JPH05123709A - 14 stages rolling mill - Google Patents

Abstract

PURPOSE:To provide a 14 stages rolling mill with roll arrangement that the capacity to transmit torque is raised and also shape change is difficult to be generated even when rolling load is changed. CONSTITUTION:This rolling mill is provided with a pair of upper and lower work rolls 2 which are brought into contact with a rolled stock, a pair of right and left 1st intermediate rolls 3 with which those work rolls are supported, a 2nd intermediate roll 4 which is simultaneously brought into contact with a pair of those right and left 1st intermediate rolls, a back-up roll 6 in the middle with which the 2nd intermediate roll is supported and back-up rolls 5 on both right and left sides which are arranged on both right and left sides of the back-up roll in the middle and with which the 1st intermediate rolls are supported. The back-up roll in the middle is made into a divided roll, the back-up tolls on both right and left sides are made into solid rolls and roll arrangement that the ratios of the diameter D2 of the 1st intermediate roll to diameters D1, D4, D3, D5 of other rolls satisfy certain relations is taken.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-pressure 14-high rolling mill for rolling a hard thin plate material such as stainless steel or copper alloy.

[0002]

2. Description of the Related Art As a 14-high rolling mill, for example,
The one described in Japanese Patent No. 424 is publicly known. In this 14-high rolling mill, each of a pair of upper and lower work rolls contacting the rolled material is supported by two first intermediate rolls, and each of the first intermediate rolls contacts one second intermediate roll, The first
And each of the second intermediate rolls was supported by a backup roll. And the said 1st intermediate | middle roll was made into the drive roll. Further, the left and right backup rolls contacting the first intermediate roll are solid rolls, and the central backup roll contacting the second intermediate roll is a split roll (bearing roll), so that the crown can be adjusted. It had been.

[0003]

In the above-described conventional 14-high rolling mill, since the first intermediate roll having a relatively small diameter is rotationally driven, the torque transmission capability is low, and the rolling reduction ratio is high in a relatively thick plate region. There was a problem that I could not get it and had to increase the number of passes. Further, in the above-mentioned conventional one, since the backup rolls on both sides are solid, the roll is largely deflected, and the shape cannot be sufficiently controlled only by the division adjustment of the central backup roll.

That is, when the left and right backup rolls are solid rolls, the elastic load of the rolls due to the rolling load is too large, and the rolled plate shape becomes very bad. Therefore, if it is attempted to correct this deflection amount by the central backup roll (divided roll), the corrected deflection amount of the central backup roll becomes too large, and the divided roll (bearing roll) is overloaded with too much load. Had significantly shortened its life.

Further, in order to correct the bending of the rolls, it is conceivable to attach roll crowns to the backup rolls on both the left and right sides. However, if roll crowns are prepared for various rolling loads, the number of rolls increases and management Becomes difficult. Further, the roll replacement becomes complicated and the operability deteriorates. Therefore, in a 14-high rolling mill having solid rolls, there is a demand for a roll arrangement in which the shape is not significantly changed by the rolling load which changes depending on the rolling pass schedule (material, rolling reduction, etc.) of the plate.

Therefore, an object of the present invention is to provide a 14-high rolling mill having a roll arrangement in which the torque transmission capability is enhanced and the shape is unlikely to change even when the rolling load changes.

[0007]

In order to achieve the above object, the present invention takes the following means. That is, the feature of the present invention is that the pair of upper and lower work rolls contacting the rolled material, the pair of left and right first intermediate rolls supporting the work rolls, and the pair of left and right first intermediate rolls are simultaneously contacted. A second intermediate roll, a central backup roll that supports the second intermediate roll, and left and right backup rolls that are disposed on the left and right sides of the central backup roll and that support the first intermediate roll, In the 14-high rolling mill, the central backup roll is a split roll, the left and right backup rolls are solid rolls, and the left and right backup rolls are drive rolls. The diameter of D
₁ , the diameter of the first intermediate roll is D ₂ , the diameter of the second intermediate roll is D ₄ , the diameters of the backup rolls on the left and right sides are D ₃ , and the diameter of the central backup roll is D ₅ , The diameter of the roll is α = D ₁ / D ₂ , β
= D ₃ / D ₂ , γ = D ₄ / D ₂ , and δ = D ₅ / D ₂ ,

[0008]

[Equation 2]

And β <1 + 4 / (γ-
There is a point that 2) is satisfied. Furthermore, α> 0.5, 1.0
<Γ <3.0 and 1.0 <β.

[0010]

According to the present invention having the above-described structure, the left and right backup rolls are solid rolls, so that the rolls can be drive rolls. Since the backup roll has a larger diameter than the intermediate roll, by using this large-diameter backup roll as a drive roll, it is possible to transmit a large torque as compared with a conventional one that drives a small-diameter intermediate roll. it can.

On the other hand, if the backup rolls on both the left and right sides are solid rolls, the rolls are solid and therefore easily bent by the rolling load. Therefore, it is necessary to reduce the load applied to the solid rolls by adjusting the roll arrangement, and to receive the load on the central split rolls instead. That is, the bending can be reduced by increasing the load applied to the central backup backup roll and reducing the load applied to the left and right solid backup rolls.

Therefore, in the present invention, since η is minimized, the load acting on the left and right backup rolls is minimized, and the deflection of the backup rolls is minimized. Further, by setting the ranges of α, β and γ to the ranges of the present invention, mutual interference between the rolls can be prevented. The reason will be described in detail in the examples below.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. 2 and 3, the 14-high rolling mill of the present invention is
It has a pair of upper and lower work rolls 2 that come into contact with the rolled material 1. Each of the work rolls 2 is simultaneously supported by the two first intermediate rolls 3 arranged on the left and right sides of the work rolls 2 via the work rolls 2. The pair of left and right first intermediate rolls 3 are in contact with one second intermediate roll 4 arranged on a vertical line passing through the center of the work roll 2. Further, each of the pair of left and right first intermediate rolls 3 is supported by backup rolls 5 arranged on both left and right sides. Further, the second intermediate roll 4 is supported by a central backup roll 6 arranged on a vertical line passing through the center lines of the work roll 2 and the second intermediate roll 4.

The work roll 2 is a small diameter solid roll having a straight outer shape. This work roll 2
Is a non-driving roll. The first intermediate roll 3
Is a solid roll, but the outer peripheral surface 7 at one end
Are formed in a tapered or curved tapered shape. The first intermediate roll 3 can be moved in the axial direction by a driving means (not shown). This first
The intermediate roll 3 is also a non-driving roll.

The second intermediate roll 4 is also a solid roll,
Further, the outer peripheral surface 8 at one end thereof is formed in a taper or a curved taper shape different from that of the first intermediate roll 3. The second intermediate roll 4 is also movable in the axial direction by a driving means (not shown). This second intermediate roll 4 is also a non-driving roll. The backup rolls 5 on both the left and right sides are large-diameter solid rolls, and their outer peripheral surfaces are formed straight. The backup roll 5 is a drive roll, the roll end is rotatably supported by a bearing 9, and the bearing end is connected to a drive shaft 11 via a universal joint 10.

The central backup roll 6 is composed of axially divided bearings. Each of the split rolls (bearing rolls) is rotatably supported by a saddle 12. Each saddle 12 is independently movable in the vertical direction by a pushing means (not shown). In the 14-high rolling mill, when using solid rolls for the backup rolls 5 on both the left and right sides, the central split rolls
Deflection is larger than that of 6. However, by optimizing the load distribution between the backup roll 6 in the center and the backup rolls 5 on the left and right sides, the load acting on the backup rolls 5 on the left and right is reduced, its deflection is prevented, and the deflection change of the work roll 2 is prevented. (Rolling shape change) can be adjusted.

That is, if the roll arrangement of the present invention is adopted,
The load distribution on the left and right backup rolls can be optimized. The reason will be described below. The symbols are defined as follows based on FIG. D _1: Wa - Crawling second diameter D _2: the first intermediate rolls 3 having a diameter D _3: the diameter D of the left and right sides of the backup roll 5 _4: second intermediate rolls 4 of diameter D _5: diameter of the central backup roll 6 P _1: Wa - rolling load P ₂ acting on the crawl 2: work roll 2 and the rolling load P ₃ acting between the first intermediate rolls 3: first intermediate rolls 3 and the left and right sides of the backup roll
Rolling load P acting between 5 _4: first intermediate rolls 3 and the rolling load P ₅ acting between the second intermediate rolls 4: rolling load theta ₁ which acts between the second intermediate rolls 4 and the center of the backup roll 6: Acute angle formed between the action direction of rolling load P ₂ and the horizontal direction θ ₂ : An acute angle formed between the action direction of rolling load P ₃ and the horizontal direction θ ₃ : An acute angle formed between the action direction of rolling load P ₄ and the horizontal direction α = D ₁ / D ₂ β = D ₃ / D ₂ γ = D ₄ / D ₂ δ = D ₅ / D ₂ η = P ₃ / P _{1 According to} Fig. 1, balance the loads acting on the work roll 2 and the first intermediate roll 3. Think

First, the force balance of the first intermediate roll 3 will be considered. Power from the work rolls 2, x-direction: P ₂ cos θ ₁ y-direction: the force from P ₂ sin θ ₁ on both sides of the backup roll 5, x-direction :-P ₃ cos θ ₂ y directions :-P ₃ sin θ ₂ force from the second intermediate rolls 4, x direction: P ₄ cos _{θ 3} y-direction :-P ₄ sin theta ₃ first intermediate roll 3, since the force is _{balanced, P 2 cos θ 1 -P 3} cos θ ₂ + P ₄ cos θ ₃ = 0 ... P ₂ sin θ ₁ −P ₃ sin θ ₂ −P ₄ sin θ ₃ = 0.

Similarly, the following balance equation holds for the work roll 2. P ₁ -2P ₂ sin θ ₁ = 0 ... By multiplying the above formula by sin θ ₃ and multiplying the above formula by cos θ ₃ and adding both formulas, P ₂ sin (θ ₁ + θ ₃ ) −P ₃ sin ( θ ₂ + θ ₃ ) = 0 ∴P ₃ = P ₂ sin (θ ₁ + θ ₃ ) / sin (θ ₂ + θ ₃ ) ... From the above equation, P ₂ = 0.5 · P ₁ / sin θ ₁ This P ₂ Is substituted into the above equation, P ₃ = P ₁ · 0.5 · sin (θ ₁ + θ ₃ ) / {sin (θ ₂ + θ ₃ ) · sin (θ ₁ )} is obtained.

Therefore, η = P ₃ / P ₁ = 0.5 · sin (θ ₁ + θ ₃ ) / {sin (θ ₂ + θ ₃ ) · sin (θ ₁ )}. Since the rolling load P ₁ is constant, if θ ₁ , θ ₂ , and θ ₃ that minimize η in the above equation are selected appropriately, P ₃ will be the minimum and the right and left solid backup rolls 5 will be Deflection can be minimized.

In order to minimize η in the above equation, at least the denominator must be maximized. That is, it is necessary to maximize sin (θ ₂ + θ ₃ ). That is, sin
When (θ ₂ + θ ₃ ) = 1 and θ ₂ + θ ₃ = π / 2, at least η in the equation can take the minimum value. Therefore, η _min ≦ 0.5 · sin (θ ₁ + θ ₃ ) / sin θ ₁ ...

When the above equation is expanded, it becomes 0.5 sin (θ ₁ + θ ₃ ) / sin θ ₁ = 0.5 (sin θ ₁ cos θ ₃ + cos θ ₁ sin θ ₃ ) / sin θ ₁ . That is, η _min ≦ 0.5 (sin θ ₁ cos θ ₃ + cos θ ₁ sin θ ₃ ) / sin θ ₁ ...

In the above equation, the condition that η becomes small is that at least cos θ ₁ and cos θ ₃ take the minimum values. Therefore, the condition that cos θ ₁ and cos θ ₃ have the minimum value is obtained. First, the condition that the left and right first intermediate rolls 3, 3 do not contact each other is that (D ₁ + D ₂ ) cos θ ₁ > D ₂ (D ₂ + D ₄ ) cos θ ₃ > D ₂ from FIG. 4. That is, cos θ ₁ > D ₂ / (D ₁ + D ₂ ) cos θ ₃ > D ₂ / (D ₂ + D ₄ ). Therefore, the minimum value of cos θ ₁ and cos θ ₃ is cos θ ₁ = D ₂ / (D ₁ + D ₂ ) cos θ ₃ = D ₂ / (D ₂ + D ₄ ).

At this time, sin θ ₁ and sin θ ₃ can be expressed by the following equations.

[0025]

[Equation 3]

Then, substituting these values into the above equation gives the following equation.

[0027]

[Equation 4]

That is, η_minIs the expression on the right side of the above
It's time to make it small. Therefore, minimize the right side of the expression
Η can be minimized by selecting such α and γ.
At this time, it acts on the backup rolls 5 on both
Load is minimized. But the important thing here is
In the above equation, the angle θ₁, Θ₂, Θ₃Is any value
It is not allowed to take. That is, roll diameter
D₁, D₂, D ₃, D_Four, D_FiveAngle is limited by
Is Rukoto. That is, when selecting α and γ,
This means that there is a limit to the diameter of the ring.

Therefore, the limitation of the roll diameter will be considered.
Based on Fig. 5, the condition that the left and right backup rolls 5 and the second intermediate roll 4 do not interfere is as follows.

[0030]

[Equation 5]

When the point A in FIG. 5 is the origin (0,0), the following equation holds.

[0032]

[Equation 6]

Under the condition that the first intermediate rolls 3 do not come into contact with each other, the minimum value of cos θ ₃ becomes the above equation,
Substituting this equation into equation (10) gives the following equation.

[0034]

[Equation 7]

Therefore, by minimizing the right side of the above expression and satisfying the condition of the above expression (11) or (12), η
Can be minimized. Incidentally, it is general to adopt γ> 2 rather than γ <2. Furthermore, considering the limitations of the roll diameter, a second intermediate rolls 4, since it is intended to support the first intermediate rolls 3, the diameter D ₄ of the second intermediate rolls 4 of the first intermediate rolls 3 diameter D ₂ Should be greater than. Therefore, it is necessary that γ> 1.

When γ is 2 or more, the increase of γ determines the upper limit of β according to the equation (11). At this time, β is the diameter of the backup rolls 5 on both sides,
Larger diameter has less bending. Therefore, "1 <β <
Considering the limit to “5”, γ <3 from the above equation (11). That is, “1 <γ <3” becomes an appropriate value.

Next, let us consider what value α can take. Therefore, first, let us look at what range the minimum value of η is. Therefore, the diameter of each roll is determined as follows. D ₁ = 100mm, D ₂ = 40mm, D ₃ = 600mm, D ₄ = 80m
m, D ₅ = 100 mm At this time, α = 2.5, β = 15, γ = 2.0, and δ = 2.5.

Then, by fixing θ ₁ and θ ₃ and changing θ ₂ , the value of η in the above equation is changed to examine the shape change of the rolled material (the shape that changes per ton of rolling load). It was At this time, the left and right backup rolls 5
The case of using a solid roll and the case of using a split bearing roll were compared.

Similar considerations were made for the following roll diameters. D ₁ = 60 mm, D ₂ = 40 mm, D ₃ = 600 mm, D ₄ = 80 mm,
D ₅ = 100 mm (α = 1.5, β = 15, γ = 2.0, δ = 2.5) The results of the above consideration are shown in FIG. It can be seen from FIG. 6 that η
When <0.6, the shape change is small and the difference between the bearing roll and the solid roll is small.

Therefore, the minimum value of η is 0.6 or less. Therefore, when η _min ≦ 0.6, the following equation is derived from the above equation.

[0041]

[Equation 8]

From the above, at least "α>0.5"
Must be To summarize the above,

[0043]

[Equation 9]

By so doing, mutual interference between the rolls can be prevented, the load acting on the left and right backup rolls 5 can be reduced, and the flexure of the backup rolls 5 can be reduced. According to the embodiment of the present invention having the above-mentioned configuration, the backup rolls 5 on both the left and right sides are not split rolls but solid rolls, so the backup rolls 5 can be drive rolls.
Then, by rotating the drive shaft 11, the backup rolls 5 on both the left and right sides rotate, and this rotation is transmitted to the work roll 2 via the first intermediate roll 3 and the rolled material is rolled.
Roll one drive.

FIG. 7 is a graph showing the relationship between the diameter of the drive roll and the rated torque. In a general 14-high rolling mill, the diameter of the first intermediate roll is about 150 to 240 mm, and the diameter of the backup roll is about 300 to 500 mm, but if the backup roll is driven, it will not be restricted by the torque. Can be seen from this graph. That is, conventionally, all four first intermediate rolls were driven to transmit the required torque, but since the pair of upper and lower first intermediate rolls are close to each other, the diameter of the transmission portion is set to be equal to or smaller than the roll diameter. There was a need.
However, according to the embodiment described above, since the large diameter backup roll 5 is driven, a large torque can be transmitted.

The present invention is not limited to the above embodiment.

[0047]

According to the present invention, by rotating and driving a large diameter backup roll, the torque transmission limit is dramatically improved and the number of passes can be reduced. Moreover, the structure can be made simple and inexpensive by performing the rotational driving and the axial movement by different rolls.

Then, η is minimized, and α, β, γ
Since the load applied to the solid backup rolls on both the left and right sides is reduced by selecting the roll diameter so that the value of is in the appropriate range and arranging the rolls appropriately, Deflection is reduced and highly precise shape control is possible.

[Brief description of drawings]

FIG. 1 is an enlarged view of a roll arrangement of the present invention.

FIG. 2 is a roll layout diagram of the 14-high rolling mill according to the embodiment of the present invention.

3 is a cross-sectional view taken along the line AA of FIG.

FIG. 4 is an explanatory diagram of roll arrangement.

FIG. 5 is an explanatory diagram of roll arrangement.

FIG. 6 is a graph showing the relationship between η and shape change.

FIG. 7 is a graph showing the relationship between drive roll diameter and rated torque.

[Explanation of symbols]

 1 rolled material 2 work roll 3 first intermediate roll 4 second intermediate roll 5 backup rolls on both left and right sides 6 central backup roll

Claims (2)

[Claims] 1. A pair of upper and lower work rolls that come into contact with a rolled material, a pair of left and right first intermediate rolls that support the work rolls, and a second intermediate roll that simultaneously comes into contact with the pair of left and right first intermediate rolls. A central backup roll that supports the second intermediate roll, and left and right backup rolls that are disposed on both left and right sides of the central backup roll and support the first intermediate roll are provided. In the 14-high rolling mill, which is a split roll and the left and right backup rolls are solid rolls, the left and right backup rolls are drive rolls, and the diameter of the work roll is D ₁ . The diameter of the first intermediate roll is D ₂ , the diameter of the second intermediate roll is D ₄ , the diameters of the backup rolls on the left and right sides are D ₃ , and When the diameter of the roll is D ₅ , the diameter of each roll is α = D ₁ / D ₂ , β = D ₃ / D
₂ , γ = D ₄ / D ₂ and δ = D ₅ / D ₂ , And a β <1 + 4 / (γ−2) is satisfied, and a 14-high rolling mill is characterized. 2. The 14-high rolling mill according to claim 1, wherein α> 0.5, 1.0 <γ <3.0, 1.0 <β.