JPS6264402A - Continuous rolling mill train - Google Patents

Abstract

PURPOSE:To prevent the buckling and slip of a material and to make an installation smaller and simpler in a hot rolling line for rolling a bloom of steel products to a billet by alternately arranging a driving horizontal rolling mill group and non-driven vertical rolling mill group. CONSTITUTION:The horizontal rolling mill group 10 consisting of two units of driving horizontal rolling mills 1 is arranged on both sides of the vertical rolling mill group 20 consisting of two units of non-driven vertical rolling mills 2. This continuous rolling mill train indicates basic constitution and many variations are possible. The group 20 is thereby made extremely small in size and housings can be so made as to contact with each other. The distance between the axial centers of the respective rolls of the rolling mills 1, 2 is made as small as possible in order to permit the rolling reduction similar to the case in which the rolling mills 2 are of a driving type. The material is then rolled by the group 10 and is pushed into the group 20 by the thrust thereof. The generation of buckling in the extrusion rolling stage is considerably less as compared with the conventional driving type in the case of the same reduction rate of area. The generation of the slip of the driving rolls can be considerably decreased by increasing the number of the driving rolling mills than the number of non-driven rolling mills.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a rolling mill row for rolling billets as raw materials for various Bloomin products made of steel or the like.

(b) Prior Art For example, in the rolling of long steel, continuous casting bloom sound is usually used. Continuously cast blooms are bloomed into billets at a blooming factory, and after reheating, the billets are rolled into various products at a bar factory or wire rod factory.

As shown in FIG. 7, a conventional rolling mill in a blooming plant is generally a continuous rolling mill row in which horizontal rolling mills 1 and vertical rolling mills 2 are arranged alternately. in this case.

Both horizontal and vertical rolling mills are driven. Steel bar factory/
The same applies to wire rod factories.

Here, the horizontal rolling mill 1 has a configuration in which a pair of work rolls are arranged parallel to the width direction of the rolled material, sandwiching the front and back surfaces 7 of the rolled material and applying rolling force in the thickness direction of the rolled material. What is happening? The vertical rolling mill 2 has a configuration in which a pair of work rolls are arranged perpendicularly to the surface of the rolled material, sandwiching the longitudinal sides of the rolled material and applying a rolling reduction of 7 in the width direction of the rolled material. Beg. Here, when the rolling mill is driven, it means that the work rolls are rotationally driven.

Since the vertical rolling mill requires a work roll drive device f to be installed in the upper part of the rolling mill housing, the equipment cost is more than three times that of a horizontal rolling mill with the same power. For this reason, the height of the rolling building increases, each rolling mill also requires 5 m or more, and the length of the rolling building increases.

Not only the rolling mill-related costs (but also the building-related construction costs) will increase.

In order to eliminate the above-mentioned drawbacks, the present applicant has proposed
1. Publication No. s7°203 (% Application No. 57-70208:
1 proposes that in a continuous rolling mill row in which horizontal rolling mills 1 and vertical rolling mills 2 are arranged alternately, the vertical rolling mills 2 are not driven, as shown in FIG. but,
If only the vertical rolling mill 2 is not driven, the rolled material will buckle in both the driven horizontal rolling mill 1 and the non-driven vertical rolling mill 2 on the downstream side.

It becomes difficult to continue rolling. Therefore, the area reduction rate in the non-driven vertical rolling mill 2 is set to be 66 times less than the area reduction rate in the upstream driven horizontal rolling mill 1.

In this case, the overall reduction in the thickness direction by the horizontal rolling mill 1 is nearly twice the overall reduction in the width direction by the vertical rolling mill 2, and when trying to obtain a square billet or product, the material has a square cross section. cannot be used, so a rectangular cross section with a large degree of flatness must be used.

On the other hand, quality requirements for materials for long steel are strict, and reduction of nonmetallic inclusions and center segregation is a particular issue. Making the material into a flat rectangular cross-sectional dimension, such as the cross-sectional dimensions of the continuously cast bloom, does not allow for boring, which increases center segregation. Current general bloom cross-sectional dimensions are 300+ thick
The width ranges from 300 mg in width to 300 m in thickness and 400 mm in width. When using such a nearly square bloom, it is difficult to apply the technology of the above-mentioned patent application to the current rolling process.

(c) Problems to be solved by the invention The problems to be solved by the invention are to prevent material buckling and slipping by alternately arranging horizontal rolling mill groups and vertical rolling mill groups, and to By making the rolling mill group non-driving, the equipment can be made smaller and simpler, and at the same time, it is possible to obtain an area reduction rate Y equivalent to that of the conventional drive system.

B) Means for Solving the Problems The continuous rolling mill train of the present invention alternately operates a plurality of driven horizontal rolling mill groups and a plurality of non-driven vertical rolling mill groups in a hot rolling line for steel materials. By arranging them, the above problem is solved.

Embodiment 9 FIG. 1 is a plan view showing the basic configuration of a continuous rolling mill row according to the present invention. This basic continuous rolling mill row has a configuration in which a horizontal rolling mill group 10 consisting of two driving horizontal rolling mills 1 is arranged on both sides of a vertical rolling mill group 200 consisting of two non-driving vertical rolling mills 2. .

2 to 4 show modifications of the basic configuration shown in FIG. 1, respectively.

In FIG. 2, a horizontal rolling mill group 10 is made up of three horizontal rolling mills 1.

In FIG. 3, a horizontal rolling mill group 10 is made up of four horizontal rolling mills 1.

In FIG. 4, a horizontal rolling mill group 0 and a vertical rolling mill group 20 are each made up of four horizontal rolling mills 1 and four vertical rolling mills 2.

In the continuous rolling mill row of the present invention, the vertical rolling mill group 20 is very compact and is constructed in such a way that the housings are in contact with each other.

For further rolling, the vertical rolling mill 2 is not driven, and in order to enable the same rolling reduction as in the case of driving, the roll axis of the driven horizontal rolling mill 1 into which the rolled material is pushed.

The distance between the roll axis of the non-driven vertical rolling mill 2 into which the rolled material is pushed is kept as small as possible.

(to) action The operation of the continuous rolling mill train of the present invention will be explained.

The material is rolled in the first horizontal rolling mill group IO.

The propulsive force pushes it into the non-driven vertical rolling mill group 20. Since the distance between the roll axes is much smaller than in the conventional drive system, the occurrence of buckling during indentation rolling is significantly reduced compared to when the area reduction ratio is the same. Further, by increasing the number of driving rolling mills to a greater number than the number of non-driving rolling mills, the occurrence of slip in the driving rolls can be significantly suppressed.

The material leaving the non-driven vertical rolling mill group 20 will be drawn off by the following driven horizontal rolling mill group 10.

In this case, a tensile force acts on the material, and whether or not it can be rolled is determined by whether slip occurs in the drive horizontal rolling mill group 10.

Prevention of slipping can be easily solved by increasing the contact area Z between the work roll and the rolled material, making the roll surface rough, and increasing the coefficient of friction between the roll and the rolled material. In particular, the use of a box hole type or simply restraining the side surfaces of the rolled material increases the anti-slip effect.

- As an example, horizontal/vertical work roll diameter Di=300
+x, the thickness of the rolled material at the exit side of the horizontal rolling mill di = 45 to 105 (d i /D i = 0.15 to 0.35), and the distance between horizontal and vertical workpiece and roll axes Li = 1300 mm.

715 Dragon (Li/D! = 4.33, 2.38), rolling temperature is 1100℃, and when rolling is performed on a rolled material of low carbon killed steel, the area reduction rate in the driven rolling mill and the area reduction rate in the non-driven rolling mill are The relationship between ya and the area reduction rate is shown in FIGS. 5 and 6, respectively. FIG. 5 shows the case of a conventional continuous rolling mill in which the vertical rolling mill is not driven, and FIG. 6 shows the case of the continuous rolling mill of the present invention.

In the case of a conventional rolling mill with Lt = 130 (htz (Li/Di = 4.33)), the area reduction rate in the vertical rolling mill is about 70 times that of the horizontal rolling mill (Figure 5). , 1=715
In the case of Tomo's (Li/Di=2.38) rolling mill of the present invention,
This is possible up to 100% (Figure 6).

(g) Specific Examples The continuous rolling mill row of the present invention shown in FIG. 1 was constructed as follows, and rolling 7 was carried out.

Number of stands: 26 stands 1st. π2. 5th and 6th stands S1, S2, S5, S
6: Drive horizontal rolling mill (LH, 2H, 5H16H) 3rd,
4th stand 83. S4: Non-driven vertical rolling mill (3V, 4V) Work-roll axis distance Li (3V-4V): 450
*π Total length of continuous rolling mill: 4. sm Horizontal/vertical work/roll outer diameter Di: 600vx/250mtz Rolled material thickness di between adjacent stands: 90-70 Sin Bloom (starting material): Thickness 120m :
Table 1 Table 1 The configuration and rolling results of a conventional continuous rolling mill are shown below for comparison. Other than the description below, the description is the same as above.

Li: 700jll 1-V) Continuous rolling/machine total length: 5. om Billet (finished product): thickness 120 wx Can not. In other words, when the material becomes smaller due to buckling, only light reduction is possible.

On the other hand, in the continuous rolling mill row of the present invention, as can be seen from Table 1, the number of stands is at least one compared to the conventional technology.
A reduction in surface area equivalent to that of the vertical (v) stand drive system is obtained.

According to the present invention, since the vertical rolling mill is non-driven, the entire equipment can be made smaller and the cost can be reduced, and it is possible to realize a rolling pattern that is substantially the same as that in the case of a driven rolling mill, so that it can be applied to various rolling mills. .

[Brief explanation of drawings]

FIG. 1 is a plan view showing the basic configuration of a continuous rolling mill row according to the present invention. 2 to 4 are plan views showing another modification of the continuous rolling mill row of the present invention. FIG. 5 is a graph showing the relationship between the area reduction rates of drive and non-drive rolling mills in conventional continuous rolling mills. FIG. 6 is a graph showing the relationship between the area reduction rates of drive and non-drive rolling mills in the continuous rolling mill of the present invention.
The figure is a plan view showing a row of conventional continuous rolling mills. l: Horizontal rolling mill 2: Vertical rolling mill 10: Horizontal rolling mill group 20: Vertical rolling mill group Patent applicant: Sumitomo Metal Industries, Ltd. Figure 4 Figure 7 Figure 8

Claims (1)

[Claims] A continuous rolling mill row, in a hot rolling line for steel materials, characterized in that a plurality of driving horizontal rolling mill groups and a plurality of non-driving vertical rolling mill groups are arranged alternately.