CN215467035U - Rolling mill with unequal-diameter working rolls - Google Patents

Abstract

A rolling mill with unequal-diameter working rolls is used for rolling metal strip foils and comprises an upper working roll and a lower working roll, wherein the roll diameter of the upper working roll is larger than or smaller than that of the lower working roll, and the linear speeds of the roll surfaces of the upper working roll and the lower working roll are the same during rolling. The utility model adopts the working rolls with different diameters to roll the band foil, which is not only beneficial to thinning the band foil, but also beneficial to obtaining better plate shape, and realizes the wide-width high-precision rolling of the band foil. The utility model breaks through the cognition of technicians in the industry on the working roller of the rolling mill, breaks through the technical bottleneck and provides a new technical solution for rolling the wide high-precision strip foil.

Description

Rolling mill with unequal-diameter working rolls

Technical Field

The utility model relates to the technical field of rolling mills, in particular to a rolling mill with unequal-diameter working rolls.

Background

At present, the upper and lower working rolls of a strip mill are designed with equal diameters both at home and abroad. As shown in fig. 1, a pair of upper and lower working rolls roll a metal strip or foil (hereinafter referred to as a strip foil), and a center layer 4 of deformation of a rolled material is located at the center of a roll gap to realize uniform deformation of a cross section of the material, from a two-roll mill to a twenty-roll mill. Such a design facilitates maintenance and exchange of the work rolls, and the drive structure thereof is thus simplified for the rolling mill.

The size of the work roll diameter is influential to the rolling of the strip. It is known that the smaller the diameter of the working roll, the more advantageous the thinning of the band foil 3, but this also presents problems: as shown in fig. 1, the small diameter work roll 1 has a small diameter, a small rigidity, a large biting angle to the strip foil 3, and a large lateral component force of the rolling force, and therefore has a large lateral bending tendency. In addition, the length of the biting arc of the small-diameter working roll 1 to the band foil 3 is not favorable for the uniform introduction of a lubricating medium into a roll gap, so that the thickness of an oil film in a rolling arc area is not uniform. These factors result in a large fluctuation of the arc length of the rolling arc surface in the width direction of the strip foil, eventually causing a defect in the rolled sheet shape. Under the same conditions, the right large diameter work roll 2 has a large diameter and a large rigidity, has a small biting angle with respect to the strip foil 3, and has a small lateral component force of the rolling force, and therefore has a small tendency to bend laterally. In addition, the bite arc length of the large-diameter working roll 2 to the band foil 3 is longer, so that a lubricating medium can be uniformly brought into a roll gap, and the thickness of an oil film in a calendering arc area is more uniform. These factors are all beneficial to reducing the arc length fluctuation of the rolling arc surface along the width direction of the strip foil, thereby obtaining better rolling shape. In conclusion, the small-diameter working roll is beneficial to rolling and is limited in that the rolled plate shape is difficult to control, so that the rolled width is not suitable to be too large; the large-diameter working roll is beneficial to controlling the rolled plate shape, is suitable for rolling width, but is not suitable for rolling thin. For wide-width strip foil with thickness less than 0.3mm, the diameter of the working roll must be small enough (usually 25-50mm in diameter) to obtain a large reduction amount, and the shape of the strip at this time is very difficult to control, which is also the bottleneck restricting the rolling of high-precision wide-width strip foil.

With the increasing urgent need of the market for high-precision wide-width strip foils, a new technical solution is urgently needed to break the barrier of the technical bottleneck and enable the strip foils to be rolled in a wide-width high-precision manner.

SUMMERY OF THE UTILITY MODEL

In order to overcome the defects in the background technology, the utility model discloses a rolling mill with unequal-diameter working rolls, which adopts the following technical scheme:

a rolling mill with unequal-diameter working rolls is used for rolling metal strip foils and comprises an upper working roll and a lower working roll, and is characterized in that: the roll diameter of the upper working roll is larger than or smaller than that of the lower working roll, and the linear speeds of the roll surfaces of the upper working roll and the lower working roll are the same during rolling.

The technical scheme is further improved, wherein the roller diameter of one of the upper working roller and the lower working roller is 1.5-5 times that of the other working roller.

The technical scheme is further improved, and the diameter of the upper working roll is smaller than that of the lower working roll.

Further improves the technical proposal that the roller diameter of the upper working roller is 25-100 mm.

Further improves the technical proposal that the effective roller surface width of the upper working roller is 250-2500 mm.

The technical scheme is further improved, the rolling mill is a double-roller rolling mill, and the upper working roll and the lower working roll are in variable-speed connection through gears, so that the roll surfaces of the upper working roll and the lower working roll have the same linear speed during rolling.

The technical scheme is further improved, the rolling mill is a double-roller rolling mill, and the upper working roll and the lower working roll are respectively driven by frequency modulation motors or servo motors with different rotating speeds, so that the roll surfaces of the upper working roll and the lower working roll have the same linear speed during rolling.

According to the technical scheme, the rolling mill is provided with a plurality of supporting rolls, and the supporting rolls are used for abutting against the upper working roll and the lower working roll and enabling the roll surfaces of the upper working roll and the lower working roll to have the same linear speed during rolling.

Due to the adoption of the technical scheme, compared with the background technology, the utility model has the following beneficial effects:

for foil rolling with a thickness below 0.3mm, the rolling is basically zero roll gap rolling, and the thinning is very difficult, which is a main problem to be solved. The utility model adopts the small-diameter working roll to thin the band foil, adopts the large-diameter working roll to ensure that the band foil obtains better plate shape, and considers the thinning function and the plate shape requirement of the band foil. The problem caused by the small rigidity of the small-diameter working roll is a secondary problem, and the problem can be solved by pressing the supporting roll to improve the rigidity of the working roll. Therefore, in general, the rolling scheme using the unequal-diameter working rolls is beneficial to reducing the thickness of the strip foil and obtaining better plate shape, which is particularly important for high-precision rolling of wide and thin strip foils.

The utility model realizes the high-precision rolling of the strip foil, particularly the wide and thin strip foil with the thickness of less than 0.3mm, breaks through the cognition of technicians in the industry on the working roller, breaks through the technical bottleneck, and provides a new technical solution for the rolling of the wide and high-precision strip foil.

Drawings

Fig. 1 is a schematic view of a conventional rolling mill.

Fig. 2 to 3 are schematic structural views in example 1 of the present invention.

Fig. 4 is a schematic structural view in embodiment 2 of the present invention.

Fig. 5 is a schematic structural view in embodiment 3 of the present invention.

In the figure: 1. a small diameter work roll; 2. a large diameter work roll; 3. a tape foil; 4. a material deformation core layer; 5. an upper work roll; 6. a lower working roll; 7. an upper driven gear; 8. a lower driven gear; 9. a driving gear; 10. a reversing gear; 11. an upper supporting roller; 12. a lower support roll; 13. an upper intermediate roll; 14. and (4) a lower intermediate roller.

Detailed Description

Preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only for explaining the technical principle of the present invention, and are not intended to limit the scope of the present invention. It should be noted that in the description of the present invention, the terms of direction or positional relationship indicated by the terms "front", "rear", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, which are for convenience of description only, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

Example 1:

a rolling mill with unequal diameter working rolls is used for rolling copper strips 3 with the thickness of 1.5mm and the width of 1200 mm. As shown in fig. 2, the rolling mill is a two-roll rolling mill, and includes an upper work roll 5 and a lower work roll 6, wherein the roll diameter of the upper work roll 5 is 300mm, the roll diameter of the lower work roll 6 is 600mm, and the roll diameter of the lower work roll 6 is 2 times the roll diameter of the upper work roll 5. The effective roll surface widths of the upper working roll 5 and the lower working roll 6 are both 1500 mm.

In order to ensure the stability of the material deformation center layer 4 and prevent the upper and lower plate surfaces from curling due to the difference of the rolling linear speeds, the rolling linear speeds of the upper working roll 5 and the lower working roll 6 are the same. In order to achieve the same linear speed of the roll surfaces of the upper working roll 5 and the lower working roll 6 during rolling, as shown in fig. 3, the upper working roll 5 and the lower working roll 6 are connected through a gear change so that the roll surfaces of the upper working roll 5 and the lower working roll 6 have the same linear speed during rolling. Specifically, the driven gear connected to one end of the upper working roll 5 is an upper driven gear 7, the driven gear connected to one end of the lower working roll 6 is a lower driven gear 8, and the number of teeth of the lower driven gear 8 is 2 times that of the upper driven gear 7. The lower driven gear 8 is meshed with the driving gear 9, and the driving gear 9 is driven by the main motor and the speed reducer. In order to rotate the upper working roll 5 and the lower working roll 6 in opposite directions, the upper driven gear 7 is engaged with the driving gear 9 through the reversing gear 10. As can be seen from fig. 3, when the driving gear 9 rotates, the driving gear drives the upper driven gear 7 and the lower driven gear 8 to rotate in opposite directions, wherein the rotation speed of the upper driven gear 7 is twice as high as that of the lower driven gear 8. Since the roll diameter of the lower work roll 6 is 2 times the roll diameter of the upper work roll 5, the roll surfaces of the upper work roll 5 and the lower work roll 6 can be made to have the same linear velocity during rolling.

The mode that the roll surfaces of the upper working roll 5 and the lower working roll 6 have the same linear speed through gear speed change needs to be provided with a driven gear set with corresponding gear ratio according to the roll diameter ratio of the upper working roll and the lower working roll, and meanwhile, the structure of the rolling mill and the adjustment difficulty of roll gaps are increased. With the development of motor control, the variable frequency motor adopting a frequency converter can realize the adjustment of the rotating speed, and the servo motor adopting a driver realizes the high power, so that the variable frequency motor or the servo motor can respectively apply different rotating speeds to the upper working roll 5 and the lower working roll 6, so that the roll surfaces of the upper working roll 5 and the lower working roll 6 have the same linear speed.

As is clear from fig. 2, the upper work roll 5 has a small roll diameter, a short rolling arc, and a large amount of press-fitting into the strip foil 3, and is advantageous for thinning the strip foil 3, and the total number of passes of rolling can be reduced. However, the rigidity of the upper working roll 5 is low, the lateral bending tendency is high, and the lubricating medium is not favorably and uniformly brought into a roll gap, so that the defect of plate shape of the upper plate surface of the band foil 3 is caused. The lower working roll 6 has high rigidity, small lateral bending tendency and long calendering arc length, and is beneficial to the uniform introduction of a lubricating medium into a roll gap, so that the lower plate surface with the foil 3 obtains a better plate shape. However, the lower work roll 6 has a large roll diameter and a small amount of press-fitting into the band foil 3, which is disadvantageous for thinning the band foil 3. It can be seen that the present invention combines the advantages of large diameter work rolls and small diameter work rolls: compared with the traditional working roll with the same diameter as the upper working roll 5, the increase of the roll diameter of the lower working roll 6 is beneficial to obtaining better plate shape; compared with the traditional working roll with the same diameter as the lower working roll 6, the reduction of the roll diameter of the upper working roll 5 has large pressing amount to the band foil 3, thus being beneficial to the rolling thinning of the band foil 3. Accordingly, the present invention also focuses on the disadvantages of large diameter work rolls and small diameter work rolls: the increase in the diameter of the lower work roll 6 compared to a conventional work roll having the same diameter as the upper work roll 5 is not advantageous for thinning the band foil 3. The reduction in the diameter of the upper work roll 5 is detrimental to obtaining a better profile shape, compared to a conventional work roll having the same diameter as the lower work roll 6. The strip foil 3 has better plate shape on one surface rolled by the lower working roll 6; and the shape of the rolled surface of the band foil 3 by the upper working roll 5 is poor, which affects the overall shape quality of the band foil 3.

Aiming at the defects, the following methods can be adopted to overcome the defects, and the core is as follows: before the strip foil 3 is rolled in the next pass, the strip foil 3 is turned over, and then the turned strip foil 3 is sent to a rolling mill for rolling. For rolling of non-ferrous metals, all the strip foils 3 need to be rolled repeatedly in multiple passes to achieve gradual thinning. In the conventional rolling methods, the strip foil 3 is not turned over, that is, the upper working roll 5 always rolls the upper plate surface of the strip foil 3, and the lower working roll 6 always rolls the lower plate surface of the strip foil 3. The rolling method adopts turn-over rolling, and the turn-over rolling is different from the prior rolling in that the plate surfaces of the band foils 3 rolled by the upper working roll 5 and the lower working roll 6 are different in two adjacent passes of rolling. For rolling of unequal diameter working rolls, the reduction amount of one surface rolled by the small diameter working roll is large, but the plate shape is poor; and the surface rolled by the large-diameter working roll has small reduction amount, but the plate shape is better. The strip foil 3 is rolled in a turn-over manner, so that the large-diameter working roll repairs the plate shape of the side with the deteriorated plate shape, and the small-diameter working roll thins the side with the better plate shape in a larger amount. Therefore, the rolling defects of the unequal-diameter working rolls are overcome on the premise of not changing the rolling advantages of the unequal-diameter working rolls. In order to ensure the consistency of the upper and lower rolling surface performances of the strip foil 3, the total rolling pass of the strip foil 3 is even number of times.

In conclusion, the rolling mill with the working rolls with different diameters is adopted for rolling the strip foil 3, so that the thinning of the strip foil 3 is facilitated, better plate shape is obtained, and the cognition of the technical personnel in the field on the working rolls of the rolling mill is broken through. By the turn-over rolling, the defects caused by rolling with unequal-diameter working rolls are overcome, and the wide-width high-precision rolling of the band foil 3 is realized.

Example 2:

a rolling mill with unequal diameter work rolls, different from example 1, was used for rolling copper strip foil 3 with a thickness of 0.8mm and a width of 1000mm, and the rolling mill used was a four-high rolling mill.

As shown in fig. 4, the rolling mill includes an upper work roll 5 and a lower work roll 6, wherein the roll diameter of the upper work roll 5 is 40mm, the roll diameter of the lower work roll 6 is 120mm, the roll diameter of the lower work roll 6 is 3 times of the roll diameter of the upper work roll 5, and the effective roll surface widths of the upper work roll 5 and the lower work roll 6 are both 1200 mm.

In order to increase the support of the work rolls and the rigidity of the work rolls, an upper support roll 11 is pressed against the upper work roll 5, a lower support roll 12 is pressed against the lower support roll 12, and the roll diameters of the upper support roll 11 and the lower support roll 12 are both 400 mm. In order to realize the same linear speed of the roll surfaces of the upper working roll 5 and the lower working roll 6 during rolling, the upper supporting roll 11 and the lower supporting roll 12 are driven by the same motor and speed reducer, so that the roll surfaces of the upper supporting roll 11 and the lower supporting roll 12 have the same linear speed, and further the roll surfaces of the upper working roll 5 and the lower working roll 6 have the same linear speed.

As can be seen from fig. 4, in the present embodiment, by using the supporting rolls, the rigidity of the upper work roll 5 and the lower work roll 6 is increased, and the roll diameter ratio of the lower work roll 6 to the upper work roll 5 is increased, which is beneficial to both the thinning of the band foil 3 and the obtaining of a better plate shape as a whole, and has a better implementation effect than that of embodiment 1.

Example 3:

a rolling mill with unequal diameter work rolls, different from example 2, was used for rolling copper strip foil 3 with a thickness of 0.1mm and a width of 800mm, and the rolling mill used was a six-roll mill.

As shown in fig. 5, the rolling mill includes an upper work roll 5 and a lower work roll 6, wherein the roll diameter of the upper work roll 5 is 30mm, the roll diameter of the lower work roll 6 is 120mm, the roll diameter of the lower work roll 6 is 4 times of the roll diameter of the upper work roll 5, and the effective roll surface widths of the upper work roll 5 and the lower work roll 6 are both 1000 mm. In the embodiment, the roll diameter of the upper working roll 5 is further reduced, the roll diameter ratio of the lower working roll 6 to the upper working roll 5 is further increased, and the advantages of the unequal-diameter working rolls are enhanced.

In order to further increase the support of the working rolls and the rigidity of the working rolls, an upper middle roll 13 is pressed on the upper working roll 5, and two upper supporting rolls 11 are pressed on the upper middle roll 13; a lower intermediate roller 14 is pressed under the lower support roller 12, and two lower support rollers 12 are pressed under the lower intermediate roller 14. The roll diameters of the upper middle roll 13 and the lower middle roll 14 are both 180mm, and the upper middle roll 13 and the lower middle roll 14 are used for pressing and driving the upper working roll 5 and the lower working roll 6 respectively; the upper support roll 11 and the lower support roll 12 both have a roll diameter of 350mm, and the upper support roll 11 and the lower support roll 12 are used for pressing the upper intermediate roll 13 and the lower intermediate roll 14, respectively. In order to realize the same linear speed of the roll surfaces of the upper working roll 5 and the lower working roll 6 during rolling, the upper intermediate roll 13 and the lower intermediate roll 14 are driven by the same motor and speed reducer, so that the roll surfaces of the upper working roll 5 and the lower working roll 6 have the same linear speed.

As can be seen from fig. 5, in this embodiment, by using the intermediate roll and the backup roll, the rigidity of the upper work roll 5 and the lower work roll 6 is further increased, and the roll diameter ratio of the lower work roll 6 to the upper work roll 5 is further increased, which is more favorable for the thinning of the strip foil 3 as a whole, and is also more favorable for obtaining a better plate shape, and the better implementation effect is achieved than that of embodiment 2.

In summary, the rolling of strip foil using unequal diameter working rolls has advantages and disadvantages, but for rolling of strip foil with a thickness of 0.3mm or less, the rolling is basically zero roll gap rolling, and the reduction is very difficult, which is a main problem to be solved. The most effective thinning measure is to reduce the roll diameter of the working roll, the smaller the roll diameter of the small-diameter working roll is, the more favorable the thinning of the strip foil is, and the larger the roll diameter ratio of the large-diameter working roll to the small-diameter working roll is, the more favorable the better plate shape is obtained. The problem caused by the small rigidity of the small-diameter working roll is a secondary problem, and the problem can be solved by pressing the supporting roll and improving the rigidity of the small-diameter working roll. Therefore, in general, the rolling scheme using the unequal-diameter working rolls is beneficial to reducing the thickness of the strip foil and obtaining better plate shape, which is particularly important for rolling wide high-precision metal strip foils.

The present invention is not described in detail in the prior art. Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the utility model, the scope of which is defined in the appended claims and their equivalents.

Claims (3)

1. A rolling mill with unequal-diameter working rolls is used for rolling metal strip foils and comprises an upper working roll and a lower working roll, and is characterized in that: the roll diameter of the upper working roll is smaller than that of the lower working roll, and the upper working roll and the lower working roll are in variable-speed connection through gears or are respectively driven by frequency modulation motors or servo motors with different rotating speeds, so that the roll surfaces of the upper working roll and the lower working roll have the same linear speed during rolling.

2. A rolling mill having work rolls of unequal diameters as claimed in claim 1 wherein: the diameter of the lower working roll is 1.5-5 times of that of the upper working roll.

3. A rolling mill having work rolls of unequal diameters as claimed in claim 2 wherein: the diameter of the upper working roll is 25-100 mm.

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