JPS6033802A - Rolling mill - Google Patents

Abstract

PURPOSE:To obtain a rolling method having excellent effects on intense draft performance and shape and sheet-profile control, etc. by using a variable crown roll and a roll provided with a shiftable intermediate roll for backup rolls and arranging respective rolls specifically, in a cluster mill. CONSTITUTION:In a cluster mill as shown by a figure, a variable crown backup roll 2 is used in combination with a backup roll 1 provided with a shiftable intermediate roll. And the rolls 2, 2 and 1, 1 are arranged vertically on the diagonal lines respectively. Thus a rolling method having excellent effects on the requests of intense draft performance, shape and sheet-profile control, investment cost, and operation performance, etc., is obtained. Further, the rolling method is made more effective by making the work rolls of said mill smaller in diameter as well as making their peripheral speeds different from each other and forming further the backup rolls with intermediate rolls into variable crown ones.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rolling method that significantly enhances the crown shape control effect.

Comparing the advantages and disadvantages of recent rolling methods, each has considerable advantages, but they also have their own drawbacks. Therefore, it is desired to develop a rolling method that is superior in terms of performance, equipment, operation, etc.

Among various rolling methods, variable crown roll (hereinafter referred to as
It's called VC role. ) has been shown to be relatively effective in meeting various requirements. However, even this method had some drawbacks in terms of control performance and performance under strong pressure.

Next, Table 1 shows a comparison of the advantages and disadvantages of typical conventional rolling methods.

Table 1 In Table 1, HC mill refers to the workpiece and
This is a new 6-layer rolling mill that has an intermediate roll between the roll and the backup roll, and by shifting the intermediate roll in the axial direction, changes the deflection of the work piece and controls the crown and shape of the copper strip. .

The P-mill controls the crown and shape of the copper strip by reducing the rolling load component caused by friction during rolling by varying the circumferential speeds of the upper and lower work rolls.

The NMR mill is a combination of a conventional four-layer rolling mill and a Sendzimir multi-stage mill, which enables strong rolling reduction and a high degree of crown and shape control.

An object of the present invention is to obtain a rolling method that exhibits excellent effects on at least all of the items listed in Table 1.

The basic idea of the present invention is to use a combination of a VC roll and a shiftable backup roll (with an intermediate roll) as a backup roll in a cluster mill in order to control the shape and plate profile under strong pressure. be.

Further, by developing this idea, it is possible to reduce the diameter of the work roll and incorporate different circumferential speed rolling to improve control performance. Further, regarding the VC roll, the pressure chamber can be divided into a plurality of parts in the longitudinal direction, and these VC rolls can be appropriately combined to perform appropriate shape control.

In rolling mills in which multiple rolls circumscribe the circumference of one roll at the same time (for example, cluster mills, Sendzimir mills, etc.), a VC roll and a backup roll with a shiftable intermediate roll are used as the circumscribing rolls, and small-diameter workpieces and By combining the effects of rolling at different circumferential speeds, the crown shape control effect can be significantly enhanced. The combined effect of both rolls is greater when small diameter work rolls are used. Even for strong rolling, it is more effective to use a combination of small-diameter work rolls and rolling at different circumferential speeds. The mill can also be used as a scale breaking mill, and scale breaking can be done more effectively than conventional mills.

As the diameter of the work roll becomes smaller, the deflection of the roll becomes VC.
It becomes easier to follow the swollen shape of the roll. Therefore, by introducing a different type of VC roll (one with a different number of pressure chamber compartments in the longitudinal direction) and giving it a complex roll deflection that was previously impossible, we have significantly improved the shape, plate profile, and strong pressure control function. can be improved.

Next, an example of the rolling method of the present invention will be described.

<Example 1> (1) Rolling line: Hot rolling line (2) Rolling base material dimensions: Thickness 35m1 + width 1200mm ×
Weight: 25 tons (3) Mill used: Cluster mill (Fig. 1 (4) or (1) applicable to the first stand of finishing mill) (4) Work roll: Small diameter variable circumferential speed roll (5) Backup mill Roll: VC roll, with shiftable intermediate roll and backup roll (Fig. 1 (4) or CB)) (6) First stand reduction rate 75% (7) Effect: Compared to rolling with a normal 4-layer mill The rolling load was reduced to less than 1/4, and in addition to improving the strong rolling performance, the crown shape control ability was doubled.

A Actual flow side 2〉 (1) Rolling line: Cold rolling line (2) Rolling base material dimensions: Thickness 3.8 viILX width 125
0 Tomiguro x Shigei 45 ton (3) Mill used: Cluster mill (applied to the first stand of tandem mill) (4) Work roll: Small diameter different circumferential speed roll (5) Backup four-wheel: No. VC roll 1 and heterogeneous VC roll 2 shown in FIG. 3 were used. The VC roll 1 has no partition in the pressure chamber 11, and the different type VC roll 2 has the pressure chamber 12 divided into two in the longitudinal direction. These VC rolls 1 and 2 are used in a roll arrangement as shown in FIG.

(6) 1st stand rolling reduction near 5% (7) Effects: ■ When only C roll 1 is used, the shape of the rolled material only changes from ear wave to medium elongation, and medium elongation occurs near the weld. It cannot be treated when stretch and ear waves occur together. However, when the VC roll 1 and the different types of VC rolls 2 were used, the crown shapes of both became K as shown in FIG. 4, so that when the VC roll 2 was operated, the middle elongation and ear waves were also eliminated. When the different type of VC roll 2 was further worked under good rolling conditions, quarter elongation (elongation that occurs in the vicinity of about 1/4 from both grades in the width direction of the rolled material) occurred. From this, it is possible to conversely control quota growth.

<Example 3> (1) Rolling line: cold rolling line. The first stand was configured as the mill of Example 1 (Figure 1), and the second stand was configured as the mill on the actual flow side 2 (Figure 2).

(2) Rolling base material dimensions: thickness 4.5 m x width 11000
r x weight 40 ton (3) First and second stand rolling reduction ratio 285% (4) Effect: Conventionally, the material thickness was 2.3 mm, and the finished product thickness was 0.5 mm.
However, in this example, a material with a thickness of 2.8 mm could be rolled to a finished product with a thickness of 0.8 mm. ♂5 oath ・0 strong pressure reduction is now possible.

Entrance side small of 1st and 2nd stand Diameter workpiece: Nominal @, 1oo due to the influence of the roll.

The board profile is 17μ, Edge drop improved by 18μ In addition to the Quota growth plummets and remains largely flat Improvements were made.

[Brief explanation of drawings]

1 and 2 are schematic explanatory diagrams of embodiments of the present invention. FIG. 6 is a schematic explanatory diagram of a VC roll applied to the method of the present invention. FIG. 4 is a graph showing the crauchi shape of the VC roll shown in FIG. 6. 1: VC roll 2: Different types of VC rolls 11.12: Pressure chamber Patent applicant Sumitomo Metal Industries, Ltd.

Claims (4)

[Claims] (1) In a cluster mill, a pick-up roll (a vine-up roll with a variable crown roll and a shiftable intermediate roll) is used, and the individual rolls are arranged diagonally up and down. rolling method. (2) The method according to claim 1, characterized in that, in the mill, work rolls are made smaller in diameter and configured to have different circumferential speeds, and rolling at different circumferential speeds is incorporated. (3) The variable crown roll can be replaced with a different type of variable crown roll.
A method according to claim 1, characterized in that it is configured in a roll and incorporates shape profile control. (4) The pick-up roll with the shiftable intermediate roll is configured as a variable crown roll or a different type of variable crown roll, and incorporates shape profile control. the method of.