WO2014174099A1

WO2014174099A1 - Method and rolling stand for cold rolling rolled stock

Info

Publication number: WO2014174099A1
Application number: PCT/EP2014/058503
Authority: WO
Inventors: Michael Breuer; Kerstin SPILL; Markus Fischer
Original assignee: Sms Siemag Ag
Priority date: 2013-04-26
Filing date: 2014-04-25
Publication date: 2014-10-30
Also published as: EP2988884A1; KR101737945B1; CN105142810A; US20160059283A1; JP2016531754A; KR20150139571A; DE102014207859A1; EP2988884B1

Abstract

The invention relates to a method and a rolling stand (100) for cold rolling rolled stock. The rolling stand (100) comprises at least one upper and one lower backup roll (110-1, 110-2) and also an upper and a lower work roll (120-1, 120-2), which define a roll gap (128). Optionally, a lower and an upper intermediate roll (130-1, 130-2) may also be provided between the work rolls and the backup rolls. In order to ensure an absolutely equal circumferential speed of the upper and lower work rolls when cold rolling in skin-pass mode, it is proposed according to the invention to decouple the upper or lower work roll from its associated drive device.

Description

Process and rolling stand for cold rolling of rolling stock

The invention relates to a method for operating a roll stand for cold rolling of rolling stock. The rolling stand comprises at least an upper and a lower support roll and an upper and a lower work roll, which span a roll gap. Optionally, a lower and an upper intermediate roll may also be provided between the work rolls and the support rolls. In addition to the method, the invention also relates to said roll stand. Roll stands and methods for their operation are basically known in the prior art, for example from EP 1 318 879 B1, DE 4417274 C2, EP 1 420 898 or DE 4417274. In addition, the topic of cooling or lubricant during cold rolling is discussed from rolling stock referenced to the following literature: DE 19744503 A1, EP 1 173 295, DE 10 2004 025058, EP 1 399 277 and DE 10 2007 0324857 (= WO 2008/071277), JP 620688613 A and Selzer, H., developments in the cold rolling range , Cold Rolling Symposium of SMS Siemag AG, Hilchenbach-Dahlbruch, DE, 16-17.02.2000.

In the prior art, a distinction is fundamentally made in rolling stands between reducing stands and temper rolling stands.

Reduziergerüste have the task to reduce per stitch 30 to 80% of the thickness of the rolling stock. At these high degrees of deformation occur high rolling forces and rolling moments. Therefore, a roller cooling with high efficiency is necessary. Here are up to 10,000 l / min. per mill converted to cooling amount. The work rolls in the reducing stand are of relatively smooth surface without special texturing. In Reduzierbetrieb the upper backup roller is on the upper intermediate roll and this in turn on the upper work roll on. If the intermediate roll is missing, as in the four-roll stand, then the upper support roll rests directly on the upper work roll. The rolling forces are in the range of 10 to 20 MN. The rolling moments are in a range of 100 up to 200 kNm. When reducing, a special thickness control is used, which can be operated both in the position control mode, as well as rolling force control mode. The essential actuator of the thickness control during reduction are almost exclusively the adjusting cylinders of the support rollers and only in peripheral areas of the strip tension.

Reducing stands can be in six-roller or four-roller design, d. H. be formed with six or four rollers. In Reduzierbetrieb typically both work rolls are rotated to transmit a rolling torque on both work rolls. Such reducers are known both for reducing iron metal and for reducing non-ferrous metal. The only noteworthy difference between the operation of ferrous metal and non-ferrous metal reducers is the use of the appropriate cooling lubricant; The cooling lubricant is a (number word) means with the two functions cooling and lubricating. For non-ferrous metal, in particular for aluminum, rolling oil is typically used as the cooling lubricant.

However, in addition to the pure reducing stands for ferrous metal and non-ferrous metal just described, pure skin pass mills are known only for iron metal. Dressing scaffolds have the task to impress a texture on the rolling stock, to improve the flatness and / or to improve the material properties of the rolling stock, for. B. Eliminate Lüders bands or adjust certain strengths. For embossing the texture on the rolling stock, therefore, the typically smooth work rolls are used by special temper rolling with a predetermined roughened surface. In the case of temper rolling, typically only a single pass is made with a rolling stock reduction of 0.3 to 10%. By imprinting the texture material abrasion occurs on the rolling stock, so-called tinsel, which has a disturbing effect on further processing and heavily contaminates the tempering medium. In the case of temper rolling, the rolling force and the rolling moment are in In comparison to a reduction operation very low, specifically, the rolling forces during the temper rolling range in a range of 1 to 4 MN. The rolling torques are typically in a range of 0 to 20 kNm. The applied amount of tempering agent is about 20 l / min. per side of the rolling stock at a significantly lower level compared to the reduction operation. The main task of the tempering agent is essentially the cleaning of the rolling stock or the rolls. During the temper rolling operation, typically neither of the two work rolls is driven; instead, only the lower support roller is driven, thus transferring a rolling moment to it. In the tempering operation, the rolling force can be applied either via the adjusting cylinder of the upper support roller; this presupposes, however, that the upper support roller rests either on the upper work roll or, if present, on the upper intermediate roll. Alternatively, the upper backup roll may also be lifted from the upper work roll or, if present, from the upper intermediate roll. Then, the application of the rolling force in the skin pass through a suitable employment of the upper bending cylinder, which act either on the upper work roll or - if present - on the upper intermediate roll. In addition to the pure Reduziergerüsten and pure tempering scaffolds just described there are also Kombigerüste, which can be operated both in a Reduzierbetrieb as well as in a temper mill, but only for ferrous metal, not for non-ferrous metal. The known pure non-ferrous metal reducing stands are not suitable for combined operation, ie for an alternative tempering operation for non-ferrous metal, because the reducing stands are designed for rolling forces that would be too great for a nonferrous metal tempering operation. The friction forces within the hydraulic adjustment are approximately proportional to the maximum force, that is, a pitch cylinder, which has been designed for high forces can not work due to its internal friction in the required accuracy at low rolling forces. In Reduziergerüsten usually two rollers, usually the work rolls driven to transmit the required rolling torque as evenly as possible in the nip. Smallest differences in diameter between the work rolls lead to moment differences between the rolls, which, however, do not have a detrimental effect on the rolling result, because the high decreases compensation in the rolling, eg by shearing, takes place.

In the case of temper rolling with small reductions / tempering degrees, this internal compensation can not take place because only near-product roll formations take place. In addition, the rolling moments are so low that the drive of only one roller is sufficient.

Based on this prior art, the present invention seeks to further develop a known method and a known rolling stand for cold rolling of rolling material operable in a reducing or a temper rolling operation, that the quality of the rolling stock and the stability of the rolling conditions are improved in the temper rolling. This object is achieved by the method claimed in claim 1. This method is characterized in that the upper or the lower work roll is uncoupled from its drive device in the temper rolling operation. Neither the upper nor the lower support roller are driven in the temper rolling operation according to the invention.

The term "or" is to be understood as an exclusive alternative in the context of the present invention A simultaneous decoupling of both work rolls in the temper rolling operation, as known in the prior art, is expressly not meant and excluded from the scope of protection. The introductory definitions of reducing operation and tempering operation apply - apart from the drive concept for the work rolls in the temper rolling operation - equally for the subject matter of the present invention. In contrast, the claimed drive concept applies to the drive of the work rolls in the skin pass mill.

The claimed method provides that the rolling stand can be operated as an alternative to the temper rolling in a mode of operation reducing operation for significantly reducing the thickness of the rolling stock. Such a composite scaffold, which allows ironing of ferrous and non-ferrous metals and reducing iron metal and non-ferrous metal on a scaffold, offers significant advantages, especially in financial terms compared to two separate scaffolds, ie. H. a Reduziergerüst and a separate skin pass mill.

Smallest diameter differences in the two work rolls, as they are z. B. by grinding errors or different thermal expansion and led to speed differences in the two work rolls are advantageously avoided by the claimed drive concept, in which the two work rolls are rotationally coupled to each other in the temper rolling on rolling stock together. Also moments-trim, chatter, surface defects and / or unstable rolling conditions, as they typically arise in a positive coupling of both work rolls to the comb-rolling gear, are advantageously avoided by the claimed drive of only one of the two work rolls. Overall, the quality of the rolling stock is improved and the rolling conditions stabilized by the claimed drive concept in the temper rolling. Thus, the claimed method is particularly suitable for casting non-ferrous metal strip. According to a first embodiment of the method according to the invention is in the tempering the upper support roller of the upper work roll or - if present - lifted from the upper intermediate roll and there is the application and adjustment of the rolling force by the action of the upper bending cylinder on the upper work roll or - if present - on the upper intermediate roll.

The power flow in the rolling stand and the characteristics of the components are essential for the elastic behavior of the roll stand. Games and lots should therefore be avoided, as a free movement of the very heavy components would cause damage within a short time. Therefore, all joints between moving components, such. B. between stacked bearing housings, d. H. Chocks, adjacent rolls balanced by means of hydraulic adjustment, d. H. biased. A back-up roll can weigh up to 200 t. This corresponds to a necessary balancing force of 2 MN. This corresponds to the same size as the required rolling force in the temper rolling operation. If then additionally an employment of the support rollers would be provided on the adjusting cylinder, the rolling force acting on the rolling stock would very quickly exceed the lower tempering required in the temper rolling. Also, the (lesser) temper rolling forces would no longer be able to be controlled cleanly, because the weight of the back-up roll alone is of the same order of magnitude.

Therefore, the lifting of the upper backup roll from the upper work roll or from the upper intermediate roll provided according to the first embodiment avoids the described problem of excessive rolling force when the backup roll rests.

Any side effects of lifting the backup roll, such as a possible change in the nip profile are remedied by the application and adjustment of the rolling force by the action of the upper bending cylinder on the upper work roll or, if present, on the upper intermediate roll, as claimed. In principle, in the context of the present invention, during the tempering operation, the upper support roller may also rest on the upper work roll or on the upper intermediate roll; then, however, the said disadvantages persist in the fine adjustment of the tempering forces.

According to a further embodiment, the method according to the invention provides that in the temper rolling operation the thickness of the rolling stock is regulated with the aid of a skin pass control loop to a predetermined constant nominal thickness, e.g. by suitable variation of the strip tension of the rolling stock or the rolling speed as manipulated variables. The skin level control, d. H. Thickness control during skin pass requires that the rolling force must be kept constant in order to obtain a uniform impression of the roughness of the temper rolling on the strip. It should be possible no thickness jumps occur. For this purpose, the method according to the invention advantageously provides for a regulation of the rolling force applied to the rolling stock with the aid of a rolling force control loop, the bending cylinders serving as actuators for the rolling force. Preferably, alternatively or additionally, a position control loop is provided in order to keep the setting position of the work rolls constant.

Both the rolling force control and the position control must be done in real time if possible, which is why the step responses of the two control loops preferably last less than 80 ms. According to a further embodiment, the method according to the invention provides that, optionally, a flatness control loop can also be provided for regulating the flatness of the rolling stock. The flatness control loop then comprises a flatness measuring device, z. B. a flatness measuring roller at the output of the rolling stand for detecting the actual flatness of the rolling stock. The actual flatness measured in this way is compared with a predetermined desired flatness, ie the difference between these two flatnesses is formed and this difference is calculated as Flatness control deviation fed to a flatness controller, which generates a suitable actuating signal for an actuator, for example, the upper bending cylinder of the upper intermediate or work roll, in accordance with the flatness control deviation. In this way, the bending cylinders are controlled in such a way that the flatness at the outlet of the roll stand ideally corresponds to the predetermined desired flatness.

According to a further embodiment of the invention, the lubricant is circulated and prefiltered after its use and before its reuse or prior to its recirculation. During its prefiltering, the lubricant is freed of tinsel particles that may be produced during the temper rolling operation. The prefiltering is preferably carried out before a typically anyway carried out very fine filtering of the lubricant. According to a further embodiment, it is provided that only a minimal amount of pure lubricant is used in the temper rolling operation. The minimum amount is ideally such a small amount that is completely consumed during the temper rolling in the nip, so that in the outlet of the rolling stand ideally no lubricant remains on the surface of the rolling and no lubricant runs off the side of the rolling stock. This minimal quantity lubrication basically takes place alternatively to the recycling of the lubricant, as described in the previous paragraph. If, in the reality of minimal quantity lubrication, small residual amounts of lubricant nevertheless remain on the rolling stock, these residual quantities can, of course, still be circulated and reused after prefiltering.

The inventive method is provided for non-ferrous metal strip or ferrous metal strip as a rolling stock. When tempering non-ferrous metal strip as rolling stock, rolling oil is preferably used as lubricant, taking advantage of its lubricant function. Basically, rolling oil however, in all modes of operation, that is, both for reducing non-ferrous metal strip or ferrous metal strip, as well as for tempering non-ferrous metal strip or ferrous metal strip. In the temper rolling operation according to the present invention, temper rolling rolls, typically with a certain surface roughness, are used as work rolls. These temper rolling are advantageously cleaned during the breaks of the tempering operation by a high-pressure spray with the lubricant or with the aid of brushes. The cleaning process has the advantage that the service life of the temper rolling specially roughened for the temper rolling is increased.

The above object is further achieved by a rolling stand according to claim 1 1. This solution is characterized in that the torque transmission device has at least one coupling device and an associated control device for uncoupling the upper or the lower work roll from the at least one drive device during the tempering operation. The advantages of this solution correspond to the advantages mentioned above with reference to the method described.

Further advantageous embodiments of the method and the rolling mill according to the invention are the subject of the dependent claims. The description is a total of three figures attached, where

Figure 1 is an inventively designed four-roll mill stand;

Figure 2 is an inventively designed six-high rolling stand; and Figure 3 shows the inventive method for setting a Reduzierbetriebs or temper rolling on a combination mill.

The invention will be described in detail below with reference to the said figures in the form of exemplary embodiments. In all figures, the same technical elements are designated by the same reference numerals. Figure 1 shows a four-roll mill 100. Specifically, the mill stand comprises an upper work roll 120-1, a lower work roll 120-2, and an upper backup roll 1 10-1 and a lower backup roll 1 10-2. The work rolls are arranged between the two support rolls. In rolling operation, the two work rolls clamp a nip 128 in order to cold-roll the rolling stock between them.

On the inlet side of the rolling mill, spray bars 195 are arranged at the level of the upper and lower work rolls 120-1, 120-2 for applying coolant and lubricant to the work rolls.

Associated with the roll stand 100 is a thickness control loop 150, a rolling force control loop 160, a position control loop 170 and / or a flatness control loop 180.

Furthermore, the mill stand 100 is associated with a lubrication and coolant circuit, which comprises means for collecting the running of the rollers coolant or lubricant, for filtering the used coolant and lubricant and for returning the cleaned coolant or lubricant to in particular the work rolls. The recirculation is typically carried out with a circulating system 192. The cleaning or filtering of the coolant and / or lubricant is typically carried out in a very fine filter 194. According to the invention, however, this prefilter is additionally preceded by a prefilter 190, for Filter out of baubles from the coolant or lubricant, as obtained during the rolling of rolling stock. This pre-filter 190 can, as shown in FIG. 1, be arranged either in front of or behind a circulation system 192; in any case, it is arranged in the flow direction before the micro-filter 194.

As an alternative to the just described circulation of the lubricant, it is also possible to carry out minimum quantity lubrication, in which only so much lubricant is applied to the rolling stock and / or to the work rolls on the inlet side, as is actually consumed or required during rolling in the roll gap.

The drive of the work rolls 120-1, 120-2 is effected by at least one drive device 124, 124-1, 124-2 with the interposition of a torque transmission device 120 ', 120 ".

In a first embodiment, as shown in Fig. 1, the torque transmitting device 120 'has an upper coupling device 126-1, an upper drive spindle 122-1 and optionally an upper transmission gear for transmitting torque from the upper drive device 124-1 the upper work roll 120-1. In this case, the upper drive spindle 122-1 between the upper work roll and the upper drive means 124-1 and the optional transmission gear 129-1 between the upper drive spindle and the upper drive means is arranged. The upper coupling device 126-1 may be disposed between the upper work roll and the upper drive spindle and / or between the upper drive spindle and the upper transmission gear and / or between the upper transmission gear and the upper drive means, and / or is in the neutral position of the upper transmission gear educated. Further, the torque transmission device 120 'according to its first embodiment has a lower clutch device 126-2, a lower drive shaft 122-2, and optionally a lower transmission gear 129-2 for transmitting torque from the lower drive device 124-2 to the lower work roll 120-2 , In this case, the lower drive spindle 122-2 between the lower work roll and the lower drive means 124-2 and the optional lower transmission gear 129-2 between the lower drive spindle and the lower drive means is arranged. The lower coupling means 126-2 may be disposed between the lower work roll and the lower drive spindle and / or between the lower drive spindle and the lower transmission gear and / or between the lower transmission gear and the lower drive means, and / or is in the neutral position of the lower transmission gear educated.

In Figure 1, the upper coupling device is shown by way of example in an open, that is uncoupled state, while the lower coupling device is shown in the closed, that is coupled state.

The torque flow from the drive means 124, 124-1, 124-2 to the work rolls can be selectively interrupted by means of the coupling means. Possible are positive, frictional, magnetic or fluid-dynamic action principles in the coupling device. The actuation of the switchable coupling device can be mechanical, electrical, electromagnetic, pneumatic or in any other construction. The arrangement of the switchable coupling device can take place on or in the comb-rolling gear, within the spindle, or on the roll neck.

The four-roll mill 100 shown in Figure 1 may be operated in a skin pass mode; the associated configuration of the roll stand 100 is illustrated schematically in FIG. The two support rollers 1 10-1, 1 10-2 are not driven in the tempering. FIG. 1 also shows upper bending cylinders 140, which act on the drive side AS and on the operating side BS on the upper work roll 120-1. When rolling is in the nip 128 and the two bending cylinders 140 each apply half a bending force F / 2 to the upper work roll 120-1, this action of the bending force causes a negative bending of the upper work roll.

In the tempering operation, first the upper support roll 1 10-1 is lifted off the upper work roll 120-1. This has the advantage that the force acting on the rolling stock in the nip 128 rolling force, as far as it is determined by the weight of the overlying rolls, is significantly lower with lifted upper support roller than if the upper support roller would rest on the upper work roll and thus on the rolling stock , The significantly lower rolling force in the tempering operation compared to a reduction operation is expressly desired in the temper rolling operation, because in the casting operation it is not the thickness reduction but only the imparting of a surface roughness structure predetermined by the work rolls in the form of temper rolling on the surface of the rolling stock.

In addition to the weight of the upper work roll 120-1, the rolling force applied to the rolling stock in the temper rolling operation is additionally defined by the bending force additionally applied by the two bending cylinders 140 on the operating side BS and the drive side AS of the rolling stand. With the help of the bending cylinder, it is possible to define an operating point for the total rolling force acting on the rolling stock and, if desired, to keep this rolling force constant at a predetermined constant rolling force setpoint with the aid of the associated rolling force control loop 160. If the bending cylinders 140 are used in this way for the precise adjustment of the rolling force, this is also referred to as an extended bending system. A particular feature of the temper rolling operation according to the invention is furthermore that none of the two support rolls 1 10-1, 1 10-2 and also only one of the two work rolls 120-1, 120-2 is driven. In Figure 1, this is exemplified by the lower work roll 120-2. It is coupled via the closed lower coupling device 126-2 and the lower drive shaft 122-2 and optionally via the transmission gear 129-2 to the lower drive means 124-2, while the upper work roll 120-2 via the opened upper coupling device 126-1 of the associated upper drive means 124-1 is decoupled.

As already mentioned, the thickness reduction of the rolling stock is significantly lower in the temper rolling operation than in a reducing operation. Nevertheless, a thickness control can also take place during a tempering operation; it is then typically referred to as a skin level control and performed by means of a skin pass control loop 150. The tempering control loop controls the thickness decrease of the rolling stock during the tempering to a predetermined constant target thickness by suitable variation of the strip tension of the rolling stock or by suitable variation of the rolling speed. The strip tension or the rolling speed serve as manipulated variables in the case of the skin pass control.

Alternatively or in addition to the above-described rolling force control loop, a position control loop 170 may be associated with the rolling stand for keeping the setting position of the work rolls constant. This can be detected metrologically either directly or indirectly by evaluating the positions of the bending cylinder 140 and be controlled via the bending cylinder as actuators. Both the control of the rolling force as well as the regulation of the position of the work rolls are preferably carried out in real time. For this purpose, the corresponding control circuits must be correspondingly fast; Preferably, their step responses are shorter than 80 ms. In addition, a flatness control loop 180 may be associated with the rolling stand for controlling the flatness of the rolling stock. The flatness control loop 180 comprises a measuring element 197, for example a flatness measuring roller for detecting the rolling stock at the outlet of the rolling stand for detecting the actual flatness of the rolling stock there. This measured actual flatness of the rolling stock is compared by subtraction compared to a predetermined desired flatness and the difference in the flatness resulting deviation is evaluated by a planarity, which in accordance with the flatness control deviation, a control signal to the actuators, eg the upper negative acting bending cylinder 140, outputs to control the flatness of the specified target flatness.

In the tempering operation only a minimal amount of lubricant is used. That is, it is used only as much lubricant as is actually consumed or needed in the nip; Ideally, especially during the tempering operation, no lubricant runs off the side of the rolling stock and ideally no lubricant remains on the rolling stock after passing through the rolling gap. The rolling stand is designed for either cold rolling of ferrous metal strip or non-ferrous metal strip. When cold rolling non-ferrous metal strip so-called rolling oil or a water-oil mixture is used as a cooling lubricant. The rolling stand is designed as a combination rolling stand, which can be operated either in a Reduzierbetriebsmodus or in a skin pass mode.

FIG. 2, in contrast to FIG. 1, shows a six-high rolling stand. This differs from the four-roll mill shown in Figure 1 by an upper intermediate roll 130-1, which between the upper work roll and the upper backup roll, and a lower intermediate roll 130-2 disposed between the lower work roll and the lower backup roll. FIG. 2 shows the operation of this six-high rolling stand in the temper rolling mode in which the upper back-up roll 1 10-1 is lifted from the upper intermediate roll 130-1. The upper bending cylinders 140 now act not on the upper work roll 120-1, but on the upper intermediate roll 130-1. Otherwise, the structure of the roll stand and the operation or mode of operation of the roll stand in the temper rolling correspond to the information described above with reference to FIG.

Figure 2 shows a second embodiment of the torque transmitting device 120 ". According to this second embodiment, the torque transmitting device 120" includes, in addition to the coupling device 126, upper and lower drive spindles 122-1, 122-2 and a comb-type gear 129 for transmitting torque from the single drive device 124 on at least one of the work rolls 120-1, 120-2. The comb-roller transmission is connected at its torque input to the single drive device 124. The upper drive spindle 122-1 is between the upper work roll and the upper torque output of the comb-type roller gear, the lower drive spindle 122-2 is between the lower work roll and the lower torque output of the comb-rolling gear, and the comb-type gear 129 is between the upper and lower drive screws and the drive means 124 arranged. The coupling device 126 may be disposed between the upper work roll and the upper drive spindle and / or between the upper drive spindle and the comb-roll transmission and / or between the lower work roll and the lower drive spindle and / or between the lower drive spindle and the comb-roll transmission or is in the idle position formed of Kammwalzgetriebes. The torque transmission device 120 'according to its first embodiment can be operated not only, as shown in Fig. 1, in conjunction with a four-roll stand, but also in conjunction with a six-high stand. The torque transmission device 120 "according to its second embodiment can be operated not only, as shown in Fig. 2, in conjunction with a six-high stand, but also in conjunction with a four-roll stand.

In both embodiments of the torque transmission device 120 ', 120 ", the coupling devices are assigned a control device 127. The control device makes it possible to open or close the coupling devices depending on the operation of the rolling stand either in the operating mode reducing operation or in the operation mode temper rolling operation for selecting either the reduce mode or the skin pass mode in a combi mill, which may alternatively run both modes of operation.

When selecting the reduction mode, the framework parameters are first set to reduction mode. This means, in particular, that the technological control loops, such as the thickness control loop, are essential for the rolling force and position detection of the jobs, as well as the flatness control loop, for which the available actuators are essential, are parameterized accordingly. The technological control loops are activated both in skin pass mode and in reduction mode, but possibly parameterized differently.

In the reducing mode, the thickness control typically takes the form of a monitor or mass flow control. All rollers are integrated in the power flow. The adjustment of the rolling force and the position of the work rolls takes place in Reduzierbetrieb on the Anstellzylinder on the top of the upper intermediate roll or the upper work roll resting support roller act. If intermediate rolls are present, they are in contact with the work rolls. Accordingly, these adjusting cylinders are to be addressed in reducing operation as actuators in said control circuits.

In the reduction mode, both work rolls are rotationally driven by the torque transfer device 120 ', 120 "from the at least one drive device 124, 124-1, 124 - 2. As work rolls, smooth-surfaced rolls are typically selected in the reduce mode essentially ready for rolling.

Alternatively, if the pultrusion mode is selected, one of the two work rolls within the torque transfer device 120 ', 120' is uncoupled from the drive means by means of the coupler while the other work roll remains coupled. Subsequently, it is then checked whether the expected rolling force in the tempering operation is greater than a predetermined rolling force threshold F_ _Gr enz or not. If this is not the case, the upper support roller is lifted from the upper work roll or from the upper intermediate roll.

The rolling force and the position control loop are configured so that the upper bending cylinder 140 are actuated as actuators. Thickness control in skin pass mode is typically done as a skin level control. If the rolling force to be set in the temper rolling operation is greater than the predetermined threshold value, the upper backup roll is placed on the upper work roll or the upper intermediate roll. Finally, all framework parameters, in particular all setpoint values for the control circuits activated in the skin pass mode, are set to suitable nominal values in Dressing operation set. Inn skimming operation, the scaffolding parameters are set in order to ensure the concrete penetration of the bending systems and the scaffold stiffness parameters required for the thickness control.

These parameters differ considerably, depending on the selected operating mode, but also in the selected application of the upper support roller.

As work rolls, special temper rolling rolls with a predetermined surface roughness are typically used in the temper rolling operation. In the tempering operation, a minimum quantity lubrication or alternatively a lubricant circuit with the prefilter 190 may be provided in order to filter out the abrasion (tinsel) in the tempering operation from the lubricant and thus to relieve the main filter. After performing the said steps, the rolling stand is then ready for rolling in the temper rolling operation. The combination rolling mill according to the invention is designed to be converted from the Reduzierkonfiguration in the temperament configuration and vice versa. Specifically, in particular, the upper back-up roll may optionally be placed on and off the upper work roll, the upper and lower work rolls may be uncoupled and uncoupled to the drive means and the smooth reduction work rolls must be against the roughened skin-pass mill rolls be exchangeable. Optionally, the pre-filter for filtering baubles in the skin pass mode can also be removable when changing over to reduction operation, since this prefilter is typically dispensable in the reduction mode.

LIST OF REFERENCE NUMBERS

100 rolling stand

1 10-1 upper backup roller

1 10-1 lower support roller

120 'Torque transmission device according to FIG. 1. embodiment

120 "torque transmission device according to the second embodiment

120-1 upper work roll

120-2 lower work roll

122-1 upper drive spindle for upper work roll

122-2 lower drive spindle for lower work roll

124 (only) drive device for combed roller gear

124-1 upper drive device for upper work roll

124-2 Lower drive device for lower work roll

126 Coupling device when using combed roller gear

126-1 upper coupling device

126-2 lower coupling device

127 control device

128 roll gap

129 comb-driven gearbox

129-1 upper gearbox

129- 2 lower transmission gear

130- 1 upper intermediate roller

130-2 lower intermediate roller

140 bending cylinder

150 thickness control loop

160 rolling force control loop

170 position loop

180 flatness control loop

190 pre-filters

192 circulation system 194 micro filters

195 spray bar 197 measuring element 200 rolling stock

AS drive side

BS operating side

F bending force

Claims

claims:

1 . Method for operating a roll stand (100) for cold rolling of

Rolling stock (200),

wherein the rolling stand comprises at least an upper and a lower support roll (10-1, 10-2) and an upper and a lower work roll (120-1, 120-2), which form a roll gap (128), and optionally also a upper and lower intermediate rolls (130-1, 130-2), and

wherein the rolling stand optionally in a mode of operation Reduzierbetrieb for reducing the thickness of the rolling stock (200) or in a

Operating mode can be operated skin pass mode;

characterized,

in that the upper or the lower work roll (120-1, 120-2) is uncoupled from its drive device (124, 124-1, 124-2) in the temper rolling operation.

2. The method according to claim 1, characterized

that for the tempering operation, the upper back-up roll (1 10-1) from the upper work roll (120-1) or, if present, from the upper

Intermediate roller (130-1) is lifted; and

the application and adjustment of a rolling force (F) is effected by the action of upper bending cylinders (140) on the upper working roll (120-1) or, if present, on the upper intermediate roll (130-1).

3. The method according to claim 2, characterized

in that the thickness of the rolling stock (200) is controlled to a predetermined constant nominal thickness by means of a skin pass control loop (150) by suitable variation of the strip tension of the rolling stock or the rolling speed as manipulated variables.

4. The method according to claim 3, characterized

that of the bending cylinders (140) applied to the rolling stock (200) Bending force (F) by means of a rolling force control loop (160) and / or preferably also the setting position of the work rolls (120-1, 120-2) by means of a position control loop (170) is kept constant.

5. The method according to any one of claims 2 to 4, characterized in that the flatness of the rolling stock by means of a flatness control loop (180) is controlled by measuring the actual flatness at the output of the

Roll stand and suitable action on actuators in accordance with a flatness control deviation as the difference between a predetermined desired flatness and the measured actual flatness.

6. The method according to any one of the preceding claims, characterized

in

that the lubricant is prefiltered after use and before reuse.

7. The method according to any one of the preceding claims

characterized,

that only a minimal amount of pure lubricant is used in the temper rolling operation.

8. The method according to any one of the preceding claims, characterized

in that the rolling stock (200) is um

Non-ferrous metal strip or ferrous metal strip.

9. The method according to claim 8,

characterized,

that rolling oil is used as lubricant during the casting of non-ferrous metal strip as rolling stock.

10.Verfahren according to any one of the preceding claims, characterized

in temper rolling, temper rolling with a surface roughening is used as working rolls (120-1, 1202); and

in that preferably the temper rolling rollers are cleaned in the breaks of the tempering operation by high-pressure spraying with the lubricant and / or with the aid of brushes.

1 1. Rolling stand (100) for cold rolling of rolling stock, comprising:

an upper and a lower support roller (1 10-1, 1 10-2);

upper and lower work rolls (120-1, 120-2) supported between the back-up rolls and defining a nip (128); optionally also an upper and lower intermediate roll (130-1, 130-2), which are mounted between the working and support rollers;

at least one drive means (124, 124-1, 124-2) for driving the work rolls; and

a torque transmitting device (120 ', 120 ") for transmitting a torque from the at least one drive device to the work rolls,

wherein the rolling stand is designed as a combined reducing and tempering with the alternative operating modes reducing mode for reducing the thickness of the rolling stock or skin pass mill;

characterized,

in that the torque transmission device (120 ', 120 ") has at least one coupling device (126, 126-1, 126-2) and an associated control device (127) for uncoupling the upper or lower work roll from the at least one drive device (124, 124). 1, 124-2) during the tempering operation.

12. rolling stand (100) according to claim 1 1, characterized,

that

the drive means is provided in the form of upper drive means (124-1) for driving the upper work roll; and

the torque transmission device (120 ') comprises the coupling device in the form of an upper coupling device (126-1), an upper one

Drive spindle (122-1) and optionally an upper gear transmission (129-1) for transmitting a torque from the upper drive means (124-1) on the upper work roll (120-1),

wherein the upper drive spindle (122-1) between the upper work roll and the upper drive means (124-1) and the optional

Translation gear (129-1) is arranged between the upper drive spindle and the upper drive means; and

wherein the upper coupling means (126-1) between the upper

Work roller and the upper drive spindle and / or between the upper drive spindle and the upper transmission gear and / or between the upper transmission gear and the upper drive means is arranged and / or as an idle position of the upper

Transmission gear (129-1) is formed.

13. rolling stand (100) according to claim 12,

characterized in that

the drive means includes, in addition to the upper drive means (124-1), lower drive means (124-2) for driving the lower work roll (120-2); and

the torque transmission device (120 ') further comprises a lower coupling device (126-1), a lower drive spindle (122-2) and optionally a lower transmission gear (129-2) for

Transmitting a torque from the lower drive means (124-2) to the lower work roll (120-2), wherein the lower drive spindle (122-2) between the lower

Work Roller and the lower drive means (124-2) and the optional lower transmission gear (129-2) between the lower drive spindle and the lower drive means is arranged; and

wherein the lower coupling means (126-2) is disposed between the lower work roll and the lower drive spindle and / or between the lower drive spindle and the lower translation gear (129-2) and / or between the lower gear transmission and the lower drive means (124-2) is and / or is designed as an idle position of the lower transmission gear.

14. rolling stand according to claim 1 1,

characterized in that

the torque transmission device (120 ") next to

Coupling device (126) has an upper and a lower drive spindle (122-1, 122-2) and a comb roller gearbox (129) for transmitting a torque from the drive device (124) to at least one of the work rolls (120-1, 120-2) .

wherein the combing gear is connected at its torque input to the single drive means (124);

wherein the upper drive spindle (122-1) between the upper work roll and the upper torque output of the comb-rolling gear, the lower drive spindle (122-2) between the lower work roll and the lower torque output of the Kammwalzgetriebes and

Combing gear between the drive spindles (122-1, 122-2) and the drive means (124) is arranged; and

wherein the coupling means (126) between the upper work roll and the upper drive spindle and / or between the upper

Drive spindle and the upper torque output of

Kammwalzgetriebes and / or between the lower work roll and the lower drive spindle and / or between the lower drive spindle and the lower torque output of Kammwalzgetriebes is arranged and / or is designed as an idle position of Kammwalzgetriebes.

15. rolling stand (100) according to any one of claims 1 1 to 14, characterized by

at least upper bending cylinders (140) for applying and setting a rolling force (F) in the nip (128) by acting on the upper

Work roll (120-1) or - if present - on the upper intermediate roll (130-1).

16. rolling stand (100) according to any one of claims 1 1 to 15,

characterized,

in that the roll stand (100) has a skin pass control loop (150) for controlling the thickness of the rolling stock in the skin pass mode, a rolling force control loop (160) for keeping the rolling force constant during the skin pass, a position control loop (170) and / or a

Flatness control loop (180) for ensuring the flatness of the rolling stock.

17. rolling stand (100) according to any one of claims 1 1 to 16,

characterized,

in that the rolling stand (100) is designed to be operated in accordance with the method according to one of claims 1 to 10.

18. rolling stand (100) according to any one of claims 1 1 -17,

marked by

a spray bar (195) for rolling oil in the inlet of the roll stand for the casting of non-ferrous metal strip as a rolling stock.