EP0099383B1 - Four de prechauffage de materiaux allonges - Google Patents

Four de prechauffage de materiaux allonges Download PDF

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Publication number
EP0099383B1
EP0099383B1 EP83900423A EP83900423A EP0099383B1 EP 0099383 B1 EP0099383 B1 EP 0099383B1 EP 83900423 A EP83900423 A EP 83900423A EP 83900423 A EP83900423 A EP 83900423A EP 0099383 B1 EP0099383 B1 EP 0099383B1
Authority
EP
European Patent Office
Prior art keywords
hearth
tunnel
furnace
preheating furnace
shells
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
EP83900423A
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German (de)
English (en)
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EP0099383A1 (fr
Inventor
Friedrich Wilhelm Elhaus
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Individual
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Individual
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Publication date
Application filed by Individual filed Critical Individual
Priority to AT83900423T priority Critical patent/ATE20280T1/de
Publication of EP0099383A1 publication Critical patent/EP0099383A1/fr
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Publication of EP0099383B1 publication Critical patent/EP0099383B1/fr
Expired legal-status Critical Current

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Classifications

    • 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 tunnel furnace
    • 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
    • C21D9/0075—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for rods of limited length

Definitions

  • the invention relates to a heating furnace for elongated goods, such as rods, blocks, bars or the like, made of metal, in particular aluminum or aluminum alloys, with a hearth tunnel formed from continuous or segment-wise refractory, thin-walled hearth shells, the heating elements penetrating through the shell walls, such as burners , Hot gas nozzles or the like, can be heated, which are directed towards the goods which can be transported longitudinally into the hearth tunnel for direct loading thereof, and with an exhaust gas duct arranged in the upper furnace area and running parallel to the hearth tunnel.
  • a heating furnace for elongated goods such as rods, blocks, bars or the like, made of metal, in particular aluminum or aluminum alloys
  • a hearth tunnel formed from continuous or segment-wise refractory, thin-walled hearth shells, the heating elements penetrating through the shell walls, such as burners , Hot gas nozzles or the like, can be heated, which are directed towards the goods which can be transported longitudinally into the hearth tunnel
  • the invention has for its object to provide a heating furnace of the type mentioned in such a way that the energy supplied for heating is used more effectively with a simple, compact construction.
  • the hearth tunnel protrudes “integrated” into the exhaust gas duct which has thermal insulation.
  • the heat insulation of the exhaust gas duct covers the hearth shells of the hearth tunnel from the outside at least in their central area, so that the lower areas of the hearth shells remain free for assembly and maintenance purposes.
  • the invention achieves considerably improved energy utilization can be attributed to the fact that the exhaust gas is transferred from the hearth tunnel to the exhaust gas duct without any heat loss, for example via the upper gap between the vertically standing cooker shell halves. Due to the construction according to the invention, the middle and upper area of the hearth tunnel is through the exhaust duct itself, i. H. sufficient thermal insulation without any additional measures. Thermal insulation of the lower area of the hearth tunnel has been deliberately avoided in favor of better accessibility for assembly and maintenance purposes. According to the inventor's knowledge, the losses of radiant heat in the lower areas of the cooker shells are relatively small. The omission of thermal insulation in these lower areas is very advantageous because there remains space for the accommodation and accessibility of units such as burners, support frames for the cooker trays and the conveying device for the material to be heated.
  • the insulating parts can protrude vertically from the support parts or nestle against the upper areas of the hob shells.
  • thermo insulation is supported by support parts fixedly attached to a support frame of the oven and has removable insulating parts arranged above it, of which the lower support and insulate the hearth shells laterally.
  • the burners of the upper rows of burners penetrate removable insulating parts, while the burners of the lower rows of burners in the lower, non-heat-insulated area of the hearth shells are provided, and that each insulating part penetrated by burners has the same length as corresponding segments of the hearth shells.
  • the hot exhaust gas is passed from the exhaust duct into a preheating zone of the preheating furnace or another furnace for preheating the material (DE-OS 2637646), which ensures particularly economical fuel utilization.
  • a furnace group is advantageous in which the preheating furnace, with its exhaust gases, heats an upstream preheating furnace, which guides the exhaust gas via at least one fan to at least one row of slot nozzles arranged along the material and directs it to the material.
  • the construction according to the invention is particularly advantageous if the furnace space of the heating furnace is divided into several heating and control zones which are connected via the common flue gas duct. If individual zones are switched off when the target temperature is reached, they are not affected by the remaining zones despite the connection via the exhaust gas duct; the flue gases only flow longitudinally in the upper area in the common flue gas duct, advantageously in a preheating zone or for preheating the material in an upstream preheating furnace, in this way in a furnace group comprising the preheating furnace and the preheating furnace connected in series make optimal use of the heat content of the fuel.
  • the heating furnaces shown have a support frame 10 made of a steel structure.
  • the hearth shells 14 are pivotally mounted on support rails 16 in their lower region and are held in position by spacers 17.
  • only one burner row with premix burners 18 arranged in longitudinal rows perpendicular to the plane of the drawing are provided per hearth bowl row 14.
  • the burners 18 have burner nozzles 20 which protrude through openings 21 of the hearth shells into the cylindrical hearth tunnel 15 and act directly on the material.
  • the burners 18 are arranged in such a way that when the material 1 of different diameters is warmed up, good utilization of the surface for heat transfer and a rotationally symmetrical temperature distribution over the cross section of the material is achieved.
  • the burner nozzles 20 are adjusted in their output so that the desired temperature distribution is generated.
  • hot gas nozzles can also be provided for heating, which, for example, act on the material 1 with hot air, which can be heated electrically in a known manner.
  • the exhaust gases leave the hearth space 15 upwards through a longitudinal gap 30 formed by the hearth shell halves 14 at the spacers 17, from which they pass directly into an exhaust gas duct 32. From this, the exhaust gas is conveyed into a preheating zone, not shown, for the material 1 upstream of the preheating furnace, for. B. sucked by means of fans, not shown.
  • the exhaust gas duct has thermal insulation, the lower insulating parts 54 of which extend over the entire length of the furnace, leave a gap for the hearth tunnel 15 and lie against the middle regions of the hearth shells 14 from the outside.
  • the lower insulating parts 54 are supported by supports 52, which are fixedly attached to the support frame 10.
  • the main or upper section of the exhaust duct 32 is formed by two vertical insulating parts 56 and an upper insulating part 58 integral therewith.
  • the insulating parts 56, 58 of the upper part also extend over the entire length of the furnace.
  • the main section 56, 58 can thus be removed as a whole.
  • the hearth shells 14 are then held laterally by the lower insulating parts 54, but after removal of the spacers 17, they can be removed individually by gently pivoting inward about the respective pivot point on the mounting rails 16 for replacement.
  • the heat insulation has e.g. B. two layers, of which the inner consists of heat insulating, but poorly storing ceramic fibers, while the outer layer, which is in the range of lower temperatures, consists of mineral fibers.
  • FIG. 2 differs from that according to FIG. 1 only in that in addition to the lower burner row 18, an upper burner row 19 is provided for each range of stoves.
  • An adjustable throttle valve 24 is arranged in the fuel feed line 23 in order to adjust the upper burners relative to the lower burners.
  • the additional upper burner rows require the interposition of vertical insulating parts 59, which are segmented into segments according to the stoves 14, between the lower insulating parts 54, which extend over the entire length of the furnace, and the main or upper part of the exhaust gas duct 32, the insulating parts 60, 62, 64 of which in turn form a coherent part , consistently form a removable piece.
  • the piece 60, 62, 64 must be lifted off to replace the cooker bowls.
  • the corresponding insulating parts 59 must be removed so that the associated hearth shells 14 can be replaced after removing the spacers 17 as in the embodiment according to FIG. 1.
  • the somewhat more complicated structure in comparison with FIG. 1 is the price for the higher uniformity of the heating of the material achieved.
  • Fig. 3 shows in the right half a side view of a preheating furnace designated here at 90 according to Fig. 1 or Fig. 2 and in the left half a pre-preheating furnace which is heated by the exhaust gases of the heating furnace.
  • the exhaust duct 32 opens out via an opening 33 in the right end wall 34 in FIG.
  • the furnace chamber which is connected to the exhaust duct 32 via the opening 33 and is protected by thermal insulation 42 similar to that of the heating furnace 90, several circulation zones, e.g. B. two circulation zones 47, 48 each with a fan 43 which suck the exhaust gas in the direction of arrows F in Fig.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Thermal Sciences (AREA)
  • Physics & Mathematics (AREA)
  • General Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Tunnel Furnaces (AREA)
  • Furnace Details (AREA)
  • Heat Treatments In General, Especially Conveying And Cooling (AREA)

Claims (8)

1. Four de réchauffage pour produits allongés, tels que barres, lingots, billettes ou autres, en métal, notamment en aluminium ou en alliage d'aluminium, avec un tunnel de chauffage composé de chemises réfractaires à parois minces, assemblées de façon continue ou par segments, qui peut être chauffé au moyen d'éléments chauffants traversant les parois des chemises, qui sont dirigés vers les produits pouvant être transportés en long dans le tunnel de chauffage de façon à ce que ces derniers soient soumis directement à l'action de ces éléments chauffants, et avec un conduit de fumées disposé dans la partie supérieure du four et s'étendant parallèlement au tunnel de chauffage, caractérisé par le fait que le tunnel de chauffage (15) pénètre dans le conduit de fumées (32) présentant une isolation thermique (40; 50).
2. Four de réchauffage selon la revendication 1, caractérisé par le fait que l'isolation thermique du conduit de fumées (32) recouvre de l'extérieur les chemises (14) du tunnel de chauffage (15), au moins dans leur partie centrale.
3. Four de réchauffage selon la revendication 1 ou 2, caractérisé par le fait que l'isolation thermique est étayée par des éléments d'appui (52) fixés sur un châssis-support (10) du four, et présente des éléments isolants amovibles (54, 56, 58; 59, 60, 62, 64) placés dessus, dont les éléments inférieurs (54) isolent et étayent latéralement les chemises de foyer (14).
4. Four de réchauffage selon la revendication 3, caractérisé par le fait que les éléments isolants inférieurs (54) reposant sur les éléments d'appui (52) sont réalisés et peuvent être montés séparément des autres éléments isolants (56, 58; 59, 60, 62, 64) formant le conduit de fumées.
5. Four de réchauffage selon la revendication 3 ou 4, dans lequel des séries inférieures et supérieures de brûleurs sont réparties sur la circonférence du tunnel de chauffage, caractérisé par le fait que les brûleurs (19) des séries supérieures de brûleurs traversent des éléments isolants amovibles (59), tandis que les brûleurs (18) des séries inférieures de brûleurs sont placés dans la partie inférieure, non isolée thermiquement, des chemises de foyer, et que chaque élément isolant (59) traversé par des brûleurs (19) est de la même longueur que les segments correspondants (14) des chemises de foyer.
6. Four de réchauffage selon l'une quelconque des revendications 1 à 4, caractérisé par le fait que toutes les séries de brûleurs débouchent dans le tunnel de chauffage (15), en dessous de l'isolation thermique, et que le conduit de fumées (32) se présente sous la forme d'une unité de montage amovible.
7. Four de réchauffage selon l'une quelconque des revendications 1 à 5, caractérisé par le fait que l'isolation thermique comporte à l'intérieur au moins une couche de fibres céramiques, et à l'extérieur au moins une couche de fibres minérales.
8. Ensemble de fours, comportant un four de réchauffage qui chauffe par ses fumées un four de préchauffage placé en amont, lequel conduit les fumées au moyen d'au moins un ventilateur vers au moins une série d'injecteurs à fentes disposés le long des produits, et les dirige sur les produits au moyen de ces injecteurs, caractérisé par le fait que le conduit de fumées (32) d'un four de réchauffage selon l'une quelconque des revendications 1 à 7, est en grande partie aligné par rapport à un compartiment du four de préchauffage (40) contenant le ventilateur (43) et également protégé par une isolation thermique (42), et débouche à l'avant (en 33) dans ce compartiment (41).
EP83900423A 1982-02-02 1983-02-01 Four de prechauffage de materiaux allonges Expired EP0099383B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83900423T ATE20280T1 (de) 1982-02-02 1983-02-01 Anwaermofen fuer langgestrecktes gut.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3203433 1982-02-02
DE3203433A DE3203433C2 (de) 1982-02-02 1982-02-02 Anwärmofen für langgestrecktes Gut

Publications (2)

Publication Number Publication Date
EP0099383A1 EP0099383A1 (fr) 1984-02-01
EP0099383B1 true EP0099383B1 (fr) 1986-06-04

Family

ID=6154561

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83900423A Expired EP0099383B1 (fr) 1982-02-02 1983-02-01 Four de prechauffage de materiaux allonges

Country Status (6)

Country Link
US (1) US4541799A (fr)
EP (1) EP0099383B1 (fr)
AU (1) AU556135B2 (fr)
CA (1) CA1202174A (fr)
DE (2) DE3203433C2 (fr)
WO (1) WO1983002661A1 (fr)

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3418603C1 (de) * 1984-05-18 1985-03-21 Schweizerische Aluminium Ag, Chippis Anwaermofen fuer zylindrische Gueter
DE3434906C2 (de) * 1984-09-22 1993-03-04 Otto Junker Gmbh, 5107 Simmerath Vorrichtung zum Vorwärmen von metallischem Gut
DE19538364C5 (de) * 1995-10-14 2007-05-24 Carl Prof. Dr.-Ing. Kramer Vorrichtung zur Schnellerwärmung von Metall-Preßbolzen
IT1281108B1 (it) * 1995-12-27 1998-02-11 Siem Sas Di Barbero & C Forno a gas per il riscaldo in continuo di barre metalliche
DE19943354C1 (de) * 1999-09-10 2001-05-23 Carl Kramer Vorrichtung zur gleichmäßigen Schnellerwärmung von Pressbolzen oder Stangen, insbesondere aus Leichtmetalllegierungen
ES2213042T3 (es) * 1999-09-10 2004-08-16 Kramer, Carl, Prof.Dr.-Ing. Procedimiento de tratamiento termico de lingotes metalicos.
GB0127420D0 (en) * 2001-11-15 2002-01-09 Furnace Construction Co Ltd Incineration apparatus
DE102004020206A1 (de) * 2004-04-22 2005-11-10 Expert Engineering Gmbh Verfahren zum Behandeln von Stranggussstangen oder Stranggussbolzen
DE102006028712B4 (de) * 2006-06-20 2012-02-02 Otto Junker Gmbh Bolzenerwärmungsofen und Verfahren zur Bolzenerwärmung
DE102007062551B4 (de) * 2007-12-20 2012-02-23 Otto Junker Gmbh Vorrichtung und Verfahren zur Erwärmung von Metallbolzen
EP2398603A1 (fr) * 2009-02-23 2011-12-28 Extrutec GmbH Dispositif de préchauffage d'objets, en particulier de tubes, de barres ou de goujons en aluminium, ainsi qu'installation dotée d'un tel dispositif de préchauffage
DE202011101167U1 (de) * 2011-04-06 2011-07-06 Otto Junker GmbH, 52152 Vorrichtung zum Erwärmen von Metallbolzen
ITMI20110848A1 (it) * 2011-05-13 2012-11-14 Danieli Off Mecc Apparato per il trattamento termico in linea di semilavorati metallurgici
FR3018344B1 (fr) * 2014-03-04 2016-04-29 Cockerill Maintenance & Ingenierie Sa Four industriel pour chauffer des produits tels des produits siderurgiques
EP3177746A1 (fr) * 2014-08-08 2017-06-14 I.C.M.I. S.r.l. Four de rechauffage pour barres metalliques
CN105318715B (zh) * 2015-10-30 2017-12-19 重庆丰银包装材料有限公司 积木式连续式加热炉

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1378710A (en) * 1914-06-16 1921-05-17 Dynamidon G M B H Lining for kilns
GB191517574A (en) * 1915-12-16 1916-07-13 Colin Frederick Price Improvements in Furnaces for Heating Billets for Tool Forgings and the like.
GB647053A (en) * 1946-10-08 1950-12-06 Bernard Joseph Moore Improvements in gas- or oil-fired tunnel kilns
US2603470A (en) * 1949-04-26 1952-07-15 Selas Corp Of America Method and apparatus for heating
US2948237A (en) * 1958-02-17 1960-08-09 Florian C Toepel Revolving hearth for a combustion chamber
DE1189438B (de) * 1959-09-28 1965-03-18 Keramische Ind Bedarfs Kom Ges Tunnelofen mit Muffelkanaelen
US3273218A (en) * 1965-05-04 1966-09-20 Armrock Products Inc Kiln for rapid firing single layers of ceramic articles
DE1807504B2 (de) * 1968-11-07 1974-01-31 Friedrich Wilhelm Dipl.Ing. 5600 Wuppertal Elhaus Durchlauferwärmungsofen für Metallblöcke, -stangen od.dgl
US3837794A (en) * 1973-07-16 1974-09-24 Granco Equipment Billet heating
DE2357920A1 (de) * 1973-11-20 1975-05-22 I Khim Fiz Akademii Nauk Ssr Ofen zum oxydfreien waermen von zu verguetendem werkstoff
FR2354524A1 (fr) * 1976-06-08 1978-01-06 Porcher Ets Perfectionnements apportes aux fours a ceramique
DE2637646B2 (de) * 1976-08-20 1978-08-10 Friedrich Wilhelm Dipl.- Ing. 5600 Wuppertal Elhaus Anwärmofen

Also Published As

Publication number Publication date
AU1696083A (en) 1985-01-24
EP0099383A1 (fr) 1984-02-01
CA1202174A (fr) 1986-03-25
DE3203433C2 (de) 1984-08-09
WO1983002661A1 (fr) 1983-08-04
AU556135B2 (en) 1986-10-23
US4541799A (en) 1985-09-17
DE3363853D1 (en) 1986-07-10
DE3203433A1 (de) 1983-08-25

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