RU2296633C1 - Linear mill for lengthwise rolling - Google Patents

Abstract

FIELD: production of rolled stock in linear bar rolling mills.

SUBSTANCE: linear rolling mill having group of two-high stands joined with main drive unit through transmissions is provided with common reduction gear mounted between said group of two-high stands and transmission of main drive unit. Common reduction gear includes pairs of pinion rolls joined with working rolls of two-high stands and with transmission of main drive unit. Pairs of pinion rolls of common reduction gear are joined with transmission of main drive unit through gears gradually lowering gear ratio values before each even-number two-high stand. Two-high stands are mounted in pairs at both sides of drive unit line and they form continuous groups. Rotation sign of rolls of one continuous group is opposite relative to rotation sign of rolls of other continuous group. Invention provides possibility for rolling in conditions almost the same as conditions of rolling in continuous mill.

EFFECT: improved quality of products, increased efficiency, lowered power consumption, reduced areas for mounting rolling equipment.

2 dwg, 1 ex

Description

The invention relates to the field of rolling production, and more specifically, to linear high-quality mills.

In Russia and abroad, at a number of enterprises, linear mills of small capacity are still in operation, serving small regions with high-quality products. As a rule, the equipment of such mills is already morally and physically outdated and requires replacement. The construction of modern continuous mills for such enterprises is not economically feasible, at the same time, the level of quality of products of linear mills, as a rule, does not satisfy the needs of the market.

Linear mills of longitudinal rolling are known (see Tselikov A.I., Smirnov V.V. Rolling mills. - M .: Metallurgizdat. - 1958, p. 18, Fig. 10d), containing several consecutive groups of stands with individual drives of each of them.

The disadvantage of such mills is the large installed power of the electric motors of the main drives and the difficulty of setting up the mill, associated with the need to coordinate rolling speeds in different groups.

Known linear mill for longitudinal rolling, described in RF patent N 2033868, 21 V 1/08, 1995.

This linear mill contains a group of twin roll stands connected to each other in series by means of spindles, and a group electric drive. This mill is easy to set up. In addition, it has low installed power due to the use of one engine to drive all stands.

A disadvantage of the known construction of the linear mill is that the same number of revolutions of the rolls of the stands of the linear group leads to unreasonably high rolling speeds in the first passes of the intermediate or finishing groups of the stands, which leads to increased resistance to deformation of the metal in these stands and, accordingly, to increased efforts and moments of rolling compared to a continuous mill.

Of the known longitudinal rolling mills, the closest in technical essence is the linear mill described in the patent of the Russian Federation No. 2155644, 21 V 1/08, 1995

This linear mill contains a group of stands connected to the main drive by means of a transmission and gearboxes located between each stand and transmission of the main drive with gear ratios gradually decreasing during rolling, which ensure the metal entry speed into each of the subsequent stands lower than the metal exit speed from the previous stand by 1 -10%.

The disadvantage of this design is the need for additional areas along the width of the span of the workshop to accommodate along the main transmission of the mill all twin roll stands equipped with individual gearboxes.

This drawback does not allow the use of this design of the mill for the modernization of most obsolete large-grade linear mills installed in buildings with narrow camp spans.

The objective of the present invention is to create a linear longitudinal rolling mill, which allows to improve product quality by obtaining high stability along the length of the roll, both in terms of geometric and structural characteristics of metal, increase mill productivity by increasing the speed at the exit from the group of stands, and reduce energy consumption per ton of long products, reduce production facilities.

The problem is achieved in that a linear mill of longitudinal rolling, containing a group of twin roll stands connected to the main drive via a transmission, according to the invention is equipped with a common gearbox including pairs of gear rolls connected to the work rolls of the twin roll stands and with the transmission of the main drive, while pairs of gears rolls with transmission of the main drive are connected by gears, gradually reducing gear ratios in front of each even two-roll stand along the way rolling two roll stands arranged in pairs on both sides of the drive line, forming a continuous band, but the direction of roll rotation of one continuous band opposite to the direction of rotation of the rolls another continuous group ..

Such a constructive implementation of a linear mill will allow, providing a gradual increase in rolling speeds from one stand to another, to reduce or maintain the production area of the mill through the use of only one common gearbox for all two-roll stands.

To explain the invention, a specific embodiment of the invention is provided below with reference to the accompanying drawings, in which:

figure 1 shows the layout of the equipment of a linear mill of longitudinal rolling;

figure 2 shows a section aa in figure 1

The linear mill of longitudinal rolling consists of a crimping stand of trio 1, a roughing stand of trio 2, a group of twin roll stands duo 3, 4, 5, 6, a common gearbox 7 with an input shaft 8, output shafts 9 and pairs of gear rolls 10. The gearbox 7 is input shaft 8 through a common transmission 11 is connected to the main drive 12. Gear rolls 10 through the output shafts 9 of the gearbox 7 are connected to the work rolls of the stands duo 3, 4, 5, 6, and gears 13 with the input shaft 8 of the gearbox 7. Two-roll stands 3, 4 and 5, 6 are arranged in pairs in continuous groups on either side of line n mill drive, while the direction of rotation of the rolls of one continuous group is opposite to the direction of rotation of the rolls of another continuous group.

The arrows in Fig. 1 show the rolling direction.

The mill works as follows.

After ordinary rolling, the metal in trio stands 1 and 2 is sent for rolling in series to twin roll stands 3 and 4, and then to twin roll stands 5 and 6. Rolling speeds in twin roll stands 3, 4, 5, 6 are determined by the ratio of gear ratios in the general gearbox in the range from 1.1 to 1.3, at which the rolling speed in the stands increases from 3 to 4 and from 5 to 6, with an additional increase in the indicated rolling speeds by 5 ... 30% due to the fact that the nominal the diameters of the rolls of the two-roll stands of the duo is 0.8-1.2 of the nominal Nogo roll diameter roughing stand 2 trio.

The proposed linear mill in comparison with the known ones allows to obtain a process stream close to rolling on a continuous mill at the existing workshop areas with minimal capital costs and with the possibility of maintaining the existing electric drive, which, in turn, will increase the competitiveness of products.

Claims (1)

A linear rolling mill containing a group of double roll stands connected to the main drive by means of a transmission, characterized in that it is equipped with a common reducer located between the group of double roll stands and the transmission of the main drive, including pairs of gear rolls connected to the work rolls of the double roll stands and with the transmission of the main drive, while pairs of gear rolls are connected to the transmission of the main drive by gears, gradually reducing gear ratios per d each even-roll stand in the course of rolling, two roll stands arranged in pairs on both sides of the drive line, forming a continuous band, and the direction of rotation of the rolls one continuous band opposite to the direction of rotation of the rolls another continuous group.

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