EP0611717A1 - Method and device for turning a running steel strip - Google Patents

Abstract

In the passage of a steel strip through a continuous strip treatment plant, the "good side" of the strip is occasionally turned, for the purpose of checking, from the bottom side to the top side, or vice versa. Between stations of the plant, the strip is introduced into a strip-turning tower and is guided in the latter successively over vertically spaced upper and lower deflection rollers, being twisted in the process from roller to roller by in each case an angular amount, in such a way that between strip entry and strip exit it is set into any desired angle and is occasionally twisted in such a way that, after deflection through 180@, the bottom side of the strip on entry into the first roller is turned to the top side of the strip on exit, and vice versa. The device provided for this has a strip-turning tower (20), of similar construction to a vertical looping store, with a number of vertically spaced upper (21) and lower (22) strip deflection rollers, the rollers being arranged rotated in the running direction of the strip (30) from roller (21) to roller (22) by angular amounts (Phi1 to Phin), in the same direction, relative to the strip entry axis (x-x), in such a way that the strip (30), on winding round in each case one roller pair formed by a lower (22) and an upper (21) roller, is twisted by the angular amount (Phi) and if all of the twisting angular amounts are added up it is eventually turned through 180@. <IMAGE>

Description

The invention relates to a method and a device for guiding a steel strip during its passage through a continuous strip treatment system equipped with a series of treatment stations, the direction and / or track of the strip being set as desired and / or the strip being removed from the strip for control purposes by visual inspection Bottom to top - or vice versa - is turned.

A known treatment plant for steel strip comprises, for example, stations for a continuous sequence of treatment steps such as degreasing, annealing, galvanizing, skin-dressing, painting, checking, winding, etc. In such a hot-dip galvanizing and painting plant, as is shown by way of example in FIG the so-called "good side" of the strip is turned from the underside to the top in order to make it accessible for inspection by visual inspection, the underside of the strip emerging from the galvanizing bath initially continuing in the continuous strip running direction The underside of the band remains. When dressing, for example by roughening the surface of the belt and then winding it up, the underside of the belt must then be turned towards the top of the belt for continuous visual inspection.

For this purpose, the strip is fed vertically upwards into a steel structure below the high hall roof in the longitudinal direction over the system parts, at the end of the hall vertically downwards and then horizontally against the belt running direction of the inlet part of the system for further treatment and winding. The belt is transported just below the roof of the approx. 40 m high hall via the outlet group with outlet loop tower and further via the coating device. This requires a long, stable and high steel construction with idlers for guiding the belt as well as a built-in crane for handling the plant components underneath. The required high hall is correspondingly long, for example 150 m. This results in a further disadvantage because the long horizontal distance of the high-lying belt guide can lead to belt running problems and belt damage on the idlers.

The invention has for its object to provide a method and an apparatus for guiding a steel strip during its passage through a continuous strip treatment system, which avoids the aforementioned difficulties, in particular when transferring the strip in the area of the roof structure of the hall, and consequently a substantial reduction in the high Hall construction and at the same time improved belt guidance, preferably while maintaining the tape running direction through the system. In addition, it should also be possible with the method and the device to set the running direction of the belt as desired and to follow a track z. B. set up with parallel offset.

The object is achieved with the invention by a method according to the features of claim 1. One embodiment provides that the band is twisted by an angular amount (Phi) of 180 ^{o in} total, such that at the end of the deflections by 180 ^o the underside of the belt is turned when entering the first roll of the belt turning tower to the top of the belt when it is discharged from the last roll, and vice versa.

Advantageously, the belt is guided in the belt turning tower within a comparatively short horizontal distance, respectively via deflection rollers arranged below and above, and twisted from roll to roll by an angle (Phi), so that in the event of a deflection around the last lower roll with a total of 180 ^o the underside of the belt at the inlet is turned towards the top of the belt at the outlet. This also results in a shorter and lower hall construction and a more controllable belt guide. As a further advantage, the belt running direction can be maintained unchanged through the entire system if necessary, which provides a better overview and control over the individual stations of the continuous belt processing system.

However, the belt can also be adjusted in its running direction or be guided through parts of the system with its tracks running parallel to one another.

Due to the twisting of the belt within the belt turning tower, increased edge stresses occur on the belt. These must lie within the elastic range and are compensated for by suitable measures. For this purpose, an embodiment provides that the permissible twist angle (Phi) of the band between an upper and a lower roll depends on the ratio of the free length (L) of the band between the two rolls to the band width (B) and the resulting permissible edge tension (Sigma) of the tape is determined.

Another measure for reducing the wheel tensions of the belt when it is twisted between two rollers is, according to the invention, that crowned rollers are used in the belt turning tower.

For this purpose, an embodiment provides that the crowning-determining diameter difference (D - D ') of a roll is approximately the amount that arises between a pair of rolls and one due to the band being twisted by an angle (Phi) for a given free band length (L) of the band Elongation of the band edge areas causing the edge extension (Delta L) corresponds.

According to an additional embodiment, it can further be provided that length differences or tension differences of the belt within the belt turning tower by correcting the vertical distances be compensated for between the lower and the upper roles interacting with them. This makes the arrangement of an additional loop storage unnecessary.

In the event that a parallel offset of the running tracks of the belt is required, one embodiment of the invention provides that the belt in the deflecting tower is pivoted in the passage through a first group of rollers to an angle which deviates from the direction of its entry track and after passing through a straight intermediate section corresponding to the amount of the lateral displacement in a second group of deflection rollers is swiveled back into the original direction of its entry track.

In this embodiment of the invention, there is also the possibility that for compensating for a lateral displacement caused by the diverting pulleys in the belt contact (S), the tape ^o twisted more than 180 in a first group of deflection rollers at least an angular amount, the angle (beta) to the belt inlet axis (xx) out of the last, lower roller in a piece of straight longitudinal guide in the direction against the tape outlet axis (yy), by the amount (S) of the lateral offset into a second group of deflection rollers and an angular amount in the direction of the Belt inlet axis (xx) coaxial belt outlet axis (yy) is pivoted. With this measure, the strip is returned within the tower while maintaining the strip running track through the center of the system from start to finish. Appropriately, as is customary in the case of loop towers, means for controlling the center of the strip are provided in front of and behind the belt turning tower.

A device for guiding a steel strip in a treatment plant for steel strip, the plant having stations for continuous sequences of treatment steps such as degreasing, annealing, galvanizing, skin-dressing, painting, checking, winding, etc., for carrying out the method according to the invention, is characterized by a Kind of a vertical loop storage trained belt turning tower with a number of vertically spaced upper and lower belt deflection rollers, these in the direction of the belt from roll to roll in the same direction, occasionally to 180 ^o cumulative angular amounts (Phi₁ to Phi _n ) relative to the tape inlet axis (xx) are arranged twisted, such that the belt twisted by wrapping a pair of rollers formed by a lower and an upper roller by an angular partial amount (Phi) and occasionally with a sum of all twist angle amounts (Phi₁ to Phi _n ) of 180 ^o from the U underside to the top - and vice versa. By wrapping each roll around 180 ^o, good guidance and protection of the belt surface are achieved.

An additional embodiment can be provided, according to which the upper deflection rollers have means for adjusting the vertical distance from the lower rollers. In this way, differences in length of the strip within the strip turning tower can be compensated for in a simple manner without additional provision of a loop storage device. In addition, a further embodiment can provide that the upper rollers of the turning device have means for setting and preferably keeping the tension state constant in the continuous belt. Such Means can be, for example, hydraulic piston / cylinder units which hold the upper rollers in a predetermined tension state of the rotating belt. The means for length and voltage compensation can form a unit.

By means of convex deflection rollers, preferably the difference in diameter between the center and end face of a spherical roller corresponds approximately to the amount of the edge elongation of the ribbon caused by twisting the ribbon by an angular amount (Phi) for a given bandwidth and center distance of the rollers, the ribbon becomes effective from increased edge tensions relieved, while the tape guide properties of the rollers are also improved. It is also an uncomplicated measure.

A special embodiment provides that the belt turning tower has two separate groups of roller pairs which are connected to one another by a straight running path of the belt in the direction of a belt outlet axis (yy) coaxial to the belt inlet axis (xx), the sum of the angular amounts of both groups preferably accumulates to 180 ^o . This configuration ensures that the belt run is maintained in a line through the center of the system from the inlet to the outlet of the belt.

If, in addition, the straight running path is extended to such an extent that it corresponds to the amount of a predetermined distance from two parallel tracks, any parallel offset during the tape transport can be set with this device. Even with one appropriate combination of twist angles any setting of the tape running direction can be achieved.

Another essential embodiment provides that the upper and lower rollers, as seen in the vertical projection, are assigned to one another in such a way that the side lines of two rollers leading a common belt section and rotated relative to one another by an angular amount (Phi) each intersect in half their length . This measure ensures in a simple manner that the belt maintains a secure center guidance on each roll when running through the successive pairs of rolls.

Further details, features and advantages of the invention result from the following explanation of some exemplary embodiments shown schematically in the drawings.

Fig. 1

in Seitenansicht eine herkömmliche kombinierte Feuerverzinkungs- und Lackieranlage;

Fig. 2

die Feuerverzinkungs- und Lackieranlage mit einem erfindungsgemäßen Bandwendeturm;

Fig. 3a-3c

schematische Darstellungen unterschiedlicher Verdrillungsmöglichkeiten beim Bandwenden, z.B. mit 2 x 90^o (Fig. 3a) bzw. 4 x 45^o (Fig. 3b) bzw. 6 x 60^o (Fig. 3c);

Fig. 4

eine Seitenansicht eines Bandwendeturms;

Fig. 5

eine vertikale Projektion des Bandwendeturms;

Fig. 6a-6c

schematische bzw. diagrammatische Darstellungen der erforderlichen freien Bandlängen (L) beim Verschränken von Bändern unterschiedlicher Bandbreiten;

Fig. 7a-7b

schematische Darstellungen der Kompensation von Verdrillungs-Randspannungen mittels balliger Führungsrollen;

Fig. 8

eine schematische Darstellung eines Bandwendeturms mit peripher angeschlossenen Transportspuren für den Bandtransport zwischen unterschiedlichen Behandlungsstationen einer Anlage.

Show it:

Fig. 1

a side view of a conventional combined hot-dip galvanizing and painting system;

Fig. 2

the hot-dip galvanizing and painting system with a belt turning tower according to the invention;

3a-3c

schematic representations of different twisting options when turning the tape, for example with 2 x 90 ^o (Fig. 3a) or 4 x 45 ^o (Fig. 3b) or 6 x 60 ^o (Fig. 3c);

Fig. 4

a side view of a belt turning tower;

Fig. 5

a vertical projection of the belt turning tower;

6a-6c

schematic or diagrammatic representations of the required free tape lengths (L) when interlacing tapes of different bandwidths;

Figures 7a-7b

schematic representations of the compensation of twisting edge stresses by means of spherical guide rollers;

Fig. 8

is a schematic representation of a belt turning tower with peripherally connected transport tracks for the belt transport between different treatment stations of a system.

Fig. 1 shows a combined hot-dip galvanizing and painting system in a conventional design with a first low hall part (40) and a subsequent approximately 40 m high and 150 m long hall component (41). In the low hall (40) there is the inlet group (1), in which tapes (30a, 30b) that can be unwound from two coils are combined to form an endless belt (30), which is then passed through a degreasing station (2) followed by a horizontal one Loop storage (3) is inserted into the high hall part (41). The strip (30) is first passed through a glow station (4) annealed without tension, and after passing through a downstream cooling device (5) in the galvanizing station (6) galvanized. After passing through another cooling section (7), the belt is vertically upwards into a steel structure (8) and horizontally below the roof of the high hall (41) at a height of approx. 40 m above the system parts (9 - 12) at the end of the hall vertically downwards and then again horizontally in the opposite direction of the belt run to the inlet part (1) for further treatment, first through skin pass stands (9), then through a straightening / straightening device (10) and out of this through the fully automatic painting device (11). From this the galvanized and coated strip passes through a vertical discharge loop tower attached to the coating device into the discharge group (12) and is wound there on coils. At the locations marked with "X", e.g. B. at the exit of the strip (30) from the galvanizing (6), between the skin pass mill (9) and in the outlet group (12), the strip (30) is subjected to a check by visual inspection (X). For this purpose, the original underside (33) of the band (30) is turned over to the band top (34). This is done in the conventional design of the system by turning 2 x 90 ^o in the vertical section (35) between the steel structure (8) and the inlet into the skin pass mill (9). It can be seen that for the height of the hall (41), its length and the required high and long steel structure (8) this requires a comparatively extremely high effort to turn the belt (30). Another disadvantage is that the tape runs in opposite directions. There is also a risk that the tape in the high Steel structure (8) is damaged by imprecise and difficult to monitor barrel.

A system according to the present invention with a belt turning tower (20) is shown in FIG. 2. The belt turning tower (20) is arranged between the galvanizing station (6) and its downstream cooling section (7) and the skin pass mill (9) approximately in the first third of the high hall (41). By installing the belt turning tower (20) it is achieved that the high and expensive hall construction is shortened by approx. 40 m and the shortened part is replaced by a lower hall (42) accommodating the outlet group (12). Their height is approx. 15 m compared to approx. 35 m of the high hall. The incoming with the underside of the belt (33) belt (30) ^o turned 180 in the strip turning tower (20) and interacts with the "good side" as the tape top side (34) of the belt turning tower (20).

Different possibilities for turning the tape by 180 ^o are shown in FIGS. 3a to 3c using three examples. When tape contact with only three rollers (21, 22) corresponding to Figure 3a, the band (30) is twisted about 2 x 90 ^o, wherein very high edge stresses occur. These could only be compensated for within tolerable limits by a very large free tape length (L), which would, however, require an uneconomically high outlay. When using five rollers (21, 22) according to Figure 3b, there are four twists with an angle of 45 ^o to a total of 180 ^o . Even more favorable conditions are obtained as shown in Fig. 3c by six twists to each 30 ^o with 7 rollers (21, 22) with a substantially reduced length (L). The same "good sides" of the belt (30) are at the inlet as the underside (33) and at Spout designated as top (34) with the inspection side (X).

According to the illustration in FIG. 4, the belt turning tower (20) is designed with a number of upper (21) lower (22) belt deflection rollers arranged at a vertical distance, similar to a vertical loop storage device. The upper belt deflection rollers (21) and the lower rollers (22) arranged between the first and last lower rollers (22c, 22d) are in the direction of travel of the belt (30) from roller (21) to roller (22) and vice versa in the same direction, to 180 ^o cumulative angular amounts (Phi₁ to Phi _n ) rotated relative to the tape inlet axis (xx). This arrangement can be seen particularly well from FIG. 5. The strip (30) when the wrap is in each case an image formed by a bottom (22) and an upper (21) roller roller pair by the angular amount (Phi) twisted and finally ^o turned in the sum of the twist angle amounts to 180th The guy length is marked with (L), the tape entry axis with (xx) and the coaxial tape exit axis with (yy).

In FIG. 4 it is also shown purely schematically that the upper deflection rollers (21) of the turning device (20) can have means (25) for adjusting the vertical distance (L) to the lower rollers (22, 22c, 22d). Such a possible change in distance is designated in FIG. 4 by "D". The means for adjusting the distance are indicated purely schematically with arrows (25). The upper rollers (21) means (25) both for adjusting the tape length and for keeping the Have tension state in the continuous band (30). Such means (25) can be identical to one another and can consist, for example, of piston / cylinder units. In Figure 4 it is further shown that the tape entry axis (xx) with the underside "U" enters the tape turning tower (20) and after twisting the tape by a total of 180 ^o with the same tape side, but now as the top "O" for Belt exit axis (yy) exits.

A return of the belt (30) within the turning tower (20) ensures, if necessary, the retention of the belt run in a line from the beginning to the end of the system and thus the coaxiality between the belt inlet axis (xx) and the belt outlet axis (yy). This is achieved in that, according to FIG. 5, the belt turning device of the belt turning tower (20) has two groups (20A) or (20B) of roller pairs (21a; 22a) or (21b; 22b); which are connected to one another by a straight belt running path (31) of the belt (30) which runs at an angle (Beta) to the axis (xx). The angular amounts (Phi₁ to Phi _n ) of the two groups (20A) and (20B) add up to 180 ^o .

FIG. 6a shows the twisting of a band section (32) at a center distance (L) between an upper roller (21) and a lower roller (22) in a purely schematic manner. A central rolling process and exact running of the belt section (32) is ensured in that the upper and lower rollers (21, 22), as seen in the vertical projection in FIG. 6b, are assigned to one another in such a way that the side lines (28 and 29 ) two rollers (21 or 22) intersect in the area of the belt centers (xx) or (yy) of half the belt widths (B / 2). In compliance with this condition, the band section (32) is reliably guided with its band center lines (xx) or (yy) over the center of each crowned roll (21 or 22).

• (1) $\text{L + Delta L = √}\overline{\text{L² + (B/2)²}}$
  
• (2) $\text{Delta L (\%) = ( √}\overline{\text{L² + (B/2)²}}\text{- L) * 100 / L}$
  
  
  Delta L (%) = 0,0312 %
• (3) $\text{Delta L / L = Sigma / E ; Sigma = Delta L * E / L}$
  
  
     Sigma = 65,6 N/mm²

Hierin bedeuten:

B

= Bandbreite

L

= Längenabstand Rollenachse/Rollenachse

Delta L

= Kantenverlängerung

Sigma

= resultierende Randkantenspannung

E

= Elastizitätsmodul des Bandmaterials

überschlägig ergibt sich bei einem Verdrillungswinkel von Phi = 30 ^o ca. 30 %; demnach Sigma = 22 N/mm² bei Delta L = 3,1 mm. Danach wird die erforderliche Balligkeit zur Entlastung der Bandkantenspannung (Sigma) angenommen mit $\text{Delta D = D - D' = 3,1 mm}$

.It can be seen from examples that edge stretching results in edge tension when twisting the band (30). For example, when turning 90 ^o between two rollers with the center distance (L), there is an edge extension (L) plus (Delta L) according to the following calculation:
e.g. B. for twisting by 90 ^o with
B = 1,500 mm and
L = 30,000 mm results according to FIG. 7a:

• (1) $\text{L + Delta L = √}\overline{\text{L² + (B / 2) ²}}$
  
• (2) $\text{Delta L (\%) = (√}\overline{\text{L² + (B / 2) ²}}\text{- L) * 100 / L}$
  
  
  Delta L (%) = 0.0312%
• (3) $\text{Delta L / L = Sigma / E; Sigma = Delta L * E / L}$
  
  
  Sigma = 65.6 N / mm²

Here mean:

B

= Bandwidth

L

= Distance between roller axis / roller axis

Delta L

= Edge extension

Sigma

= resulting edge tension

E

= Modulus of elasticity of the strip material

roughly with a twist angle of Phi = 30 ^o approx. 30%; therefore Sigma = 22 N / mm² at Delta L = 3.1 mm. Then the crowning required to relieve the strip edge tension (Sigma) is assumed $\text{Delta D = D - D '= 3.1 mm}$

.

Der zweite Ausdruck in der Wurzel ist gegenüber der Zahl 1 immer klein, so daß angenähert gilt:

$\text{L' = L [ 1 + 1/2 (B * Pi * Phi / L / 360)² ]}$

Damit beträgt die Dehnung der Bandränder:

Die Dehnung muß durch die Bandzugkraft aufgebracht werden, wobei sie linear zur Bandmitte hin abklingt.

Bei Verdrillung Phi = 90^o ist

${\text{F}}_{\text{Z}}\text{/ (B * h * E) = 1/4 (Pi/4 * B/L)²}$

Aufgelöst nach Verdrillungslängen (L) ergibt sich:

$\text{L = Pi/8 * √}\overline{{\text{B³ * h * E / F}}_{\text{Z}}}$

$\text{L = B * Pi * Phi / 720 * √}\overline{{\text{E / F}}_{\text{spez}}}$

Hierin bedeuten:

Epsilon

= die durch Bandkraft aufzubringende Banddehnung

Epsilon_R

= Randkantendehnung

Epsilon_m

= mittlere Dehnung über die Bandbreite

F_Z

= zulässige Bandkraft

F_spez

= spezifischer Bandzug

h

= Banddicke

Phi

= Verdrillungswinkel

Nach diesen Berechnungen ergeben sich die notwendigen freien Bandlängen (L) für Bandbreiten (B) zwischen 650 und 1980 mm für unterschiedliche Verdrillungswinkel (Phi) zwischen den Rollen (21) bzw. (22) in Abhängigkeit von einem spezifischen Bandzug (F_spez) und der Randkantenspannung (Sigma) in N/mm² und entsprechend die notwendigen Abspannlängen (L) in Metern gemäß Diagramm in Figur 6. Im vorliegenden Ausführungsbeispiel nach der Erfindung wurden 6 Umlenkungen mit je einem Winkel (Phi) von 30^o bei einer Bandbreite B = 1700 mm und einer Abspannlänge (L) von 30 m gewählt. Aus dem Diagramm gemäß Fig. 6 geht hervor, daß für diese Verhältnisse ein spezifischer Bandzug (F_spez) von ca. 12 N/mm² resultiert.When twisted, the center line of the tape remains unchanged long, while the edges must lengthen according to the law of a helix. This results in:

The second expression in the root is always small compared to the number 1, so that approximately applies:

$\text{L '= L [1 + 1/2 (B * Pi * Phi / L / 360) ²]}$

The stretching of the band edges is:

The stretch must be applied by the tape tension, which declines linearly towards the middle of the tape.

When twisted, Phi = 90 ^o

${\text{F}}_{\text{Z.}}\text{/ (B * h * E) = 1/4 (Pi / 4 * B / L) ²}$

Dissolved according to the twist lengths (L):

$\text{L = Pi / 8 * √}\overline{{\text{B³ * h * E / F}}_{\text{Z.}}}$

$\text{L = B * Pi * Phi / 720 * √}\overline{{\text{E / F}}_{\text{spec}}}$

Here mean:

epsilon

= the band stretch to be applied by the band force

Epsilon _R

= Edge expansion

Epsilon _m

= average stretch across the bandwidth

F _Z

= permissible belt tension

F _spec

= specific belt tension

H

= Strip thickness

Phi

= Twist angle

According to these calculations, the necessary free strip lengths (L) for strip widths (B) between 650 and 1980 mm for different twist angles (Phi) between the rollers (21) and (22) depend on a specific strip tension (F _spec ) and the edge edge tension (Sigma) in N / mm² and correspondingly the necessary guy lengths (L) in meters according to the diagram in Figure 6. In the present embodiment according to the invention, 6 deflections with an angle (Phi) of 30 ^o each with a bandwidth B = 1700 mm and a guy length (L) of 30 m. The diagram according to FIG. 6 shows that a specific strip tension (F _spec ) of approx. 12 N / mm 2 results for these conditions.

According to the calculation, the deflection rollers (21 or 22) are spherical. The difference in diameter (delta D) between the center (D) and the end face (D ') of a spherical roller (21, 22) corresponds approximately to the amount of the edge extension (delta) caused by the twisting of the band (30) by an angular amount (Phi) L) with constant center distance (L) of the rollers (21 or 22).

An exemplary embodiment shows the conditions for a practical embodiment as follows: - strip thickness: 0.2-0.8mm - bandwidth: 750 - 1500 mm - free guy length: approx. 30 m - roll diameter: approx. 800 mm - deflection angle per pair of rollers: 30 ^o

The increased edge tensions due to twisting are safely within the elastic range and are compensated for by a suitable choice of roller balls.

The roll bales, e.g. 3 - 4 mm in diameter with a roll diameter of 800 mm and a bale length of 1800 mm, also ensure a self-centering effect and thus exact tape running. Belt center control units are preferably provided in front of and behind the belt turning tower.

By using a belt turning tower (20) for guiding or turning the belt (30), a clear and uncomplicated device is created which can be used at any point in the system. At the same time, the height and length of the large hall (41) is reduced with considerable cost savings and the belt (30) runs in the same direction from the infeed station (1) to the outfeed station (12) of the system. Further cost savings and technical advantages result from the fact that the belt turning tower (20), in the manner of a vertical loop storage device, can have means (25) for belt length compensation and / or for maintaining a constant tension state of the belt (30).

Furthermore, the invention also opens up the possibility of arbitrarily setting the tape running direction or of deflecting the tape with a parallel offset from a first track into a second track running at a distance from it. This opens up uncomplicated possibilities of tape guidance through different Plant parts of a multi-part plant complex.

An example of this is shown purely schematically in FIG. By the plant part I a band (30c) in the strip turning tower (20) is inserted therein ^o pivoted 90 in the tape running direction, is performed after which the belt (30c) from the tower (20) out to the part of the system II. The belt (30d) runs from the system part III into the tower (20), is turned in it and continued with a parallel offset from it into the system part II. The belt (30e) runs from the plant part IV into the tower (20), is turned in it and then transported further into the plant part II. From the part of the plant V the strip (30f) runs into the tower (20) is therein pivoted in its running direction by 90 ^° and, without being turned over, continued from the tower (20) in the part of the system II.

The examples shown in FIG. 8 can be carried out individually or in groups at the same time in a correspondingly designed belt turning tower (20). They only serve to show the different possibilities of the tape guide in the tower (20), depending on its design with one or more groups of vertically spaced deflection rollers.

Claims (15)

Method for guiding a steel strip during its passage through a continuous strip treatment system having a plurality of treatment stations, the direction and / or track of the strip being set as desired and / or occasionally the strip being turned from the bottom to the top - or vice versa, characterized in that that the tape is introduced into a tape turning tower and is guided in this in a manner similar to a vertical loop storage device over vertically spaced upper and lower deflection rollers and is thereby twisted from roll to roll by an angular amount in each case, such that it is adjusted to any twisting angle between the strip inlet and the strip outlet. A method according to claim 1, characterized in that the tape is twisted by an angle of 180 ^{o in} total in such a way that after deflection around the last roll of the tape turning tower, the underside of the tape is turned towards the top of the tape at the exit when it enters the first roll, and vice versa. A method according to claim 1, characterized in that, in order to set a parallel offset between two running tracks, the belt in the belt turning tower pivots through an first group of rollers in an angle deviating from the direction of its inlet track and after passing through a straight intermediate distance corresponding to the amount of the lateral offset introduced a second group of pulleys and back into the original direction of its entry track is pivoted back. A method according to claim 1, characterized in that for compensating for a lateral displacement caused by the diverting pulleys in the belt turn (S), the tape more than 180 ^o twisted in a first group of deflection rollers by an angular amount, at an oblique angle to the strip entry axis from the last , lower roll out in a piece of straight longitudinal guide in the direction against the tape exit axis to the amount (S) of the lateral offset in a second group of deflection rollers and pivoted back by an angular amount in the coaxial to the direction of the tape entry axis (xx) tape exit axis (yy) becomes. Method according to claim 1, characterized in that crowned rollers are used to reduce the edge tensions of the belt when it is twisted between two rollers in the belt turning tower. A method according to claim 5, characterized in that the difference in diameter of a roll which determines the crowning is approximately the amount of the edge lengthening which results from the twisting of the band by an angular amount (Phi) for a given free band length (L) between a pair of rolls and causes the band edge regions to stretch corresponds. A method according to claim 1, characterized in that length differences or tension differences of the belt within the belt turning tower by changing the distances be compensated for between the lower and the upper roles interacting with them. Device for guiding a steel strip in a continuous treatment plant for steel strip, the plant having stations for treatment steps such as degreasing, annealing, galvanizing, skin-dressing, painting, checking, winding, etc., for carrying out the method according to the preceding claims, characterized by a similar one vertical loop storage belt reel tower (20) with a number of vertically spaced upper (21) and lower (22) belt deflection rollers, the rollers in the direction of travel of the belt (30) each from roll (21) to roll (22) in Angular amounts in the same direction (Phi 1 to Phi _n ) are arranged rotated relative to the tape inlet axis (xx), such that the tape (30) by wrapping a pair of rollers formed by a lower (22) and an upper (21) roller by an angle (Phi) twisted and occasionally with a sum of all twist angle amounts (Phi₁ to Phi _n ) of 180 ^o Band underside (33) to the band top (34) - and vice versa - is turned. Apparatus according to claim 8, characterized in that belt center control units are provided in front of and behind the belt turning tower (20). Apparatus according to claim 8 or 9, characterized in that the upper deflection rollers (21) of the turning device (20) have means (25) for adjusting the vertical distance (L) and / or for adjusting or keeping the tension state in the continuous state Have band (30). Device according to one or more of claims 8 to 10, characterized in that the deflection rollers (21) or (22) are spherical. Apparatus according to claim 11, characterized in that the diameter difference (delta D) between the center (D) and the end face (D ') of a spherical roller (21, 22) is approximately the amount of an angular amount due to the twisting of the band (30) (Phi) caused edge extension (delta L) of the belt (30) with unchangeable center distance (L) of the rollers (21) or (22). Device according to one or more of claims 8 to 12, characterized in that the belt turning tower (20) has two groups (20A) or (20B) of pairs of rollers (21a; 22a) or (21b; 22b) which are separated by a straight line The running distance (31) of the belt (30) at an angle (Beta) in the direction of a belt outlet axis (yy) coaxial to the belt inlet axis (xx) are connected to one another, the sum of the angular amounts (Phi₁ to Phi _n ) of the two groups (20A) and (20B) preferably add up to 180 ^o . Device according to one or more of claims 8 to 13, characterized in that the upper (21) and lower (22) rollers, as seen in the vertical projection, are assigned to one another in such a way that the side lines (28) and (29) are two a common band section (32) leading and (by the angular amount (Phi) rotated against each other rollers (21) or (22) each in the band center lines (xx) or (yy) of half the bandwidth Cut (B / 2). Method according to one or more of Claims 8 to 14, characterized in that the permissible twist angle (Phi) of the band (30) between an upper and a lower roller (21, 22) depends on the ratio of the free length (L) of the band (30 ) between these roles to determine the bandwidth (B) and the resulting edge tension (Sigma _R ) of the belt (30).

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