JPH0436761B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rolling method using a multi-high rolling mill having a function of controlling the shape of a rolled material.

In recent years, in order to improve the thickness shape and precision of the rolled material in the width direction, various methods have been implemented for bending work rolls that come into contact with the rolled material in multi-high rolling mills, for example, 4- to 6-high rolling mills. A typical example of this is explained based on FIG. 1. This is a four-high rolling mill, which has vertical roll bending devices 1 and 1', and which bends the rolls according to changes in the width of the rolled material 2. A pair of upper and lower work rolls 3, 3' movable in the roll axis direction and a pair of back-up rolls 4,
It consists of 4'. Therefore, by moving the upper and lower work rolls 3 and 3' in opposite directions in the roll axis direction in accordance with the width of the rolled material 2, and bending the work rolls, the ability to modify the shape by roll bending is improved. The aim is to make full use of it. FIG. 2 shows a conventional six-high rolling mill, in which intermediate rolls 5, 5' are provided between the upper and lower work rolls 3, 3' and back-up rolls 4, 4', respectively, in the conventional rolling mill. Further, the intermediate rolls 5 and 5' are configured to be movable in the roll axis direction according to the width of the rolled material 2, respectively. Therefore, depending on the width of the rolled material, the intermediate rolls 5 and 5' are arranged so that their long ends match the both ends of the rolled material, or slightly inside the both ends of the material (with the width of the material) as shown in the figure. center side) (-
HCδ), and as in the case of the conventional example, the shape accuracy of the rolled material in the width direction is improved by moving the work rolls 3, 3' in the axial direction and using the roll bending devices 1, 1' together. The aim is to improve this even further.

3 and 4 show a 5-high rolling mill consisting of upper and lower work rolls 6, 7, upper and lower back-up rolls 8, 8', and an intermediate roll 9 provided between the upper work roll 6 and the upper back-up roll 8. In the machine, the work rolls 6, 7 and intermediate rolls 9 are connected to conventional vertical roll bending equipment 10, 1, respectively.
0' is installed. Further, the upper work roll 6 is disposed to be appropriately shifted to the downstream side in the rolling direction Z, and in order to adjust the horizontal deflection of the roll 6 due to the rolling load P, a presser roll 12 having approximately the same body length as the roll 6 is provided. is disposed on the shifted side, and a plurality of back-up rolls 13, 13a are disposed on the shifted side of the presser roll 12 in the roll axis direction to support the presser roll 12, and the moving device 14
It is configured to be movable in a straight line direction connecting the rotation centers of the upper work roll 6 and the presser roll 12. Therefore, in this rolling mill, the pressing force applied to the presser roll 12 is individually adjusted via the moving device 14 and the back-up rolls 13, 13a, and changes in the pressing force are used as vertical displacement, and the deflection of the upper work roll 6 is The shape of the rolled material 2 in the width direction can be freely adjusted at each part in the roll body length direction, and the shape of the rolled material 2 in the width direction can be controlled by using the roll bending devices 10, 10' for the upper and lower work rolls 8, 7.

However, in each of the above-mentioned rolling mills, as the rolling progresses, the work rolls that come into contact with the rolled material 2 are deflected by the rolling load P, causing large local surface pressures to occur at both ends of the plate, causing the roll surfaces to wear out. A so-called plate end mark 15 occurs. In addition, in the rolling mill shown in FIG. 2, on the surfaces of the upper and lower work rolls 3, 3' and the back-up rolls 4, 4', there is a problem that occurs at the portion corresponding to the long end of the intermediate roll 5, 5' body. Roll marks 16, 16a occur due to wear due to high local surface pressure. For this reason, there is a problem in that the roll marks 16 are transferred to the plate surface during rolling, resulting in a deterioration in the quality of the plate. This problem is particularly serious in cold rolling mills.

On the other hand, in the rolling mill shown in FIG. 3 and FIG. Roll marks 17 corresponding to the long ends of each back-up roll are formed on the roll surface in the same manner as in the case of the conventional intermediate rolls 5 and 5' shown in FIG.
This is transferred to the plate surface.

Therefore, in order to prevent the roll marks 16, 17 and the plate end marks 15, so-called Coffin schedule rolling is carried out in which the rolling order of the rolled material 2 is regulated from wide plates to narrow plates one after another. This method is one of the factors that impedes productivity improvement, and therefore, there is a strong demand for a rolling method that eliminates sheet edge marks and roll marks and allows so-called schedule-free rolling that does not require such rolling order regulation. .

The present invention aims to propose a rolling method that eliminates such conventional drawbacks, and in which the work rolls 3, 3' in contact with the rolled material 2 and the shape of the rolled material are used in a multi-high rolling mill of four or more high rolling mills. The rolls 5 and 5', which are configured to be movable in the axial direction of the rolls for control and the like, are driven to oscillate in the respective axial directions at a very low speed and with short strokes during rolling.

Hereinafter, one embodiment of the rolling method according to the present invention will be described in the fifth embodiment.
The six-high rolling mill shown in the figure will be described, and the same members as those in the conventional device will be given the same numbers and detailed explanations will be omitted.

Here, for convenience of explanation, the diameter D _W of the upper and lower work rolls 3, 3' is 400 mmφ, the diameter D _M of the intermediate rolls 5, 5' is 500 mmφ, the rolling speed V _R is 1000 m/min, and each roll 3, 3' and If the oscillating speed V _S in the axial direction of the rolls 5 and 5' is 10 mm/min, the oscillating stroke S is ±50 mm, and the oscillating time per reciprocating stroke 2 S is T _S , then the rotation of the upper and lower work rolls 3 and 3' The number N _W is approximately 800r.pm, the rotation speed N _M of intermediate rolls 5 and 5' is approximately 640r.pm, the oscillation rate time T _S per reciprocating stroke 12S is 100/10 = 10min, V _S /V _R = 10 ^-5 .

Now, the present applicant previously explained that when rolling a normal cold rolled steel plate using a test rolling mill (not shown),
Results of operation with the intermediate rolls 5, 5' set to move in the axial direction so that at least one end of the long body end of the intermediate rolls 5, 5' is located at an arbitrary position on the long body part of the work rolls 3, 3'. , roll marks due to the long ends of the intermediate rolls 5, 5' should not occur on the surfaces of the work rolls 3, ³ ' until the number of rolling times of each roll 3, 3' and 5, 5' reaches approximately 104 times. has been proven. Therefore, if we calculate the rolling time of each roll until the number of rolls reaches 10 ⁴ in the rolling mill shown in Fig. 5, the rolling time of work rolls 3 and 3' T _W ≒10 ⁴ /800≒ 12.5
min Rolling time of intermediate rolls 5, 5' T _M ≒10 ⁴ /640≒15.6mi
It becomes n. Therefore, the oscillation time T _S is 10min<
It will be 12.5-15.6min. That is, each roll 3,
Fine speed (V _S = 10 mm/min) and short stroke (S = ±50 mm) during rolling of 3' and 5,5' respectively.
When oscillating continuously or intermittently, the contact positions between the rolls 3, 3' and 5, 5' and between the work rolls 3, 3' and the rolled plate material 2 constantly change,
This means that the number of rolls at the same contact position can always be kept below ¹⁰⁴ times, and the upper and lower work rolls 3,
It is possible to prevent the occurrence of roll marks on the surfaces of the work rolls 3' and the back-up rolls 5, 5', as well as the occurrence of plate edge marks on the work roll surfaces. Further, it is desirable that the oscillation speed V _S be as low as possible in order to reduce the oscillation driving force.

As is clear from the above explanation, by using the rolling method of the present invention, it is possible to prevent the occurrence of plate edge marks and roll marks, and to perform schedule-free rolling, thereby improving the surface quality of the rolled material. And it greatly contributes to improving productivity.

Although the present invention has been described with respect to the 6-high rolling mill shown in FIG. 5, the present invention is not limited to this embodiment.
In the case shown in the figure, this can be applied to the work rolls 3 and 3', and in the rolling mill shown in FIG. 3, the work rolls 6 and 7 and the presser roll 12 can be used.

[Brief explanation of drawings]

1 and 2 are schematic front views of a 4-high and 6-high rolling mill equipped with a conventional roll shift function and roll bending device, respectively, and FIGS.
The figure shows a schematic side view and a front view of a conventional 5-high rolling mill equipped with a horizontal work roll bending device in addition to a vertical roll bending device, and Fig. 5 shows a 6-high rolling mill used in the method of the present invention. A schematic explanatory diagram of the machine is shown. 1 and 1' are roll bending devices, 2 is a plate material,
3 and 3' are work rolls, 4 and 4' are backup rolls, and 5 and 5' are intermediate rolls.

Claims (1)

[Claims] 1. In a multi-stage rolling mill comprising a work roll that is in contact with a rolled material and has a plurality of rolls of 4 or more stages, and a roll that can be moved and adjusted in the roll axis direction for controlling the shape of the rolled material, each of the rolls is A rolling method characterized in that the rollers are oscillated in each axial direction at a slow speed and with short strokes during rolling.