FR2686149A3 - Longitudinal member for furnace for heating metallurgical products - Google Patents
Longitudinal member for furnace for heating metallurgical products Download PDFInfo
- Publication number
- FR2686149A3 FR2686149A3 FR9200218A FR9200218A FR2686149A3 FR 2686149 A3 FR2686149 A3 FR 2686149A3 FR 9200218 A FR9200218 A FR 9200218A FR 9200218 A FR9200218 A FR 9200218A FR 2686149 A3 FR2686149 A3 FR 2686149A3
- Authority
- FR
- France
- Prior art keywords
- heating resistors
- slabs
- electric heating
- metal tube
- furnace
- 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.)
- Granted
Links
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
- F27B9/30—Details, accessories, or equipment peculiar to furnaces of these types
- F27B9/36—Arrangements of heating devices
-
- 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
- F27B9/06—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity heated without contact between combustion gases and charge; electrically heated
- F27B9/062—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity heated without contact between combustion gases and charge; electrically heated electrically heated
- F27B9/063—Resistor heating, e.g. with resistors also emitting IR rays
-
- 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
- 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 tunnel furnace 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 tunnel furnace
- 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 tunnel furnace on rails, e.g. under the action of scrapers or pushers
- F27B9/222—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 on rails, e.g. under the action of scrapers or pushers the path comprising a section specially adapted for effecting equalisation of the temperature of the charge
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D3/00—Charging; Discharging; Manipulation of charge
- F27D3/02—Skids or tracks for heavy objects
- F27D3/022—Skids
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Heat Treatments In General, Especially Conveying And Cooling (AREA)
Abstract
Description
L'invention concerne un longeron de four de réchauffage de demi-produits métallurgiques tels que des brames d'acier. The invention relates to a longitudinal member of a reheating furnace for metallurgical semi-finished products such as steel slabs.
Dans le processus de fabrication de produits sidérurgiques on est amené à réchauffer à haute température les demi-produits. C'est ainsi que pour fabriquer des tôles à chaud ou des bobines on prend des demi-produits tels que des brames, on les chauffe à une température voisine de 1200"C et on les lamine par exemple sur un train à bandes. In the process of manufacturing steel products, the semi-finished products are heated to a high temperature. Thus, to manufacture hot sheets or coils, semi-finished products such as slabs are taken, they are heated to a temperature in the region of 1200 "C and they are rolled, for example, on a strip train.
Pour réchauffer les demi-produits, on les fait passer dans des fours de réchauffage continus. Ces fours sont constitués d'une enceinte munie de brûleurs, d'une évacuation de fumée, d'une porte d'entrée et d'une porte de sortie pour les demi-produits. A l'intérieur de l'en- ceinte des longerons s'étendent sur toute la longueur du four. Les brames reposent sur ces longerons et constituent un lit continu. Certains longerons sont animés d'un mouvement qui fait avancer pas à pas le lit de brames de telle sorte que chaque brame introduite à une extrémité du four, se déplace sur toute la longueur du four et ressort à l'autre extrémité. Les longerons peuvent être tous fixes. Dans ce cas, chaque brame nouvellement enfournée vient pousser le lit de brames qui glisse sur les longerons et la dernière brame est poussée hors du four du côté de la sortie. To reheat the semi-finished products, they are passed through continuous reheating ovens. These ovens consist of an enclosure fitted with burners, a smoke outlet, an entry door and an exit door for semi-finished products. Inside the enclosure of the longitudinal members extend over the entire length of the oven. The slabs rest on these beams and constitute a continuous bed. Some longitudinal members are animated with a movement which advances the slab bed step by step so that each slab introduced at one end of the furnace moves over the entire length of the furnace and exits at the other end. The beams can all be fixed. In this case, each newly baked slab pushes the slab bed which slides on the side members and the last slab is pushed out of the oven on the outlet side.
Lors de la traversée du four les brames sont chauffées sous l'effet du rayonnement thermique issu des brûleurs et des parois du four et par contact avec les fumées chaudes. When passing through the oven, the slabs are heated under the effect of thermal radiation from the burners and the walls of the oven and by contact with hot smoke.
Ce chauffage se fait par la surface des brames qui reçoit le rayonnement ou qui est exposée aux fumées. This heating is done by the surface of the slabs which receives the radiation or which is exposed to the fumes.
Les parties des brames qui reposent sur les longerons sont protégées du rayonnement. Il en résulte que ces parties sont moins chauffées que le reste des brames et constituent ce qu'on appelle des traces noires. The parts of the slabs which rest on the side members are protected from radiation. As a result, these parts are less heated than the rest of the slabs and constitute what are called black traces.
Les traces noires présentent un inconvénient au cours du laminage. En effet, le comportement du métal lors du laminage dépend de sa température et les hétérogénéités de température dans les brames conduisent à des hétérogénéités sur les produits laminés. The black traces have a drawback during rolling. Indeed, the behavior of the metal during rolling depends on its temperature and the temperature heterogeneities in the slabs lead to heterogeneities on the rolled products.
Le but de la présente invention est de diminuer l'intensité des traces noires dans les demi-produits sortant d'un four de réchauffage à longerons de façon à réduire les hétérogénéités dans les produits laminés. The object of the present invention is to reduce the intensity of the black traces in the semi-finished products leaving a reheating furnace with beams so as to reduce the heterogeneities in the rolled products.
A cet effet, l'invention a pour objet un longeron de four de réchauffage en continu de produits métallurgiques du type comprenant un tube métallique parcouru par une circulation d'eau et portant sur une arête supérieure une pluralité de supports de produits métallurgiques, et un habillage en matériau réfractaire qui peut être constitué de deux demi-coquilles enserrant le tube métallique et comportant également au moins deux résistances électriques chauffantes disposées à la surface de l'habillage de part et d'autre de l'arête supérieure et s'étendant sur une partie de la longueur du longeron. To this end, the subject of the invention is a longitudinal member of a furnace for continuously reheating metallurgical products of the type comprising a metal tube traversed by a circulation of water and carrying on a top edge a plurality of supports for metallurgical products, and a covering in refractory material which may consist of two half-shells enclosing the metal tube and also comprising at least two electric heating resistors arranged on the surface of the covering on either side of the upper edge and extending over part of the length of the spar.
La barre en matériau réfractaire peut comporter deux faces planes longitudinales situées de part et d'autre de l'arête supérieure, lesdites faces planes étant inclinées par rapport à l'horizontale d'un angle supérieur à 25". The bar of refractory material may comprise two longitudinal flat faces located on either side of the upper edge, said flat faces being inclined relative to the horizontal by an angle greater than 25 ".
Les résistances chauffantes peuvent être constituées par des bandes ondulées. The heating resistors can consist of corrugated strips.
L'invention va maintenant être décrite plus en détail en regard de la planche de dessins annexée sur laquelle
- la figure 1 est une vue schématique en coupe longitudinale d'un four de réchauffage continu à longerons. The invention will now be described in more detail with reference to the attached drawing plate on which
- Figure 1 is a schematic view in longitudinal section of a continuous reheating furnace with beams.
- la figure 2 est une vue en coupe transversale d'un longeron selon l'invention. - Figure 2 is a cross-sectional view of a beam according to the invention.
- la figure 3 est une vue longitudinale partielle d'un longeron selon l'invention. - Figure 3 is a partial longitudinal view of a beam according to the invention.
- la figure 4 est une vue de dessus d'un longeron selon l'invention. - Figure 4 is a top view of a beam according to the invention.
Le four repéré généralement par 1 à la figure 1 comporte une enceinte 2 parallélépipédique munie d'ouvertures 3 et 4 à ses extrémités. Ces ouvertures 3 et 4 peuvent être fermées par des portes 5 et 6. La voûte 7 est munie d'une pluralité de brûleurs 8. Les murs verticaux latéraux sont également munis d'une pluralité de brûleurs 9. A l'intérieur du four 1, des longerons 10 s'étendent longitudinalement sur toute la longueur du four. Ces longerons 10 reposent sur une pluralité de colonnes 11. The oven generally identified by 1 in FIG. 1 comprises a rectangular enclosure 2 provided with openings 3 and 4 at its ends. These openings 3 and 4 can be closed by doors 5 and 6. The roof 7 is provided with a plurality of burners 8. The lateral vertical walls are also provided with a plurality of burners 9. Inside the oven 1 , side members 10 extend longitudinally over the entire length of the oven. These beams 10 rest on a plurality of columns 11.
Sur les longerons 10 sont posées des brames 12 qui forment un lit quasiment continu.On the longitudinal members 10 are placed slabs 12 which form an almost continuous bed.
Certains longerons sont fixes. D'autres longerons sont mobiles et animés d'un mouvement cyclique qui permet de faire avancer le lit de brames. Some beams are fixed. Other beams are mobile and animated in a cyclic movement which makes it possible to advance the slab bed.
Les longerons mobiles sont soulevés ce qui soulève les brames puis déplacés vers l'avant, ce qui fait avancer les brames, puis redescendus ce qui permet de reposer les brames sur les longerons fixes dans une position avancée par rapport à la position antérieure, puis les longerons mobiles sont reculés pour être ramenés à leur position initiale. The movable beams are raised which raises the slabs and then moved forward, which advances the slabs, then lowered which allows the slabs to rest on the fixed beams in an advanced position relative to the previous position, then the mobile side members are moved back to be brought back to their initial position.
Ainsi, par ce mouvement, on fait avancer pas à pas le lit de brames. Une brame introduite par l'ouverture 3 traverse tout le four avant de ressortir par l'ouverture 4. Pendant cette traversée la brame est chauffée par le rayonnement issu des brûleurs 8 et 9, par le rayonnement issu des parois du four qui sont portées à haute température et par contact avec les fumées chaudes produites par les brûleurs. Thus, by this movement, the slab bed is advanced step by step. A slab introduced through the opening 3 passes through the entire oven before emerging through the opening 4. During this crossing the slab is heated by the radiation from the burners 8 and 9, by the radiation from the walls of the oven which are brought to high temperature and by contact with the hot fumes produced by the burners.
Le longeron objet de l'invention est constitué de deux demi-coquilles 13 et 14 réfractaires (figure 2) qui enserrent un tube métallique 15 parcouru par de l'eau 16 de refroidissement. Les demi-coquilles constituent un habillage du tube métallique. Une pluralité de plots métalliques 17 sont soudés sur le tube métallique et dépassent de l'habillage sur l'arête supérieure 22 du longeron. Les brames reposent sur ces plots métalliques. The spar object of the invention consists of two refractory half-shells 13 and 14 (Figure 2) which enclose a metal tube 15 through which the cooling water 16. The half-shells constitute a covering for the metal tube. A plurality of metal studs 17 are welded to the metal tube and protrude from the covering on the upper edge 22 of the spar. The slabs rest on these metal studs.
Des inserts réfractaires 50 peuvent être interposés entre les plots métalliques 17.Refractory inserts 50 can be interposed between the metal studs 17.
Chaque demi-coquille 13 ou 14 comporte à sa partie externe, une face plane 18, 18' inclinée par rapport à l'horizontale d'un angle compris entre 30O et 45 , et une surface cylindrique 19, 19'. Each half-shell 13 or 14 has at its external part, a flat face 18, 18 'inclined with respect to the horizontal by an angle between 30O and 45, and a cylindrical surface 19, 19'.
Sur les faces planes sont posées des résistances électriques chauffantes 20, 20' maintenues par des plots 21, 21' suivant une disposition sinusoïdale. La partie inférieure des ondulations des résistances électriques déborde de la face plane correspondante 18 ou 18'. On the flat faces are placed electric heating resistors 20, 20 'held by studs 21, 21' in a sinusoidal arrangement. The lower part of the corrugations of the electrical resistances projects beyond the corresponding flat face 18 or 18 ′.
Ces résistances sont des rubans ou des bandes ondulés longitudinalement comme celà est représenté à la figure 3. Ces résistances 20, 20' sont reliées à un dispositif d'alimentation électrique et de régulation non représenté. These resistors are ribbons or bands corrugated longitudinally as shown in FIG. 3. These resistors 20, 20 'are connected to a power supply and regulation device, not shown.
Les faces planes 18 et 18' ont pour fonction de supporter les résistances lorsqu'elles sont à haute température de façon à ce qu'elles ne fluent pas. The flat faces 18 and 18 ′ have the function of supporting the resistors when they are at high temperature so that they do not flow.
Les faces planes 18 et 18' sont inclinées par rapport à l'horizontale pour éviter que la calamine qui tombe des brames vienne s'accumuler sur les résistances électriques chauffantes et forme un écran thermique. La calamine tombant sur les faces planes est évacuée par les espaces libres à la partie inférieure des ondulations des résistances qui ne repose pas sur les faces planes. The flat faces 18 and 18 ′ are inclined relative to the horizontal to prevent the scale which falls from the slabs from accumulating on the electric heating resistors and forming a thermal screen. The scale falling on the flat faces is evacuated by the free spaces at the bottom of the corrugations of the resistors which do not rest on the flat faces.
Les résistances électriques chauffantes ne s'étendent pas nécessairement sur toute la longueur des longerons, mais s' étendent au moins sur la partie située du côté de l'ouverture de sortie 4. The electric heating resistors do not necessarily extend over the entire length of the longitudinal members, but extend at least over the part situated on the side of the outlet opening 4.
En effet, on divise en général un four en plusieurs zones. En partant de l'entrée 3 et en allant vers la sortie 4 on a successivement - une zone de préchauffage, - une ou plusieurs zones de chauffage dans la ou lesquelles les brames sont portées progressivement à haute température, - une zone d'égalisation dans laquelle on homogénéise la température à l'intérieur des brames. In fact, an oven is generally divided into several zones. Starting from inlet 3 and going towards outlet 4, there is successively - a preheating zone, - one or more heating zones in which the slabs are gradually brought to high temperature, - an equalization zone in which homogenizes the temperature inside the slabs.
On a constaté que pour effacer les traces noires, la présence de résistances chauffantes était efficace surtout dans la zone d'égalisation. Aussi, les résistances chauffantes s'étendent préférentiellement sur la partie des longerons qui correspond à la zone d'égalisation. It was found that to erase the black traces, the presence of heating resistors was effective especially in the equalization zone. Also, the heating resistors preferably extend over the part of the longitudinal members which corresponds to the equalization zone.
Lorsque les brames arrivent dans la zone d 'éga- lisation, les traces noires qui se situent au droit des longerons viennent en regard des résistances électriques chauffantes. When the slabs arrive in the equalization zone, the black traces which are located to the right of the side members come opposite the electric heating resistors.
Les résistances électriques chauffantes, alimentées en courant électrique sont portées à haute température. The electric heating resistors, supplied with electric current are brought to high temperature.
Le rayonnement des résistances chauffantes est reçu par la partie des brames correspondant aux traces noires. Cet apport calorifique supplémentaire réchauffe le métal au droit des traces noires, ce qui tend à les faire disparaître ou au moins à les atténuer. The radiation from the heating resistors is received by the part of the slabs corresponding to the black traces. This additional calorific contribution heats the metal to the right of the black marks, which tends to make them disappear or at least to attenuate them.
On remarquera que le longeron peut comporter des glissières continues plutôt que des plots. It will be noted that the spar may include continuous slides rather than studs.
Claims (5)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR9200218A FR2686149B3 (en) | 1992-01-10 | 1992-01-10 | OVEN RUNNER FOR HEATING METALLURGICAL PRODUCTS. |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR9200218A FR2686149B3 (en) | 1992-01-10 | 1992-01-10 | OVEN RUNNER FOR HEATING METALLURGICAL PRODUCTS. |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| FR2686149A3 true FR2686149A3 (en) | 1993-07-16 |
| FR2686149B3 FR2686149B3 (en) | 1993-12-31 |
Family
ID=9425530
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| FR9200218A Expired - Lifetime FR2686149B3 (en) | 1992-01-10 | 1992-01-10 | OVEN RUNNER FOR HEATING METALLURGICAL PRODUCTS. |
Country Status (1)
| Country | Link |
|---|---|
| FR (1) | FR2686149B3 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1997031233A1 (en) * | 1996-02-22 | 1997-08-28 | Consultant Gas Engineers Limited | Tunnel kiln |
| GB2326463A (en) * | 1996-02-22 | 1998-12-23 | Consultant Gas Eng Ltd | Tunnel klin |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE560197A (en) * | ||||
| DE638993C (en) * | 1934-01-16 | 1936-11-26 | Bbc Brown Boveri & Cie | Electrically heated tunnel oven |
| FR2458775A1 (en) * | 1979-06-09 | 1981-01-02 | Karrena Gmbh | Industrial kiln pipe cladding - is secured by radial holders with ends extending in axial direction |
| JPS60200908A (en) * | 1984-03-22 | 1985-10-11 | Sumitomo Metal Ind Ltd | Heating furnace for steel material |
| EP0424818A1 (en) * | 1989-10-24 | 1991-05-02 | General Signal Corporation | Furnace and heating unit therefor |
-
1992
- 1992-01-10 FR FR9200218A patent/FR2686149B3/en not_active Expired - Lifetime
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE560197A (en) * | ||||
| DE638993C (en) * | 1934-01-16 | 1936-11-26 | Bbc Brown Boveri & Cie | Electrically heated tunnel oven |
| FR2458775A1 (en) * | 1979-06-09 | 1981-01-02 | Karrena Gmbh | Industrial kiln pipe cladding - is secured by radial holders with ends extending in axial direction |
| JPS60200908A (en) * | 1984-03-22 | 1985-10-11 | Sumitomo Metal Ind Ltd | Heating furnace for steel material |
| EP0424818A1 (en) * | 1989-10-24 | 1991-05-02 | General Signal Corporation | Furnace and heating unit therefor |
Non-Patent Citations (1)
| Title |
|---|
| PATENT ABSTRACTS OF JAPAN vol. 10, no. 63 (C-332)(2120) 13 Mars 1986 & JP-A-60 200 908 ( SUMITOMO KINZOKU KOGYO K K ) 11 Octobre 1985 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1997031233A1 (en) * | 1996-02-22 | 1997-08-28 | Consultant Gas Engineers Limited | Tunnel kiln |
| GB2326463A (en) * | 1996-02-22 | 1998-12-23 | Consultant Gas Eng Ltd | Tunnel klin |
Also Published As
| Publication number | Publication date |
|---|---|
| FR2686149B3 (en) | 1993-12-31 |
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