EP4005695A1 - Set of tensioning rollers for straightening a strip, straightening plant, skinpass frame assembly and method for operating a straightening plant - Google Patents

Abstract

Tension roller set (3, 4) for a straightening system (1) for straightening a strip (2) or for a re-rolling stand for re-rolling a strip, the tension roller set (3, 4)• a first tension roller (8) with a first roller axis and• at least has a second tensioning roller (9) with a second roller axis, the first tensioning roller (8) being a flatness measuring roller which has a force sensor for measuring a radial force exerted on the circumferential surface of the flatness measuring roller, and a drive for the second tensioning roller (9) being provided, with which a torque about the second roller axis can be applied to the second tensioning roller (9), whereby• either the first tensioning roller (8) is designed without a drive• or an auxiliary drive is provided for the first tensioning roller, with which a torque about the first roller axis can be applied to the first tensioning roller, the auxiliary drive for the first tensioning roller being weaker than the drive for the second tensioning roller.

Description

The invention relates to a set of tension rollers for a straightening system for straightening a strip. Furthermore, the invention relates to a straightening system for straightening a strip. Furthermore, the invention relates to a re-rolling mill for re-rolling a strip. Furthermore, the invention relates to a method for operating a straightening system or a re-rolling stand system.

Increasingly higher demands are being placed on the quality of products and semi-finished products made from sheet metal and strip material. The various customers require sheet metal products that are subject to very narrow tolerances for optical and process-related reasons. An essential quality feature of sheet metal products is their flatness. Due to various influences, this flatness requirement is very often not met during rolling. Strip straightening methods are therefore subsequently used to eliminate the unflatness. Length compensation is achieved by plastic stretching of the shorter parts of the ligament in the ligament. In this way, for example, center or edge waves can be eliminated. The strip sections, which were of different lengths before the straightening process and were therefore sometimes wavy, are lengthened differently plastically.

• einen Einlauf-Spannrollensatz, in dem der Bandzug gegenüber dem Bandzug in der Linie erhöht wird,
• eine Reckzone oder ein Streckbiegegerüst und
• einen Auslauf-Spannrollensatz, in dem der Bandzug wieder auf das Niveau der Linie reduziert wird,

aufweisen.For straightening strips, continuous straightening methods are regularly used, which are divided into stretch bending straightening, stretch straightening or a combined stretch bending and stretch bending straightening with regard to their mode of action. What all three have in common is that they

• an infeed idler set in which the strip tension is increased compared to the strip tension in the line,
• a stretching zone or stretch bending stand and
• an outlet tension roller set, in which the strip tension is reduced back to the level of the line,

exhibit.

In order for the stretching zone and/or the bending frame to be optimally adjusted, it is necessary to continuously measure the flatness of the strip.

In the stretching zone, or before or after the bending frame, there are usually very cramped installation conditions. Also, cramped installation conditions are prevalent between the exit tension roller set and, for example, a take-up reel.

Out of EP 1 789 211 B1 a strip treatment system with a pair of tensioning rollers is known, in which the strip is guided over a tensioning roller of the pair of tensioning rollers and the tension on the strip is increased or decreased by the tensioning roller between the inlet to the tensioning roller and the outlet from the tensioning roller, with the tensioning roller having at least one on its circumference measuring sensor arranged on the tension roller for detecting the tension distribution in the belt.

From the DE 10 2018 111 627 A1 discloses a stretch-bending-straightening system with a feed means for feeding a strip-shaped material along a running direction into a high-drawing area and a low-drawing area, the low-drawing area being downstream of the high-drawing area in the moving direction. In the known stretch-bending-straightening system, a bending-straightening unit is provided, which is arranged in the high-tension area. Furthermore, at least one measuring system for determining a first measured value in the high-tension area is known. Provision is made for at least one additional measuring system to be provided for determining a second measured value in the pull-down area.

Against this background, the invention was based on the object of proposing a set of tension rollers for a leveling system for leveling a strip or for a re-rolling stand system for re-rolling a strip, which when used in a leveling system allows the strip to be leveled or re-rolled better when it is used in a re-rolling stand system can be.

This object is achieved by the set of tensioning rollers according to claim 1, by the straightening system according to claim 8, by the re-rolling stand system according to claim 10 and by the method according to claim 11, 12 or 13. Advantageous embodiments are provided in the subclaims and the description below.

The invention is based on the basic idea that a tensioning roller of the tensioning roller set, as in EP 1 789 211 B1 proposed to be in the form of a flatness measuring roller, with the tensioning roller set being developed further according to the invention such that a drive is provided for the second tensioning roller, with which a torque about the second roller axis can be applied to the second tensioning roller, but according to the invention the first tensioning roller is either designed without a drive or an auxiliary drive is provided for the first tensioning roller, with which a torque about the first roller axis can be applied to the first tensioning roller, but this auxiliary drive for the first tensioning roller is designed to be weaker than the drive for the second tensioning roller.

It has been shown that in the case of tensioning rollers that are provided with drives, the drive often supplies the required torque on one side via the bearing journal of the tensioning roller. When the belt is pulled, the torque applied to the tension roller via the drive counteracts the belt retraction, with the result that the roller body of the tension roller and any coating material present are deformed or twisted in the elastic range. Such a deformation of the roller body of the tensioning roller and the possibly present coating material can falsify the measurement of the force sensor.

By now, according to the invention, the first tensioning roller, which is designed as a flatness measuring roller, is either designed without a drive or is only equipped with a weaker auxiliary drive, this measurement error can be avoided or reduced. As a result, when such a set of tensioning rollers is used in a straightening system, the strip can be straightened better, since the measurement results of the flatness measuring roller are better. Likewise, when such a set of tension rollers is used in a re-rolling stand, the re-rolling of the strip can be carried out better, since the measurement results of the flatness measuring roller are better.

The invention relates to a set of tension rollers for a straightening system for straightening a strip. It is to be expected that the advantages of the invention will already be achieved with a set of rollers which has only a first tensioning roller and a second tensioning roller. According to the invention, however, the tensioning roller set preferably has a first tensioning roller, a second tensioning roller and a third tensioning roller, particularly preferably a fourth tensioning roller and even more preferably a fifth tensioning roller and very particularly preferably a sixth tensioning roller.

as well as in EP 1 789 221 B1 proposed, the first tensioning roller is a flatness measuring roller which has a force sensor for measuring a radial force exerted on the peripheral surface of the flatness measuring roller.

Embodiments are conceivable in which the set of tensioning rollers has a plurality of flatness measuring rollers, as is the case, for example, in DE 10 2019 006 788 is described. In a preferred embodiment, however, the set of tensioning rollers has only a single flatness measuring roller. This limitation to a single flatness measuring roller within the set of tension rollers means that the effort required for the set of tension rollers can be reduced.

The flatness measuring roller can be configured according to the in DE 42 36 657 A1 described measuring roller or according to the type in DE 196 16 980 A1 described measuring roller or according to the type in DE 102 07 501 C1 described measuring roller or according to the type in DE 20 2007 001 066 U1 described measuring roller or according to the type in EP 1 469 955 B1 be executed described measuring roller. Furthermore, the measuring roller according to the in WO2020/120328 A1 or by type of in WO2020/120329 A1 be executed described measuring roller.

The measuring roller has a measuring roller body. The measuring roller body preferably has a closed peripheral surface. In a preferred embodiment, the metering roller body is a solid roller extending along a longitudinal axis. A full roller is understood to mean a measuring roller body that is in one piece and whose shape was produced either with a primary shaping process, for example casting, and/or whose geometric shape was produced by a cutting process, in particular by machining, in particular by turning, drilling, milling or grinding from a one-piece semi-finished product will be produced. In a preferred embodiment, with such a measuring roller body designed as a full roller, the measuring roller pins arranged on the front side of the measuring roller for the rotatable mounting of the measuring roller, for example in ball bearings, are also part of the one-piece body. However, there are also designs such as, for example 2 the DE 20 2014 006 820 U1 are conceivable, in which the main part of the measuring roller body is designed as a cylindrical full roller, which has a cover arranged on the front side, on which the measuring roller pins are designed. Furthermore, the measuring roller body can, for example, like the one in 3 the DE 20 2014 006 820 U1 executed measuring roller body be formed, in which the measuring roller body is formed with molded pin and over the measuring roller body a jacket tube is pushed. In a particularly preferred embodiment, however, the measuring roller does not have a jacket tube, but is designed as a solid roller. Embodiments are conceivable in which the measuring roller body consists of individual disks arranged next to one another, as is the case, for example, in DE 26 30 410 C2 will be shown.

The measuring roller body of the measuring roller preferably has a closed peripheral surface. This can be achieved, for example, in that the measuring roller body is designed as a solid roller and all the recesses provided in the measuring roller body are designed in such a way that no recess leads from the recess to the peripheral surface. In such an embodiment, the recesses are particularly preferably guided axially and have an opening on one end face of the measuring roller body, or transverse channels are provided within the measuring roller body, which lead from the recess radially further into the interior of the measuring roller body, for example to a collecting channel in the center of the measuring roller body. A closed peripheral surface of the measuring roller body can also be achieved in that in embodiments in which the respective recess has a recess leading in the direction of the peripheral surface, this is closed by a closure element. Such a closure element can be a casing tube that completely surrounds a base body of the measuring roller body, as for example in FIGS 3 and 4 of the DE 10 2014 012 426 A1 shown. However, the closure element can also be in the manner of in DE 197 47 655 A1 be formed cover shown. In a preferred embodiment, however, the measuring roller does not have a jacket tube, but is designed as a solid roller, either as such in which no recess leads from the recess to the peripheral surface, or as such in which the respective recess has a recess leading in the direction of the peripheral surface is, but which is closed by a closure element, such as a cover. In addition, coatings, for example the peripheral surface of a solid roller or the peripheral surface of a casing tube, are conceivable, for example to reduce friction or to protect the strip-shaped material to be guided over the measuring roller.

At least one recess is provided in the measuring roller body of the measuring roller. It has been shown that the advantages of the invention can already be achieved with a single recess in the measuring roller body. It is thus conceivable in the case of the flatness measurement to provide information about the flatness of the strip-shaped material guided over the measuring roller once per revolution of the measuring roller.

In a preferred embodiment, the measuring roller body has a plurality of recesses. In a preferred embodiment, the recesses are designed at the same radial distance from the longitudinal axis of the measuring roller body. In a preferred embodiment, all of the recesses are distributed equidistantly from one another in the circumferential direction. However, embodiments are also conceivable in which a first group of recesses is provided, which is particularly preferred are arranged at the same radial distance from the longitudinal axis and equidistantly distributed in the circumferential direction, and in which, in addition to this first group of recesses, at least one further recess is provided which is designed differently in terms of its radial distance from the longitudinal axis than the recesses of the first group and /or does not have the same distance in the circumferential direction from the other recesses as the other recesses have from one another. For example, it is conceivable to design a measuring roller with regard to the flatness measurement like a measuring roller of the prior art, for example like that from FIG DE 102 07 501 known full role or the off DE 10 2014 012 426 A1 known measuring rollers, but then to provide these measuring rollers of the prior art with a further recess outside the grid for further equipment, with which a different measurement is carried out, for example. The recesses mentioned in this paragraph are preferably those that run in the axial direction of the measuring roller body. Embodiments are also conceivable in which the measuring roller has a single recess and all the force sensors of the measuring roller are arranged in a single recess, for example in a single axially running recess.

In a preferred embodiment, the measuring roller body has a closed peripheral surface and is closed off at each end by an end face. In a preferred embodiment, the end faces are arranged at an angle of 90° to the peripheral surface.

In a preferred embodiment, the measuring roller has bearing journals. In a preferred embodiment, in embodiments of the measuring roller with end faces, the bearing journals are formed on the end faces.

In a preferred embodiment, the measuring roller body is cylindrical.

In a preferred embodiment, the measuring roller is designed with at least one recess in the measuring roller body, which is arranged at a distance from the peripheral surface, the recess not opening towards the peripheral surface, or no further recess continuing from the recess, for example no bore leading to the peripheral surface . In an alternative preferred embodiment, the recess leads from the peripheral surface into the interior of the measuring roller body, but is closed by a closure element. In a preferred embodiment, in the embodiments in which the measuring roller is designed with a plurality of recesses in the measuring roller body, which are arranged at a distance from the peripheral surfaces, either all recesses are designed in such a way that no recess, e.g. no bore of the recess leads to the peripheral surface (nor does the recess itself open into the peripheral surface), or some recesses are designed in such a way that no recess leads from the respective recess to the peripheral surface, while other recesses have a recess leading in the direction of the peripheral surface , but which is closed by a closure element. As stated above, the closure element is a cover or, for example, a jacket tube.

In a preferred embodiment, a recess in the measuring roller body extends in a direction parallel to the longitudinal axis of the measuring roller body. If, according to a preferred embodiment, several recesses are provided in the measuring roller body, it is preferred that all recesses of the measuring roller body each extend in a direction parallel to the longitudinal axis of the measuring roller body. In a preferred embodiment, the respective recess opens out at least at one of its ends, preferably at both of its ends, on an end face of the measuring roller body. A recess ending on an end face of a measuring roller body can be closed by an end cap, with this end cap only closing this recess. Embodiments are also conceivable in which the end face of the measuring roller body is completely closed by a cover, as for example in 1 and 2 , or Fig. 4 of the DE 10 2014 012 426 A1 shown.

In a preferred embodiment, the recess is elongate, "elongate" meaning that the recess is larger in a first direction (in the longitudinal direction of the recess) than in any direction perpendicular to this direction. In a preferred embodiment, the extent of the elongate recess in the longitudinal direction is twice, or more preferably more than twice, greater than in any direction perpendicular to that direction. In a preferred embodiment, the longitudinal direction of the recess encloses an angle with the longitudinal direction of the measuring roller body that is less than 75°, particularly preferably <45°, particularly preferably <30°, particularly preferably <10°, particularly preferably <5°. In a preferred embodiment, the longitudinal direction of the recess is not perpendicular to the longitudinal axis of the measuring roller body. If - which would be conceivable in one embodiment - the longitudinal axis of the recess and the longitudinal axis of the measuring roller body do not intersect, the above-mentioned design rule applies to the projection of the longitudinal axis of the recess onto the plane that contains the longitudinal axis of the measuring roller body. In these embodiments, the projection of the longitudinal axis of the recess onto a plane containing the longitudinal axis of the measuring roller body is designed in such a way that the projection of the longitudinal direction of the recess coincides with the longitudinal direction of the measuring roller body encloses an angle which is less than 75°, particularly preferably <45°, particularly preferably <30°, particularly preferably <10°, particularly preferably <5°. In the preferred embodiments in which the recess extends parallel to the longitudinal axis of the measuring roller body, the longitudinal axis of the recess obviously does not intersect the longitudinal axis of the measuring roller body, nor does a projection of the longitudinal axis onto a plane containing the longitudinal axis of the measuring roller body intersect the longitudinal axis of the measuring roller body does not cut. In DE 20 2007 001 066 U1 a measuring roller with elongated recesses is shown, for example.

In a preferred embodiment, the flatness measuring roller has an axial bore running parallel to the first roller axis, with the force sensor being arranged in the axial bore. According to the invention, the flatness measuring roller is no longer influenced by torsional forces, or only to a small extent. This also role versions can be used in which the sensors are not only in radial bores, but also in axial bores, such as in the EP 1 469 955 A1 described, are used.

In a preferred embodiment, the flatness measuring roller has a surface coating. The flatness measuring roller particularly preferably has a coating of tungsten carbide or chromium. The surface coating can also be implemented as a rubber or polyurethane coating.

In this description, reference is made to a first tensioning roller and a second tensioning roller and, in the context of preferred embodiments, to a third tensioning roller, a fourth tensioning roller and sometimes even to a fifth and a sixth tensioning roller of a tensioning roller set. The use of the ordinal numbers "first", "second", "third", "fourth", "fifth" and "sixth" does not necessarily mean, but only in a preferred embodiment, that the belt running through the tensioning roller set via the existing tensioning rollers in the Order of their ordinal numbers is performed, i.e. it is first guided over the first tension roller and then over the second tension roller, etc. The invention is initially based on the finding that within a set of tensioning rollers there is a tensioning roller with a drive (the so-called "second tensioning roller") and, in addition, a flatness measuring roller referred to as the "first tensioning roller", which has no drive or is equipped with an auxiliary drive. First of all, the invention does not specify the spatial position in which the first tensioning roller and the second tensioning roller are located in relation to one another. It is not absolutely necessary for achieving the advantages of the invention that the flatness measuring roller (the "first idler") is the spatially first idler over which the strip runs as the strip enters the idler set. It is for attaining the benefits of Invention also not absolutely necessary that the "second tensioning roller" is the tensioning roller that is immediately downstream of the flatness measuring roller (the "first tensioning roller") in the direction of belt travel. Embodiments are therefore also conceivable in which the flatness measuring roller (the “first tensioning roller”) is the last tensioning roller of a tensioning roller set or a tensioning roller arranged between the foremost tensioning roller and the last tensioning roller of a tensioning roller set. Embodiments are also conceivable in which further tensioning rollers, possibly driven but also possibly non-driven tensioning rollers, are provided between the flatness measuring roller (the “first tensioning roller”) and the driven, second tensioning roller.

In a preferred embodiment, however, the second tensioning roller is the tensioning roller of the set of tensioning rollers, over which the belt is guided after it leaves the first tensioning roller, which is designed as a flatness measuring roller. In a very particularly preferred embodiment, the first tensioning roller designed as a flatness measuring roller is the tensioning roller of the set of tensioning rollers, onto which the strip runs first when it enters the set of tensioning rollers. In a preferred embodiment, in which a third tensioning roller is provided, this third tensioning roller is arranged downstream of the second tensioning roller in the direction of belt travel, particularly preferably immediately downstream. In a preferred embodiment, in which a fourth tensioning roller is provided, this fourth tensioning roller is arranged downstream of the third tensioning roller in the direction of belt travel, particularly preferably immediately downstream. In a preferred embodiment, in which a fifth tensioning roller is provided, this fifth tensioning roller is arranged downstream of the fourth tensioning roller in the direction of belt travel, particularly preferably immediately downstream. In a preferred embodiment, in which a sixth tensioning roller is provided, this sixth tensioning roller is arranged downstream of the fifth tensioning roller in the direction of belt travel, particularly preferably immediately downstream.

The preferred arrangement of the individual tensioning rollers described in the previous paragraph is particularly suitable for embodiments in which the set of tensioning rollers according to the invention is to be arranged after a stretching zone or after a bending frame and there is a desire to document the level of flatness with which the strip passes through the stretching zone or .leaves the bending stand. This preferred arrangement is also suitable for a set of tension rollers which is arranged downstream of a decoiler and there is a desire to document the level of flatness with which the strip leaves the coiler.

In a preferred, alternative embodiment, however, the first tensioning roller designed as a flatness measuring roller is the tensioning roller of the set of tensioning rollers, over which the strip is guided after it leaves the second tensioning roller. Here is in one In a very particularly preferred embodiment, the first tensioning roller designed as a flatness measuring roller is the tensioning roller of the set of tensioning rollers from which the strip runs last when it runs out of the set of tensioning rollers. In this preferred embodiment, the first tensioning roller, designed as a flatness measuring roller, is therefore the last tensioning roller of the set of tensioning rollers. In a preferred embodiment, in which a third tensioning roller is provided, this third tensioning roller is arranged upstream of the second tensioning roller in the direction of belt travel, particularly preferably directly upstream. In a preferred embodiment, in which a fourth tensioning roller is provided, this fourth tensioning roller is arranged upstream of the third tensioning roller in the direction of belt travel, particularly preferably directly upstream. In a preferred embodiment, in which a fifth tensioning roller is provided, this fifth tensioning roller is arranged upstream of the fourth tensioning roller in the direction of belt travel, particularly preferably directly upstream. In a preferred embodiment, in which a sixth tensioning roller is provided, this sixth tensioning roller is arranged upstream of the fifth tensioning roller in the direction of belt travel, particularly preferably immediately upstream.

The preferred arrangement of the individual tensioning rollers described in the preceding paragraph is particularly suitable for embodiments in which the tensioning roller set according to the invention is to be arranged in front of a take-up reel and there is a desire to document the level of flatness with which the strip is wound onto the take-up reel. This preferred arrangement is also suitable for a tension roller set that is to be arranged in front of a stretching zone or a bending frame and there is a desire to document the level of flatness with which the strip enters the stretching zone or the bending frame.

The invention provides a drive for the second tensioning roller, with which a torque about the second roller axis can be applied to the second tensioning roller. Such a drive is particularly preferably equipped with an electric motor and a gear with which adjustable torques can be generated. The drive applies the torque to one of the bearing journals of the tensioning roller, particularly preferably on one side. In a preferred embodiment, the drive is designed to apply a maximum torque in the range of 1-100 kNm to the tensioning roller.

In a preferred embodiment, the first tensioning roller is designed to be non-driven and all the remaining tensioning rollers that are present are designed to be driven. In a preferred embodiment, the first tensioning roller has an auxiliary drive and all other tensioning rollers that are present are also driven.

According to a first embodiment of the set of tensioning rollers according to the invention, the first tensioning roller designed as a flatness measuring roller is designed to be non-driven. In this embodiment of the tensioning roller set according to the invention, no drive is provided for the first tensioning roller, with which a torque about the first roller axis can be applied to the first tensioning roller. The first tensioning roller is therefore designed as a trailing roller.

In the alternative provided according to the invention, an auxiliary drive is provided for the first tensioning roller, with which a torque about the first roller axis can be applied to the first tensioning roller. However, this auxiliary drive for the first tensioning roller is designed to be weaker than the drive for the second tensioning roller. While the drive for the second idler is designed in such a way that it can be used, following the basic idea of an idler set, to increase or decrease the belt tension in the belt, it may be that an auxiliary drive for the first idler is necessary to during start-up of the straightener to rotate the first tensioning roller, thus enabling the threading of the strip and, if necessary, to accelerate and decelerate the roller. However, such an auxiliary drive is not necessary for the actual operation of the straightening system and, in a preferred embodiment of the method according to the invention, is switched off after a start-up phase or is regulated to a torque of 0 Nm.

In a preferred embodiment, the auxiliary drive is designed to be weaker by an order of magnitude than the drive for the second tensioning roller. In a preferred embodiment, the auxiliary drive can generate a maximum torque that is in the range of 0.03 to 0.3 kNm.

In a preferred embodiment, a third tensioning roller is provided with a third roller axis. A drive for the third tensioning roller is particularly preferably provided, with which a torque about the third roller axis can be applied to the third tensioning roller. In a preferred embodiment, the drive for the third idler can generate a maximum torque that is at least twice the maximum torque that the drive for the second idler can generate. This applies in particular to applications in which, in the sequence in which the strip runs over the tensioning rollers, the third tensioning roller is closer to a stretching zone, a bending stand or a tempering stand than the second tensioning roller. In a preferred embodiment, the drive for the third idler can generate a maximum torque that is at least half less than the maximum torque that the drive for the second idler can generate. This is especially true for the use cases where in the order in which the tape runs over the tensioning rollers, the second tensioning roller is closer to a stretching zone, a bending stand or a tempering stand than the third tensioning roller.

In a preferred embodiment, a fourth tensioning roller is provided with a fourth roller axis. A drive for the fourth tensioning roller is particularly preferably provided, with which a torque about the fourth roller axis can be applied to the fourth tensioning roller. In a preferred embodiment, the drive for the fourth idler can generate a maximum torque that is at least twice the maximum torque that the drive for the third idler can generate. This applies in particular to those applications in which, in the sequence in which the strip runs over the tensioning rollers, the fourth tensioning roller is closer to a stretching zone, a bending stand or a tempering stand than the third tensioning roller. In a preferred embodiment, the drive for the fourth idler can generate a maximum torque that is at least half less than the maximum torque that the drive for the third idler can generate. This applies in particular to those applications in which, in the sequence in which the strip runs over the tensioning rollers, the third tensioning roller is closer to a stretching zone, a bending stand or a tempering stand than the fourth tensioning roller.

In a preferred embodiment, a fifth tensioning roller is provided with a fifth roller axis. A drive for the fifth tensioning roller is particularly preferably provided, with which a torque about the fifth roller axis can be applied to the fifth tensioning roller. In a preferred embodiment, the drive for the fifth idler can produce a maximum torque that is at least twice the maximum torque that the drive for the fourth idler can produce. This is particularly true for those applications where, in the sequence in which the strip runs over the idlers, the fifth idler is closer to a stretching zone, bending stand, or temper rolling stand than the fourth idler. In a preferred embodiment, the drive for the fifth idler can produce a maximum torque that is at least half less than the maximum torque that the drive for the fourth idler can produce. This applies in particular to those applications in which, in the sequence in which the strip runs over the tensioning rollers, the fourth tensioning roller is closer to a stretching zone, a bending stand or a tempering stand than the fifth tensioning roller.

In a preferred embodiment, a sixth tensioning roller with a sixth roller axis is provided. A drive for the sixth tensioning roller is particularly preferably provided, with which a torque about the sixth roller axis can be applied to the sixth tensioning roller. In a preferred embodiment For example, the drive for the sixth idler can produce a maximum torque that is at least twice the maximum torque that the drive for the fifth idler can produce. This applies in particular to applications in which, in the sequence in which the strip runs over the tensioning rollers, the sixth tensioning roller is closer to a stretching zone, a bending stand or a tempering stand than the fifth tensioning roller. In a preferred embodiment, the drive for the sixth idler can produce a maximum torque that is at least half less than the maximum torque that the drive for the fifth idler can produce. This applies in particular to those applications in which, in the sequence in which the strip runs over the tensioning rollers, the fifth tensioning roller is closer to a stretching zone, a bending stand or a tempering stand than the sixth tensioning roller.

In a preferred embodiment, the drive for the second tensioner can apply a maximum torque T2 about the second roller axis to the second tensioner and the auxiliary drive for the first tensioner can apply a maximum torque T1 about the first roller axis to the first tensioner, where T1 is equal or less than 7/8 of T2, more preferably equal to or less than 3/4 of T2, more preferably equal to or less than half of T2, most preferably equal to or less than 1/8 of T2, whole more preferably equal to or less than 1/10 of T2.

• senkrecht zu der Horizontalen steht,
• in Auflaufrichtung nach der ersten Rollenachse der ersten Spannrolle angeordnet ist und
• tangential zur Oberfläche der ersten Spannrolle verläuft.

In a preferred embodiment, the second tensioning roller is arranged relative to the first tensioning roller in such a way that the plane which is perpendicular to the horizontal and which contains the second roller axis points in the direction of a run-up direction in which the belt is to run onto the tensioning roller set according to the invention, seen in front of the level that lies

• is perpendicular to the horizontal,
• is arranged in the direction of take-up after the first roller axis of the first tensioning roller and
• tangential to the surface of the first idler pulley.

In a preferred embodiment, the second roller axis is arranged in a horizontal plane which lies below a horizontal plane in which the first roller axis is arranged.

• die Ebene, die senkrecht zur Horizontalen steht und die die zweite Rollenachse enthält, auf einer Seite einer Ebene liegt, die senkrecht zu der Horizontalen steht und tangential zur Oberfläche der ersten Spannrolle verläuft und
• die Ebene, die senkrecht zur Horizontalen steht und die die dritte Rollenachse enthält, auf der anderen Seite der Ebene liegt, die senkrecht zu der Horizontalen steht und tangential zur Oberfläche der ersten Spannrolle verläuft.

In a preferred embodiment that includes a third idler, the second idler and the third idler are positioned relative to the first idler such that

• the plane perpendicular to the horizontal and containing the second idler axis lies on one side of a plane perpendicular to the horizontal and tangent to the surface of the first idler, and
• the plane perpendicular to the horizontal and containing the third roller axis lies on the other side of the plane perpendicular to the horizontal and tangent to the surface of the first idler roller.

In this embodiment, a fourth tensioning roller is particularly preferably additionally provided, with the fourth roller axis being particularly preferably arranged between the first roller axis and the third roller axis, viewed in the horizontal direction.

In a preferred embodiment, the first roller axis and the second roller axis are aligned parallel to one another. In a preferred embodiment, all the roller axes of the tensioning rollers of the tensioning roller set are parallel to one another. In a preferred embodiment, viewed in a horizontal direction, the second roller axis is in front of the first roller axis and the fourth roller axis after the first roller axis and the third roller axis after the fourth roller axis. In a particularly preferred embodiment, the fifth roller axis is arranged after the third roller axis. In a particularly preferred embodiment, a sixth roller axis is arranged between the fifth roller axis and the third roller axis.

In the straightening system according to the invention for straightening a strip, a front set of tension rollers and a rear set of tension rollers are provided. A stretching zone may be provided between the front idler set and the rear idler set. A bending frame can be provided between the front tension roller set and the rear tension roller set. A stretching zone and a bending frame can be provided between the front set of tension rollers and the rear set of tension rollers.

According to the invention, the front tensioning roller set can be designed as a tensioning roller set according to the invention or the rear tensioning roller set can be designed as a tensioning roller set according to the invention. Likewise, according to the invention, both the front tensioning roller set and the rear tensioning roller set can be designed as tensioning roller sets according to the invention.

In a preferred embodiment, a further flatness measuring roller is provided in front of the front tensioning roller set and/or after the front tensioning roller set and/or in front of the rear tensioning roller set and/or after the rear tensioning roller set. In a particularly preferred alternative is before the front set of idlers and / or after the front set of idlers and / or before rear set of tension rollers and/or no further flatness measuring roller provided after the rear set of tension rollers.

If the first tensioning roller designed as a flatness measuring roller is the first tensioning roller of the rear set of tensioning rollers onto which the strip runs when it leaves the stretching zone or the bending frame, the flatness of the strip can be determined immediately after leaving the stretching zone or after leaving the bending frame will. If the first tensioning roller, designed according to the invention as a flatness measuring roller, is the last tensioning roller of the front set of tensioning rollers, over which the strip runs before it leaves the front set of tensioning rollers, this arrangement allows the flatness of the strip to be checked immediately before the strip enters the stretching zone or immediately before the the strip entering the bending stand can be determined.

However, embodiments are also conceivable in which there is an interest in the flatness with which the strip enters the straightening system according to the invention or with which flatness it leaves the straightening system according to the invention. For this reason, embodiments are also expedient in which the first tensioning roller designed as a flatness measuring roller is the first tensioning roller of the front set of tensioning rollers, onto which the belt runs when it runs into the front set of tensioning rollers. In such an embodiment, the flatness of the strip as it leaves the coiler can be determined with the flatness measuring roller according to the invention. An embodiment can also be expedient in which the first tensioning roller designed as a flatness measuring roller is the last tensioning roller of the rear set of tensioning rollers, over which the strip runs before it leaves the rear set of tensioning rollers. With such an arrangement of the flatness measuring roller, the flatness of the strip can be determined before it runs onto the coiler.

• Keine = Keine Planheitsmessrolle ist an diesem Ort vorgesehen
• Eine = Eine Planheitsmessrolle ist an diesem Ort vorgesehen
  1. (1) = eine erste Spannrolle diese Spannrollensatzes ist als Planheitsmessrolle ausgeführt, die erste Spannrolle ist an einem beliebigen Platz im Spannrollensatz angeordnet
  2. (2) = eine erste Spannrolle diese Spannrollensatzes ist als Planheitsmessrolle ausgeführt, die erste Spannrolle ist die Spannrolle, auf die das Band als erstes aufläuft
  3. (3) = eine erste Spannrolle diese Spannrollensatzes ist als Planheitsmessrolle ausgeführt, die erste Spannrolle ist die letzte Spannrolle des Spannrollensatzes, von der das Band abläuft
  4. (4) = der Spannrollensatz weist zwei als Planheitsmessrollen ausgeführte Spannrollen auf

Vor vorderem Spann rollen satz Im vorderen Spannrollen satz Nach vorderem Spann rollen satz, aber vor Reckzone, bzw. vor Biegegerüst Vor hinterem Spann rollen satz, aber nach Reckzone, bzw. nach Biegegerüst Im hinteren Spannrollen satz Nach hinterem Spann rollen satz Keine Keine Keine Keine (1) Keine Keine Keine Keine Keine (2) Keine Keine Keine Keine Keine (3) Keine Keine Keine Keine Keine (4) Keine Keine Keine Keine Eine (1) Keine Keine Keine Keine Eine (2) Keine Keine Keine Keine Eine (3) Keine Keine Keine Keine Eine (4) Keine Keine Keine Keine Keine (1) Eine Keine Keine Keine Keine (2) Eine Keine Keine Keine Keine (3) Eine Keine Keine Keine Keine (4) Eine Keine Keine Keine Eine (1) Eine Keine Keine Keine Eine (2) Eine Keine Keine Keine Eine (3) Eine Keine Keine Keine Eine (4) Eine Keine (1) Keine Keine (1) Keine Keine (1) Keine Keine (2) Keine Keine (1) Keine Keine (3) Keine Keine (1) Keine Keine (4) Keine Keine (1) Keine Eine (1) Keine Keine (1) Keine Eine (2) Keine Keine (1) Keine Eine (3) Keine Keine (1) Keine Eine (4) Keine Keine (1) Keine Keine (1) Eine Keine (1) Keine Keine (2) Eine Keine (1) Keine Keine (3) Eine Keine (1) Keine Keine (4) Eine Keine (1) Keine Eine (1) Eine Keine (1) Keine Eine (2) Eine Keine (1) Keine Eine (3) Eine Keine (1) Keine Eine (4) Eine Keine (2) Keine Keine (1) Keine Keine (2) Keine Keine (2) Keine Keine (2) Keine Keine (3) Keine Keine (2) Keine Keine (4) Keine Keine (2) Keine Eine (1) Keine Keine (2) Keine Eine (2) Keine Keine (2) Keine Eine (3) Keine Keine (2) Keine Eine (4) Keine Keine (2) Keine Keine (1) Eine Keine (2) Keine Keine (2) Eine Keine (2) Keine Keine (3) Eine Keine (2) Keine Keine (4) Eine Keine (2) Keine Eine (1) Eine Keine (2) Keine Eine (2) Eine Keine (2) Keine Eine (3) Eine Keine (2) Keine Eine (4) Eine Keine (3) Keine Keine (1) Keine Keine (3) Keine Keine (2) Keine Keine (3) Keine Keine (3) Keine Keine (3) Keine Keine (4) Keine Keine (3) Keine Eine (1) Keine Keine (3) Keine Eine (2) Keine Keine (3) Keine 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Eine (3) Keine Eine Keine Keine Eine (4) Keine Eine Keine Keine Keine (1) Eine Eine Keine Keine Keine (2) Eine Eine Keine Keine Keine (3) Eine Eine Keine Keine Keine (4) Eine Eine Keine Keine Eine (1) Eine Eine Keine Keine Eine (2) Eine Eine Keine Keine Eine (3) Eine Eine Keine Keine Eine (4) Eine Eine (1) Keine Keine (1) Keine Eine (1) Keine Keine (2) Keine Eine (1) Keine Keine (3) Keine Eine (1) Keine Keine (4) Keine Eine (1) Keine Eine (1) Keine Eine (1) Keine Eine (2) Keine Eine (1) Keine Eine (3) Keine Eine (1) Keine Eine (4) Keine Eine (1) Keine Keine (1) Eine Eine (1) Keine Keine (2) Eine Eine (1) Keine Keine (3) Eine Eine (1) Keine Keine (4) Eine Eine (1) Keine Eine (1) Eine Eine (1) Keine Eine (2) Eine Eine (1) Keine Eine (3) Eine Eine (1) Keine Eine (4) Eine Eine (2) Keine Keine (1) Keine Eine (2) Keine Keine (2) Keine Eine (2) Keine Keine (3) Keine Eine (2) Keine Keine (4) Keine Eine (2) Keine Eine (1) Keine Eine (2) Keine Eine (2) Keine Eine (2) Keine Eine (3) Keine Eine (2) Keine Eine (4) Keine Eine (2) Keine Keine (1) Eine Eine (2) Keine Keine (2) Eine Eine (2) Keine Keine (3) Eine Eine (2) Keine Keine (4) Eine Eine (2) Keine Eine (1) Eine Eine (2) Keine Eine (2) Eine Eine (2) Keine Eine (3) Eine Eine (2) Keine Eine (4) Eine Eine (3) Keine Keine (1) Keine Eine (3) Keine Keine (2) Keine Eine (3) Keine Keine (3) Keine Eine (3) Keine Keine (4) Keine Eine (3) Keine Eine (1) Keine Eine (3) Keine Eine (2) Keine Eine (3) Keine Eine (3) Keine Eine (3) Keine Eine (4) Keine Eine (3) Keine Keine (1) Eine Eine (3) Keine Keine (2) Eine Eine (3) Keine Keine (3) Eine Eine (3) Keine Keine (4) Eine Eine (3) Keine Eine (1) Eine Eine (3) Keine Eine (2) Eine Eine (3) Keine Eine (3) Eine Eine (3) Keine Eine (4) Eine Eine (4) Keine Keine (1) Keine Eine (4) Keine Keine (2) Keine Eine (4) Keine Keine (3) Keine Eine (4) Keine Keine (4) Keine Eine (4) Keine Eine (1) Keine Eine (4) Keine Eine (2) Keine Eine (4) Keine Eine (3) Keine Eine (4) Keine Eine (4) Keine Eine (4) Keine Keine (1) Eine Eine (4) Keine Keine (2) Eine Eine (4) Keine Keine (3) Eine Eine (4) Keine Keine (4) Eine Eine (4) Keine Eine (1) Eine Eine (4) Keine Eine (2) Eine Eine (4) Keine Eine (3) Eine Eine (4) Keine Eine (4) Eine Keine Keine Eine Keine (1) Keine Keine Keine Eine Keine (2) Keine Keine Keine Eine Keine (3) Keine Keine Keine Eine Keine (4) Keine Keine Keine Eine Eine (1) Keine Keine Keine Eine Eine (2) Keine Keine Keine Eine Eine (3) Keine Keine Keine Eine Eine (4) Keine Keine Keine Eine Keine (1) Eine Keine Keine Eine Keine (2) Eine Keine Keine Eine Keine (3) Eine Keine Keine Eine Keine (4) Eine Keine Keine Eine Eine (1) Eine Keine Keine Eine Eine (2) Eine Keine Keine Eine Eine (3) Eine Keine Keine Eine Eine (4) Eine Keine (1) Eine Keine (1) Keine Keine (1) Eine Keine (2) Keine Keine (1) Eine Keine (3) Keine Keine (1) Eine Keine (4) Keine Keine (1) Eine Eine (1) Keine Keine (1) Eine Eine (2) Keine Keine (1) Eine Eine (3) Keine Keine (1) Eine Eine (4) Keine Keine (1) Eine Keine (1) Eine Keine (1) Eine Keine (2) Eine Keine (1) Eine Keine (3) Eine Keine (1) Eine Keine (4) Eine Keine (1) Eine Eine (1) Eine Keine (1) Eine Eine (2) Eine Keine (1) Eine Eine (3) Eine Keine (1) Eine Eine (4) Eine Keine (2) Eine Keine (1) Keine Keine (2) Eine Keine (2) Keine Keine (2) Eine Keine (3) Keine Keine (2) Eine Keine (4) Keine Keine (2) Eine Eine (1) Keine Keine (2) Eine Eine (2) Keine Keine (2) Eine Eine (3) Keine Keine (2) Eine Eine (4) Keine Keine (2) Eine Keine (1) Eine Keine (2) Eine Keine (2) Eine Keine (2) Eine Keine (3) Eine Keine (2) Eine Keine (4) Eine Keine (2) Eine Eine (1) Eine Keine (2) Eine Eine (2) Eine Keine (2) Eine Eine (3) Eine Keine (2) Eine Eine (4) Eine Keine (3) Eine Keine (1) Keine Keine (3) Eine Keine (2) Keine Keine (3) Eine Keine (3) Keine Keine (3) Eine Keine (4) Keine Keine (3) Eine Eine (1) Keine Keine (3) Eine Eine (2) Keine Keine (3) Eine Eine (3) Keine Keine (3) Eine Eine (4) Keine Keine (3) Eine Keine (1) Eine Keine (3) Eine Keine (2) Eine Keine (3) Eine Keine (3) Eine Keine (3) Eine Keine (4) Eine Keine (3) Eine Eine (1) Eine Keine (3) Eine Eine (2) Eine Keine (3) Eine Eine (3) Eine Keine (3) Eine Eine (4) Eine Keine (4) Eine Keine (1) Keine Keine (4) Eine Keine (2) Keine Keine (4) Eine Keine (3) Keine Keine (4) Eine Keine (4) Keine Keine (4) Eine Eine (1) Keine Keine (4) Eine Eine (2) Keine Keine (4) Eine Eine (3) Keine Keine (4) Eine Eine (4) Keine Keine (4) Eine Keine (1) Eine Keine (4) Eine Keine (2) Eine Keine (4) Eine Keine (3) Eine Keine (4) Eine Keine (4) Eine Keine (4) Eine Eine (1) Eine Keine (4) Eine Eine (2) Eine Keine (4) Eine Eine (3) Eine Keine (4) Eine Eine (4) Eine Eine Keine Eine Keine (1) Keine Eine Keine Eine Keine (2) Keine Eine Keine Eine Keine (3) Keine Eine Keine Eine Keine (4) Keine Eine Keine Eine Eine (1) Keine Eine Keine Eine Eine (2) Keine Eine Keine Eine Eine (3) Keine Eine Keine Eine Eine (4) Keine Eine Keine Eine Keine (1) Eine Eine Keine Eine Keine (2) Eine Eine Keine Eine Keine (3) Eine Eine Keine Eine Keine (4) Eine Eine Keine Eine Eine (1) Eine Eine Keine Eine Eine (2) Eine Eine Keine Eine Eine (3) Eine Eine Keine Eine Eine (4) Eine Eine (1) Eine Keine (1) Keine Eine (1) Eine Keine (2) Keine Eine (1) Eine Keine (3) Keine Eine (1) Eine Keine (4) Keine Eine (1) Eine Eine (1) Keine Eine (1) Eine Eine (2) Keine Eine (1) Eine Eine (3) Keine Eine (1) Eine Eine (4) Keine Eine (1) Eine Keine (1) Eine Eine (1) Eine Keine (2) Eine Eine (1) Eine Keine (3) Eine Eine (1) Eine Keine (4) Eine Eine (1) Eine Eine (1) Eine Eine (1) Eine Eine (2) Eine Eine (1) Eine Eine (3) Eine Eine (1) Eine Eine (4) Eine Eine (2) Eine Keine (1) Keine Eine (2) Eine Keine (2) Keine Eine (2) Eine Keine (3) Keine Eine (2) Eine Keine (4) Keine Eine (2) Eine Eine (1) Keine Eine (2) Eine Eine (2) Keine Eine (2) Eine Eine (3) Keine Eine (2) Eine Eine (4) Keine Eine (2) Eine Keine (1) Eine Eine (2) Eine Keine (2) Eine Eine (2) Eine Keine (3) Eine Eine (2) Eine Keine (4) Eine Eine (2) Eine Eine (1) Eine Eine (2) Eine Eine (2) Eine Eine (2) Eine Eine (3) Eine Eine (2) Eine Eine (4) Eine Eine (3) Eine Keine (1) Keine Eine (3) Eine Keine (2) Keine Eine (3) Eine Keine (3) Keine Eine (3) Eine Keine (4) Keine Eine (3) Eine Eine (1) Keine Eine (3) Eine Eine (2) Keine Eine (3) Eine Eine (3) Keine Eine (3) Eine Eine (4) Keine Eine (3) Eine Keine (1) Eine Eine (3) Eine Keine (2) Eine Eine (3) Eine Keine (3) Eine Eine (3) Eine Keine (4) Eine Eine (3) Eine Eine (1) Eine Eine (3) Eine Eine (2) Eine Eine (3) Eine Eine (3) Eine Eine (3) Eine Eine (4) Eine Eine (4) Eine Keine (1) Keine Eine (4) Eine Keine (2) Keine Eine (4) Eine Keine (3) Keine Eine (4) Eine Keine (4) Keine Eine (4) Eine Eine (1) Keine Eine (4) Eine Eine (2) Keine Eine (4) Eine Eine (3) Keine Eine (4) Eine Eine (4) Keine Eine (4) Eine Keine (1) Eine Eine (4) Eine Keine (2) Eine Eine (4) Eine Keine (3) Eine Eine (4) Eine Keine (4) Eine Eine (4) Eine Eine (1) Eine Eine (4) Eine Eine (2) Eine Eine (4) Eine Eine (3) Eine Eine (4) Eine Eine (4) Eine The invention is particularly preferably carried out according to one of the embodiments listed below:
In the table below, this means:

• None = No flatness measuring roll is provided at this location
• One = A flatness measuring roll is provided at this location
  1. (1) = a first tensioning roller of this tensioning roller set is designed as a flatness measuring roller, the first tensioning roller is arranged at any place in the tensioning roller set
  2. (2) = a first tensioning roller of this tensioning roller set is designed as a flatness measuring roller, the first tensioning roller is the tensioning roller on which the belt runs first
  3. (3) = a first tensioning roller of this tensioning roller set is designed as a flatness measuring roller, the first tensioning roller is the last tensioning roller of the tensioning roller set from which the belt runs off
  4. (4) = the tensioning roller set has two tensioning rollers designed as flatness measuring rollers

In front of the front idler set In the front idler set After the front set of tension rollers, but before the stretching zone or before the bending frame In front of the rear set of tension rollers, but after the stretching zone or after the bending frame In the rear idler set After rear idler set No No No No (1) No No No No No (2) No No No No No (3) No No No No No (4) No No No No One (1) No No No No One (2) No No No No One (3) No No No No One (4) No No No No No (1) One No No No No (2) One No No No No (3) One No No No No (4) One No No No One (1) One No No No One (2) One No No No One (3) One No No No One (4) One No (1) No No (1) No No (1) No No (2) No No (1) No No (3) No No (1) No No (4) No No (1) No One (1) No No (1) No One (2) No No (1) No One (3) No No (1) No One (4) No No (1) No No (1) One No (1) No No (2) One No (1) No No (3) One No (1) No No (4) One No (1) No One (1) One No (1) No One (2) One No (1) No One (3) One No (1) No One (4) One No (2) No No (1) No No (2) No No (2) No No (2) No No (3) No No (2) No No (4) No No (2) No One (1) No No (2) No One (2) No No (2) No One (3) No No (2) No One (4) No No (2) No No (1) One No (2) No No (2) One No (2) No No (3) One No (2) No No (4) One No (2) No One (1) One No (2) No One (2) One No (2) No One (3) One No (2) No One (4) One No (3) No No (1) No No (3) No No (2) No No (3) No No (3) No No (3) No No (4) No No (3) No One (1) No No (3) No One (2) No No (3) No One (3) No No (3) No One (4) No No (3) No No (1) One No (3) No No (2) One No (3) No No (3) One No (3) No No (4) One No (3) No One (1) One No (3) No One (2) One No (3) No One (3) One No (3) No One (4) One No (4) No No (1) No No (4) No No (2) No No (4) No No (3) No No (4) No No (4) No No (4) No One (1) No No (4) No One (2) No No (4) No One (3) No No (4) No One (4) No No (4) No No (1) One No (4) No No (2) One No (4) No No (3) One No (4) No No (4) One No (4) No One (1) One No (4) No One (2) One No (4) No One (3) One No (4) No One (4) One One No No No (1) No One No No No (2) No One No No No (3) No One No No No (4) No One No No One (1) No One No No One (2) No One No No One (3) No One No No One (4) No One No No No (1) One One No No No (2) One One No No No (3) One One No No No (4) One One No No One (1) One One No No One (2) One One No No One (3) One One No No One (4) One One (1) No No (1) No One (1) No No (2) No One (1) No No (3) No One (1) No No (4) No One (1) No One (1) No One (1) No One (2) No One (1) No One (3) No One (1) No One (4) No One (1) No No (1) One One (1) No No (2) One One (1) No No (3) One One (1) No No (4) One One (1) No One (1) One One (1) No One (2) One One (1) No One (3) One One (1) No One (4) One One (2) No No (1) No One (2) No No (2) No One (2) No No (3) No One (2) No No (4) No One (2) No One (1) No One (2) No One (2) No One (2) No One (3) No One (2) No One (4) No One (2) No No (1) One One (2) No No (2) One One (2) No No (3) One One (2) No No (4) One One (2) No One (1) One One (2) No One (2) One One (2) No One (3) One One (2) No One (4) One One (3) No No (1) No One (3) No No (2) No One (3) No No (3) No One (3) No No (4) No One (3) No One (1) No One (3) No One (2) No One (3) No One (3) No One (3) No One (4) No One (3) No No (1) One One (3) No No (2) One One (3) No No (3) One One (3) No No (4) One One (3) No One (1) One One (3) No One (2) One One (3) No One (3) One One (3) No One (4) One One (4) No No (1) No One (4) No No (2) No One (4) No No (3) No One (4) No No (4) No One (4) No One (1) No One (4) No One (2) No One (4) No One (3) No One (4) No One (4) No One (4) No No (1) One One (4) No No (2) One One (4) No No (3) One One (4) No No (4) One One (4) No One (1) One One (4) No One (2) One One (4) No One (3) One One (4) No One (4) One No No One No (1) No No No One No (2) No No No One No (3) No No No One No (4) No No No One One (1) No No No One One (2) No No No One One (3) No No No One One (4) No No No One No (1) One No No One No (2) One No No One No (3) One No No One No (4) One No No One One (1) One No No One One (2) One No No One One (3) One No No One One (4) One No (1) One No (1) No No (1) One No (2) No No (1) One No (3) No No (1) One No (4) No No (1) One One (1) No No (1) One One (2) No No (1) One One (3) No No (1) One One (4) No No (1) One No (1) One No (1) One No (2) One No (1) One No (3) One No (1) One No (4) One No (1) One One (1) One No (1) One One (2) One No (1) One One (3) One No (1) One One (4) One No (2) One No (1) No No (2) One No (2) No No (2) One No (3) No No (2) One No (4) No No (2) One One (1) No No (2) One One (2) No No (2) One One (3) No No (2) One One (4) No No (2) One No (1) One No (2) One No (2) One No (2) One No (3) One No (2) One No (4) One No (2) One One (1) One No (2) One One (2) One No (2) One One (3) One No (2) One One (4) One No (3) One No (1) No No (3) One No (2) No No (3) One No (3) No No (3) One No (4) No No (3) One One (1) No No (3) One One (2) No No (3) One One (3) No No (3) One One (4) No No (3) One No (1) One No (3) One No (2) One No (3) One No (3) One No (3) One No (4) One No (3) One One (1) One No (3) One One (2) One No (3) One One (3) One No (3) One One (4) One No (4) One No (1) No No (4) One No (2) No No (4) One No (3) No No (4) One No (4) No No (4) One One (1) No No (4) One One (2) No No (4) One One (3) No No (4) One One (4) No No (4) One No (1) One No (4) One No (2) One No (4) One No (3) One No (4) One No (4) One No (4) One One (1) One No (4) One One (2) One No (4) One One (3) One No (4) One One (4) One One No One No (1) No One No One No (2) No One No One No (3) No One No One No (4) No One No One One (1) No One No One One (2) No One No One One (3) No One No One One (4) No One No One No (1) One One No One No (2) One One No One No (3) One One No One No (4) One One No One One (1) One One No One One (2) One One No One One (3) One One No One One (4) One One (1) One No (1) No One (1) One No (2) No One (1) One No (3) No One (1) One No (4) No One (1) One One (1) No One (1) One One (2) No One (1) One One (3) No One (1) One One (4) No One (1) One No (1) One One (1) One No (2) One One (1) One No (3) One One (1) One No (4) One One (1) One One (1) One One (1) One One (2) One One (1) One One (3) One One (1) One One (4) One One (2) One No (1) No One (2) One No (2) No One (2) One No (3) No One (2) One No (4) No One (2) One One (1) No One (2) One One (2) No One (2) One One (3) No One (2) One One (4) No One (2) One No (1) One One (2) One No (2) One One (2) One No (3) One One (2) One No (4) One One (2) One One (1) One One (2) One One (2) One One (2) One One (3) One One (2) One One (4) One One (3) One No (1) No One (3) One No (2) No One (3) One No (3) No One (3) One No (4) No One (3) One One (1) No One (3) One One (2) No One (3) One One (3) No One (3) One One (4) No One (3) One No (1) One One (3) One No (2) One One (3) One No (3) One One (3) One No (4) One One (3) One One (1) One One (3) One One (2) One One (3) One One (3) One One (3) One One (4) One One (4) One No (1) No One (4) One No (2) No One (4) One No (3) No One (4) One No (4) No One (4) One One (1) No One (4) One One (2) No One (4) One One (3) No One (4) One One (4) No One (4) One No (1) One One (4) One No (2) One One (4) One No (3) One One (4) One No (4) One One (4) One One (1) One One (4) One One (2) One One (4) One One (3) One One (4) One One (4) One

The combination of a flatness measuring roller provided in the set of tension rollers with a flatness measuring roller arranged upstream and/or downstream of the set of tension rollers has the disadvantage that more installation space is required for such an embodiment; however, the provision of a separate tensioning roller in addition to the tensioning roller provided in the tensioning roller set can offer the advantage of being able to calibrate the flatness measuring roller in the tensioning roller set.

• das Band die erste Spannrolle mit einem Umschlingungswinkel von mindestens 90°, insbesondere bevorzugt mindestens 125°, insbesondere bevorzugt mindestens 130°, insbesondere bevorzugt mindestens 145°, insbesondere bevorzugt mindestens 180° umschlingt;
• und/oder das Band die zweite Spannrolle mit einem Umschlingungswinkel von mindestens 90°, insbesondere bevorzugt mindestens 125°, insbesondere bevorzugt mindestens 130°, insbesondere bevorzugt mindestens 145°, insbesondere bevorzugt mindestens 180° umschlingt.

In a preferred embodiment, a belt is guided over the first idler roller and over the second idler roller, wherein

• the belt wraps around the first tensioning roller with a wrap angle of at least 90°, particularly preferably at least 125°, particularly preferably at least 130°, particularly preferably at least 145°, particularly preferably at least 180°;
• and/or the belt wraps around the second tensioning roller with a wrap angle of at least 90°, particularly preferably at least 125°, particularly preferably at least 130°, particularly preferably at least 145°, particularly preferably at least 180°.

In a preferred embodiment of the straightening system according to the invention, the same number of driven tensioning rollers are provided in the front tensioning roller set as in the rear tensioning roller set. In a preferred embodiment, the front and rear tensioning roller sets have the same number of tensioning rollers, with the first tensioning roller designed as a flatness measuring roller being designed without a drive and being arranged either in the front or in the rear tensioning roller set, with the other tensioning roller set not having a flatness measuring roller but a drag roller instead of the flatness measuring roller has, and the remaining tensioning rollers of the respective tensioning roller set are driven, so that in the front tensioning roller set there are just as many driven tensioning rollers as in the rear tensioning roller set.

In a preferred embodiment, the rear set of tensioning rollers of the straightening system is a set of tensioning rollers according to the invention, the first tensioning roller being the tensioning roller of the set of tensioning rollers onto which the strip runs after leaving the stretching zone and/or the bending frame. Additionally or alternatively, the front set of tensioning rollers of the straightening system is a set of tensioning rollers according to the invention, the first tensioning roller being the tensioning roller of the set of tensioning rollers from which the strip runs into the stretching zone and/or the bending frame. Alternatively, in a further preferred embodiment, the front set of tensioning rollers of the straightening system is a set of tensioning rollers according to the invention, the first tensioning roller being the tensioning roller of the set of tensioning rollers, onto which the strip from a decoiler runs.

With the straightening system according to the invention, it is possible to carry out the flatness measurement at the smallest possible distance behind the stretching zone or bending frame. This minimizes the dead zone. The invention makes it possible to use the flatness measuring roller in the high-tension area without interference from the roller drive. The flatness measurement can be carried out in the straightening system in the tension area with just one measuring roller. The straightening system according to the invention makes it possible to carry out flatness measuring roller diameters with the same size as the other tensioning rollers of the tensioning roller set. As a result, bending stresses when the belt is deflected around the roller body can be minimized.

1. a. einen vorderen Spannrollensatz,
2. b. einen hinteren Spannrollensatz,
3. c. ein zwischen dem vorderen Spannrollensatz und dem hinteren Spannrollensatz vorgesehenen Nachwalzgerüst auf,

wobei

• der vordere Spannrollensatz als erfindungsgemäßer Spannrollensatz ausgeführt ist und/oder
• der hintere Spannrollensatz als erfindungsgemäßer Spannrollensatz ausgeführt ist.

The set of tensioning rollers according to the invention can also be used in a re-rolling stand system for re-rolling a strip. The re-rolling mill shows

1. a. a front tensioner set,
2. b. a rear tensioner set,
3. c. a temper rolling stand provided between the front idler set and the rear idler set,

whereby

• the front set of tension rollers is designed as a set of tension rollers according to the invention and/or
• the rear idler set is designed as an idler set according to the invention.

The above disclosure for embodiments of the straightening system according to the invention is also intended to serve as a disclosure for embodiments of the post-salting stand system according to the invention, the disclosure relating to the re-salting stand system being formed in that the term “straightening system” is replaced by “re-rolling stand system” and the term “stretching zone” by roll stand and the term “ bending stand" is replaced by a rolling stand.

A method according to the invention for operating a straightening system according to the invention, which has a bending frame with an adjustable bending roller and a control device, provides that the control device carries out control interventions on at least one actuator of the straightening system, for example the adjustable bending roller or the sets of tension rollers, based on measurement results from the force sensor.

A method according to the invention for operating a re-rolling stand system according to the invention, which has an adjustable roll and a control device, provides that the control device carries out control interventions on at least one actuator of the re-rolling stand system, for example the adjustable roll or the sets of tension rollers, based on measurement results from the force sensor.

A supplementary or alternative method according to the invention for operating a straightening system according to the invention or a re-rolling stand system according to the invention, which is designed such that an auxiliary drive is provided for the first tensioning roller, with which a torque about the first roller axis can be applied to the first tensioning roller, the auxiliary drive for the first tensioning roller is weaker than the drive for the second tensioning roller, provides that after a start-up phase and/or after the belt tension has built up, the auxiliary drive for the first tensioning roller is switched off or is regulated to a drive torque of 0 Nm.

In particular, the start-up phase involves threading the belt and accelerating the system to operating speed.

With the tension roller set according to the invention, the method can DE 10 2019 006 788 be performed.

The invention is used particularly preferably in the straightening and/or re-rolling of strip material, preferably metal strips or sheet metal.

Fig. 1

eine schematische Seitenansicht einer erfindungsgemäßen Richtanlage;

Fig. 2

eine schematische Seitenansicht einer weiteren erfindungsgemäßen Richtanlage und

Fig. 3

eine schematische Darstellung der auf eine Messrolle wirkenden Kräfte.

The invention is explained in more detail below with reference to drawings that merely show embodiments of the invention in more detail. Show in it:

1

a schematic side view of a straightening system according to the invention;

2

a schematic side view of another straightening system according to the invention and

3

a schematic representation of the forces acting on a measuring roller.

In the 1 Straightening system 1 shown for straightening a strip 2 has a front set of tension rollers 3 and a rear set of tension rollers 4 . A bending frame 5 is provided between the front tensioning roller set 3 and the rear tensioning roller set 4 . A reel 6 is provided in front of the front tension roller set 3 . A reel 7 is provided behind the rear tension roller set 4 .

The strip 2 is unwound from the reel 6, passes through the front set of tension rollers 3, passes through the bending frame 5, passes through the rear set of tension rollers 4 and is wound up by the reel 7. The strip tension acting on the strip 2 is increased in the front set of tension rollers 3, while the strip tension acting on the strip 2 is reduced in the rear set of tension rollers 4, so that the strip tension acting on the strip 2 is higher in the area of the bending frame 5 than in front of the front Tensioner set 3 and after the rear tensioner set 4.

• eine erste Spannrolle 8 mit einer ersten Rollenachse,
• eine zweite Spannrolle 9 mit einer zweiten Rollenachse,
• eine dritte Spannrolle 10 mit einer dritten Rollenachse,
• eine vierte Spannrolle 11 mit einer vierten Rollenachse,

auf, wobei die erste Spannrolle 8 eine Planheitsmessrolle ist, die einen Kraftsensor zum Messen einer auf die Umfangsfläche der Planheitsmessrolle ausgeübten Radialkraft (FR,1) aufweist.The rear idler set 4 has

• a first tensioning roller 8 with a first roller axis,
• a second tensioning roller 9 with a second roller axis,
• a third tensioning roller 10 with a third roller axis,
• a fourth tensioning roller 11 with a fourth roller axis,

, the first tensioning roller 8 being a flatness measuring roller which has a force sensor for measuring a radial force (FR,1) exerted on the peripheral surface of the flatness measuring roller.

A drive (not shown) for the second tensioning roller 9 is provided, with which a torque about the second roller axis can be applied to the second tensioning roller 9 . Furthermore, a (also not shown) drive for the third tensioning roller 10 is provided, with which a torque to the third Roller axis can be applied to the third tensioning roller 10. Furthermore, a drive (likewise not shown) for the fourth tensioning roller 11 is provided, with which a torque about the fourth roller axis can be applied to the fourth tensioning roller 11 .

The first tensioning roller 8 is designed without a drive.

• eine erste Spannrolle 14 mit einer ersten Rollenachse,
• eine zweite Spannrolle 15 mit einer zweiten Rollenachse,
• eine dritte Spannrolle 16 mit einer dritten Rollenachse,
• eine vierte Spannrolle 17 mit einer vierten Rollenachse,

auf. Ein (nicht näher dargestellter) Antrieb für die zweite Spannrolle 15 ist vorgesehen, mit dem ein Drehmoment um die zweite Rollenachse auf die zweite Spannrolle 15 aufgebracht werden kann. Ferner ist ein (ebenfalls nicht näher dargestellter) Antrieb für die dritte Spannrolle 16 vorgesehen, mit dem ein Drehmoment um die dritte Rollenachse auf die dritte Spannrolle 16 aufgebracht werden kann. Ferner ist ein (ebenfalls nicht näher dargestellter) Antrieb für die vierte Spannrolle 17 vorgesehen, mit dem ein Drehmoment um die vierte Rollenachse auf die vierte Spannrolle 17 aufgebracht werden kann.The front idler set 3 has

• a first tensioning roller 14 with a first roller axis,
• a second tensioning roller 15 with a second roller axis,
• a third tensioning roller 16 with a third roller axis,
• a fourth tensioning roller 17 with a fourth roller axis,

on. A drive (not shown) for the second tensioning roller 15 is provided, with which a torque about the second roller axis can be applied to the second tensioning roller 15 . Furthermore, a drive (likewise not shown in detail) is provided for the third tensioning roller 16, with which a torque about the third roller axis can be applied to the third tensioning roller 16. Furthermore, a drive (likewise not shown) for the fourth tensioning roller 17 is provided, with which a torque about the fourth roller axis can be applied to the fourth tensioning roller 17 .

The first tensioning roller 14 is designed without a drive.

In the 2 shown straightening system 1 differs from that in 1 shown straightening system 1 by the structure of the rear set of tension rollers 4 and the structure of the front set of tension rollers 3. In addition to the first tension roller 8, the second tension roller 9, the third tension roller 10 and the fourth tension roller 11, this has a fifth tension roller 12 and a sixth tension roller 13 .

A drive (not shown) for the second tensioning roller 9 is provided, with which a torque about the second roller axis can be applied to the second tensioning roller 9 . Furthermore, a drive (also not shown in detail) is provided for the third tensioning roller 10, with which a torque about the third roller axis can be applied to the third tensioning roller 10. Furthermore, a drive (likewise not shown) for the fourth tensioning roller 11 is provided, with which a torque about the fourth roller axis can be applied to the fourth tensioning roller 11 . Furthermore, a drive (also not shown) for the fifth tensioning roller 12 is provided, with which a torque about the fifth roller axis can be applied to the fifth tensioning roller 12 .

The first tensioning roller 8 and the sixth tensioning roller 13 are non-driven.

• eine erste Spannrolle 14 mit einer ersten Rollenachse,
• eine zweite Spannrolle 15 mit einer zweiten Rollenachse,
• eine dritte Spannrolle 16 mit einer dritten Rollenachse,
• eine vierte Spannrolle 17 mit einer vierten Rollenachse,

auf. Ein (nicht näher dargestellter) Antrieb für die zweite Spannrolle 15 ist vorgesehen, mit dem ein Drehmoment um die zweite Rollenachse auf die zweite Spannrolle 15 aufgebracht werden kann. Ferner ist ein (ebenfalls nicht näher dargestellter) Antrieb für die dritte Spannrolle 16 vorgesehen, mit dem ein Drehmoment um die dritte Rollenachse auf die dritte Spannrolle 16 aufgebracht werden kann. Ferner ist ein (ebenfalls nicht näher dargestellter) Antrieb für die vierte Spannrolle 17 vorgesehen, mit dem ein Drehmoment um die vierte Rollenachse auf die vierte Spannrolle 17 aufgebracht werden kann. Ferner ist ein (ebenfalls nicht näher dargestellter) Antrieb für die erste Spannrolle 14 vorgesehen, mit dem ein Drehmoment um die erste Rollenachse auf die erste Spannrolle 14 aufgebracht werden kann.The front tension roller set 3 in the embodiment of 2 points

• a first tensioning roller 14 with a first roller axis,
• a second tensioning roller 15 with a second roller axis,
• a third tensioning roller 16 with a third roller axis,
• a fourth tensioning roller 17 with a fourth roller axis,

on. A drive (not shown) for the second tensioning roller 15 is provided, with which a torque about the second roller axis can be applied to the second tensioning roller 15 . Furthermore, a drive (likewise not shown in detail) is provided for the third tensioning roller 16, with which a torque about the third roller axis can be applied to the third tensioning roller 16. Furthermore, a drive (likewise not shown) for the fourth tensioning roller 17 is provided, with which a torque about the fourth roller axis can be applied to the fourth tensioning roller 17 . Furthermore, a drive (likewise not shown in detail) is provided for the first tensioning roller 14, with which a torque about the first roller axis can be applied to the first tensioning roller 14.

3 shows the forces applied to the measuring roller by a metal strip that is partially wrapped around the measuring roller and is under strip tension. The quartz force sensors located in recesses in the measuring roller generate an electrical charge. This is directly proportional to the force applied to the quartz.

mit

• F_R,i = Örtliche Radialkraft in N (Sensorkraft)
• r_Roll = Radius der Messrolle
• A_Sensor = Fläche des Sensors bzw. des Deckels auf dem Sensor, der mit dem Band in Kontakt ist.
• d = Banddicke

The strip length deviation, usually measured in I-units and commonly used as a representative of strip flatness, can be calculated using the following relationships:
Local tensile stress in band section i $$\mathrm{\sigma Z}\mathrm{,\; i}=\mathrm{FR},\mathrm{i}\times \mathrm{r\_Roll/}\left(\mathrm{A}\_\mathrm{sensor}\times \mathrm{i.e}\right)$$

With

• F_R,i = local radial force in N (sensor force)
• r_Roll = radius of the measuring roll
• A_Sensor = Area of the sensor or cap on the sensor that is in contact with the tape.
• d = band thickness

mit
δ Z,max = Maximum aller örtlicher ZugspannungenTension deviation of the strip section from the strip section with maximum tensile stress: $$\Delta \mathrm{\delta }\mathrm{Z},\mathrm{i}=\mathrm{\delta }\mathrm{Z},\mathrm{I}-\mathrm{\delta }\mathrm{Z},\mathrm{Max}$$

With
δ Z,max = maximum of all local tensile stresses

mit
E = E-ModulLocal strip length deviation (flatness): $$\Delta \mathrm{L}/\mathrm{Li}=-\Delta \mathrm{\delta }\mathrm{Z},\mathrm{i}/\mathrm{E}$$

With
E = Young's modulus

Example:

• FR,i = 500 N
• r_Roll = 300mm
• A_Sensor = 707mm ²
• d = 0.5mm
• δZ,1 = 424.4 MPa
• δZ,max = 430 MPa
• ΔδZ,I = -5.59 MPa
• E = 206GPa
• ΔL/Li = 27.1 µm/m = 2.71 I units

Claims (13)

Set of tension rollers (3, 4) for a straightening system (1) for straightening a strip (2) or for a re-rolling stand for re-rolling a strip, the set of tension rollers (3, 4) • a first tensioning roller (8) with a first roller axis and • has at least one second tensioning roller (9) with a second roller axis, wherein the first tensioning roller (8) is a flatness measuring roller which has a force sensor for measuring a radial force exerted on the peripheral surface of the flatness measuring roller, and a drive for the second tensioning roller (9) is provided, with which a torque about the second roller axis can be applied to the second tensioning roller (9), characterized in that • either the first tensioning roller (8) is non-driven • or an auxiliary drive is provided for the first tensioning roller, with which a torque about the first roller axis can be applied to the first tensioning roller, the auxiliary drive for the first tensioning roller being weaker than the drive for the second tensioning roller. Tensioning roller set (3, 4) according to claim 1, characterized by a third tensioning roller (10) with a third roller axis and a fourth tensioning roller (11) with a fourth roller axis, wherein a. a drive for the third tensioning roller (10) is provided, with which a torque about the third roller axis can be applied to the third tensioning roller (10),
and or b. a drive for the fourth tensioning roller (11) is provided, with which a torque about the fourth roller axis can be applied to the fourth tensioning roller (11). Tensioning roller set (3, 4) according to claim 2, characterized by a fifth tensioning roller (12) with a fifth roller axis, with a drive for the fifth Tensioning roller (12) is provided, with which a torque about the fifth roller axis can be applied to the fifth tensioning roller (12). Tensioning roller set (3, 4) according to one of Claims 1 to 3, characterized in that the drive for the second tensioning roller (9) can apply a maximum torque T2 about the second roller axis to the second tensioning roller (9) and that the auxiliary drive for the first tensioning roller (8) can apply a maximum torque T1 about the first roller axis to the first tensioning roller (8), where T1 is equal to or less than half of T2. Tension roller set (3, 4) according to one of Claims 1 to 4, characterized in that the flatness measuring roller has an axial bore running parallel to the first roller axis and in that the force sensor is arranged in the axial bore. Tension roller set (3, 4) according to one of Claims 1 to 5, characterized in that the flatness measuring roller has a surface coating. Tension roller set (3, 4) according to one of claims 1 to 6, characterized in that a band (2) is guided over the first tension roller (8) and over the second tension roller (9) and the band (2) the first tension roller ( 8) with a wrap angle of at least 90° and/or the belt (2) wraps around the second tensioning roller (9) with a wrap angle of at least 90° Straightening system (1) for straightening a strip (2). a. a front tensioner set (3), b. a rear tensioner set (4), c. a stretching zone provided between the front set of tension rollers (3) and the rear set of tension rollers (4) and/or a bending frame (5) provided between the front set of tension rollers (3) and the rear set of tension rollers (4), characterized in that • the front idler assembly (3) is an idler assembly according to any one of claims 1 to 7
and or • the rear idler assembly (4) is an idler assembly according to any one of claims 1 to 7. Straightening system (1) according to claim 8, characterized in that a. the rear tensioning roller set (4) is a tensioning roller set according to any one of claims 1 to 7 and that the first tensioning roller (8) is the tensioning roller of the tensioning roller set on which the belt (2) runs first and/or b. the front idler set (3) is an idler set according to any one of claims 1 to 7 and in that the first idler (8) is the idler of the idler set from which the belt (2) comes off last. Tempering stand system for tempering a strip (2) with a. a front tensioner set (3), b. a rear tensioner set (4), c. a re-rolling stand provided between the front set of tension rollers (3) and the rear set of tension rollers (4), characterized in that • the front tensioning roller set (3) is a tensioning roller set according to one of claims 1 to 7 and/or • the rear idler assembly (4) is an idler assembly according to any one of claims 1 to 7. Method for operating a straightening system (1) according to one of Claims 8 or 9, the straightening system (1) having a bending frame (5) with adjustable bending rollers and having a control device, characterized in that the control device, on the basis of measurement results from the force sensor, carries out control interventions on at least one Actuator of the straightening system makes. Method for operating a re-rolling stand according to claim 10, wherein the re-rolling stand has adjustable rolls and a control device, characterized in that the control device carries out control interventions on at least one actuator of the re-rolling stand on the basis of measurement results from the force sensor. Method for operating a straightening system (1) according to one of Claims 8 or 9 or a re-rolling stand system according to Claim 10, in which the set of tensioning rollers (3, 4) is designed according to one of Claims 1 to 7 in such a way that an auxiliary drive for the first tensioning roller ( 8) is provided, with which a torque about the first roller axis can be applied to the first tensioning roller (8), the auxiliary drive for the first tensioning roller (8) being designed to be weaker than the drive for the second tensioning roller (9), thereby characterized in that after a start-up phase or after application of the belt tension, the auxiliary drive for the first tensioning roller (8) is switched off or is regulated to a torque of 0 Nm.

Images