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EP0170585B1 - Dispositif pour l'homogénéisation en température de produits métalliques en défilement - Google Patents

Dispositif pour l'homogénéisation en température de produits métalliques en défilement Download PDF

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Publication number
EP0170585B1
EP0170585B1 EP85401464A EP85401464A EP0170585B1 EP 0170585 B1 EP0170585 B1 EP 0170585B1 EP 85401464 A EP85401464 A EP 85401464A EP 85401464 A EP85401464 A EP 85401464A EP 0170585 B1 EP0170585 B1 EP 0170585B1
Authority
EP
European Patent Office
Prior art keywords
inductors
products
width
support members
active surfaces
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
Application number
EP85401464A
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German (de)
English (en)
French (fr)
Other versions
EP0170585A1 (fr
Inventor
Jean-Luc Roth
Hervé Sierpinski
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.)
Institut de Recherches de la Siderurgie Francaise IRSID
Original Assignee
Institut de Recherches de la Siderurgie Francaise IRSID
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 Institut de Recherches de la Siderurgie Francaise IRSID filed Critical Institut de Recherches de la Siderurgie Francaise IRSID
Priority to AT85401464T priority Critical patent/ATE34832T1/de
Publication of EP0170585A1 publication Critical patent/EP0170585A1/fr
Application granted granted Critical
Publication of EP0170585B1 publication Critical patent/EP0170585B1/fr
Expired legal-status Critical Current

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Classifications

    • 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/30—Details, accessories or equipment specially adapted for furnaces of these types
    • 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
    • C21D9/0081—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for slabs; for billets
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/14—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment
    • F27B9/20—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path
    • F27B9/201—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path walking beam furnace
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/14—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment
    • F27B9/20—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path
    • F27B9/22—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path on rails, e.g. under the action of scrapers or pushers

Definitions

  • the present invention relates to the homogenization in temperature of metal products, in particular steel slabs, intended for rolling and having previously been subjected to this effect to a not perfectly homogeneous heating.
  • thermal equalization zone Another solution consists in placing the heated products in the teminal part of the unheated oven (so-called thermal equalization zone) so as to allow a better distribution of the temperatures throughout the mass of the products.
  • thermal equalization zone This process is quite slow and homogenization is only acquired at the expense of productivity or the size of the installation and at the cost of significant additional energy expenditure.
  • the object of the present invention is to provide a solution which ensures at all points of the reheated product, a uniform temperature which is sufficient for the rolling operation, while avoiding the drawbacks of the previously mentioned known solutions.
  • the subject of the invention is a device for the temperature homogenization of moving metal products, in particular steel slabs, intended for rolling and previously raised in temperature in the heating zone of a reheating furnace having , following this heating zone provided with product support members, a thermal equalization zone comprising a hearth, device comprising a plurality of polyphase static inductors with sliding magnetic field, of elongated shape, characterized in that said inductors are placed in the thermal equalization zone of the reheating furnace, parallel to themselves at the rate of one inductor per support member and in the extension of the support members of the products in movement from the heating zone, and the active face of the inductors, facing the products, has a width at least equal to the width of said support members, preferably between 1 and 4 times this width and preferably still equal to approximately 3 times this width.
  • the conductors with which the inductors are fitted are oriented perpendicular to the direction of travel of the products.
  • the present invention recommends selective inductive heating, located in the temperature equalization zone of the reheating oven, and located under the predetermined parts of the metal product which constitute the black traces.
  • the location of the inductors in the extension of the metal product support rails guarantees their permanent arrangement with regard to the black traces which it is desired to eliminate.
  • polyphase static inductors with a sliding field of elongated shape is particularly suitable because they make it possible to locally generate large induced currents, and therefore, a concentrated calorific contribution and localized at the places of the product that one wants to heat.
  • thermal map of a "black trace” is generally in the form of a family of relatively deep sinusoidal isotherms in the section of the metal.
  • the spatial distribution of the power induced in the product by a sliding field inductor tends precisely to follow such a thermal profile.
  • the width of the active face of the inductors is preferably in a ratio of 3 to 1 (or approaching) with the width of the support members. Beyond a ratio of 4 to 1, a non-negligible part of the induced power is unnecessarily injected at the periphery of the black trace, while below a ratio of 1 to 2, the inductor becomes undersized for the purpose of erasing the black traces.
  • the invention presents a decisive economic interest.
  • demand is now shifting towards metallic products having particular mechanical characteristics, in particular of resilience and weldability, which require a very precise control of the grain size in the metal.
  • One of the means of obtaining such a characteristic consists in carrying out a so-called “low temperature” reheating, that is to say in baking the metal products at around 950 ° C. (instead of 1100-1200 ° C. as is usually does).
  • this process while being energetically economical, requires precise control of the heating of the product.
  • the device according to the invention which guarantees homogeneous heating within the metal, makes it possible to envisage the feasibility of so-called “low temperature” heating.
  • the slabs 3 are joined by their small lateral face so as to form a continuous sheet which moves from right to left in the direction indicated by the arrow F, using a pusher symbolized in 1 at the entrance 2 of the oven.
  • the slabs thus travel slowly in a straight line through the oven from inlet 2 to outlet 4 where they are unloaded one by one on an inclined plane 5 which deposits them on a path with transport rollers 6 for their routing to the rolling plant (not shown).
  • the oven comprises two thermal zones: a first zone 7 called “heating” with a length of about 18 m, in the upstream part of the oven and a second zone 8, called “equalization” with a length of 12 m approximately, in the downstream part of the oven.
  • the heating zone 7 is conventionally composed of a first enclosure 7 ′, called the preheating of cold products, followed by a second enclosure 7 ′′ ensuring the heating of the preheated products to their nominal temperature.
  • the slabs 3 are placed on the wear strip of metal slides 9 internally cooled by circulation of water. These slides 9, 20 cm wide, spaced from each other by a distance of the order of 1.5 m, form a parallel network oriented in the direction of movement of the slabs 3.
  • the heating zone also includes front burners 10 and 11 respectively arranged in the upper and lower parts of the oven.
  • the equalization zone 8 can also be equipped with front burners 10 ′, but for the sole purpose of compensating for the heat losses which occur through the walls of the furnace.
  • the fumes produced in the oven circulate against the slabs 3 up to the vicinity of the oven door where they are evacuated by a chimney 12.
  • the slab-slide contact slows down the rapid rise in temperature of the slab 3 at this point and leads to the formation of cold marks or "black marks".
  • the slabs 3 are placed on a solid hearth 13 made of refractory material.
  • This in accordance with the invention, is fitted with inductors with a sliding magnetic field 14 of elongated shape.
  • These inductors 14 are placed in the extension of the slides 9 at the rate of one inductor per slide, and extend, in the example under consideration, over the entire length of the equalization zone 8.
  • the active face 15 of the inductors placed opposite the hearth 13 has a length of 6m and a width of approximately 50 cm.
  • the inductor 14 is of planar structure and comprises a laminated magnetic yoke 16 having on the active face 15 regularly spaced parallel notches 17 serving as housing for conductors 18, formed of rectangular hollow copper bars to allow an internal circulation of a cooling fluid.
  • the heads of the coils protruding laterally from the magnetic yoke are shown diagrammatically in 19 and 19 ′ and folded down to reduce their size under the floor 13.
  • the conductors are adequately connected to a three-phase industrial frequency power supply (not shown) to produce a mobile magnetic field sliding along the longitudinal axis of the inductor.
  • these inductors 14 are placed under the floor 13 in the extension of the slides 9. In this way, the black traces 20 generated locally in the slabs 3 in contact with these slides, naturally come to pass above inductors during the progression of the slabs in the zone 8 of thermal equalization.
  • an insert 21 made of a refractory material with high thermal insulating properties (for example of fibrous refractory based on alumina) was housed in a recess 22 made for this purpose on the underside of the sole. 13 above the inductor 14.
  • the role of this insert is to reinforce the thermal protection of the inductor 14 with respect to the heat given off by the slab 3.
  • FIG. 3 shows that this result can be easily obtained using an insert 21 with a concave base, serving as an imprint on the inductor 14.
  • the action of the inductors 14 can be regulated in the usual way, for example by acting on the intensity of the excitation current, or on its frequency.
  • An advantageous variant consists in providing an active curved face of the inductor.
  • This arrangement can have an advantage insofar as the spatial distribution of the heating power induced in the slab 3 thus tends to approach even more the sinusoidal thermal profile of the "black trace" 20.
  • the structure of the inductor can be envisaged to provide a curved active face, by giving, for example, a semi-cylinder structure, or in the form of a circular sector to the inductor. .
  • the sliding direction of the magnetic field can be modified according to the orientation of the busbars.
  • a transverse arrangement of the conductive bars 18 that is to say perpendicular to the direction of travel of the slabs 3) was used.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Heat Treatments In General, Especially Conveying And Cooling (AREA)
  • General Induction Heating (AREA)
  • Metal Rolling (AREA)
  • Devices That Are Associated With Refrigeration Equipment (AREA)
  • Soil Working Implements (AREA)
  • Tunnel Furnaces (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Control And Other Processes For Unpacking Of Materials (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Control Of Heat Treatment Processes (AREA)
  • Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Disintegrating Or Milling (AREA)
  • Resistance Heating (AREA)
EP85401464A 1984-07-27 1985-07-17 Dispositif pour l'homogénéisation en température de produits métalliques en défilement Expired EP0170585B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT85401464T ATE34832T1 (de) 1984-07-27 1985-07-17 Vorrichtung zur homogenisierung der temperatur von metallischen werkstuecken in kontinuierlicher bewegung.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8412228A FR2568359B1 (fr) 1984-07-27 1984-07-27 Dispositif pour l'homogeneisation en temperature par voie inductive de produits metalliques en defilement
FR8412228 1984-07-27

Publications (2)

Publication Number Publication Date
EP0170585A1 EP0170585A1 (fr) 1986-02-05
EP0170585B1 true EP0170585B1 (fr) 1988-06-01

Family

ID=9306724

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85401464A Expired EP0170585B1 (fr) 1984-07-27 1985-07-17 Dispositif pour l'homogénéisation en température de produits métalliques en défilement

Country Status (12)

Country Link
US (1) US4745252A (xx)
EP (1) EP0170585B1 (xx)
JP (1) JPS6144127A (xx)
KR (1) KR920001610B1 (xx)
AT (1) ATE34832T1 (xx)
AU (1) AU574208B2 (xx)
BR (1) BR8503562A (xx)
CA (1) CA1251640A (xx)
DE (1) DE3563115D1 (xx)
ES (1) ES8608665A1 (xx)
FR (1) FR2568359B1 (xx)
ZA (1) ZA855378B (xx)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1994008190A1 (en) * 1992-10-05 1994-04-14 Acon Finland Oy Ltd Method and apparatus for improving the performance of a heating furnace for metal slabs
JP2633792B2 (ja) * 1993-03-31 1997-07-23 本田技研工業株式会社 高周波加熱方法および装置
US6110805A (en) * 1997-12-19 2000-08-29 Micron Technology, Inc. Method and apparatus for attaching a workpiece to a workpiece support
NL1010415C2 (nl) * 1998-10-28 2000-05-01 Acon Europ Limited Inrichting voor het verhitten van een staalplaat voordat deze wordt uitgewalst.
FR2829232B1 (fr) * 2001-09-06 2004-08-20 Air Liquide Procede pour ameliorer le profil de temperature d'un four
US6841763B1 (en) * 2003-08-27 2005-01-11 Ksp Technologies Corp. Heat induction workstation
US8025711B2 (en) 2007-12-19 2011-09-27 Nu-Iron Technology, Llc System and method for producing metallic iron
ITUB20169915A1 (it) * 2016-01-12 2017-07-12 Siti B & T Group Spa Forno per ceramiche ad efficienza migliorata
CN112050644B (zh) * 2020-09-18 2024-12-06 五冶集团上海有限公司 带式烧结机风箱纵横梁的安装方法

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3342468A (en) * 1964-06-30 1967-09-19 United States Steel Corp Apparatus for removing cold skid marks from objects
FR1408638A (fr) * 1964-09-23 1965-08-13 Ofenbau Union Gmbh Foyer à sole pleine pour des fours industriels servant au traitement thermique de produits métallurgiques
DE1236545B (de) * 1965-12-09 1967-03-16 Bbc Brown Boveri & Cie Verfahren und Vorrichtung zur Beseitigung von Kuehlschatten an in einem Waermofen erwaermten Waermgut
DE1268644B (de) * 1965-12-17 1968-05-22 Didier Werke Ag Heizbalken fuer den Ausgleichsherd eines Stossofens
US3469052A (en) * 1967-09-01 1969-09-23 Westinghouse Electric Corp Heating apparatus for metal workpieces
US3471673A (en) * 1968-02-19 1969-10-07 United States Steel Corp Apparatus for inductively heating a traveling metal slab
US3715556A (en) * 1970-10-05 1973-02-06 Park Ohio Industries Inc Slab heating method and apparatus
US4087238A (en) * 1976-09-13 1978-05-02 United States Steel Corporation Method for enhancing the heating efficiency of continuous slab reheating furnaces
FR2372402A1 (fr) * 1976-11-25 1978-06-23 Siderurgie Fse Inst Rech Procede et dispositif pour l'homogeneisation en temperature de produits metalliques
US4289944A (en) * 1977-12-19 1981-09-15 Reese Thurston F Apparatus for reheating, storing and conveying cast bars
FR2417737A1 (fr) * 1978-02-16 1979-09-14 Stein Surface Dispositif pour supprimer ou reduire les traces noires sur les produits sortant d'un four
FR2445085A1 (fr) * 1978-12-22 1980-07-18 Courdille Rene Installation de chauffage par induction de produits metallurgiques plats
JPS57168489A (en) * 1981-04-07 1982-10-16 Mitsubishi Electric Corp Stationary induction heater

Also Published As

Publication number Publication date
CA1251640A (fr) 1989-03-28
ES8608665A1 (es) 1986-06-16
JPS6144127A (ja) 1986-03-03
BR8503562A (pt) 1986-04-22
US4745252A (en) 1988-05-17
KR860000902A (ko) 1986-02-20
FR2568359B1 (fr) 1987-01-09
ZA855378B (en) 1986-05-28
DE3563115D1 (en) 1988-07-07
EP0170585A1 (fr) 1986-02-05
ES545584A0 (es) 1986-06-16
ATE34832T1 (de) 1988-06-15
AU574208B2 (en) 1988-06-30
FR2568359A1 (fr) 1986-01-31
AU4525085A (en) 1986-01-30
KR920001610B1 (ko) 1992-02-20

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