WO2011061165A2

WO2011061165A2 - Cooling and cleaning of strip processing lines

Info

Publication number: WO2011061165A2
Application number: PCT/EP2010/067526
Authority: WO
Inventors: Arthur Allerdings
Original assignee: Sms Siemag Ag
Priority date: 2009-11-21
Filing date: 2010-11-16
Publication date: 2011-05-26
Also published as: EP2501498A2; DE102009054205A1; ES2538006T3; WO2011061165A3; EP2501498B1

Abstract

The invention relates to a method for cooling and cleaning in casting plants, rolling mills or other strip processing lines, wherein casting products, rolling stock (17) or plant components (11, 12, 13, 14, 15, 16) are simultaneously cooled and cleaned by a gas-liquid mixture and are eventually lubricated and sealed. The invention further relates to a corresponding rolling mill and/or processing line. The invention thus allows to overcome the disadvantages of cleaning simply with gas and those of cooling and cleaning using liquid emulsions.

Description

Cooling and cleaning in belt process

Field of the invention

The invention relates to the cooling and cleaning of components and products in belt processing plants or lines, especially in rolling mills and casting plants.

State of the art

On the one hand, rolling plants are known from the prior art in which a liquid is used for cooling and / or for cleaning the rolls, the rolls and the rolling stock. Also for the lubrication of a roll gap, a liquid is usually used. These are usually emulsions of water and oil. Liquids, in particular water, have good heat-dissipating properties, which can be further increased by an initial temperature difference relative to the material to be cooled or by the flow speed of the liquids. Also, the cleaning properties are often given in a sufficient degree. The disadvantage, however, is the great moisture or moisture, as a result of this method in belt processing systems, in particular in the roll stand and on the rollers, or present on the rolling stock. On the one hand, this wetness can lead to increased corrosion of various materials and on the other hand generally adversely affect the quality of the rolling stock and its further processing. Another disadvantage of using an emulsion as such is that it usually has to have a temperature of at least 50 ° C. to 60 ° C., so that it emulsifies sufficiently and has the desired lubricating properties. The necessarily higher temperature of the emulsion is opposed to the cooling. Furthermore, a constant filtration of the emulsion is usually necessary.

For example, International Publication WO 2005/1 20739 discloses a method and a rolling stand for cold rolling metallic stock. In this device, for a nozzle for gaseous media are provided and installed on the other nozzle for liquid treatment media in the rolling stand. In particular, individual nozzle rows are directed against the rolling gap or against the rolling stock for lubricating, cleaning and cooling. In this case, an M is also used in imalmengen lubrication. This means that oil is applied in small quantities to the rolling stock. This can be understood that the rolling stock usually has a surface roughness in the micrometer range and the amount, as described in the cited publication, is chosen so that just this roughness is compensated by a thin lubricant film. The quantities of oil used per square meter of rolling stock are known to be in the milligram range. These small amounts used can thus be neither the cooling nor the cleaning of the product useful. Furthermore, WO 2005/1 20739 proposes to apply cryogenic inert gas, in particular liquid nitrogen. However, the use of such cryogenic gases as nitrogen is on a large scale Scale expensive. This is due, among other things, to the fact that they are required, on the one hand, in some considerable quantities, in the operation of such a plant and, in addition, cause increased costs for its storage, transport and occupational safety.

As is known, pure air is used for cleaning in rolling plants. The air is particularly helpful in the drying of parts of the device or the rolling stock. However, the disadvantage is the poor heat-dissipating properties of the air.

Accordingly, although methods for cooling and cleaning in strip processing lines, in particular in rolling mills, are known from the prior art, but these have the disadvantages described above.

Therefore, the technical problem of overcoming at least one of the above-mentioned disadvantages or to further develop the known methods and / or devices.

Disclosure of the invention

The present technical problem is solved by the method and apparatus of the invention. The invention comprises a Method for cooling and for cleaning in casting plants, rolling mills or other strip processing plants, wherein castings, rolling stock or other components of the plants are simultaneously cooled, lubricated and cleaned by a gas-liquid mixture. In contrast to the methods of the prior art described above, according to the invention gas and liquid are simultaneously cleaned and cooled. This creates several advantages. The fact that gas and liquid are applied simultaneously, the disadvantage of cleaning with clean air is overcome, since the coexisting liquid ensures good cooling properties. On the other hand, the disadvantages of pure liquid cooling are overcome, with their biggest disadvantage is that it creates a large amount of moisture or moisture on the rolling or plant components, the quality of the rolling stock and its further processing, or the durability of the plants negative affected. In particular, the strip flatness can be improved according to the invention, as can the mechanical intrinsic properties, such as grain sizes or yield strengths. In addition, an improvement in the produced strip surface is also possible, such as allowing less roughness and greater cleanliness.

In an advantageous embodiment of the invention, both the gas and the liquid of the gas-liquid mixture are co-exuded for cooling and cleaning. This means that both the gas and the liquid are applied from a common location to the rolling stock or to a part of the plant. This means, for example, that the gas-liquid mixture is emitted by means of a common nozzle or generally by means of a common outlet. Of course, preferably also several such nozzles or outlets may be provided. From there, reaches the gas-liquid mixture flow to the rolling stock or the plant. In particular, it is thus also possible to apply a mist of liquid and gas, which means in particular that there are droplets of the liquid in the gas.

In a further preferred embodiment of the method, air, in particular compressed air, is used as the gas of the gas-liquid mixture. By using compressed air, the cleaning effect and cooling effect can be further improved.

In a further preferred embodiment of the method, water, ethanol, kerosene or oil is used as the liquid of the gas-liquid mixture. In particular, the use of kerosene or ethanol increases the cooling and cleaning effect, since these substances evaporate quickly and require phase transformation heat, so that their phase transition from the liquid phase into the gaseous phase for the warm rolling or warm plant components, a significant temperature reduction occurs ,

In a further preferred embodiment of the method, the gas or air of the gas-liquid mixture is set in motion by a fan or a compressor. This can be controlled depending on the specific application, whether the mixture slowly moves in the form of a slowly moving mist on the corresponding material or in the form of a faster moving jet, in particular compressed air jet, meets the object to be cooled and cleaned. In a further preferred embodiment of the method, the gas-liquid mixture additionally contains solids. These solids or solids, such as ice crystals or solid phases of other gases or liquids, which liquefy and / or evaporate on contact with the rolling stock, can further increase the cleaning effect and / or the cooling effect. On the one hand, the cleaning effect is enhanced by a ballistic effect, that is to say by the impact of the solids or particles on the surface of the rolling stock or of the plant component. On the other hand, the phase transitions from solid to liquid and possibly from liquid to gaseous lead to additional temperature reductions of the material to be cooled due to the necessary evaporation or sublimation heat in the phase transitions.

In a further preferred embodiment of the method, a gas mixture is used as the gas of the gas-liquid mixture and / or a liquid mixture is used as the liquid. Depending on the application, a plurality of gases or liquids can also be used simultaneously for cooling and cleaning or can be flowed together, whereby a uniform cooling of the material to be cooled can be achieved, inter alia, by different phase transition temperatures of the liquids used and not the entire liquid at a certain Temperature evaporates. The quality of the tape can be further increased. In a further preferred embodiment of the method, the gas-liquid mixture optionally comprises one or more of the following components: gaseous nitrogen, liquid nitrogen, air, argon, water, demineralized water, oil, ethanol, kerosene.

In a further preferred embodiment, the method is carried out in a rolling mill for rolling a metal strip, which comprises at least one pair of rollers or rollers between which the metal strip passes, wherein the cooling and the cleaning and possibly also the lubrication through the gas-liquid mixture the inlet side of a roller and / or on the outlet side of a roller, takes place on the inlet side of the roller pair and / or on the outlet side of the roller pair and / or below the metal strip and / or above the metal strip. Due to the good both cleaning and cooling properties of the method according to the invention, it can be found in particular in many places a rolling mill application. The methods known from the prior art do not allow such a flexible application.

In a further preferred embodiment of the method, the gas-liquid mixture is generated by accelerating the gas or the liquid subsequently introduced into a gas stream before it leaves a common outlet or a common nozzle.

In addition to the method already mentioned, the invention comprises a rolling system for rolling a metal strip, in particular for carrying out the above-mentioned method, which comprises at least one pair of rolls or rolls. zenpaar, between which the metal strip passes and which further comprises at least one gas-liquid mixture outlet, which is designed for simultaneous flow of the gas-liquid mixture. Such a system has substantially the same advantages as the method described above.

In a preferred embodiment of the rolling plant, the gas-liquid mixture outlet is formed by a nozzle or by an outlet pipe of a spray bar.

Brief description of the figures

In the following, a figure of an embodiment will be briefly described. Further details can be found in the detailed description of the embodiments.

Figure 1 shows schematically an embodiment of the method according to the invention, wherein at several points of a rolling mill at the same time a gas-liquid mixture is emitted.

Detailed description of the embodiments Figure 1 shows schematically an embodiment of the present invention. First, it should be noted that this illustrated embodiment may not be construed restrictive but only the multiple application possibilities of the method according to the invention is intended purely by way of example.

In particular, in the figure, several outlets 1 to 10 for a gas-liquid mixture for cooling and cleaning a metal strip 17 and / or a rolling mill with rollers 12 to 15 and rollers 16 are shown. The gas-liquid mixture is shown schematically by the black triangles or Sprühfächer. In the exemplary embodiment, in particular a rolling stand 1 1 with two support rollers 1 2, 15 and intermediate work rolls 13, 14 is shown. The work rolls 13, 14 exercise, as usual, a rolling force on the rolling stock 17, which moves according to the figure 1 from left to right. The left side of the frame 1 1 corresponds to the inlet side of the frame 1 1, the right side of the frame 1 1 corresponds to the outlet side.

Despite the large number of outlets 1 to 10 shown, it is also conceivable to provide an outlet for the gas-liquid mixture only at one of the positions 1 to 10 shown. However, it is also possible that the outlets 1 to 10 are provided for the gas-liquid mixture at other positions, as they are already known in rolling plants or in casting plants or other belt processing plants. It is also possible for the gas-liquid mixture to be used for cleaning and cooling as well as possibly for lubrication and surface sealing of processing tools and / or other workpieces of the installations. It is in particular also possible that a gas-liquid mixture is simultaneously exuded by a plurality of said outlets. Regardless, however, it is preferably the case that the gas-liquid mixture is emitted from at least one outlet together. An outlet may be, for example, a nozzle or an outlet opening of a spray bar. The gas-liquid mixture can also be sprinkled or sprayed simultaneously from a row of nozzles, which preferably extends parallel to a roll axis or extends perpendicular to the rolling or casting direction.

The gas-liquid mixture may preferably be composed as follows: As the gas of the gas-liquid mixture, in particular air, optionally also under pressure, that is compressed air, may be used. The air can be moved by a fan or a compressor. As part of the liquid speed of the gas-liquid mixture are in particular water, ethanol, kerosene or oil use. Advantageously, the gas-liquid mixture additionally contains solids or solids. These may be natural solids of the air, such as ice crystals or may be formed by other added solids. In addition, a gas mixture can be used as the gas of the gas-liquid mixture and / or a liquid mixture can be used instead of a single liquid of the gas-liquid mixture. Other gases and liquids or components or substances used can be, for example, gaseous nitrogen, liquid nitrogen, argon or demineralized water. The construction of corresponding outlets which serve to carry out the method according to the invention is known to the person skilled in the art. In particular, but not exclusively, the method is applicable to both hot and cold rolling mills.

LIST OF REFERENCE NUMBERS

1 left, outer gas-liquid mixture outlet, above the rolling stock

2: left, outer gas-liquid mixture outlet, below the rolling stock 3: on the input side, arranged above the rolling stock and directed to the work rolls gas-liquid mixture outlet

4: inlet gas side below the rolling stock and directed to the work rolls gas-liquid mixture outlet

5: on the outlet side above the rolling stock on the roll gap directed gas-liquid mixture outlet

6: on the outlet side below the rolling stock on the roll gap directed gas-liquid mixture outlet

FIG. 7: gas-liquid mixture outlet 8 directed outwards of the rolling stock on the work roll and the supporting roll 8: gas-liquid mixture outlet directed downstream of the rolling stock on the work roll and the supporting roll

9: Gas-liquid mixture outlet for cooling and cleaning a roll

10: right, outer, lying above the rolling gas-liquid mixture outlet 1 1: rolling stand

12: upper support roller 13: upper work roll 14: lower work roll 15: lower backup roll 16: roll

17: rolling stock

Claims

claims

1 . Process for cooling and cleaning in casting plants, rolling mills or other strip processing plants, wherein casting products, rolling stock (17) or components of the plants (1 1, 12, 13, 14, 15, 16) simultaneously cooled and cleaned by a gas-liquid mixture, preferably also lubricated and / or sealed.

2. The method of claim 1, wherein both the gas and the liquid of the gas-liquid mixture are co-exuded for cooling and cleaning.

3. The method of claim 1, wherein the gas of the gas-liquid mixture is air, in particular compressed air, is used.

4. The method of claim 1, wherein as a liquid of the gas-liquid mixture, for. As water, ethanol, kerosene or oil is used.

5. The method of claim 1, wherein the gas of the gas-liquid mixture is caused by a fan or a compressor in motion.

6. The method of claim 1, wherein the gas-liquid mixture additionally contains solids.

7. The method according to any one of the preceding claims, wherein a gas mixture is used as the gas of the gas-liquid mixture and / or a liquid mixture is used as a liquid.

The process of claim 1 or 7, wherein the gas-liquid mixture optionally comprises several of the following components: for example, gaseous nitrogen, liquid nitrogen, air, argon, water, demineralized water, oil, ethanol, kerosene.

The method according to one of the preceding claims, wherein the method is carried out, for example, in a rolling mill for rolling a metal strip (17) comprising at least one pair of rolls or rolls (13, 14; 12, 15) between which the metal strip (17 ), wherein the cooling and the cleaning by the gas-liquid mixture on the inlet side of the roller pair (1, 2, 3, 4) and / or on the outlet side of the roller pair (5, 6, 7, 8, 9, 10) and / or below the metal strip (2, 4, 6, 8, 9) and / or above the metal strip (1, 3, 5, 7, 10) and / or on the inlet side of the roller (16) and / or on the outlet side of the roller (16).

The method of claim 1, wherein the gas-liquid mixture is generated by acceleration of the gas or the liquid nach- is introduced into a gas stream before the gas-liquid mixture together has an outlet (1, 2, 3, 4, 5, 6, 7, 8, 9,

10).

1 1. A rolling mill for rolling a metal strip (17), in particular for carrying out the method according to one of the preceding claims, which comprises at least one pair of rolls or roller pairs (13, 14; 12, 15) between which the metal strip (17) passes and which furthermore at least one gas-liquid mixture outlet (1, 2, 3, 4, 5, 6, 7, 8, 9, 10), which is designed for the simultaneous flow of a gas-liquid mixture.

12. The rolling plant according to claim 11, wherein the gas-liquid mixture outlet (1, 2, 3, 4, 5, 6, 7, 8, 9, 10) is formed by a nozzle or by an outlet pipe of a spray bar ,