JP2749698B2 - Control method of profile and plane shape of rolled plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial application field" The present invention relates to a method of preheating a rolling roll to roll a rolled plate, and a profile (rolling pressure distribution in a width direction) of the rolled plate.
And a method of controlling a planar shape (flatness).

2. Description of the Related Art There is known a technique of rolling a rolled plate by preheating a rolling roll by a preheater, an induction heating coil, a heat pipe, or the like, and reaching a required amount of heat crown of the roll.

[Problems to be Solved by the Invention] In the preheating of the roll in the conventional technology, it is a problem whether or not the amount of the heat crown to be applied has reached a required amount, and the shape of the heat crown has not been a problem. Therefore, accurate control for obtaining a rolled plate having a desired profile and a desired planar shape has been extremely difficult.

An object of the present invention is to provide a control method that can easily produce a rolled plate having a desired profile and a desired plane shape in a method of rolling a rolled plate by preheating a roll.

"Means and Actions for Solving the Problems" The inventors completed the present invention from the viewpoint that as a result of various experiments, the heat crown shape of the roll due to the preheating of the roll has an important effect on the profile and planar shape of the rolled plate. It was done. That is, the method for controlling the profile and plane shape of a rolled sheet according to the present invention achieves the above-mentioned object, and predicts the occurrence of 1/4 elongation of the rolled sheet with respect to the heat crown amount of a portion corresponding to the width of the target rolled sheet. The profile and plane shape of the rolled sheet are selected by appropriately selecting the ratio of the amount of heat crown of the portion corresponding to the interval between positions.

In FIG. 2, the distance between points a and a indicates the length of the rolling roll, the horizontal straight line b indicates the surface of the rolling roll, and the arc-shaped line c indicates the distribution of the heat crown amount of the rolling roll during preheating.
Now, the heat crown amount of a portion corresponding to the width W of the rolled plate before rolling, which is smaller than the lengths a to a of the rolling roll, is represented by d, and the 1/4 elongation of the rolled plate (from the end in the width direction of the rolled plate by rolling, 1 of width
/ 4 or less, the portion close to the center extends in the length direction to generate a wave, and a plane shape defect phenomenon) Assuming that the heat crown amount of the portion corresponding to the interval l between the predicted positions is e, the heat with respect to the heat crown amount d The ratio of the crown amount e, ie, e / d
As a result, a certain correlation is recognized between the amount of the rolled sheet and the profile and planar shape of the rolled sheet, and the value of the ratio e / d (hereinafter referred to as “the crown shape factor k”) is appropriately determined. , The profile and plane shape of the rolled plate rolled by the rolling rolls can be controlled.

More specifically, by setting the crown shape factor to 0.4 or more and 0.6 or less, it is possible to roll a rolled plate having an intermediate profile as shown in FIG. Rolled plates can be manufactured. Further, by setting the crown shape factor to less than 0.4, the profile of the rolled sheet can be made into a W shape as shown in FIG. 1 (b), and the plane shape can be made into a 1/4 shape state. it can. Further, by setting the coefficient to a value exceeding 0.6, the profile of the rolled sheet can be M-shaped as shown in FIG.
The planar shape can be formed as an ear extension and a middle extension (hereinafter referred to as “ear / medium extension”).

The crown shape factor can be appropriately set according to the preheating temperature and other preheating conditions. When heating the central portion of the rolling roll, if the heating temperature and other conditions are the same, the crown shape factor is large when the heating width is small, and conversely, the crown shape factor is small when the heating width is large.

"Example" By the preheating, the heat crown amount d of the rolling roll in the portion corresponding to the width of the rolled plate and the predicted position of the 1/4 elongation of the rolled plate (in this embodiment, approximately 1/4 of the width from the edge of the plate) /
The heat crown amount e of the portion corresponding to the interval between the four centers (approximately 4 positions closer to the center) is selected, and a different crown shape factor k is set for each case, and rolling (see Cases 1 to 9 in Table 1) is performed. Table 4 shows the profiles and plane shapes of the rolled plates of each of the cases 1 to 9 when a four-stage three-tandem rolling mill for aluminum hot rolling was used.

The rolled plates in Cases 1 to 9 are made of an aluminum alloy (JIS1050).

In the "planar shape" of Table-2, "1/4 elongation" is a state where about 1/4 of the width from the side edge of the plate generates a wave and extends in the length direction from other parts. , "Ear stretch" is a state in which the plate side edge generates a wave and extends in the length direction from other parts, and "Medium stretch" is a state in which the central part generates a wave and extends in the length direction from the other part. It is in a stretched state.

According to the results in Table 2, since there is a certain correlation between the crown shape factor k of the rolling roll, the profile of the rolled plate, and the plane shape of the rolled plate, the profile of the rolled plate is set by setting the crown shape factor k to 0.4 to 0.6. In addition to the intermediate type, the planar shape of the plate can be made flat. Also,
If the crown shape factor k is less than 0.4, the profile of the rolled sheet becomes W-shaped, and the sheet plane shape shows a 1/4 elongation tendency. Further, if the crowning shape factor is set to 0.6 or more, the profile of the rolled plate becomes M-shaped, and the plate planar shape shows a tendency of ear and middle elongation.

The crown shape factor k is also closely related to the heating width when the method of heating the central portion of the rolling roll is used. FIG. 3 shows the relationship between the width of the rolled sheet and the crown shape factor using the heating width of the roll as a parameter.
(The heating width is narrow) and B (the heating width is wide).

As is clear from the results of FIG. 3, an appropriate heating width can be selected by introducing the crown shape factor.

The method of the present invention can be carried out not only on aluminum and its alloys but also on rolling metals such as copper and its alloys and iron.

[Effects of the Invention] According to the method for controlling the profile and plane shape of a rolled sheet according to the present invention, by appropriately selecting the shape of the heat crown at the time of preheating the roll, the desired profile and the desired plane shape of the rolled sheet are obtained. Is easier to select.

[Brief description of the drawings]

Fig. 1 (a), (b) and (c) are cross-sectional views showing the profile of the rolled plate, and Fig. 2 shows the heat crown amount of a portion corresponding to the width of the rolled plate in the roll and the prediction of the occurrence of 1/4 elongation. FIG. 3 is a conceptual diagram showing a relationship between a heat crown amount corresponding to an interval between positions, and FIG. 3 is a diagram showing a relationship between a crown shape factor k and a rolled plate width when a heating width of a roll is used as a parameter. is there. Description of the reference numerals in the main drawings a to a is the length of the roll, b is the surface of the roll,
c is the distribution of the amount of heat crown, w is the width of the rolled plate, l is 1 /
4 The distance between the elongation occurrence predicted positions, d is the heat crown amount of the roll in a portion corresponding to the width of the rolled plate, and e is
The amount of heat crown of the roll corresponding to the interval between the predicted 1/4 elongation occurrence positions, and k is e / c (crown shape factor).

 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Hiroshi Nagakura 2-6-1 Marunouchi, Chiyoda-ku, Tokyo Inside Furukawa Aluminum Industry Co., Ltd. (56) References JP-A-52-13455 (JP, A) 52-34027 (JP, B2)

Claims (2)

(57) [Claims] In a method of rolling a rolled sheet by preheating a rolling roll, a portion corresponding to an interval between predicted positions of 1/4 elongation occurrence of a rolled plate with respect to a heat crown amount of a portion corresponding to a width of the rolled plate. A method for controlling a profile and a planar shape of a rolled plate, wherein a profile and a planar shape of a rolled plate are selected by appropriately selecting a ratio of a heat crown amount. 2. The rolling ratio is selected by selecting a value of less than 0.4 to make the profile of the rolled plate M-shaped and the plane shape to be a 1/4 elongated shape, and selecting a value of 0.4 or more and 0.6 or less. The profile of the plate is set to the intermediate type and the planar shape is flat, and the profile of the rolled plate is W-shaped by selecting a value exceeding 0.6, and the planar shape is the ear / medium elongated shape. The method for controlling a profile and a planar shape of a rolled sheet according to claim 1.