JPH0526562B2 - - Google Patents

Description

[Detailed description of the invention]

(a) Industrial Application Field The present invention relates to an eight-layer rolling mill for improving the shape and cross-sectional profile of rolled material. (b) Prior art In order to improve the shape (e.g., medium elongation, ear wave, quarterbuckle, etc.) and cross-sectional profile (e.g., plate crown, edge drop, etc.) of rolled materials such as steel strips, various rolls have been used. and rolling mills have been proposed. Representative examples of these will be briefly explained. A four-layer rolling mill in which the back-up rolls are moved in the axial direction is disclosed in Japanese Patent Application Laid-Open No. 49-29263. However, the equipment structure of this rolling mill is complicated and large-scale, and it lacks practicality. Therefore, in order to compensate for this drawback, the same applicant disclosed an improved rolling mill in Japanese Patent Publication No. 50-19510. This rolling mill inserts an intermediate roll between a work roll and a backup roll, and moves this in the axial direction. This method is highly practical and is actually widely used under the name HC mill. Furthermore, the present applicant has developed a device that moves the sleeve of the back-up roll of a quadruple rolling mill in the axial direction (Japanese Patent Application Laid-Open No. 103058/1982), or the crown of the work roll or back-up roll is variable using a pressure medium. (Special Publication No. 55-125). Other technologies used include variable speed rolling mills, roll benders, work rolls, and shifts. However, with the recent demand for diversification of product types, it has been recognized that the various techniques described above have limitations, particularly in shape and edge drop control.
Therefore, technologies incorporating conventional roll benders and work roll shifts were developed. For example, if a roll bender is incorporated into the above-mentioned new type rolling mill, shape control performance is considerably improved, but edge drop control performance is still insufficient. On the other hand, if the work roll shift is incorporated, the edge drop control performance is significantly improved, but the following new problems occur, and satisfactory results cannot be obtained. That is, in the case of thin plate hot rolling, there are the following problems. B. Lack of control stability due to localized wear at the end of the roll. (b) If you try to shift the roll during rolling,
The shift drive equipment requires a large amount of power, making the equipment expensive. Due to concerns about rolling problems, low speed rolling is forced, resulting in a drop in efficiency. This occurs in any rolling process. In the case of thin plate cold rolling, there are the following problems. B Shape defects and meandering occur in the stands following the applicable stand. (b) The tapered corner of the roll end transfers marks to the rolled material. C. During rolling, rolling troubles occur due to tension fluctuations during shifting. Next, in a six-layer rolling mill, the intermediate roll and back-up roll are rolled in the same direction at the same time (but
A possible method is to move the upper roll group and the lower roll group in opposite directions. but,
As mentioned above, the equipment structure becomes complicated and large-scale, and it lacks practicality. (c) Problems to be Solved by the Invention The problems to be solved by the present invention are to significantly improve shape and edge drop control performance, which have been insufficient in the past, at low equipment costs. (d) Means for Solving the Problems The eight-layer rolling mill of the present invention includes a pair of work rolls that contact the rolled material, and a pair of work rolls that contact the work rolls and are movable in the axial direction. It consists of a first intermediate roll, a pair of second intermediate rolls that are in contact with the first intermediate roll and have a body length shorter than the width of the rolled material, and a back-up roll that is in contact with the second intermediate roll. , a roll bender is provided between adjacent rolls of the rolls, and a diameter reduction process is performed on the end of at least one of the first and second intermediate rolls. Therefore, the above problems can be solved. (e) Example An eight-layer rolling mill of the present invention will be described with reference to the drawings. First, the eight-layer rolling mill shown in FIG.
It consists of a pair of first intermediate rolls 3, a pair of second intermediate rolls 4 that are in contact with the first intermediate rolls 3 and can be moved in the axial direction, and a backup roll 5 that is in contact with the second intermediate rolls 4. . A conventional roll belt 6 may be provided between adjacent rolls among the rolls 2, 3, 4, and 5. The shaft ends of the first intermediate roll 3, the second intermediate roll 4, or both may be subjected to a diameter reduction process as shown in FIG. For example, a linear taper A, a curved radius B, or a combination C of a straight line and a curved line may be used. The shafts at both ends of each roll are supported by roll jocks (not shown), and each roll jolt is supported within a roll housing. intermediate roll 3,
The intermediate rolls 3, 4 are moved in the axial direction by pushing out the shafts at both ends of the intermediate rolls 4 using a conventional feeding mechanism (for example, a screw mechanism, a hydraulic cylinder, a torque mechanism, etc.). On the other hand, by providing a similar jacking mechanism between the roll housing and the roll chock, it can also function as a roll bender. The eight-layer rolling mill shown in FIG. 2 is almost the same as the one shown in FIG. 1, but the second intermediate roll 4a is slightly different from the second intermediate roll 4 in FIG. The second intermediate roll 4a does not move in the axial direction, and its body length is made shorter than the width of the rolled material 1. (f) Effect In the eight-layer rolling mill shown in Fig. 1, the intermediate rolls 3 and 4 are sequentially shifted toward the center in the width direction of the rolled material 1, so the figures are exaggerated and indicated by the two-dot chain lines. As shown, the edges of the rolled material 1 tend to edge up. In addition to this roll shift, the edge-up effect can be controlled more precisely by appropriately combining roll bending or roll end diameter reduction processing. In the eight-layer rolling mill shown in FIG. 2, the edge-up effect is promoted by the second intermediate roll 4a having a short body length. In the present invention, the first intermediate roll and the backup
A pair of second intermediate rolls are provided between the rolls and are in contact with the first intermediate rolls and have a body length shorter than the width of the rolled material.
Since the intermediate roll is provided, by adjusting the rolling force when pressing the second intermediate roll with the back-up roll, not only edge drop control but also control of the center part of the strip width according to the roll profile on the entrance and exit sides of the rolling machine can be performed. Shape control is also possible, making even more excellent shape control possible. In other words, it is possible to control the shape from no edge drop to edge drop. <Specific Example 1> In a conventional cold rolling mill row consisting of five stands, the eight-layer rolling mill of the present invention was applied to the first and second stands. In addition, in this case, the second intermediate roll 4a
has a fixed short body. Entry side rolled material dimensions: Thickness 60 mm x width 150 mm x length 50 m Output side rolled material dimensions: Thickness 3 mm x width 1500 mm x coil The rolling reduction was 95% and the rolling speed was 1200 m/min. The rolling results are shown in Table 1.

【table】

[Table] (g) Effects According to the 8-layer rolling mill of the present invention, the edge drop of the rolled material can be reduced to about 1/10 or less, and the shape can also be reduced to 3-3.
It can be improved by as much as 4 times.

[Brief explanation of drawings]

FIG. 1 is a schematic front view of an 8-layer rolling mill. FIG. 2 is a schematic front view of the 8-layer rolling mill of the present invention. FIG. 3 is an explanatory view of the end of the roll used in the rolling mill of the present invention. FIG. 4 is an explanatory diagram showing an embodiment in which the rolling mill of the present invention is applied to a continuous rolling mill row. 1: Rolled material, 2: Work roll, 3: First intermediate roll, 4, 4a: Second intermediate roll, 5: Backup roll, 6: Roll bender.

Claims (1)

[Claims] 1 A pair of work rolls in contact with the rolled material, a pair of first intermediate rolls in contact with the work rolls and movable in the axial direction, and a plate width of the rolled material in contact with the first intermediate rolls. a pair of second intermediate rolls having a body length shorter than , and a backup roll in contact with the second intermediate rolls,
Eight-layer rolling, characterized in that a roll bender is provided between adjacent rolls among the rolls, and a diameter reduction process is performed on the end of at least one of the first and second intermediate rolls. Machine.