EP0361632B1 - Method for guiding elongate hollow cylindrical rolled material - Google Patents

Method for guiding elongate hollow cylindrical rolled material Download PDF

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Publication number
EP0361632B1
EP0361632B1 EP89250043A EP89250043A EP0361632B1 EP 0361632 B1 EP0361632 B1 EP 0361632B1 EP 89250043 A EP89250043 A EP 89250043A EP 89250043 A EP89250043 A EP 89250043A EP 0361632 B1 EP0361632 B1 EP 0361632B1
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EP
European Patent Office
Prior art keywords
rolling
rolling stock
axis
stock
during
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP89250043A
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German (de)
French (fr)
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EP0361632A2 (en
EP0361632A3 (en
Inventor
Rolf Dr.-Ing. Kümmerling
Manfred Dipl.-Ing. Bellmann
Rolf Dipl.-Ing. Pieters
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Vodafone GmbH
Original Assignee
Mannesmann AG
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Application filed by Mannesmann AG filed Critical Mannesmann AG
Publication of EP0361632A2 publication Critical patent/EP0361632A2/en
Publication of EP0361632A3 publication Critical patent/EP0361632A3/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B25/00—Mandrels for metal tube rolling mills, e.g. mandrels of the types used in the methods covered by group B21B17/00; Accessories or auxiliary means therefor ; Construction of, or alloys for, mandrels or plugs
    • B21B25/02—Guides, supports, or abutments for mandrels, e.g. carriages or steadiers; Adjusting devices for mandrels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B39/00—Arrangements for moving, supporting, or positioning work, or controlling its movement, combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
    • B21B39/14—Guiding, positioning or aligning work

Definitions

  • the invention relates to a method and a device for guiding elongated, hollow cylindrical rolling stock rotating about the longitudinal axis according to the preamble of patent claims 1 and 2.
  • a guide means arranged below the rolling axis.
  • a guide means can generally be a tube, a half-shell or, in the case of rolls with an internal tool held on the outlet side, a plurality of sleeve guide stands arranged one behind the other, in which usually three rolls lying parallel to the roll axis and adjustable in the roll axis direction are arranged.
  • the guide means is in practice set at a distance from the center of the roll so that there is play between the surface of the rolling stock and the surface of the guide means, in particular so as not to hinder the longitudinal movement of the rolling stock.
  • This game leaves transverse vibrations of the rolling stock and the inner tool which lead to increased wear of the guide means and to wall thickness irregularities. But it can also be intended as in the aforementioned DE-OS 20 32 533 a permanent system on the rolling stock, whereby the wear is increased.
  • the invention has for its object to develop a method to guide the elongated, hollow cylindrical rolling stock exactly to the center of the roll without hindering the helical feed.
  • the vibrations that occur in the usual guide system should be hampered as far as possible and thereby achieve a uniform wall thickness.
  • the proposed method can be used for all rolling mills in which the rolling stock rotates about the longitudinal axis during the rolling, that is to say the piercing mill, diagonal mill and reeler.
  • the guide means is predominantly designed as a tube or as a half-shell with corresponding slots for retracting the drive rollers.
  • the sleeve guide blocks which are mainly used for rolling with an internal tool.
  • three rollers are usually arranged parallel to the rolling axis and can be adjusted in the rolling axis direction.
  • the previously common method for guiding the rolling stock was to keep the three rollers at a predetermined distance from the surface of the rolling stock. This led to strong acceleration forces occurring during the helical feed of the rolling stock and the guide means being subjected to severe wear.
  • the two rollers arranged in a horizontal plane below the rolling axis are brought to bear on the surface of the rolling stock during the rolling process.
  • the rollers are predominantly set against the direction of gravity, so that the gravity component of the rolling stock, together with the internal tool, supports the application of the surface of the rolling stock to the rollers.
  • the third roll above the rolling axis at a predetermined distance from the surface of the rolling stock during the rolling process. This distance should be at least 20% of the outside diameter of the rolling stock. This prevents the rolling stock from striking this third role and the unwanted transverse vibrations can thereby be rekindled.
  • the two rollers lying below the rolling axis are spaced so that the straight lines from the respective axis to the center of the rolling intersect at an angle of 120 degrees. With this angle specification, the usual manufacturing and installation-related deviations of the order of magnitude of a few degrees are also to be included.
  • FIG 2 shows the rolling stock according to the inventive method, the same reference numerals as in Figure 1 were used for the same parts.
  • the two rollers 5, 5 'lying below the rolling axis have been brought into contact with the surface of the rolling stock 1, so that no play remains in the contact area between the surface of the roller 5, 5' and the rolling stock 1.
  • This system is supported by the gravity component of the rolling stock 1 and the inner tool 2 which presses on the roller 5, 5 '.
  • the roller 5' above the rolling axis is held at a predetermined distance 7 from the surface of the rolling stock 1. If there is no danger that the rolling stock 1 can jump out of the rolling line, this roller 5 ⁇ , as shown in the figure, can be pivoted into the ejection position immediately after the beginning of the rolling.

Description

Die Erfindung betrifft ein Verfahren und eine Vorrichtung zum Führen von sich um die Längsachse drehenden langgestrecktem, hohlzylindrischem Walzgut gemäß dem Gattungsbegriff der Patentansprüche 1 und 2.The invention relates to a method and a device for guiding elongated, hollow cylindrical rolling stock rotating about the longitudinal axis according to the preamble of patent claims 1 and 2.

Entsprechend dem Stand der Technik wie er sich beispielsweise aus der DE-OS 20 32 533 ergibt, wird beim Walzen, insbesondere beim Schrägwalzen, bei dem sich während des Walzvorganges das Walzgut um die Längsachse dreht, das Walzgut auf der Einlauf- bzw. auf der Auslaufseite durch ein unterhalb der Walzachse angeordnetes Führungsmittel gehalten. Ein solches Führungsmittel kann allgemein ein Rohr, eine Halbschale oder im Falle von Walzen mit einem auf der Auslaufseite gehaltenem Innenwerkzeug mehrere hintereinander angeordnete Hülsenführungsböcke sein, in denen üblicherweise drei parallel zur Walzachse liegende und in Walzachsrichtung anstellbare Rollen angeordnet sind. Bei einer solchen Dreieranordnung sind zwei Rollen in einer horizontalen Ebene liegend unterhalb der Walzachse und die dritte oberhalb der Walzachse angeordnet. Diese dritte Rolle wird nach Beendigung des Walzvorganges in Auswerfstellung geschwenkt, damit das fertiggewalzte Gut zusammen mit dem Innenwerkzeug aus der Walzlinie entfernt werden kann. Während des Walzvorganges wird das Führungsmittel in der Praxis abstandsmäßig so zum Walzmittelpunkt eingestellt, daß zwischen der Oberfläche des Walzgutes und der Oberfläche des Führungsmittels sich ein Spiel ergibt, um insbesondere die Längsbewegung des Walzgutes nicht zu behindern. Dieses Spiel läßt aber transversale Schwingungen des Walzgutes und des Innenwerkzeuges zu, die zu einem erhöhten Verschleiß des Führungsmittels und zu Wanddickenungleichmäßigkeiten führen. Es kann aber auch wie bei der genannten DE-OS 20 32 533 eine ständige Anlage am Walzgut beabsichtigt sein, wodurch der Verschleiß noch vergrößert wird.According to the state of the art as it results for example from DE-OS 20 32 533, during rolling, in particular with cross-rolling, in which the rolling stock rotates about the longitudinal axis during the rolling process, the rolling stock is on the inlet or on the Exit side held by a guide means arranged below the rolling axis. Such a guide means can generally be a tube, a half-shell or, in the case of rolls with an internal tool held on the outlet side, a plurality of sleeve guide stands arranged one behind the other, in which usually three rolls lying parallel to the roll axis and adjustable in the roll axis direction are arranged. In such a three-way arrangement, two rollers are arranged in a horizontal plane below the rolling axis and the third above the rolling axis. This third roll is pivoted into the ejection position after the rolling process has ended, so that the finished rolled material can be removed from the rolling line together with the internal tool. During the rolling process, the guide means is in practice set at a distance from the center of the roll so that there is play between the surface of the rolling stock and the surface of the guide means, in particular so as not to hinder the longitudinal movement of the rolling stock. This game leaves transverse vibrations of the rolling stock and the inner tool which lead to increased wear of the guide means and to wall thickness irregularities. But it can also be intended as in the aforementioned DE-OS 20 32 533 a permanent system on the rolling stock, whereby the wear is increased.

Der Erfindung liegt die Aufgabe zugrunde, ein Verfahren zu entwickeln,
um das langgestreckte, hohlzylindrische Walzgut genau auf Walzmitte zu führen, ohne dabei den wendelförmigen Vorschub zu behindern. Die beim üblichen Führungssystem auftretenden Schwingungen sollen möglichst weitgehend behindert und dadurch eine gleichmäßige Wanddicke erzielt werden.The invention has for its object to develop a method
to guide the elongated, hollow cylindrical rolling stock exactly to the center of the roll without hindering the helical feed. The vibrations that occur in the usual guide system should be hampered as far as possible and thereby achieve a uniform wall thickness.

Diese Aufgabe wird durch die kennzeichnenden Merkmale der Patentansprüche 1 und 2 gelöst.This object is achieved by the characterizing features of claims 1 and 2.

Die direkte Anlage eines parallel zur Walzachse liegenden Oberflächenbereiches des Führungsmittels an die Oberfläche des Walzgutes während des Walzvorganges minimiert die ansonsten bei einem mit Spiel angestellten Führungsmittel auftretenden Beschleunigungskräfte und damit die Frequenz und die Amplitude des Schlages. Durch den Wegfall der Luftspaltwege zwischen der Oberfläche des Walzgutes und des Führungsmittels wird die kinetische Energie nahezu zu Null gemacht. Die Führung wird hör- und sichtbar besser. Mit diesem erfindungsgemäßen Verfahren ist es möglich, die Walzwerksleistung durch höhere zulässige Drehzahlen zu steigern, den Verschleiß der Führungsmittel zu vermindern und die Maßhaltigkeit, insbesondere die Wanddicke des Walzgutes zu verbessern.The direct contact of a surface area of the guide means lying parallel to the rolling axis to the surface of the rolling stock during the rolling process minimizes the acceleration forces that otherwise occur with a guide means that is engaged with play and thus the frequency and the amplitude of the impact. By eliminating the air gap paths between the surface of the rolling stock and the guide means, the kinetic energy is made almost zero. The guidance becomes audible and visibly better. With this method according to the invention, it is possible to increase the rolling mill performance by higher permissible speeds, to reduce the wear of the guide means and to improve the dimensional accuracy, in particular the wall thickness, of the rolling stock.

Das vorgeschlagene Verfahren ist anwendbar für alle Walzwerke, bei denen das Walzgut sich während des Walzens um die Längsachse dreht, d. h. Lochwalzwerk Schrägwalzfwerk und Reeler. Bei den Walzverfahren ohne Innenwerkzeug ist das Führungsmittel überwiegend als Rohr oder als Halbschale mit entsprechenden Schlitzen zum Einfahren der Treibrollen ausgebildet.The proposed method can be used for all rolling mills in which the rolling stock rotates about the longitudinal axis during the rolling, that is to say the piercing mill, diagonal mill and reeler. In the rolling process without an internal tool, the guide means is predominantly designed as a tube or as a half-shell with corresponding slots for retracting the drive rollers.

Anders sieht es bei den Hülsenführungsböcken aus, die hauptsächlich für das Walzen mit einem Innenwerkzeug verwendet werden. In diesen Böcken sind üblicherweise drei parallel zur Walzachse liegende Rollen angeordnet, die in Walzachsrichtung anstellbar sind. Das bisher übliche Verfahren zum Führen des Walzgutes bestand darin, die drei Rollen in einem vorgegebenen Abstand zur Oberfläche des Walzgutes zu halten. Dies führte dazu, daß starke Beschleunigungskräfte während des wendelförmigen Vorschubes des Walzgutes auftraten und das Führungsmittel einem starken Verschleiß unterworfen wurde. Bei dem erfindungsgemäßen Verfahren werden die zwei in einer horizontalen Ebene liegenden unterhalb der Walzachse angeordneten Rollen während des Walzvorganges an die Oberfläche des Walzgutes zur Anlage gebracht. Dabei ist erfindungswesentlich, daß die Anstellung der Rollen überwiegend entgegen der Schwerkraftrichtung erfolgt, so daß die Schwerkraftkomponente des Walzgutes zusammen mit dem Innenwerkzeug das Anlegen der Oberfläche des Walzgutes an die Rollen unterstützt. Damit das Walzgut im Störungsfall nicht aus der Walzlinie springen kann, wird weiterbildend vorgeschlagen, die dritte oberhalb der Walzachse liegende Rolle während des Walzvorganges in einem vorgegebenen Abstand zur Oberfläche des Walzgutes zu halten. Dieser Abstand soll dabei mindestens 20 % des Walzgutaußendurchmessers betragen. Damit wird verhindert, daß das Walzgut an diese dritte Rolle schlägt und dadurch wieder die nicht gewünschten transversalen Schwingungen angefacht werden können. Die zwei unterhalb der Walzachse liegenden Rollen werden abstandsmäßig so angeordnet, daß sich die von der jeweiligen Achse zum Walzmittelpunkt gedachten Geraden in einem Winkel von 120 Grad schneiden. Mit dieser Winkelangabe sollen die üblichen herstellungs- und einbaubedingten Abweichungen in der Größenordnung von einigen Graden mit erfaßt sein.The situation is different with the sleeve guide blocks, which are mainly used for rolling with an internal tool. In these trestles, three rollers are usually arranged parallel to the rolling axis and can be adjusted in the rolling axis direction. The previously common method for guiding the rolling stock was to keep the three rollers at a predetermined distance from the surface of the rolling stock. This led to strong acceleration forces occurring during the helical feed of the rolling stock and the guide means being subjected to severe wear. In the method according to the invention, the two rollers arranged in a horizontal plane below the rolling axis are brought to bear on the surface of the rolling stock during the rolling process. It is essential to the invention that the rollers are predominantly set against the direction of gravity, so that the gravity component of the rolling stock, together with the internal tool, supports the application of the surface of the rolling stock to the rollers. In order to prevent the rolling stock from jumping out of the rolling line in the event of a fault, it is proposed to keep the third roll above the rolling axis at a predetermined distance from the surface of the rolling stock during the rolling process. This distance should be at least 20% of the outside diameter of the rolling stock. This prevents the rolling stock from striking this third role and the unwanted transverse vibrations can thereby be rekindled. The two rollers lying below the rolling axis are spaced so that the straight lines from the respective axis to the center of the rolling intersect at an angle of 120 degrees. With this angle specification, the usual manufacturing and installation-related deviations of the order of magnitude of a few degrees are also to be included.

In der Zeichnung wird das erfindungsgemäße Verfahren näher erläutert.The method according to the invention is explained in more detail in the drawing.

Es zeigen:

Figur 1
die Walzgutführung entsprechend dem bekannten Verfahren
Figur 2
die erfindungsgemäße Walzgutführung
In Figur 1 ist die Walzgutführung entsprechend dem bisher bekannten Verfahren dargestellt. In diesem Beispiel wird das Walzgut 1 mit einem Innenwerkzeug 2, z. B. Dorn oder Stange, gewalzt. Während des Walzens dreht sich das Walzgut 1 zusammen mit der Stange 2 um die Längsachse 3, wie durch den Pfeil 4 angedeutet. Die Längsachse 3 ist hier zugleich auch die Walzachse. Die drei Rollen 5, 5′, 5˝ sind in einem hier nicht dargestellten Hülsenführungsbock angeordnet und in Walzachsrichtung anstellbar. Die Anstellung der Rollen erfolgt in der Weise, daß zwischen der Oberfläche der Rollen 5, 5′, 5˝ und des Walzgutes 1 ein Spiel 6 verbleibt. Nach dem Walzen kann die oberhalb der Walzachse liegende Rolle 5˝ in Auswerfstellung, hier gestrichelt dargestellt, geschwenkt werden, damit das Walzgut 1 zusammen mit dem Innenwerkzeug 2 aus der Walzlinie entfernt werden kann.Show it:
Figure 1
the rolling stock management according to the known method
Figure 2
the rolling stock guide according to the invention
In Figure 1, the rolling stock is shown according to the previously known method. In this example, the rolling stock 1 with an inner tool 2, z. B. mandrel or rod, rolled. During rolling, the rolling stock 1 rotates together with the rod 2 about the longitudinal axis 3, as indicated by the arrow 4. The longitudinal axis 3 is also the rolling axis here. The three rollers 5, 5 ', 5˝ are arranged in a sleeve guide block, not shown here, and can be adjusted in the rolling axis direction. The employment of the roles takes place in such a way that a game 6 remains between the surface of the roles 5, 5 ', 5˝ and the rolling stock 1. After rolling, the roller 5˝ above the rolling axis can be pivoted in the ejection position, shown here in broken lines, so that the rolling stock 1 can be removed from the rolling line together with the inner tool 2.

Figur 2 zeigt die Walzgutführung gemäß dem erfindungsgemäßen Verfahren, wobei für gleiche Teile gleiche Bezugszeichen wie in Figur 1 verwendet wurden. Während des Walzvorganges sind die zwei unterhalb der Walzachse liegenden Rollen 5, 5′ zur Anlage an die Oberfläche des Walzgutes 1 gebracht worden, so daß im Berührungsbereich zwischen der Oberfläche der Rolle 5, 5′ und des Walzgutes 1 kein Spiel verbleibt. Unterstützt wird diese Anlage durch die auf die Rolle 5, 5′ drückende Schwerkraftkomponente des Walzgutes 1 und des Innenwerkzeuges 2. Aus Sicherheitsgründen wird die oberhalb der Walzachse liegende Rolle 5˝ in einem vorgegebenen Abstand 7 zur Oberfläche des Walzgutes 1 gehalten. Falls keine Gefahr besteht, daß das Walzgut 1 aus der Walzlinie springen kann, kann diese Rolle 5˝ ebenso wie in Figur dargestellt sofort nach Walzbeginn in Auswerfstellung geschwenkt werden.Figure 2 shows the rolling stock according to the inventive method, the same reference numerals as in Figure 1 were used for the same parts. During the rolling process, the two rollers 5, 5 'lying below the rolling axis have been brought into contact with the surface of the rolling stock 1, so that no play remains in the contact area between the surface of the roller 5, 5' and the rolling stock 1. This system is supported by the gravity component of the rolling stock 1 and the inner tool 2 which presses on the roller 5, 5 '. For safety reasons, the roller 5' above the rolling axis is held at a predetermined distance 7 from the surface of the rolling stock 1. If there is no danger that the rolling stock 1 can jump out of the rolling line, this roller 5˝, as shown in the figure, can be pivoted into the ejection position immediately after the beginning of the rolling.

Claims (3)

  1. A method of guiding elongate hollow-cylindrical rolling stock (1) rotating about the longitudinal axis (3) by means of guidance means which are arranged above and below the rolling stock (1) parallel to the rolling axis and are adjustable in the direction of the rolling axis, characterised in that during the rolling operation for the guidance of the hollow-cylindrical rolling stock (1) exactly on the rolling centre at least one of the guidance means arranged below the rolling stock (1) is brought predominantly contrary to the direction of gravity into abutment against the rolling stock (1), with the guidance means arranged above being in the lifted-off position.
  2. Apparatus for carrying out the method according to claim 1, in which respect provided above and below the elongate hollow-cylindrical rolling stock (1) are rollers (5, 5', 5'') which guide this and lie parallel to the rolling axis and are adjustable in the direction of the rolling axis, characterised in that during the rolling operation for the guidance of the hollow-cylindrical rolling stock exactly on the rolling centre a constantly varying region of the outer surface of two rollers (5, 5') arranged in a horizontal plane at a spacing from one another and lying below the rolling axis is brought into abutment, and in that the roller (5'') arranged above the rolling axis is kept at a predetermined distance from the surface of the rolling stock during the rolling operation.
  3. Apparatus according to claim 2, characterised in that the distance of the surface of the roller from the surface of the rolling stock amounts to at least 20% of the outside diameter of the rolling stock.
EP89250043A 1988-09-28 1989-09-21 Method for guiding elongate hollow cylindrical rolled material Expired - Lifetime EP0361632B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3833375 1988-09-28
DE3833375A DE3833375C1 (en) 1988-09-28 1988-09-28

Publications (3)

Publication Number Publication Date
EP0361632A2 EP0361632A2 (en) 1990-04-04
EP0361632A3 EP0361632A3 (en) 1991-03-20
EP0361632B1 true EP0361632B1 (en) 1993-12-29

Family

ID=6364142

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89250043A Expired - Lifetime EP0361632B1 (en) 1988-09-28 1989-09-21 Method for guiding elongate hollow cylindrical rolled material

Country Status (3)

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EP (1) EP0361632B1 (en)
DE (2) DE3833375C1 (en)
ES (1) ES2047658T3 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19606361C2 (en) * 1996-02-12 1998-02-26 Mannesmann Ag Device for guiding a billet
DE19714300A1 (en) * 1997-03-24 1998-10-01 Mannesmann Ag Device for guiding a billet
DE102008028348B4 (en) * 2008-06-07 2010-05-27 Sms Meer Gmbh Device for guiding rotating mandrel bars and hollow blocks in the area of cross rolling mills

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1762427A (en) * 1928-07-12 1930-06-10 Ralph C Stiefel Tube-rotating apparatus
DE2032533A1 (en) * 1970-07-01 1972-01-13 Fa. Friedrich Kocks, 4000 Düsseldorf Cross rolling mill - for workpiece and mandrel alignment and guiding
JPS5772708A (en) * 1980-10-24 1982-05-07 Nippon Kokan Kk <Nkk> Front and back roller guide for skew rolling mill
DE8607191U1 (en) * 1986-03-13 1986-04-24 Mannesmann AG, 40213 Düsseldorf Device for centering and guiding a mandrel bar and a hollow body

Also Published As

Publication number Publication date
EP0361632A2 (en) 1990-04-04
ES2047658T3 (en) 1994-03-01
DE58906556D1 (en) 1994-02-10
DE3833375C1 (en) 1989-05-18
EP0361632A3 (en) 1991-03-20

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