JPH0113925B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rolling mill having a function of preventing thinning of both ends of a rolled strip.

FIG. 1 is a front view of a conventional rolling mill, FIG. 2 is a side view of the same, and FIG. 3 is for explaining the action of the working rolls of the rolling mill shown in FIGS. 1 and 2.

As shown in FIGS. 1 and 2, a steel rolling mill generally includes a pair of parallel, spaced apart gate-shaped frames 5, 5', which are connected in a parallel spaced relationship. Between the frames 5 and 5', an upper working roll 1 and a lower working roll 2 each driven by power are arranged in a vertically stacked state, and an upper back that rotates in contact with these is arranged. The up roll 3 and the lower back up roll 4 are arranged vertically in parallel, respectively,
As is well known, the rolls are supported by bearings 10 held by frames 5, 5', and are configured to compress the rolls by means of rolling down devices 6, 6'.

When rolling a plate using a rolling mill, as shown in FIG. 3, working rolls 1 and 2 are rotated by an electric motor 7, and a strip 8 is passed between the rolls 1 and 2 and rolled. At this time, the working rolls 1 and 2 tend to bend due to the rolling reaction force, so the structure is such that this is reinforced by the back-up rolls 3 and 4.

However, in the above case, working role 1,
2 receives a horizontal force due to the reaction force caused by the rotational power, but if the moment due to the rolling reaction force is ignored, this force becomes as follows. That is, if the rotation torque is τ and the diameter of the working rolls 1 and 2 is 2R, this reaction force (horizontal force F) is F=
It becomes τ/R. Further, when a horizontal force F is applied to the working rolls 1 and 2, the rolls 1 and 2 are deflected in the horizontal direction, and the central portions of the rolls are evacuated horizontally. As a result, both ends of the strip 8 tend to be strongly rolled, as shown in FIG. 3D. Therefore, the rolled plate had the disadvantage that the end portion 9 became thinner.

Working rolls 1 and 2 are rotated by the 8th roll due to reaction force.
It transforms as shown in the figure. That is, the portion that contacts the strip 8 is flat, and the far end portion is circular. Therefore, both ends 9 of the strip 8 are rolled more strongly than the center due to this effect, and have the disadvantage that they are thinner than the center.

The present invention was proposed in order to solve the above-mentioned conventional drawbacks, and includes a rolling roll, a hollow roll cell having a cylindrical inner wall and rotated by an electric motor, and a hollow roll cell having inner circumferences at both ends of the roll cell within the roll cell. A non-rotating central shaft supported by a pair of bearings and inserted in a coaxial relationship, and a pair of pistons disposed at opposite positions that are provided between the pair of coaxial bearings and actuated by fluid pressure. By pressing the piston against the inner wall of the roll cell using fluid pressure, the roll cell is prevented from deflecting and vibrations are damped. They are held in a bearing box and have a cylindrical inner wall, and each is rotated by an electric motor.The center shaft is held in the roll cell with a certain gap along the inner wall of the roll cell, and one end is attached to the bearing box by a bracket. It is fixed and stationary, and the central shaft is provided with a longitudinal groove parallel to the direction of entry of the strip, an outwardly opening piston is attached to this groove, and a fluid passage is provided in the central shaft. It is an object of the present invention to provide a rolling mill in which a pressurized fluid passes through this passage to actuate a piston and press the piston against the inner wall of the roll cell, thereby preventing horizontal deflection of the working roll.

Embodiments of the present invention will be described below with reference to the drawings.The configuration of the rolling mill in the present invention is the same as that of the conventional one, but the upper and lower working rolls are used as lateral deflection control rolls, and when rolling a strip, the rolling mill is This prevents roll deflection due to force and damps roll vibration. Therefore, only the lateral deflection control roll will be explained here, and other details will be omitted.
Furthermore, since the upper and lower lateral deflection control rolls have the same structure, this structural description will be made only for the upper lateral deflection control roll.

Fig. 4 is a front view of a lateral deflection control roll showing an embodiment of the present invention, and Fig. 5 is a longitudinal section of the lateral deflection control roll along a plane passing through the center of the roll and parallel to the rolling direction of the strip (horizontal plane in the illustrated example). Sectional view, FIG. 6 is a cross-sectional view.

In FIGS. 4 and 5, the fastener 15 is fixed to the central shaft 12 of the lateral deflection control roll 11. In FIGS. A bracket 14 is attached to the bearing box 13 that holds the roll body, and the end of the stopper 15 is connected to the bolt 1 screwed into the bracket 14 from above and below.
6, the central shaft 12 is fixed and stationary.

Next, in FIGS. 5 and 6, the lateral deflection control roll 11 has an elongated hollow roll cell 1 in the center.
7. A drive shaft 18 fixed to the drive side and rotatable by an electric motor, a roll body consisting of a journal 19 fixed to the operation side, a central shaft 12 inserted into the roll cell 17 and held stationary, etc. It consists of the main parts.

In addition, the roll body has a bearing box 1 at both ends.
Bearings 20, 2 fitted into 3, 13'
As usual, it is supported by 0'.
The roll cell 17 has a cylindrical inner wall spaced apart in the radial direction from the outside of the stationary central shaft 12, and the central shaft 12 is held by bearings 21, 21' fitted into both ends of this inner wall. Further, an oil stopper 22 is attached to the end of the journal 19.

Further, in the central axis 12, rectangular grooves 23 and 23' that are directly facing each other and open outward extend in the longitudinal direction, respectively.
Piston 2 is closed at both ends to create a pressure chamber.
4 and 24' are suitably enclosed in these pressure chambers, respectively. In addition, a fluid passage 2 is provided within the central shaft 12.
5, 25' and 26 each extend in the axial direction;
The fluid passages 25 and 25' open into the pressure chamber through fluid passages 27 and 27', which are perpendicular to the axis, respectively, and the fluid passage 26 is connected to the inner wall of the roll cell 17 and the outer periphery of the central axis 12 by a fluid passage 28 which is perpendicular to the axis. It opens into an annular space 29 formed by a surface.

The pistons 24, 24' are rod-shaped bodies with an umbrella-shaped cross section, and grooves 30, 30' are provided in the longitudinal direction on the umbrella-shaped surfaces in contact with the inner wall of the roll cell 17, and these grooves 30, 30' Small holes 31 and 31' communicating with the rectangular grooves 23 and 23' of the central shaft 12 are provided, respectively.

Next, to explain the operation, the pressure oil supplied to the fluid passages 25 and 25' of the central shaft 12 by a pressure oil pump (not shown) provided outside the machine passes through the passages 27 and 27'. Entering the pressure chamber, the pistons 24, 24' are actuated outwardly, pressing them against the inner wall of the roll cell 17. When horizontal deflection of the roll is to be prevented, the hydraulic pressures supplied to the passages 25 and 25' are differentiated. The horizontal deflection of the roll body can be controlled by this difference in hydraulic pressure.

Also, some of the pressure oil is in the small hole 3 provided in the piston.
1, 31' to lubricate the contact between the inner wall of the roll cell and the outer surface of the piston, and is recovered from the annular space through fluid passages 28, 26. The roll vibrations are then damped by simultaneously actuating both pistons 24, 24'.

Next, FIG. 7 is a cross-sectional view of a lateral deflection control roll in another embodiment, showing only the parts that are different from the first embodiment. That is, in FIG. 7, the pistons are rectangular pistons 35, 35' and are sealed in grooves so that the pressure shoes 37, 37' can swing through swing pins 36, 36', respectively.
In addition, the contact surfaces of the pressure shoes 37, 37' that come into contact with the inner wall of the roll cell 17 are shaped like an arc smaller than the radius of the inner wall of the roll cell 17.

Here, when the roll cell 17 rotates in FIG. 7, the oil in the annular space 29 flows on the inner circumferential surface of the roll cell 17 due to centrifugal force and adhesive force and rotates together with the roll cell 17.
An oil film is formed by passing through the wedge-shaped gap formed between the top surface of the roll cell 7' and the inner peripheral surface of the roll cell 17, and the roll cell is pushed up through this oil film.

Note that although Figures 4 to 6 show examples in which the piston is placed in the direction in which the strip material enters (generally horizontal direction), other effects can be achieved by placing the piston in the rolling direction (generally vertical direction). can get. Regarding the structure in this case, only the direction of the piston is in the rolling direction, and other details are as shown in Figures 4 to 6.
It is the same as the explanation of the figure.

Now, as shown in Figure 8, working roll 1,
2 is deformed by the rolling reaction force, that is, the part that contacts the strip is deformed flat as shown in the cross section B to B, and the end part is not pressurized, so it is not deformed as shown in the cross section A to A. It is circular. Therefore, both ends of the strip 8 tend to become thinner as shown in the figure due to this influence, and the strip tends to be mid-height.

FIG. 9 shows an example in which the working roll of the present invention is installed, in which pistons 24 and 24' are installed at right angles to the traveling direction of the strip material, and by supplying hydraulic pressure to these pistons, the degree to which the roll cell 17 is deformed into a flattened state can be controlled. It is made to be adjustable. In addition, when used in conjunction with the working roll bending P shown in FIG. 8, it is possible to adjust the tendency for both ends of the strip 8 to become thinner and the tendency for the strip to be thicker, and to roll the strip to a uniform thickness. be.

As explained in detail above, the present invention supports both ends of the inner periphery of the roll cell in a hollow roll cell with a pair of bearings, and a non-rotating central shaft inserted in a coaxial relationship, and the pair of coaxial shafts. By installing a pair of pistons located opposite each other between the bearings and operated by fluid pressure, it is possible to prevent the rolling roll from deflecting due to horizontal force, so that the strip can be rolled uniformly. . Moreover, by providing pistons on both sides parallel to the rolling direction and switching the oil pressure, forward and reverse rolling can be performed. Furthermore, by providing pistons on both sides, vibrations of the rolling rolls can be damped.

[Brief explanation of drawings]

Figure 1 is a front view of a conventional rolling mill, Figure 2 is a side view of the same, Figure 3 A is a perspective view of the roll arrangement in Figures 1 and 2, and Figure 3 B is a rolling state using the same working rolls. FIG. 3C is a side view illustrating the deflection state of the working roll.
Fig. 2 is a side view of the obtained strip, Fig. 4 is a front view of a lateral deflection control roll in a rolling mill showing an embodiment of the present invention, Fig. 5 is a sectional view taken from XX in Fig. 4, and Fig. 6
The figure is a sectional view from Y to Y in FIG. 5, FIG. 7 is a front sectional view of a lateral deflection control roll different from that in FIG. 6, and FIG. FIG. 8B is a sectional view from A to A in FIG. 8A, FIG. 8C is a sectional view from B to B in FIG. be. Explanation of the main parts of the figure, 11... Lateral deflection control roll, 12... Central shaft, 13, 13'... Bearing box,
17... Roll cell, 24, 24'... Piston,
25, 25', 26, 27, 27'...Fluid passage.

Claims (1)

[Claims] 1. A rolling roll is divided into a hollow roll cell having a cylindrical inner wall and rotated by an electric motor, and a pair of bearings supporting both ends of the inner periphery of the roll cell, and a non-rotating roller inserted in a coaxial relationship. The roll cell comprises a central shaft and a pair of pistons arranged at opposite positions that are provided between the pair of bearings of the same central shaft and are actuated by fluid pressure, and by pressing the pistons against the inner wall of the roll cell by fluid pressure. , a rolling mill characterized by preventing deflection of roll cells and damping vibrations.