EP0442864B1 - Méthode et arrangement pour le laminage de barres et fils - Google Patents

Méthode et arrangement pour le laminage de barres et fils Download PDF

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Publication number
EP0442864B1
EP0442864B1 EP91890010A EP91890010A EP0442864B1 EP 0442864 B1 EP0442864 B1 EP 0442864B1 EP 91890010 A EP91890010 A EP 91890010A EP 91890010 A EP91890010 A EP 91890010A EP 0442864 B1 EP0442864 B1 EP 0442864B1
Authority
EP
European Patent Office
Prior art keywords
rolling
temperature
moulding
accordance
rolled stock
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.)
Expired - Lifetime
Application number
EP91890010A
Other languages
German (de)
English (en)
Other versions
EP0442864A1 (fr
Inventor
Hans Dipl.-Ing. Lösch
Franz Rischka
Johann Eilmer
Karl Strahlhofer
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.)
Voestalpine Boehler Edelstahl GmbH
Original Assignee
Boehler Edelstahl GmbH
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 Boehler Edelstahl GmbH filed Critical Boehler Edelstahl GmbH
Publication of EP0442864A1 publication Critical patent/EP0442864A1/fr
Application granted granted Critical
Publication of EP0442864B1 publication Critical patent/EP0442864B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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, the rolling stock being 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, whereby starting material with a large cross-sectional area or with a large diameter, in particular over 10 ⁇ mm, by rolling at high temperatures, preferably over 10 ⁇ 0 ⁇ 0 ⁇ ° C, and starting 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 roller train equipped with heated rollers, after which a subsequent drawing is carried out without intermediate annealing.
  • the preheating and rolling temperature is chosen to be 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 alloys with a higher carbon content with rapid cooling from the rolling heat.
  • the rolling stock is rolled in at least two steps, the last step with 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 if necessary 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 rolling stock is first conductively preheated and then inductively final heated and with is deformed in several rolling steps.
  • This method 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 can result in burn-in points or areas which are brought to high temperature for a short time and thus harden. 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 which 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, before it is warmed up to a temperature of improved deformability and then rolled, the primary material or rolling stock is pre-deformed and solidified in a first step, the material properties of which are changed and an internal stress state is set in the material. It has been shown that a reduction in the cross-sectional area of the rolling stock with a pre-deformation of at least 1.8%, preferably at essentially room temperature, causes a hardening and setting of an internal stress state in the material, in which new dislocations caused dislocations to migrate in the crystal lattice and are mutually blocked and thereby create a grid tension.
  • the heating of the rolling stock provided for 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 Ac1 temperature, the lattice tension is stabilized and in the subsequent roll deformation even at low levels
  • a degree of deformation of at least 10% per pass achieves a special grain refinement that is intensified with the further rolling steps to a total of at least 50%.
  • deep pre-deformation is carried out by cold 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.
  • 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 easier and more precise temperature control during the conductive heating.
  • the method according to the invention can be used particularly advantageously, and rolled products with a special internal and surface quality can thus be produced.
  • the invention also relates to an arrangement for carrying out the method.
  • a rolling device for forming steels, metals and alloys with low deformability at room temperature which essentially consists of a heating device by means of direct current passage through the rolling stock for setting the temperature, a temperature compensation device and a deformation device for at least one there is two-stage deformation of the rolling stock.
  • a raw material (7) in descaled, pickled, ground or the like State of a provisioning 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 is effected 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 pre-shaping device (2) and the rolling device (5) and optionally the contact rollers of the heating device (3) are controlled in such a way that the exit speed of the rolling stock after the pre-shaping, 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 in between.
  • a temperature-controlled overall control has proven to be advantageous for such a control.

Landscapes

  • 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)

Claims (8)

  1. Méthode pour le laminage de fils et de barres en matériaux métalliques, dans laquelle le produit à laminer subit une réduction de surface de section d'au moins 50 %, caractérisée en ce que, dans une première étape, le produit à laminer est prédéformé par déformation à froid à une température qui correspond essentiellement à la température ambiante, avec une réduction de surface de section d'au moins 1,8 % du produit à laminer, ce qui le consolide et crée un état de tension dans le matériau, puis, dans une seconde étape, le produit à laminer est réchauffé à une température de meilleure déformabilité et sa déformation est poursuivie en au moins deux étapes successives de laminage avec une réduction de surface de section d'au moins 10 % par étape, et au moins 50 % au total.
  2. Méthode selon la revendication 1, caractérisée en ce que la prédéformation prévue à la première étape est réalisée au moyen d'un laminoir à froid, et en ce que le produit à laminer avec un état de tension dans le matériau est, dans la seconde étape, réchauffé à une température de meilleure déformabilité par conduction dans une boucle de réchauffage selon un procédé de réchauffage rapide connu en soi, puis sa déformation est poursuivie.
  3. Méthode selon l'une des revendications 1 ou 2, caractérisée en ce qu'un matériau métallique subissant une modification de structure est, dans la seconde étape, réchauffé à une température de laminage atteignant au maximum la température Acl ou bien la température de transformation dans la structure gamma, sa déformation se poursuivant à cette température, une élévation de température dans le produit à laminer lors de cette déformation complémentaire étant empêchée par refroidissement.
  4. Méthode selon l'une des revendications 1 à 3, caractérisée en ce que la seconde étape suit immédiatement la première étape, et en ce que la prédéformation de la première étape et/ou la déformation complémentaire de la seconde étape sont effectuées de telle sorte que des contraintes de tension sont apportées au produit à laminer entre les deux étapes.
  5. Arrangement pour le laminage de fils et de barres en matériaux métalliques, pour mettre en oeuvre la méthode selon l'une ou l'autre des revendications 1 à 4, comportant un dispositif de réchauffage (3) connu en soi, avec apport d'énergie dans le produit à laminer par passage direct de courant, et un dispositif de laminage (5) placé à la suite pour effectuer une déformation en au moins deux étapes, caractérisé en ce qu'un dispositif de prédéformation (2) constitué par un laminoir à froid est prévu en amont.
  6. Arrangement selon la revendication 5, caractérisé en ce que le dispositif de prédéformation (2) et/ou le dispositif de laminage (5) ainsi que le dispositif de réchauffage (3) disposent d'entraînements à vitesse variable reliés à une commande et susceptibles d'être réglés ensemble.
  7. Arrangement selon l'une des revendications 5 ou 6, caractérisé en ce que le dispositif de prédéformation (2) et le dispositif de réchauffage (3) et une zone d'équilibrage de température (4) ainsi que le dispositif de laminage (5) sont disposés à la suite les uns des autres dans le sens du laminage, le produit à laminer (7) étant passé et travaillé de façon linéaire.
  8. Utilisation d'un arrangement selon l'une des revendications 5 à 7 pour la déformation d'aciers durcissables.
EP91890010A 1990-02-13 1991-01-24 Méthode et arrangement pour le laminage de barres et fils Expired - Lifetime EP0442864B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AT0031990A AT394670B (de) 1990-02-13 1990-02-13 Verfahren und anordnung zum walzen von drahtund stabmaterial
AT319/90 1990-02-13

Publications (2)

Publication Number Publication Date
EP0442864A1 EP0442864A1 (fr) 1991-08-21
EP0442864B1 true EP0442864B1 (fr) 1994-06-22

Family

ID=3487419

Family Applications (1)

Application Number Title Priority Date Filing Date
EP91890010A Expired - Lifetime EP0442864B1 (fr) 1990-02-13 1991-01-24 Méthode et arrangement pour le laminage de barres et fils

Country Status (4)

Country Link
EP (1) EP0442864B1 (fr)
JP (1) JPH04272135A (fr)
AT (2) AT394670B (fr)
DE (1) DE59101963D1 (fr)

Families Citing this family (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 (fr) * 1995-03-31 1996-10-03 Fintube Limited Partnership Procede de production d'une bande de metal a partir d'une barre laminee a chaud
CN104889293B (zh) * 2015-06-10 2017-10-27 天津市安博尔金属制品有限公司 一种清洁球用扁丝成型机

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT256006B (de) * 1961-11-25 1967-08-10 Moossche Eisenwerke Ag Verfahren zum Auswalzen von Profilen mittels Kaliberwalzen
DD103569A1 (de) * 1973-04-09 1974-02-05 Flemming Folker Verfahren zum walzen von draht und stabstahl in duo-walzgeruesten
DE2455922C3 (de) * 1974-11-26 1980-11-27 Institut Metallofiziki Akademii Nauk Ukrainskoj Ssr, Kiew Verfahren zum Herstellen von langgestreckten Werkstücken wie Drähten, Bändern oder Profilen aus warmgewalzten Kohlenstoffstahl
LU84257A1 (fr) * 1982-07-05 1984-03-22 Lamitref Aluminium Procede de fabrication de fil metallique,fil metallique ainsi obtenu et unite de production utilisee pour appliquer ce procede
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.
AT393361B (de) * 1987-10-29 1991-10-10 Boehler Gmbh Verfahren und Vorrichtung zur Erzeugung dünner Drähte, Stäbe, Rohre und Profile aus Stählen und Legierungen mit geringem Formänderungsverm¦gen, insbes. aus härtbaren Stählen.

Also Published As

Publication number Publication date
DE59101963D1 (de) 1994-07-28
ATA31990A (de) 1991-11-15
ATE107546T1 (de) 1994-07-15
AT394670B (de) 1992-05-25
EP0442864A1 (fr) 1991-08-21
JPH04272135A (ja) 1992-09-28

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