JP2001259716A - Structure for holding hydraulic press and shock- absorber used for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a holding structure with which the propagation of vibration to a hydraulic press is effectively prevented even when the vibration is generated on the housing of a rolling mill in the direction crossing the axial line of the hydraulic press. SOLUTION: Shock-absorbers 8 are arranged between the side faces of the cylinder 3 of the hydraulic cylinder 2 which is incorporated in the housing 1 of a universal rolling mill and the housing 1 and the spring constant K of these shock-absorbers 8 is taken as K>=5.ωn2.W/g among the natural frequency ωn of the housing 1, the weight W of the hydraulic cylinder 2 and the gravitational acceleration g.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a holding structure for a hydraulic rolling device of a rolling mill, particularly a universal rolling mill, and a cushioning material used for the structure.

[0002]

2. Description of the Related Art As a universal rolling mill used for rolling an H-section steel, for example, there is a universal rolling mill shown in FIG. This comprises a pair of upper and lower horizontal rolls 21 and a pair of left and right vertical rolls 22 in the same plane,
The web WE of the rolled material WO is a pair of horizontal rolls 21, and
The H-shaped steel is rolled by rolling down the flange FR of the rolled material WO by the pair of vertical rolls 22 and the side portions of the horizontal rolls at the same time. By the way, the pair of rolling rolls 21 and 22 of such a universal rolling mill are
Conventionally, the position adjustment is generally performed by an electric jack, but in recent years, it has been increasingly performed based on the hydraulic AGC function under the demand of high dimensional accuracy for the H-section steel. Here, the hydraulic AGC function refers to a function for adjusting a rolling position during rolling according to a deviation between an actual rolling load and a target rolling load or a deviation between an actual thickness and a target thickness to obtain a predetermined thickness, It has been used for a long time in the field of sheet rolling. In this case, the AGC cylinder device is
It is generally carried out by housing the cylinder in the upper or lower part of the housing or by guiding the cylinder with a housing post, and is installed in a universal rolling mill in the same manner.

FIG. 3 shows a mounting side of a horizontal roll AGC cylinder 23 in a universal rolling mill.
The reference numeral 24 is provided with a certain gap laterally with respect to the housing 25 of the rolling mill in consideration of the workability of replacing the AGC cylinder 23. In the drawing, reference numeral 26 denotes a piston that applies a rolling force to the horizontal roll, and reference numerals 27 and 28 denote guide rings that are disposed between the cylinder 24, the piston 26, and the piston rod and also serve as seal packing.

[0004]

The AGC cylinder 23 is
When the H-section steel is rolled by the universal rolling mill installed as described above, as described above, the web WE and the flange FR of the rolled material WO are simultaneously engaged in the respective roll pairs and rolled. Therefore, when the rolled material WO bites, a shocking load acts in both the vertical direction and the horizontal direction. On the other hand, when the rolled material WO comes out, the load is rapidly removed. Accordingly, the housing 25 of the rolling mill vibrates vertically and horizontally.

That is, in any of these cases, vibrations in the Z direction and the X direction are generated in the housing 25 of the rolling mill as shown in FIG. Of these vibrations, Z
The vibration in the direction is the same as the operation direction of the piston 26 in the AGC cylinder 23 for the horizontal roll, so that there is no particular problem as in the vibration of the plate rolling mill. However, the vibration in the X direction is
Since a vibration load is applied to the cylinder 23 in a direction perpendicular to the axis thereof, there is a high possibility of causing pressure loss and other damage to the guide rings 27 and 28 and the like. Further, regarding the AGC cylinder 29 for the vertical roll, while the vibration in the X direction does not cause any particular problem, the vibration in the Z direction becomes vibration perpendicular to the axis, and there is a high possibility of damaging the guide ring and the like. There was a problem.

SUMMARY OF THE INVENTION An object of the present invention is to solve such problems of the prior art, and it is an object of the present invention to roll an H-section steel or the like and install a liquid in a housing of a rolling mill. Even if vibration of a pressure reduction device, for example, a hydraulic cylinder, in a direction intersecting with the axis line occurs, the transmission of the vibration to the hydraulic cylinder can be effectively suppressed to prevent early damage to the guide ring and the like. An object of the present invention is to provide a holding structure for a hydraulic pressure reducing device and a cushioning material used therefor.

[0007]

SUMMARY OF THE INVENTION A holding structure of a hydraulic pressure reducing device according to the present invention is, for example, a hydraulic pressure reducing device which can be a hydraulic cylinder incorporated in a housing of a universal rolling mill. And the spring constant K of the cushioning material is determined by the natural frequency ωn in the direction in which the cushioning material is arranged in the housing, in other words, in the direction orthogonal to the cylinder axis, and the hydraulic pressure reduction device. K ≧ 5 · ωn ² · W / g in relation to the weight W and the gravitational acceleration g. By the way, in this case, it is possible to dispose the cushioning material over the entire circumference of the cylinder side surface. However, as described with reference to FIG. 4, in consideration of the vibration transmitted from the rolling mill housing to the hydraulic pressure reduction device, Particularly damaging is the vibration directed in the axial direction of the rolling roll to which it is lowered, so that the cushioning material is preferably disposed on the side of the cylinder in the axial direction of the rolling roll.

[0008] According to such a holding structure, the cushioning member, which is arranged between the side surface of the cylinder of the hydraulic pressure reduction device and the housing of the rolling mill and whose rigidity is appropriately selected, is particularly suitable for the vibration of the housing. It functions to effectively suppress the transmission of vibration in the direction perpendicular to the cylinder axis to the hydraulic pressure reduction device,
This is why the rolling mill bites between the rolls and
Even if the housing vibrates due to its escape, the vibration load applied to the hydraulic pressure reduction device in the direction intersecting with the cylinder axis is greatly reduced, and the damage to the guide ring of the hydraulic pressure reduction device is sufficiently prevented. be able to. Here, the reason why the spring constant K of the cushioning material is K ≧ 5 · ωn ² · W / g is to reduce the relative vibration amplitude between the housing and the hydraulic pressure reduction device. This is because the input of the vibration load to the hydraulic pressure reduction device can be reduced to １ ／ or less, and the guide ring and the like can be sufficiently protected from early damage.

On the other hand, when the spring constant of the cushioning material is set to a value smaller than the above, an increase in the vibration load input to the hydraulic pressure reduction device cannot be denied, and the strength of the guide ring and the like must be increased. Premature damage will be forced. Further, the cushioning material of the present invention is provided between the side of the hydraulic pressure reduction device incorporated in the housing of the rolling mill and the housing.
In relation to the natural frequency ωn in the direction in which the cushioning member is disposed, the weight W of the hydraulic pressure reduction device, and the gravitational acceleration g, K ≧ 5 · ωn ² · W / g is satisfied. Thus, the above-described effects can be achieved.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view similar to FIG. 3 showing an embodiment of the present invention for one hydraulic pressure reduction device, here a hydraulic cylinder, and the overall configuration of the rolling mill itself is a universal rolling mill shown in FIG. Similar to that of the machine. Here, it is assumed that the hydraulic cylinder 2 is housed and arranged at the lower portion of the housing 1 of the rolling mill, and the cylinder 3 and the piston 4 are slidably contacted with each other via a guide ring 5 also serving as a seal packing, and the piston rod 6 is moved. Is also brought into sliding contact with a similar guide ring 7.

In this case, at least at a position corresponding to the axial direction of the horizontal roll, a cushioning material 8 is arranged between each side surface of the cylinder 3 and the housing 1 at an interval in the axial direction of the cylinder 3. Then, the total spring constant K of the cushioning material 9 on each side is, for example, 1.961330 MN.
/ Mm. In addition, such a buffer material 8 can be made of, for example, polyethylene terephthalate resin, polyester resin, or the like.

Although not shown, other pressing hydraulic cylinders of the pair of horizontal rolls are also arranged via the same cushioning material, and the respective pressing hydraulic cylinders of the vertical rolls of the pair are also arranged. Also, the spring constant K is set to a natural frequency ωn of the housing in the direction in which the cushioning material is disposed, the weight W of the hydraulic cylinder, and the gravitational acceleration g are K ≧ 5 · ωn ² · W / g. And housed in the housing.

According to the hydraulic cylinder holding structure thus constructed, in the prior art, the relative vibration amplitude of 0.5 mm and 35 Hz generated between the rolling mill housing and the hydraulic silling is set to 0.05 mm or less. be able to. Accordingly, here, the transmission of the axial vibration of the rolling roll, which is lowered by each hydraulic cylinder, to the hydraulic cylinder is effectively suppressed under the action of the cushioning material, so that damage to the guide ring and the like of the hydraulic cylinder is reduced for a long time. Can be effectively prevented.

[0014]

As described above, according to the present invention, it is possible to effectively reduce the vibration of the hydraulic pressure reduction device of the rolling mill in the direction intersecting with the axis, and to sufficiently prevent the guide ring and the like of the hydraulic pressure reduction device from being damaged. As a result, the maintenance cost of the rolling mill can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing an embodiment of the present invention.

FIG. 2 is a partial sectional front view and a side view of a universal rolling mill.

FIG. 3 is an enlarged sectional view showing a mounting side of an AGC cylinder of the universal rolling mill.

FIG. 4 is an explanatory view showing the action of an impact load on a rolling mill housing.

[Explanation of symbols]

 Reference Signs List 1 housing 2 hydraulic cylinder 3 cylinder 4 piston 5, 7 guide ring 6 piston rod 8 cushioning material

Claims (3)

[Claims] 1. A cushioning material is disposed between a side surface of a cylinder of a hydraulic pressure reduction device incorporated in a housing of a rolling mill and a housing, and a spring constant K of the cushioning material is determined by distributing the cushioning material of the housing. A holding structure for a hydraulic pressure reduction device that satisfies K ≧ 5 · ωn ² · W / g in relation to the natural frequency ωn in the setting direction, the weight W of the hydraulic pressure reduction device, and the gravitational acceleration g. 2. The holding structure for a hydraulic rolling device according to claim 1, wherein the buffer material is disposed in the axial direction of a rolling roll that is lowered by the hydraulic rolling device. 3. A cushioning member disposed between a side portion of a hydraulic pressure reduction device incorporated in a housing of a rolling mill and a housing, and a spring constant K of the housing in a direction in which the cushioning member is disposed. A buffer material that satisfies K ≧ 5 · ωn ² · W / g in relation to the natural frequency ωn, the weight W of the hydraulic pressure reduction device, and the gravitational acceleration g.