EP0567203A2 - Method for influencing the friction between roll and rolling stock, in particular for the rolling of pipes - Google Patents

Method for influencing the friction between roll and rolling stock, in particular for the rolling of pipes Download PDF

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Publication number
EP0567203A2
EP0567203A2 EP93250069A EP93250069A EP0567203A2 EP 0567203 A2 EP0567203 A2 EP 0567203A2 EP 93250069 A EP93250069 A EP 93250069A EP 93250069 A EP93250069 A EP 93250069A EP 0567203 A2 EP0567203 A2 EP 0567203A2
Authority
EP
European Patent Office
Prior art keywords
rolling
friction
roll
texturing
influencing
Prior art date
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.)
Withdrawn
Application number
EP93250069A
Other languages
German (de)
French (fr)
Other versions
EP0567203A3 (en
Inventor
Peter Thieven
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vodafone GmbH
Original Assignee
Mannesmann AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Mannesmann AG filed Critical Mannesmann AG
Publication of EP0567203A2 publication Critical patent/EP0567203A2/en
Publication of EP0567203A3 publication Critical patent/EP0567203A3/xx
Withdrawn legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C26/00—Coating not provided for in groups C23C2/00 - C23C24/00
    • C23C26/02—Coating not provided for in groups C23C2/00 - C23C24/00 applying molten material to the substrate
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B17/00—Tube-rolling by rollers of which the axes are arranged essentially perpendicular to the axis of the work, e.g. "axial" tube-rolling
    • B21B17/14—Tube-rolling by rollers of which the axes are arranged essentially perpendicular to the axis of the work, e.g. "axial" tube-rolling without mandrel, e.g. stretch-reducing mills
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B27/00—Rolls, roll alloys or roll fabrication; Lubricating, cooling or heating rolls while in use
    • B21B27/005—Rolls with a roughened or textured surface; Methods for making same
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/38—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for roll bodies

Definitions

  • the invention relates to a method for influencing the friction between the roll and the rolling stock, in particular when rolling pipes in stretch-reducing rolling mills.
  • the present invention is based on the proposal to propose a method for influencing the friction between the roll and the rolling stock, with which particularly favorable material flow conditions in the roll gap with regard to elongation and spreading of the rolling stock can be adjusted.
  • a method is proposed according to the invention, which is characterized by the generation of an anisotropic coefficient of friction which is higher in the rolling direction than transverse to the rolling direction.
  • the invention provides for the microstructure of the roll surface to be prepared in such a way that the friction value is high in the rolling direction and as low as possible in the transverse direction.
  • the rolling stock experiences a desired spreading, which helps to avoid rolling errors, for example the formation of inner polygons.
  • the texturing of the roll surface be carried out by laser or electron beam treatment. Hoofs of the surface of the rollers are made with tiny oval depressions or channels with a fixed orientation, so that the coefficient of friction becomes direction-dependent.
  • the texturing of the roll surface takes place by local melting of the call and directional solidification of the crystallites.
  • the direction of the crystallites determines the size of the coefficient of friction, whereby there is no need to roughen the work roll surface.
  • the texturing of the roll surface is carried out by vapor deposition or galvanic coating with controlled alignment of the surface layer.
  • All of the proposed measures for influencing the coefficient of friction are suitable for reducing the number of control and regulating devices for controlling the spread and / or for increasing the generation program of a system, e.g. B. because you can then roll dimensions that could not be generated due to the resulting polygon formation.
  • the invention can be used universally, for example also for rolling flat products.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Reduction Rolling/Reduction Stand/Operation Of Reduction Machine (AREA)

Abstract

The invention relates to a method for influencing the friction between roll and rolling stock, especially when rolling tubes in stretch reducing mills. In order to be able to establish particularly favourable material flow conditions in the roll gap as regards the lengthening and widening of the rolling stock, it is proposed that an anisotropic friction coefficient - higher in the direction of rolling than transversely to the direction of rolling be produced.

Description

Die Erfindung betrifft ein Verfahren zur Beeinflussung der Reibung zwischen Walze und Walzgut, insbesondere beim Walzen von Rohren in Streckreduzierwalzwerken.The invention relates to a method for influencing the friction between the roll and the rolling stock, in particular when rolling pipes in stretch-reducing rolling mills.

Es ist insbesondere bei Streckreduzierwalzwerken bekannt, daß der Reibungskoeffizient zwischen Walze und Walzgut eine große Bedeutung für das maßhaltige Walzen im Walzwerk hat. Bei Streckreduzierwalzwerken sind hohe Reibungskoeffizienten dort von Bedeutung, wo in Längsrichtung des Walzgutes erheblicher Zug aufzubauen ist. Mit verschiedenen Mitteln und Maßnahmen hat man deshalb versucht, die Reibung im Walzspalt zu beeinflussen. So ist vorgeschlagen worden, unterschiedliche Werkstoffe für die Walzen einzusetzen. Es ist weiterhin vorgeschlagen worden, die Walzenarbeitsflächen durch Sandstrahlen oder ähnliche mechanische Maßnahmen aufzurauhen oder durch Einbringen von Nuten oder Wulsten quer zur Walzrichtung in die Arbeitsflächen der Walzen eine Steigerung des Reibungskoeffizienten in Walzrichtung zu erreichen.It is known, in particular in the case of stretch-reducing rolling mills, that the coefficient of friction between the roll and the rolling stock is of great importance for dimensionally stable rolling in the rolling mill. In the case of stretch-reducing rolling mills, high coefficients of friction are of importance where considerable tension has to be built up in the longitudinal direction of the rolling stock. Various means and measures have therefore been used to influence the friction in the roll gap. It has been proposed to use different materials for the rollers. It has also been proposed to roughen the roller work surfaces by sandblasting or similar mechanical measures, or to increase the coefficient of friction in the rolling direction by introducing grooves or beads into the work surfaces of the rollers transversely to the rolling direction.

Während unterschiedliche Walzenwerkstoffe nur bei aufeianderfolgenden Walzgerüsten zum Einsatz kamen und der Verminderung der sogenannten verdickten Enden dienten, ist das Rufrauhen der Walzenarbeitsfläche durch Sandstrahlen auf Dauer nicht wirkungsvoll, weil die so erzeugte Rauhigkeit nach relativ kurzer Zeit abgeschlissen ist. Das Einbringen von Wulsten oder Nuten quer zur Walzrichtung beschädigte sowohl die Hußen- wie auch die Innenoberfläche des Rohres, vor allem bei warmgewalzten Rohren, die ohne Innenwerkzeug hergestellt werden.While different roller materials were only used in successive roll stands and served to reduce the so-called thickened ends, the roughening of the roller work surface by sandblasting is not effective in the long run because the roughness generated in this way is removed after a relatively short time. The introduction of beads or grooves transverse to the rolling direction damaged both the shell and the inner surface of the tube, especially in the case of hot-rolled tubes which are produced without an internal tool.

Auch der Vorschlag der DE 37 01 154 C2, der Kühlflussigkeit aller oder einzelner einlaufseitig angeordneter Walzgerüste Zusätze beizufügen, die die Reibung zwischen Walze und Walzgut erhöhen, bringt nicht den nötigen Erfolg. Alle vorstehend beschriebenen Lösungen dienten der Beeinflussung des Reibwertes mit dem Ziel, die Zugbedingungen des Walzwerkes im Einlauf- bzw. Auslauf zu verbessern. Keine der Lösungen ist geeignet, die beim Warmwalzen, insbesondere von Rohren auftretenden Walzfehler zu vermeiden, die dadurch entstehen, daß der optimale Stofffluß des Walzgutes durch die Reibung behindert wird. So sind Innenpoligonbildungen bei Rohren, die auf Streckreduzierwalzwerken hergestellt sind, auf derartige reibungsbedingte Fehler zurückzuführen, weil die Reibbedingungen in und quer zur Walzrichtung nicht den erforderlichen Fließbedingungen im Walzspalt angepaßt sind.The proposal of DE 37 01 154 C2 to add additives to the cooling liquid of all or individual roll stands arranged on the inlet side, which increase the friction between the roll and the rolling stock, does not bring the necessary success. All of the solutions described above served to influence the coefficient of friction with the aim of improving the tensile conditions of the rolling mill in the inlet and outlet. None of the solutions is suitable for avoiding the rolling errors which occur during hot rolling, in particular of pipes, which arise from the fact that the optimal material flow of the rolling stock is impeded by the friction. For example, internal poligonal formations in pipes which are produced on stretch-reducing rolling mills can be attributed to such friction-related errors because the friction conditions in and across the rolling direction are not adapted to the required flow conditions in the roll gap.

Ausgehend von der vorstehend geschilderten Problematik und dem bekannten Stand der Technik liegt der vorliegenden Erfindung die Rutgabe zugrunde, ein Verfahren zur Beeinflussung der Reibung zwischen Walze und Walzgut vorzuschlagen, mit dem besonders günstige Stoffflußbedingungen im Walzspalt hinsichtlich Längung und Breitung des Walzgutes eingestellt werden können.Based on the problems described above and the known prior art, the present invention is based on the proposal to propose a method for influencing the friction between the roll and the rolling stock, with which particularly favorable material flow conditions in the roll gap with regard to elongation and spreading of the rolling stock can be adjusted.

Zur Lösung der Aufgabe wird erfindungsgemäß ein Verfahren vorgeschlagen, das gekennzeichnet ist durch die Erzeugung eines anisotropen Reibungsbeiwertes, der in Walzrichtung höher als quer zur Walzrichtung ist.To achieve the object, a method is proposed according to the invention, which is characterized by the generation of an anisotropic coefficient of friction which is higher in the rolling direction than transverse to the rolling direction.

In einer günstigen Ausgestaltung der Erfindung wird vorgeschlagen, daß die Erhöhung des Reibungsbeiwertes durch Texturierung der wirksamen Walzenoberfläche quer zur Walzrichtung erfolgt.In a favorable embodiment of the invention, it is proposed that the increase in the coefficient of friction takes place by texturing the effective roll surface transverse to the rolling direction.

Durch die Erfindung ist vorgesehen, die Walzenoberfläche in ihrer Mikrostruktur so aufzubereiten, daß der Reibungswert in Walzrichtung hoch und in Querrichtung möglichst niedrig ist. Dadurch erfährt das Walzgut eine gewünschte Breitung, die der Vermeidung von Walzfehlern, beispielsweise Innenpolygonbildung zugute kommt.The invention provides for the microstructure of the roll surface to be prepared in such a way that the friction value is high in the rolling direction and as low as possible in the transverse direction. As a result, the rolling stock experiences a desired spreading, which helps to avoid rolling errors, for example the formation of inner polygons.

In einer Ausgestaltung der Erfindung wird vorgeschlagen, daß die Texturierung der Walzenoberfläche durch Laser- oder Elektronenstrahlbehandlung erfolgt. Huf der Oberfläche der Walzen werden winzige ovale Vertiefungen oder Rinnen mit festgelegter Ausrichtung aufgebracht, so daß der Reibbeiwert richtungsabhängig wird.In one embodiment of the invention, it is proposed that the texturing of the roll surface be carried out by laser or electron beam treatment. Hoofs of the surface of the rollers are made with tiny oval depressions or channels with a fixed orientation, so that the coefficient of friction becomes direction-dependent.

In einer weiteren Ausgestaltung der Erfindung ist vorgesehen, daß die Texturierung der Walzenoberfläche durch örtliches Rufschmelzen und gerichtetes Erstarren der Kristallite erfolgt. Die Richtung der Kristallite ist bestimmend für die Größe des Reibungsbeiwertes, wobei kein Aufrauhen der Arbeitswalzenoberfläche erfolgen muß.In a further embodiment of the invention, it is provided that the texturing of the roll surface takes place by local melting of the call and directional solidification of the crystallites. The direction of the crystallites determines the size of the coefficient of friction, whereby there is no need to roughen the work roll surface.

Schließlich ist vorgesehen, daß die Texturierung der Walzenoberfläche durch Bedampfen oder galvanisches überziehen mit geregelter Ausrichtung der Oberflächenschicht erfolgt.Finally, it is provided that the texturing of the roll surface is carried out by vapor deposition or galvanic coating with controlled alignment of the surface layer.

Alle vorgeschlagenen Maßnahmen zur Beeinflussung des Reibbeiwertes sind geeignet, den Umtang der Steuer- und Regeleinrichtungen zur Kontrolle der Breitung zu verringern und/oder das Erzeugungsprogramm einer Anlage zu vergrößern, z. B. weil man dann Abmessungen walzen kann, die bislang infolge der sich ergebenden Polygonbildung nicht erzeugt werden konnten.All of the proposed measures for influencing the coefficient of friction are suitable for reducing the number of control and regulating devices for controlling the spread and / or for increasing the generation program of a system, e.g. B. because you can then roll dimensions that could not be generated due to the resulting polygon formation.

Die Erfindung ist universell anwendbar, beispielsweise auch zum Walzen von Flachprodukten.The invention can be used universally, for example also for rolling flat products.

Claims (5)

Verfahren zur Beeinflussung der Reibung zwischen Walze und Walzgut, insbesondere beim Walzen von Rohren in Streckreduzierwalzwerken,
gekennzeichnet durch
die Erzeugung eines anisotropen Reibungsbeiwertes, der in Walzrichtung höher als quer zur Walzrichtung ist.Process for influencing the friction between the roll and the rolling stock, in particular when rolling pipes in stretch-reducing rolling mills,
marked by
the generation of an anisotropic coefficient of friction which is higher in the rolling direction than transverse to the rolling direction. Verfahren nach Anspruch 1,
dadurch gekennzeichnet,
daß die Erhöhung des Reibungsbeiwertes durch Texturierung der wirksamen Walzenoberfläche quer zur Walzrichtung erfolgt.Method according to claim 1,
characterized,
that the increase in the coefficient of friction takes place by texturing the effective roll surface transverse to the rolling direction. Verfahren nach Anspruch 1 und 2,
dadurch gekennzeichnet,
daß die Texturierung der Walzenoberfläche durch Laser- oder Elektronenstrahlbehandlung erfolgt.Method according to claims 1 and 2,
characterized,
that the texturing of the roller surface is carried out by laser or electron beam treatment. Verfahren nach Anspruch 1 und 2,
dadurch gekennzeichnet,
daß die Texturierung der Walzenoberfläche durch örtliches Rufschmelzen und gerichtetes Erstarren der Kristallite erfolgt.Method according to claims 1 and 2,
characterized,
that the texturing of the roll surface takes place through local meltdown and directional solidification of the crystallites. Verfahren nach Anspruch 1 und 2,
dadurch gekennzeichnet,
daß die Texturierung der Walzenoberfläche durch Bedampfen oder galvanisches Überziehen mit geregelter Ausrichtung der Oberflächenschicht erfolgt.Method according to claims 1 and 2,
characterized,
that the texturing of the roller surface is carried out by vapor deposition or galvanic coating with a controlled alignment of the surface layer.
EP93250069A 1992-04-22 1993-03-02 Method for influencing the friction between roll and rolling stock, in particular for the rolling of pipes Withdrawn EP0567203A2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4213667 1992-04-22
DE4213667 1992-04-22

Publications (2)

Publication Number Publication Date
EP0567203A2 true EP0567203A2 (en) 1993-10-27
EP0567203A3 EP0567203A3 (en) 1994-03-23

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EP93250069A Withdrawn EP0567203A2 (en) 1992-04-22 1993-03-02 Method for influencing the friction between roll and rolling stock, in particular for the rolling of pipes

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2876312A1 (en) 2013-11-25 2015-05-27 HILTI Aktiengesellschaft Expansion anchor with anisotropic friction coefficients

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2248092A1 (en) * 1973-10-17 1975-05-16 Alusuisse
SU770583A1 (en) * 1978-12-05 1980-10-15 Nizhnedneprovskij Truboprokatn Roll for longitudinal rolling of tubes
SU778836A1 (en) * 1978-07-10 1980-11-20 Институт черной металлургии Method of working workroll set
FR2476524A1 (en) * 1980-02-27 1981-08-28 Sumitomo Metal Ind PROCESS FOR WORKING THE SURFACE OF A COLD ROLLING ROLLER
SU1215777A1 (en) * 1984-09-29 1986-03-07 Днепропетровский Ордена Трудового Красного Знамени Металлургический Институт Им.Л.И.Брежнева Roll for lengthwise tube rolling

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2248092A1 (en) * 1973-10-17 1975-05-16 Alusuisse
SU778836A1 (en) * 1978-07-10 1980-11-20 Институт черной металлургии Method of working workroll set
SU770583A1 (en) * 1978-12-05 1980-10-15 Nizhnedneprovskij Truboprokatn Roll for longitudinal rolling of tubes
FR2476524A1 (en) * 1980-02-27 1981-08-28 Sumitomo Metal Ind PROCESS FOR WORKING THE SURFACE OF A COLD ROLLING ROLLER
SU1215777A1 (en) * 1984-09-29 1986-03-07 Днепропетровский Ордена Трудового Красного Знамени Металлургический Институт Им.Л.И.Брежнева Roll for lengthwise tube rolling

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
METALLURGIST Bd. 28, Nr. 3/4, März 1984, NEW YORK US Seiten 108 - 111 V. I. ANDREEV ET AL. 'Spark machining of the working surfaces of a tube-mill rolls' *
SOVIET INVENTIONS ILLUSTRATED Section Ch, Week 8643, 6. November 1986 Derwent Publications Ltd., London, GB; Class M21, AN 86-283631/43 & SU-A-1 215 777 (DNEPR METAL INST) 7. März 1986 *
SOVIET INVENTIONS ILLUSTRATED Section Ch, Week D30, 2. September 1981 Derwent Publications Ltd., London, GB; Class M21, AN 54641 D/30 & SU-A-778 836 (FERROUS METALLURGY INST) 20. November 1980 *
SOVIET INVENTIONS ILLUSTRATED Section PQ, Week D26, 5. August 1981 Derwent Publications Ltd., London, GB; Class P51, AN 47358 D/26 & SU-A-770 583 (NIZHNEDNEPROVSK PIP) 15. Oktober 1980 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2876312A1 (en) 2013-11-25 2015-05-27 HILTI Aktiengesellschaft Expansion anchor with anisotropic friction coefficients
WO2015075022A1 (en) * 2013-11-25 2015-05-28 Hilti Aktiengesellschaft Expanding anchor having an anisotropic coefficient of friction
US9970465B2 (en) 2013-11-25 2018-05-15 Hilti Aktiengesellschaft Expansion anchor with an anisotropic coefficient of friction

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Publication number Publication date
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