subsequent continuous finishing mill, and then width adjustment rolling is performed to obtain a predetermined product width. will be held. In this width adjustment rolling, that is, edger rolling, a vertical scale breaker (
VSB) Alternatively, when width adjustment rolling is performed using a pair of cylindrical vertical rolls as edgers, if a rolling blade is provided to the rolled material, one side of the rolled material that is in contact with the vertical rolls often lifts up. There is. For this reason, it is not possible to perform sufficient width reduction, resulting in a decrease in dimensional accuracy per width.Also, due to lifting, a step is formed on the side end surface of the rolled material, resulting in a decrease in perpendicularity. (Especially, this one-sided lifting will cause a decrease in the yield rate.)
A quasi-phenomenon occurs in the medium pressure pass, and the floating direction is different for each pass, appearing alternately on the work side and the drive side.

These phenomena will further reduce the width dimension accuracy of the rolled material and worsen the side end shape.
Alternatively, the same phenomenon occurs in edger rolling in the blooming process.

For this reason, various edger rolling methods have been proposed. The first method uses a tapered roll whose diameter expands upward as a vertical roll.

Alternatively, a cylindrical vertical roll may be arranged to be inclined in the width direction (Japanese Patent Laid-Open No. 116259/1983).

Some methods attempt to prevent buckling or one-sided lifting by generating a pressing force against the rolled material during rolling.

In addition, as a second method, there is a method in which a presser roll is used to press the central portion of the rolled material. Furthermore, the third
As a method of rolling, it has been proposed to use caliber rolls as vertical rolls (Special Publication No. 5S-YAZ2).
Publication No.).

(Problems to be Solved by the Invention) However, in the first method, it is not possible to completely prevent one-sided lifting.

The taper of the vertical roll or the inclination in the width direction of the vertical roll reduces the perpendicularity of the side end surfaces of the rolled material.

In addition, although the second method can be considered effective in preventing buckling and one-sided lifting, the rolling equipment becomes complicated and maintenance is difficult. If epithelial scratches occur in the rolled material, the rolled material will collide with the presser roll, which will not only cause damage to the equipment but also impede smooth operation. 1. The purpose of this is to significantly reduce the rolled material to improve the biting quality and reduce the occurrence of slippage, and to prevent the phenomenon of one side lifting when the plate thickness becomes thinner than the caliber dimension. It has the disadvantage that it cannot be used.

As described above, in the various conventional edger rolling methods, it must be said that the buckling phenomenon 1, one-sided lifting, is extremely insufficient for solving multiple phenomena, especially.

The current situation is that no specific solution can be found for the phenomenon of multiple one-sided lifting.

The present invention was made in view of such problems.

In particular, it is an object of the present invention to provide a method for edge rolling a plate material that can suppress the occurrence of the above-mentioned one-sided lifting phenomenon and can achieve a large reduction.

Therefore, the present inventors conducted various analyzes on the phenomenon of one-sided lifting of rolled material during edge rolling, and conducted repeated experiments using a plastitanium model produced by an experimental rolling mill.

As a result, one side of the rolled material often lifts during edge rolling.

(1) Non-uniformity in the shape of the side edges of the rolled material (2) Inclination in the width direction of the rolled material due to the inclination in the width direction of the table roller that conveys the rolled material (3) Vertical rolls of the edger rolling mill It was found that the main cause of this was the inclination of However, multiple phenomena can be resolved.
However, regarding (1), which is caused by the shape of the rolled material, it is necessary to fully understand the behavior of the rolled material caused by the shape of the side edge during rolling.〇The shape of the side edge is as follows:
As shown in Figures 2 to 4, (a) Rolled material (slab)
The rectangularity in the cross-sectional shape of is deformed (Fig. 2),
0) Bulges formed by thickness adjustment rolling (horizontal pass) are formed unbalanced (Figure 3), or (C) Parts of the corners of the rolled material are symmetrically deformed (rolled). (
Fig. 4) When a rolled material with such a side edge shape is edge-rolled, material flow occurs due to plastic deformation of the rolled material due to rolling.〇The amount of material flow in the plate thickness direction Regardless of the shape of the side edge of any rolled material, the portion A in the figure, which protrudes outward, is larger than the portion B.

The reaction of the material flow exerted on the rolled material from the vertical rolls is greater on the part A, and the reaction of the material flow on the shims, corners, and parts B acts as a couple to rotate the rolled material, resulting in the arrow in Figure 1 Rotation of the rolled material in the direction, in other words, lifting of one side of the rolled material will occur.

In order to solve the above-mentioned problems, the present invention is based on the above-mentioned findings, and provides an edger rolling method for plate material in which a rolled material is rolled to a required width by a width reduction stand having a pair of vertical rolls. , a method has already been proposed in which rolling is carried out by tilting the vertical rolls in the direction of progress of the rolled material. That is, in this method, as shown in FIG. Since the vertical rolls 11 are inclined in the direction of movement in a vertical plane parallel to the rolling direction, the motion vector of the vertical rolls 110 in the rotational direction is (due to the vertical component of the force f) is pressed downward against the side edge of the rolled material S by applying force f and pressing the rolled material S downward.

However, in cases where the non-uniformity of the shape at the side edges becomes significant and the amount of reduction becomes large, the above method may sometimes prevent the phenomenon of floating on one or both sides. This may cause one side to rise,
This method was not necessarily sufficient.

Therefore, as a result of further thorough investigation and analysis of the phenomenon and investigation of its causes, the following facts were discovered: O A pair of vertical rolls an and al1 are rolled while running a plate-shaped rolled material (with side edges of a shape) on a table (b) (the direction of travel is from the front side to the back side in the drawing).
Vertical rolls U, U are used to prevent uneven lifting that occurs when the roll is rolled down to the required width by the same roll.
t- Assuming that the rolled material is tilted in advance to the advancing side, the width of the commonly used table α◆ is set smaller than the width of the rolled material. The following moment (b) is generated with point A at the upper end of the table α fathom as a fulcrum.

ld= (F+f) e+ (F-f) (W-tri -------(1) Here, F: Lifting force (or pushing down force) due to the asymmetry of the rolled material f: Pressing due to roll inclination is force W; roll gap e: distance between the end of table 1 and the roll. Therefore, as is clear from equation (1), f=F
Even if the moment of M='lfg acts on the rolled material (S), the phenomenon of floating on one side as shown by the broken line in Figure 1 is likely to occur. However, if f is larger than F, L, ( 1) Formula 1i=Q
It is theoretically possible to prevent the occurrence of "one-sided lift" by controlling the value to approximate "w-zr", such as F'W.However, it is possible to prevent the occurrence of Alternatively, since actual measurement is difficult, it is practically impossible to control the output of the above f-value that corresponds to the true F-number by using the roll inclination.In addition, in the case where the F-number becomes large, the angle of the roll inclination must be set large. This not only makes it difficult to overbite the rolled material and make strong reduction, but also causes a significant downward tilting effect on the roll exit side of the rolled material.

This is undesirable since it increases the risk of deterioration of material quality and operational troubles.

Incidentally, the moment that causes such one-sided lifting can be reduced by increasing the width of the table α◆ to bring it closer to the width of the rolled material, but the width of the rolled material varies depending on the product size, etc. This creates a constraint that makes rolling less than the set table width impossible. This was done with the aim of providing an excellent improvement plan that would reliably prevent the phenomenon of "one-sided lifting" by simply modifying the equipment.

(Means for Solving the Problem) That is, the gist of the present invention is to provide an edge rolling method for rolling a rolled material to a required width (by a pair of vertical rolls), in which an enlarged diameter portion is provided at the lower part of the vertical roll. Provided.

In addition, the vertical roll is tiltable in the traveling direction of the rolled material, and when performing one-width rolling, the vertical roll is tilted in the traveling direction of the rolled material, and both lower edges of the rolled material are expanded in diameter of the vertical roll. The present invention relates to a method of edge rolling a plate material, characterized in that the plate material is rolled down while being supported on the upper surface of the plate material.

(Function) The present inventors have studied various measures to prevent one-sided lifting caused by the generation of a moment with the upper end of the table as a fulcrum as explained in FIG. Focusing on the fact that the bottom surface of the material is in contact with the top surface of the table, which is narrower than the table, is the fundamental cause of moment generation. The present invention was completed based on the idea of making it possible.

Therefore, the content of the present invention will be explained with reference to FIGS. 9 to 10. First, the present invention basically includes a vertical roll α sword having an enlarged diameter portion at the bottom as shown in the figures.

This enlarged diameter portion (B) has a truncated truncated cone shape and is formed by an upper tapered portion 0 and a lower straight portion (b). However, the rolled material is supported by the enlarged diameter part Φ)K. Edger rolling is performed with the lower edges of both sides of the rolled material supported on the upper surface of the tapered part (a). At the same time, in the example of Fig. 9, a table α is placed directly under the vertical rolls
◆ indicates the case where the rolled material (S) is supported only by the rolls without using the table.

The tapered portion (a) serves as a guide to improve the biting of the rolled material into the roll, and it is advantageous to provide it.

There is no problem even if the enlarged diameter part is composed of only the straight part 0.

Of course, it is also possible to configure it with only the tapered portion (a).

By providing the vertical rolls on both sides with the function of supporting the rolled material, point A, which serves as a fulcrum for moment generation, as shown in FIG. 9, is moved to the side edge of the rolled material.

When l=O in the above equation (1), the moment (b) at this time is drastically reduced to the value of the following equation.

M =: (F −f ) W −−−−−−−−−(
2) Therefore, by assigning a specific minimum f to F by the roll inclination, the value of equation (2) becomes 0, and it is possible to effectively suppress the floating of the pieces.

Furthermore, it is not necessary to match f due to the roll inclination exactly to the value of F, and by selecting f larger than F with some margin, it is possible to obtain the same result.

This is because, if f) is F, the moment will be a negative value from equation (2), but the side end of the rolled material will move downward due to the support reaction force at the support point () of the expanded diameter part of the roll circle. This is because, since it is restrained, there is no need to worry about one side floating up on the opposite side.

Next, Fig. 10 shows an example in which the present invention is applied as usual without removing table a4. In this case, roll αI) (b) is The vertical relative position between the enlarged diameter portion (B) and the table σ in the upright state is adjusted in advance. A level difference is provided between the tabs and the tapered portion (a) so that the upper end of the tapered portion (a) is at least slightly above the upper end of the table a4.

Then, as shown in the same figure ←), roll α11(2)
In the tilted state, the point (A') is the supporting point of the rolled material) and the point (A') moves upward, so the support by the table is released and the rolled material is supported only by the rolls, similar to Fig. 8. situation.

The premise of the present invention is that the inclination of the rolling rolls is as shown in Fig. f89 and Fig. 10, as shown in Fig. f89 and Fig. 10. It is very simple and there is no need for detection of one piece of sheet lifting and no control based on this, which is very preferable from a practical point of view.

FIG. 1 shows an actual example of a vertical rolling mill applied to the present invention. To further explain the present invention, a rolling mill housing 10 is reversibly rotatably supported by a bearing box 12. ,
Although the illustration is omitted, a pair of vertical rolls 11 having an enlarged diameter portion ( ) at the bottom are mounted so as to be movable in the width direction of the rolled material S by a rolling mechanism similar to that of a conventional vertical rolling mill. A tilting device 13 is provided to tilt the rolling mill housing 10 so that the vertical rolls 11 are tilted at an appropriate angle θ in the direction of movement of the rolled material S. That is, in the case of the illustrated example, trunnion cylinders 13B, 13b are installed at the lower ends of both sides of the housing 100 as the tilting devices. Cylinder 13 and located on the advancing side according to the advancing direction of the rolled material
The housing 10 is tilted and rotated twice by an appropriate angle θ by synchronously operating the rod on the opposite side of the moving direction and retracting the rod on the opposite side to the direction of movement. When the direction of progress of the rolled material is reversed, the rod of the cylinder 13b is contracted and at the same time the cylinder 11 is extended and tilted to the opposite side by an appropriate angle -0.

(Example) The present inventors conducted a model experiment using plastitanium under the following conditions, and confirmed the effect of preventing one-sided lifting of rolled material according to the present invention (Fig. 11) .

Vertical roll material Gypsum roll Vertical roll shape ■Roll with a lower diameter enlarged part (taper part angle 14°) ■Flat roll (conventional type) Vertical roll diameter 129mmφ Rolled material material Plasticine rolled material size Plate thickness 20 mm, @l [ 159m
m, plate length 250mm Rolled material shape Side end face inclination angle 5° (Fig. 12) Rolling
Lower amount IQmm Vertical roll inclination angle 5° inclination to exit side g.

Table width IQQmm Rolling temperature 0℃ Rolling speed 3 m/min The amount of one-sided lifting is measured at the tail end of the rolled material when the inclination angle of the 90 vertical roll is 0°, that is, when the conventional vertical roll is used.
When flat rolled, the A side in Figure 12 rose by 53 mm.

Also, when the vertical roll is tilted by 50 degrees in the direction of travel.

When flat rolled, the A side in Figure 12 rose by 3Qmm.

On the other hand, in the case of the present invention, that is, when both vertical rolls are inclined at 5 degrees in the direction of travel and a roll with a lower diameter enlarged portion is used, one side lifting hardly occurs and the dogbone part of the rolled material does not lift up. There was only a problem.

(Effects of the Invention) According to the present invention, it is possible to use a special detection and control means for the phenomenon of one-sided lifting, which is a big problem in width rolling, by using a relatively simple equipment configuration such as providing an enlarged diameter section at the bottom of the vertical roll. This can be easily and reliably prevented, making it possible to achieve a large width reduction with high precision, and also to minimize the amount of selvage cut off after rolling).

It provides excellent effects such as greatly contributing to the improvement of product yield, and its industrial value is extremely large.

[Brief Description of the Drawings] Fig. 1 is a side view showing an example of a rolling mill applied to the edger rolling method of the present invention, Fig. 2 is an explanatory diagram showing a conventional edger rolling state, and Figs. The figure is a cross-sectional view showing the cross-sectional shape of a rolled material, Figures 6 to 10 are explanatory diagrams showing the principle of edger rolling, and Figure 11 is an illustration of the effect of preventing one-sided lifting based on an experimental example of the present invention. The graph and FIG. 12 each show a perspective view of the rolled material used in the experiment.

Claims (1)

[Claims] In an edger rolling method in which a rolled material is rolled to a required width using a pair of vertical rolls, the vertical rolls are provided with an enlarged diameter section at the bottom and are tiltable in the direction of movement of the rolled material. A method for edger rolling a plate material, characterized in that during rolling, the vertical roll is inclined in the direction of movement of the rolled material, and the rolled material is rolled down while supporting both lower edges of the rolled material on the upper surface of the enlarged diameter part of the vertical roll.