EP0442864A1 - Method and arrangement for rolling of rods and wires - Google Patents

Method and arrangement for rolling of rods and wires Download PDF

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Publication number
EP0442864A1
EP0442864A1 EP91890010A EP91890010A EP0442864A1 EP 0442864 A1 EP0442864 A1 EP 0442864A1 EP 91890010 A EP91890010 A EP 91890010A EP 91890010 A EP91890010 A EP 91890010A EP 0442864 A1 EP0442864 A1 EP 0442864A1
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EP
European Patent Office
Prior art keywords
rolling
temperature
rolling stock
cross
sectional area
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EP91890010A
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German (de)
French (fr)
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EP0442864B1 (en
Inventor
Hans Dipl.-Ing. Lösch
Franz Rischka
Johann Eilmer
Karl Strahlhofer
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Voestalpine Boehler Edelstahl GmbH
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Boehler GmbH
Boehler Edelstahl GmbH
Boehler GmbH Germany
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/16—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling wire rods, bars, merchant bars, rounds wire or material of like small cross-section
    • B21B1/18—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling wire rods, bars, merchant bars, rounds wire or material of like small cross-section in a continuous process
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B3/00—Rolling materials of special alloys so far as the composition of the alloy requires or permits special rolling methods or sequences ; Rolling of aluminium, copper, zinc or other non-ferrous metals
    • B21B3/02—Rolling special iron alloys, e.g. stainless steel
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
    • B21B45/004—Heating the product
    • 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
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/06—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of rods or wires
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
    • B21B1/16—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling wire rods, bars, merchant bars, rounds wire or material of like small cross-section
    • B21B1/166—Rolling wire into sections or flat ribbons
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B2203/00—Auxiliary arrangements, devices or methods in combination with rolling mills or rolling methods
    • B21B2203/06—Cassettes

Definitions

  • the invention relates to a method and an arrangement for rolling wire and rod material made of metallic materials, wherein the rolling stock is given a reduction in the cross-sectional area of at least 50%.
  • Rolling or drawing processes are used throughout for the production of wire and rod material, raw material with a large cross-sectional area or with a large diameter, in particular over 10 mm, by rolling at high temperatures, preferably over 1000 ° C., and raw material with a small diameter, in particular less than 5 mm, by drawing, usually in several steps, at room temperature, optionally with soft annealing treatments between the drawing steps.
  • wire with a small cross-section is produced by using continuous isothermal rolling in a roll train equipped with heated rolls, followed by a subsequent drawing without intermediate annealing.
  • the preheating and rolling temperature is chosen high in order to avoid material hardening or to save intermediate annealing operations. Disadvantages here are oxidation of the surface, a coarse microstructure and the hardening of higher carbon alloys with rapid cooling from the rolling heat.
  • the rolling stock is rolled in at least two steps, the last step involving a deformation of at least 50% with at least two rolling steps at a temperature which is close to, but above the AR3 temperature of the alloy, is carried out.
  • Disadvantages here are oxidation of the primary material during heating and increased roller wear, as well as structural inhomogeneities over the cross section of the workpiece due to the formation of surface martensite during intermediate cooling.
  • FR-PS-2 579 116 a method is known for the continuous production of metallic profiles, in which a wire or rod material is removed from the storage device and straightened in a roller straightening machine, after which the rolled material is first conductively preheated and then inductively final heated and with is deformed several rolling steps.
  • This process is complex because surface cleaning of the rolling stock, for example by brushing, may be necessary before the conductive heating.
  • unevenness in the surface and therefore punctiform introduction of current into the primary material in this stoving point or areas which are brought to high temperature for a short time and thus harden can be formed.
  • Better heating conditions are to be achieved by means of complex inductive final heating.
  • the straightening process creates in the primary material in places, especially in the near-surface zone of the primary material, plastic deformations or solidified points, which can cause inhomogeneities in the structure of the material when rolled below the transition temperature of the material.
  • the invention has for its object to provide a generic method with which a rolled product having a small cross-sectional area with a high surface quality and with a finer microstructure of the material that is homogeneously formed over the cross section can be produced in a simple manner with advantageous usage properties and good further processability.
  • the process according to the invention is characterized in that the pre-material or rolling stock is pre-deformed in a first step before it is warmed up to a temperature of improved deformability and then rolled, the material properties of which are changed. It has been shown that a reduction in the cross-sectional area of the rolling stock during a pre-deformation, preferably at substantially room temperature, and a consolidation and adjustment of an internal stress state in the material produce new dislocations in the crystal lattice, which cause dislocations to migrate and block and cause a lattice tension .
  • the heating of the rolling stock provided in the second step of the method according to the invention in the case of hardenable steels preferably to a temperature just below the transition temperature or the Ac 1 temperature, the lattice tension is stabilized and in the subsequent rolling deformation even at lower degrees of deformation a special grain refinement is achieved, which is intensified with the further rolling steps. If deep pre-deformation is carried out by rolling with a cross-sectional area reduction of at least 1.8%, the rolled product has a particularly homogeneous, finely structured structure of the material with advantageous usage properties.
  • the pre-deformation significantly improves the transition conditions for the electrical current in the contact area of a conductive heating device, so that no surface and structural defects result from arcing and / or local material overheating.
  • a cross-sectional area constancy of the rolling stock that can be achieved by the pre-deformation additionally results in an easier and more precise temperature control during the conductive heating.
  • the invention also relates to an arrangement for carrying out the method, which is explained in more detail with reference to the schematic drawing.
  • a raw material (7) in the descaled, pickled, ground or the like state of a provision device (1) e.g. removed from a drum (11) or (not shown) from a stack and fed to a pre-shaping device (2).
  • a shaping device can consist of two successive cold rolling stands (21, 22), in which the raw material cross section is reduced and a precise round or flat cross section is rolled.
  • a drawing device or the like can also be used for the pre-deformation, but the start of the method is made more difficult or more complex to carry out.
  • a heating device (3) After the rolled material emerges from the pre-forming device, it has essentially straightness, a smooth surface with a constant cross section or constant cross-sectional shape and a crystal lattice strain in the material.
  • a heating device (3) a circuit is closed by means of contact rollers (31, 32), an electrical current flow from a current source through the rolling stock and resistance heating is achieved.
  • a regulation of the energy supply and the like and / or a control of the method can be carried out with a temperature measuring device (30) which is connected downstream of the heating zone. Provision can also be made for a temperature compensation device (4) to be arranged in front of a deformation device (5).
  • the deformation device (5) preferably consists of at least two roll stands (51, 52) or a cassette rolling mill for a minimum deformation of 50% in total.
  • the finished product is stored by storage device (6), e.g. Drum (61), or stack container added.
  • storage device (6) e.g. Drum (61), or stack container added.
  • the preforming device (2) and the rolling device (5) and, if appropriate, the contact rollers of the heating device (3) are controlled in such a way that the exit speed of the rolling stock after the preforming, the passage speed through the heating device and the entry speed into the rolling device is essentially the same and tensile stresses prevail in the rolling stock lying between them.
  • a temperature-controlled overall control has proven to be advantageous for such a control.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Metal Rolling (AREA)
  • Heat Treatment Of Steel (AREA)

Abstract

The invention relates to a method and an arrangement for the rolling of wires and rods with a reduction in cross-section of at least 50%. According to the invention the cross-sectional area of the rolling stock is reduced and its properties modified in a first step involving a preliminary deformation, whereupon the rolling stock is heated and further deformed in a second step.

Description

Die Erfindung betrifft ein Verfahren und eine Anordnung zum Walzen von Draht- und Stabmaterial aus metallischen Werkstoffen, wobei dem Walzgut eine Verminderung der Querschnittsfläche von mindestens 50% erteilt wird.The invention relates to a method and an arrangement for rolling wire and rod material made of metallic materials, wherein the rolling stock is given a reduction in the cross-sectional area of at least 50%.

Für eine Herstellung von Draht- und Stabmaterial werden durchwegs Walz- oder Ziehverfahren angewendet, wobei Vormaterial mit großer Querschnittsfläche bzw. mit großem Durchmesser, insbesondere über 10 mm, durch Walzen bei hohen Temperaturen, vorzugsweise über 1000°C, und Vormaterial mit geringem Durchmesser, insbesondere unter 5 mm, durch Ziehen, zumeist in mehreren Schritten, bei Raumtemperatur, gegebenenfalls mit Weichglühbehandlungen zwischen den Ziehschritten, verformt wird.Rolling or drawing processes are used throughout for the production of wire and rod material, raw material with a large cross-sectional area or with a large diameter, in particular over 10 mm, by rolling at high temperatures, preferably over 1000 ° C., and raw material with a small diameter, in particular less than 5 mm, by drawing, usually in several steps, at room temperature, optionally with soft annealing treatments between the drawing steps.

Bei einem bekannten Verfahren der genannten Gattung ( CH-PS-654 496) wird Draht mit geringem Querschnitt hergestellt, indem ein kontinuierliches isothermes Walzen in einer mit beheizten Walzen ausgerüsteten Walzenstraße angewendet wird, wonach gegebenenfalls ein anschließendes Ziehen ohne Zwischenglühung erfolgt. Dabei wird die Vorwärm-und Walztemperatur hoch gewählt, um eine Materialverfestigung zu vermeiden bzw. Zwischenglühoperationen einzusparen. Nachteilig dabei sind eine Oxidation der Oberfläche, eine grobe Gefügestruktur sowie die Härtung von höher kohlenstoffhaltigen Legierungen bei rascher Abkühlung aus der Walzhitze.In a known method of the type mentioned (CH-PS-654 496), wire with a small cross-section is produced by using continuous isothermal rolling in a roll train equipped with heated rolls, followed by a subsequent drawing without intermediate annealing. The preheating and rolling temperature is chosen high in order to avoid material hardening or to save intermediate annealing operations. Disadvantages here are oxidation of the surface, a coarse microstructure and the hardening of higher carbon alloys with rapid cooling from the rolling heat.

Bei einem anderen Verfahren zum Warmwalzen von hochfestem Stahl (GB-PA 2 194 186) wird das Walzgut in mindestens zwei Schritten gewalzt, wobei der letzte Schritt mit einer Verformung von mindestens 50% mit mindestens zwei Walzschritten bei einer Temperatur, welche nahe, aber über der AR₃ Temperatur der Legierung liegt, durchgeführt wird. Nachteilig dabei sind eine Oxidation des Vormaterials bei der Erwärmung und ein erhöhter Walzenverschleiß sowie Gefügeinhomogenitäten über den Querschnitt des Werkstückes durch gegebenenfalls Bildung von Oberflächenmartensit bei Zwischenkühlungen.In another method for hot rolling high-strength steel (GB-PA 2 194 186), the rolling stock is rolled in at least two steps, the last step involving a deformation of at least 50% with at least two rolling steps at a temperature which is close to, but above the AR₃ temperature of the alloy, is carried out. Disadvantages here are oxidation of the primary material during heating and increased roller wear, as well as structural inhomogeneities over the cross section of the workpiece due to the formation of surface martensite during intermediate cooling.

Bei einem weiteren Walzverfahren zur Herstellung von Stahlband (DE-OS 2 725 155) wurde vorgeschlagen, einen Draht entkohlungsfrei in neutraler Atmosphäre auf eine höhere Temperatur als die AC₃ Temperatur der Legierung zu erhitzen und bei dieser Temperatur zu walzen, wonach das gewalzte Material abgekühlt und isotherm bis zur Erzielung einer bainitischen Struktur in einem Bereich oberhalb des Martensitpunktes gehalten wird. Nachteilig bei diesem für die Erzeugung von Verstärkungselementen in Fahrzeugluftreifen vorgesehenen Verfahren sind ein Vergütungsgefüge, welches im wesentlichen keine Weiterverarbeitung mittels thermischer Prozesse vorsieht, sowie die weitgehend durch den Umwandlungsvorgang nicht verringerte Austenitkorngröße.In a further rolling process for the production of steel strip (DE-OS 2 725 155) it has been proposed to heat a wire without decarburization in a neutral atmosphere to a temperature higher than the AC₃ temperature of the alloy and to roll at this temperature, after which the rolled material is cooled and isothermally until a bainitic structure is achieved in an area above the martensite point. Disadvantages of this method, which is provided for the production of reinforcing elements in pneumatic vehicle tires, are a tempering structure which essentially does not provide any further processing by means of thermal processes, and the austenite grain size which is largely not reduced by the conversion process.

Aus der FR-PS-2 579 116 ist zur kontinuierlichen Herstellung von metallischen Profilen ein Verfahren bekannt, bei welchem ein Draht-oder Stabmaterial der Bevorratungseinrichtung entnommen und in einer Rollenrichtmaschine gerade gerichtet wird, wonach das Walzgut zuerst konduktiv vorgewärmt und anschließend induktiv endgewärmt und mit mehreren Walzschritten verformt wird. Dieses Verfahren ist aufwendig, weil eine Oberflächenreinigung des Walzgutes, z.B. durch Bürsten, vor der Ronduktiverwärmung erforderlich sein kann. Weiters können dabei durch Unebenheiten der Oberfläche und daher punktförmiger Stromeinleitung in das Vormaterial in diesem Einbrennstellen oder Bereiche, die kurzfristig auf hohe Temperatur gebracht werden und somit aufhärten, gebildet werden. Mittels aufwendiger induktiver Endwärmung sollen bessere Aufheizbedingungen erreicht werden. Durch den Richtvorgang entstehen im Vormaterial stellenweise, insbesondere in der oberflächennahen Zone des Vormaterials, plastische Verformungen bzw. verfestigte Stellen, die bei einer Walzung unterhalb der Umwandlungstemperatur des Materials Inhomogenitäten im Gefüge des Werkstoffes bewirken können.From FR-PS-2 579 116 a method is known for the continuous production of metallic profiles, in which a wire or rod material is removed from the storage device and straightened in a roller straightening machine, after which the rolled material is first conductively preheated and then inductively final heated and with is deformed several rolling steps. This process is complex because surface cleaning of the rolling stock, for example by brushing, may be necessary before the conductive heating. Furthermore, unevenness in the surface and therefore punctiform introduction of current into the primary material in this stoving point or areas which are brought to high temperature for a short time and thus harden can be formed. Better heating conditions are to be achieved by means of complex inductive final heating. The straightening process creates in the primary material in places, especially in the near-surface zone of the primary material, plastic deformations or solidified points, which can cause inhomogeneities in the structure of the material when rolled below the transition temperature of the material.

Für ein Warmziehen von härtbaren Stählen wurde gemäß AT-PS 227 643 ein Verfahren vorgeschlagen, mit welchem das Ziehgut konduktiv bis zu einer Temperatur unter A₁ erwärmt wird. Dieses Verfahren ist weitgehend nur für oberflächenbehandeltes bzw. oberflächenbearbeitetes Vormaterial geeignet, wobei die Gefügestruktur vom Ziehvorgang und insbesondere vom Gefügezustand im Vormaterial abhängig ist.For a hot drawing of hardenable steels, a method was proposed according to AT-PS 227 643, with which the drawn material is heated up to a temperature below A 1. This method is largely only suitable for surface-treated or surface-processed raw material, the microstructure being dependent on the drawing process and in particular on the structural condition in the raw material.

Der Erfindung liegt die Aufgabe zugrunde, ein gattungsgemäßes Verfahren zu schaffen, mit welchem auf einfache Weise ein eine geringe Querschnittsfläche aufweisendes Walzprodukt mit hoher Oberflächengüte und mit über den Querschnitt homogen ausgebildeter feinerer Gefügestruktur des Werkstoffes mit vorteilhaften Gebrauchseigenschaften und guter Weiterverarbeitbarkeit hergestellt werden kann.The invention has for its object to provide a generic method with which a rolled product having a small cross-sectional area with a high surface quality and with a finer microstructure of the material that is homogeneously formed over the cross section can be produced in a simple manner with advantageous usage properties and good further processability.

Diese Aufgabe wird bei einem Verfahren der eingangs genannten Art durch die kennzeichnenden Merkmale des Anspruchs 1 gelöst. Vorteilhafte Ausgestaltungen und Weiterbildungen sind in den Ansprüchen 1- 8 gekennzeichnet.This object is achieved in a method of the type mentioned at the outset by the characterizing features of claim 1. Advantageous refinements and developments are characterized in claims 1-8.

Weiters ist es Aufgabe der Erfindung, eine Anordnung zum Walzen anzugeben, welche sich durch einen besonders einfachen Aufbau auszeichnet und eine Herstellung von Walzprodukten mit hoher Genauigkeit und besonderen Eigenschaften gewährleistet.Furthermore, it is an object of the invention to provide an arrangement for rolling, which is characterized by a particularly simple structure and ensures the production of rolled products with high accuracy and special properties.

Diese weitere Aufgabe wird bei einer gattungsgemäßen Anordnung durch die kennzeichnenden Merkmale des Anspruches 9 gelöst. Weitere bevorzugte Weiterbildungen der Erfindung ergeben sich aus den kennzeichnenden Merkmalen der Ansprüche 10 bis 15.This further object is achieved in a generic arrangement by the characterizing features of claim 9. Further preferred developments of the invention result from the characterizing features of claims 10 to 15.

Das erfindungsgemäße Verfahren zeichnet sich dadurch aus, daß vor dem Aufwärmen auf eine Temperatur verbesserter Verformbarkeit und einem anschließenden Walzen das Vormaterial bzw. Walzgut in einem ersten Schritt vorverformt wird, wobei dessen Werkstoffeigenschaften geändert werden. Es hat sich gezeigt, daß eine Verringerung der Querschnittsfläche des Walzgutes bei einer Vorverformung, vorzugsweise bei im wesentlichen Raumtemperatur, und eine Verfestigung und Einstellung eines inneren Spannungszustandes im Werkstoff, neue Versetzungen im Kristallgitter erzeugen, die Versetzungen zum Wandern bringen und blockieren und eine Gitterverspannung bewirken. Wie sich überraschenderweise weiter gezeigt hat, wird durch die im zweiten Schritt des erfindungsgemäßen Verfahrens vorgesehene Erwärmung des Walzgutes, bei härtbaren Stählen vorzugsweise auf eine Temperatur knapp unterhalb der Umwandlungstemperatur bzw. der Ac₁ Temperatur, die Gitterspannung labilisiert und bei der nachfolgenden Walzverformung schon bei geringeren Verformungsgraden eine besondere Kornfeinung erreicht, die mit den weiteren Walzschritten intensiviert wird. Wird eine tiefreichende Vorverformung durch Walzen mit einer Querschnittsflächenverminderung von mindestens 1,8% durchgeführt, so ergibt sich im Walzprodukt eine besonders homogene, fein ausgebildete Gefügestruktur des Werkstoffes mit vorteilhaften Gebrauchseigenschaften. Es hat sich auch gezeigt, daß durch die Vorverformung die Übergangsbedingungen für den elektrischen Strom im Kontaktbereich einer Konduktiverwärmungseinrichtung wesentlich verbessert werden, so daß daraus keinerlei Oberflächen-und Gefügefehler durch eine Lichtbogenbildung und/oder örtliche Materialüberhitzung entstehen. Eine durch die Vorverformung erreichbare Querschnittsflächenkonstanz des Walzgutes bewirkt zusätzlich eine leichtere und genauere Temperaturregelung bei der konduktiven Erwärmung. Bei einer Verwendung von gebeiztem oder entzundertem Vormaterial ist das erfindungsgemäße Verfahren besonders vorteilhaft anwendbar und es können damit Walzprodukte mit besonderer Innen- und Oberflächengüte hergestellt werden.The process according to the invention is characterized in that the pre-material or rolling stock is pre-deformed in a first step before it is warmed up to a temperature of improved deformability and then rolled, the material properties of which are changed. It has been shown that a reduction in the cross-sectional area of the rolling stock during a pre-deformation, preferably at substantially room temperature, and a consolidation and adjustment of an internal stress state in the material produce new dislocations in the crystal lattice, which cause dislocations to migrate and block and cause a lattice tension . As has surprisingly been shown further, by the heating of the rolling stock provided in the second step of the method according to the invention, in the case of hardenable steels preferably to a temperature just below the transition temperature or the Ac 1 temperature, the lattice tension is stabilized and in the subsequent rolling deformation even at lower degrees of deformation a special grain refinement is achieved, which is intensified with the further rolling steps. If deep pre-deformation is carried out by rolling with a cross-sectional area reduction of at least 1.8%, the rolled product has a particularly homogeneous, finely structured structure of the material with advantageous usage properties. It has also been shown that the pre-deformation significantly improves the transition conditions for the electrical current in the contact area of a conductive heating device, so that no surface and structural defects result from arcing and / or local material overheating. A cross-sectional area constancy of the rolling stock that can be achieved by the pre-deformation additionally results in an easier and more precise temperature control during the conductive heating. When using pickled or descaled primary material, the method according to the invention can be used particularly advantageously, and rolled products with a special inner and surface quality can be produced with it.

Die Erfindung betrifft auch eine Anordnung zur Durchführung des Verfahrens, welche anhand der schematischen Zeichnung näher erläutert wird.The invention also relates to an arrangement for carrying out the method, which is explained in more detail with reference to the schematic drawing.

Es zeigt Fig. 1 den prinzipiellen Aufbau der Anordnung.1 shows the basic structure of the arrangement.

Bei der in Fig. 1 dargestellten Anordnung wird ein Vormaterial (7) im entzunderten, gebeizten, geschliffenen od. dgl. Zustand einer Bereitstellungseinrichtung (1), z.B. einer Trommel (11) oder (nicht dargestellt) einem Stapel entnommen, und einer Vorverformungseinrichtung (2) zugeführt. Eine derartige Verformungseinrichtung kann aus zwei aufeinanderfolgenden Kaltwalzgerüsten (21,22) bestehen, in welchen der Vormaterialquerschnitt verringert und ein genauer Rund- oder Flachquerschnitt gewalzt wird.In the arrangement shown in Fig. 1, a raw material (7) in the descaled, pickled, ground or the like state of a provision device (1), e.g. removed from a drum (11) or (not shown) from a stack and fed to a pre-shaping device (2). Such a shaping device can consist of two successive cold rolling stands (21, 22), in which the raw material cross section is reduced and a precise round or flat cross section is rolled.

Zur Vorverformung kann auch eine Zieheinrichtung oder dgl. verwendet werden, wobei jedoch der Verfahrensbeginn erschwert bzw. aufwendiger durchführbar wird.A drawing device or the like can also be used for the pre-deformation, but the start of the method is made more difficult or more complex to carry out.

Nach dem Austritt des Walzmaterials aus der Vorverformungseinrichtung besitzt dieses im wesentlichen Geradheit, eine glatte Oberfläche mit konstantem Querschnitt bzw. gleichbleibender Querschnittsform und eine Kristallgitterverspannung im Werkstoff. In einer Erwärmungseinrichtung (3) wird mittels Kontaktrollen ( 31, 32) ein Stromkreis geschlossen, ein elektrischer Stromfluß von einer Stromquelle durch das Walzgut bewirkt und eine Widerstandserwärmung erzielt. Mit einer Temperaturmeßeinrichtung (30), welche der Erwärmungszone nachgeschaltet ist, kann eine Regelung der Energiezufuhr und dgl. und/oder eine Steuerung des Verfahrens vorgenommen werden. Es kann auch vorgesehen sein, eine Temperaturausgleichseinrichtung (4) einer Verformungseinrichtung (5) vorzuordnen. Die Verformungseinrichtung (5) besteht vorzugsweise aus mindestens zwei Walzgerüsten ( 51, 52) oder einem Kassettenwalzwerk für eine Mindestverformung von insgesamt 50 %.After the rolled material emerges from the pre-forming device, it has essentially straightness, a smooth surface with a constant cross section or constant cross-sectional shape and a crystal lattice strain in the material. In a heating device (3), a circuit is closed by means of contact rollers (31, 32), an electrical current flow from a current source through the rolling stock and resistance heating is achieved. A regulation of the energy supply and the like and / or a control of the method can be carried out with a temperature measuring device (30) which is connected downstream of the heating zone. Provision can also be made for a temperature compensation device (4) to be arranged in front of a deformation device (5). The deformation device (5) preferably consists of at least two roll stands (51, 52) or a cassette rolling mill for a minimum deformation of 50% in total.

Das Fertigprodukt wird von Lagerungseinrichtung (6), z.B. Trommel (61) , oder Stapelbehältnis aufgenommen. Besonders gute Ergebnisse werden mit einer erfindungsgemäßen Anordnung erzielt, wenn die Vorverformungseinrichtung (2) und die Walzeinrichtung (5) und gegebenenfalls die Kontaktrollen der Erwärmungseinrichtung (3) derart gesteuert werden, daß die Austrittsgeschwindigkeit des Walzgutes nach der Vorverformung, die Durchgangsgeschwindigkeit durch die Erwärmungseinrichtung und die Eintrittsgeschwindigkeit in die Walzeinrichtung im wesentlichen gleich groß sind und im dazwischen liegenden Walzgut Zugspannungen herrschen. Für eine derartige Steuerung hat sich eine temperaturgeführte Gesamtregelung als vorteilhaft erwiesen.The finished product is stored by storage device (6), e.g. Drum (61), or stack container added. Particularly good results are achieved with an arrangement according to the invention if the preforming device (2) and the rolling device (5) and, if appropriate, the contact rollers of the heating device (3) are controlled in such a way that the exit speed of the rolling stock after the preforming, the passage speed through the heating device and the entry speed into the rolling device is essentially the same and tensile stresses prevail in the rolling stock lying between them. A temperature-controlled overall control has proven to be advantageous for such a control.

Claims (15)

Verfahren zum Walzen von Draht- oder Stabmaterial aus metallischen Werkstoffen, wobei dem Walzgut eine Verminderung der Querschnittsfläche von mindestens 50% erteilt wird, dadurch gekennzeichnet, daß in einem ersten Schritt mit einer Vorverformung die Querschnittsfläche des Walzgutes verringert wird und dessen Werkstoffeigenschaften geändert werden, worauf in einem zweiten Schritt das Walzgut auf eine Temperatur verbesserter Verformbarkeit erwärmt und weiterverformt bzw. gewalzt wird.Method for rolling wire or rod material made of metallic materials, whereby the rolling stock is given a reduction in the cross-sectional area of at least 50%, characterized in that in a first step the cross-sectional area of the rolling stock is reduced and its material properties are changed with a preliminary deformation, whereupon in a second step, the rolling stock is heated to a temperature of improved deformability and further deformed or rolled. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß im ersten Schritt das Walzgut durch Kaltumformen, vorzugsweise bei einer im wesentlichen der Raumtemperatur entsprechenden Temperatur, vorverformt und verfestigt und ein innerer Spannungszustand im Werkstoff eingestellt wird, wobei eine Querschnittsflächenverminderung von mindestens 1,8 %, vorzugsweise von mindestens 4%, vorgenommen wird.A method according to claim 1, characterized in that in the first step the rolling stock is pre-deformed and solidified by cold forming, preferably at a temperature substantially corresponding to room temperature, and an internal stress state is set in the material, a cross-sectional area reduction of at least 1.8%, preferably of at least 4%. Verfahren nach Anspruch 1 und 2, dadurch gekennzeichnet, daß die im ersten Schritt vorgesehene Vorverformung und die Verfestigung und die Einstellung eines inneren Spannungszustandes im Werkstoff mittels Kaltwalzens, insbesondere mit zumindest zwei aufeinanderfolgenden Kalibrierungen, durchgeführt wird.Method according to Claims 1 and 2, characterized in that the pre-deformation provided in the first step and the consolidation and setting of an internal stress state in the material is carried out by means of cold rolling, in particular with at least two successive calibrations. Verfahren nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß das im ersten Schritt vorverformte und kaltverfestigte und mit einem inneren Spannungszustand im Werkstoff versehene Walzgut im zweiten Schritt mittels eines Schnellerwärmungsverfahrens , insbesondere konduktiv bzw. durch Leitung von elektrischem Strom, in einer vorzugsweise eine veränderbare Länge aufweisenden Erwärmungsstrecke auf eine Temperatur verbesserter Verformbarkeit erwärmt und mit mindestens zwei aufeinanderfolgenden Walzschritten in Walzrichtung weiterverformt wird.Method according to one of claims 1 to 3, characterized in that the rolled material preformed and cold-worked in the first step and provided with an internal stress state in the material in the second step by means of a rapid heating process, in particular conductively or by conduction of electric current, is heated in a heating section preferably having a variable length to a temperature of improved deformability and is further deformed in the rolling direction with at least two successive rolling steps. Verfahren nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß im zweiten Schritt das erwärmte Walzgut mit einer Querschnittsflächenverminderung von mindestens 10 %, vorzugsweise mindestens 20 %, je Walzschritt, insgesamt von mindestens 50 % , vorzugsweise von mindestens 70%, verformt wird.Method according to one of claims 1 to 4, characterized in that in the second step the heated rolling stock is deformed with a cross-sectional area reduction of at least 10%, preferably at least 20%, per rolling step, in total of at least 50%, preferably at least 70%. Verfahren nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß eine Gefügeumwandlung erfahrende metallische Werkstoffe, insbesondere härtbare Stähle und Legierungen, im zweiten Schritt mittels eines Schnellerwärmungsverfahrens auf eine Walztemperatur von höchstens der Ac₁ Temperatur bzw. der Umwandlungstemperatur in das Gamma- Gefüge erwärmt und mit mindestens zwei Walzschritten in Walzrichtung verformt werden, wobei gegebenenfalls durch Kühlung bzw. Verwendung von Kühlmittel eine Temperaturerhöhung im Walzgut bei der Weiterverformung verhindert wird.Method according to one of claims 1 to 5, characterized in that a structural transformation undergoing metallic materials, in particular hardenable steels and alloys, is heated in a second step by means of a rapid heating process to a rolling temperature of at most the Ac₁ temperature or the transition temperature into the gamma structure and are deformed in the rolling direction with at least two rolling steps, an increase in temperature in the rolling stock being prevented during further shaping, if appropriate by cooling or using coolant. Verfahren nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, daß nach dem ersten Schritt unmittelbar der zweite Schritt angeschlossen wird bzw. daß die Verfahrensschritte in einer Linie unmittelbar aufeinander folgend durchgeführt werden.Method according to one of claims 1 to 6, characterized in that, after the first step, the second step is connected immediately, or in that the method steps are carried out in a line immediately following one another. Verfahren nach einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, daß die Vorverformung im ersten Schritt und/oder die Weiterverformung im zweiten Schritt derart ausgeführt bzw. gesteuert werden( wird), daß dem zwischenliegenden Walzgut Zugspannungen, insbesondere konstante Zugspannungen, aufgebracht werden.Method according to one of claims 1 to 7, characterized in that the preliminary deformation in the first step and / or the further deformation in the second step are carried out or controlled in such a way that tensile stresses, in particular constant tensile stresses, are applied to the intermediate rolling stock. Anordnung zum Walzen von Draht- oder Stabmaterial aus metallischen Werkstoffen, wobei dem Walzgut eine Verminderung der Querschnittsfläche von mindestens 50 % erteilt wird, insbesondere zur Durchführung des Verfahrens nach einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, daß einer Erwärmungseinrichtung (3), insbesondere einer Schnellerwärmungseinrichtung, mit Energieeinbringung in das Walzgut durch direkten Stromdurchgang und einer Walzeinrichtung (5) eine Vorverformungseinrichtung (2) vorgeordnet ist.Arrangement for rolling wire or rod material from metallic materials, the rolling stock a reduction in Cross-sectional area of at least 50% is granted, in particular for carrying out the method according to one of claims 1 to 7, characterized in that a heating device (3), in particular a rapid heating device, with energy input into the rolling stock through direct current passage and a rolling device (5) Preforming device (2) is arranged upstream. Anordnung nach Anspruch 8, dadurch gekennzeichnet, daß die Vorverformungseinrichtung durch eine Kaltwalzeinrichtung, vorzugsweise eine mindestens zweistufige Kaltwalzeinrichtung, insbesondere mit mindestens zwei aufeinanderfolgenden Walzgerüsten (21,22) mit Flach- oder vorzugsweise Kaliberwalzen gebildet ist.Arrangement according to claim 8, characterized in that the pre-forming device is formed by a cold rolling device, preferably an at least two-stage cold rolling device, in particular with at least two successive roll stands (21, 22) with flat or preferably caliber rolls. Anordnung nach Anspruch 8 oder 9, dadurch gekennzeichnet,daß die Walzeinrichtung (5) für eine mindestens zweistufige Verformung, vorzugweise als mehrgerüstiges Walzwerk ( 51,52), insbesondere Kassettenwalzwerk, ausgebildet ist.Arrangement according to claim 8 or 9, characterized in that the rolling device (5) is designed for at least two-stage deformation, preferably as a multi-stand rolling mill (51, 52), in particular a cassette rolling mill. Anordnung nach einem der Ansprüche 9 bis 11, dadurch gekennzeichnet, daß die Vorverformungseinrichtung (2) und/oder die Walzeinrichtung (5) und gegebenenfalls die Erwärmungseinrichtung (3) einstellbare Antriebe aufweisen, welche vorzugsweise mit einer Steuerung verbunden und gemeinsam regelbar sind.Arrangement according to one of claims 9 to 11, characterized in that the pre-shaping device (2) and / or the rolling device (5) and optionally the heating device (3) have adjustable drives which are preferably connected to a control and can be regulated together. Anordnung nach einem der Ansprüche 9 bis 12, dadurch gekennzeichnet, daß der Erwärmungseinrichtung (3) zumindest eine Temperaturmeßeinrichtung (30) für das Walzgut nachgeschaltet ist, von der gegebenenfalls die Leistungszufuhr zur Erwärmungseinrichtung (3) und/oder der (die) Antrieb(e) gesteuert sind (ist).Arrangement according to one of claims 9 to 12, characterized in that the heating device (3) is followed by at least one temperature measuring device (30) for the rolling stock, from which, if necessary, the power supply to the heating device (3) and / or the drive (s) ) are controlled. Anordnung nach einem der Ansprüche 9 bis 13, dadurch gekennzeichnet, daß die Vorverformungseinrichtung (2) und die Erwärmungseinrichtung (3) und gegebenenfalls eine Temperaturausgleichszone (4) sowie die Walzeinrichtung (5) in Walzrichtung hintereinander angeordnet sind, wobei das Walzgut (7) im wesentlichen geradlinig durchleit- bzw. verarbeitbar ist.Arrangement according to one of claims 9 to 13, characterized in that the pre-shaping device (2) and the heating device (3) and optionally a temperature compensation zone (4) and the rolling device (5) in the rolling direction one behind the other are arranged, the rolling stock (7) being able to be passed through or processed essentially in a straight line. Verwendung einer Anordnung nach einem der Ansprüche 9 bis 14 zur Verformung von härtbaren Stählen, vorzugsweise Werkzeugstählen, insbesondere Schnellarbeitsstählen.Use of an arrangement according to one of claims 9 to 14 for deforming hardenable steels, preferably tool steels, in particular high-speed steels.
EP91890010A 1990-02-13 1991-01-24 Method and arrangement for rolling of rods and wires Expired - Lifetime EP0442864B1 (en)

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Application Number Priority Date Filing Date Title
AT319/90 1990-02-13
AT0031990A AT394670B (en) 1990-02-13 1990-02-13 METHOD AND ARRANGEMENT FOR ROLLING WIRE AND ROD MATERIAL

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EP0442864A1 true EP0442864A1 (en) 1991-08-21
EP0442864B1 EP0442864B1 (en) 1994-06-22

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JP (1) JPH04272135A (en)
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996030135A1 (en) * 1995-03-31 1996-10-03 Fintube Limited Partnership Process for making a strip from a hot rolled rod
US5638714A (en) * 1994-04-20 1997-06-17 Fintube Limited Partnership Process for making a strip from a rod
CN104889293A (en) * 2015-06-10 2015-09-09 天津市安博尔金属制品有限公司 Flat wire forming machine for cleaning ball

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AT256006B (en) * 1961-11-25 1967-08-10 Moossche Eisenwerke Ag Process for rolling out profiles by means of caliber rollers
DE2352880A1 (en) * 1973-04-09 1974-10-17 Schwermaschb Kom Ernst Thaelma PROCESS FOR ROLLING WIRE AND BAR IN DUO ROLLING STANDS
DE2455922A1 (en) * 1974-11-26 1976-06-10 Inst Metallofiziki Akademii Na Carbon steel wire and strip - alternately cold- and warm- worked to give high tensile strength and ductility
EP0098658A1 (en) * 1982-07-05 1984-01-18 Lamitref Aluminium Method for the production of metallic wire, wire obtained by this method and device for carrying out this method
CH669128A5 (en) * 1986-05-13 1989-02-28 Moos Stahl Ag High yield strength precision wire rod prodn. - by stretching and calibrating, useful for reinforcing rod mfr.
EP0314667A1 (en) * 1987-10-29 1989-05-03 BÖHLER Gesellschaft m.b.H. Process and apparatus for manufacturing thin wires, rods, pipes or sections made of steels or alloys with a low deformability, particularly of hardenable steels

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT256006B (en) * 1961-11-25 1967-08-10 Moossche Eisenwerke Ag Process for rolling out profiles by means of caliber rollers
DE2352880A1 (en) * 1973-04-09 1974-10-17 Schwermaschb Kom Ernst Thaelma PROCESS FOR ROLLING WIRE AND BAR IN DUO ROLLING STANDS
DE2455922A1 (en) * 1974-11-26 1976-06-10 Inst Metallofiziki Akademii Na Carbon steel wire and strip - alternately cold- and warm- worked to give high tensile strength and ductility
EP0098658A1 (en) * 1982-07-05 1984-01-18 Lamitref Aluminium Method for the production of metallic wire, wire obtained by this method and device for carrying out this method
CH669128A5 (en) * 1986-05-13 1989-02-28 Moos Stahl Ag High yield strength precision wire rod prodn. - by stretching and calibrating, useful for reinforcing rod mfr.
EP0314667A1 (en) * 1987-10-29 1989-05-03 BÖHLER Gesellschaft m.b.H. Process and apparatus for manufacturing thin wires, rods, pipes or sections made of steels or alloys with a low deformability, particularly of hardenable steels

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5638714A (en) * 1994-04-20 1997-06-17 Fintube Limited Partnership Process for making a strip from a rod
WO1996030135A1 (en) * 1995-03-31 1996-10-03 Fintube Limited Partnership Process for making a strip from a hot rolled rod
CN104889293A (en) * 2015-06-10 2015-09-09 天津市安博尔金属制品有限公司 Flat wire forming machine for cleaning ball

Also Published As

Publication number Publication date
DE59101963D1 (en) 1994-07-28
ATA31990A (en) 1991-11-15
AT394670B (en) 1992-05-25
EP0442864B1 (en) 1994-06-22
ATE107546T1 (en) 1994-07-15
JPH04272135A (en) 1992-09-28

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