EP0311506B1 - Crucible for an induction furnace - Google Patents

Crucible for an induction furnace Download PDF

Info

Publication number
EP0311506B1
EP0311506B1 EP88402505A EP88402505A EP0311506B1 EP 0311506 B1 EP0311506 B1 EP 0311506B1 EP 88402505 A EP88402505 A EP 88402505A EP 88402505 A EP88402505 A EP 88402505A EP 0311506 B1 EP0311506 B1 EP 0311506B1
Authority
EP
European Patent Office
Prior art keywords
crucible
elements
conductive material
ducts
electrically conductive
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
EP88402505A
Other languages
German (de)
French (fr)
Other versions
EP0311506A1 (en
Inventor
Roger Boen
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.)
Commissariat a lEnergie Atomique et aux Energies Alternatives CEA
Original Assignee
Commissariat a lEnergie Atomique CEA
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 Commissariat a lEnergie Atomique CEA filed Critical Commissariat a lEnergie Atomique CEA
Publication of EP0311506A1 publication Critical patent/EP0311506A1/en
Application granted granted Critical
Publication of EP0311506B1 publication Critical patent/EP0311506B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00—Heating by electric, magnetic or electromagnetic fields
    • H05B6/02—Induction heating
    • H05B6/22—Furnaces without an endless core
    • H05B6/24—Crucible furnaces
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00—Heating by electric, magnetic or electromagnetic fields
    • H05B6/02—Induction heating
    • H05B6/22—Furnaces without an endless core

Definitions

  • the present invention relates to a particular construction of an induction furnace crucible of the type made of an electrically conductive material, such as copper, surrounded externally by an induction coil.
  • the cylindrical wall of such crucibles is subjected to significant overheating both because of the molten charge which it surrounds and as clearances by Joule effect due to the induced currents of which it is the seat. It is therefore important to limit these overheating by inserting cooling circuits inside the wall.
  • the obligation to limit the currents induced in this same wall which, in addition to the thermal losses which they produce, also create an electromagnetic decoupling between the turn and the load, means that the wall consists of the assembly of longitudinal elements by their transverse faces, like a barrel stave, with an electrical insulating joint between two adjacent elements.
  • Figure 1 shows in perspective and partial section one of these crucibles already known.
  • the inductor 1 is a turn wound around longitudinal elements 2 which have a section in the form of a crown sector which embraces an angle C '. They are assembled by their transverse faces 3 to form the cylindrical wall of a crucible, which further comprises a bottom which does not appear in the figure. Seals 4 of electrical insulating material are interposed between the adjacent elements 2 and are pressed between the transverse faces 3.
  • the elements 2 each contain a hydraulic cooling circuit which is here a U-shaped duct 5 which extends over all their length.
  • One of its branches 6 communicates with a water supply pipe 8, the other branch 7 with a water discharge pipe 9.
  • the cooling water therefore travels successively through the two branches 6 and 7 of the conduit in U 5.
  • the two branches 6 and 7 are located on the same circumference, halfway between the external and internal surfaces of the cylindrical wall of the crucible.
  • the angle C 'of the elements 2 must therefore be sufficient to embrace the two branches; here it is 24 °, when we would like it to be as small as possible.
  • the invention overcomes these drawbacks by overcoming the prejudice that the elements 2 must each be cooled by an independent circuit. It shows that it is perfectly possible to have circumferential cooling circuits which pass in turn through several elements 2. The seals 4 can indeed perfectly seal.
  • the invention therefore relates to a crucible made of an electrically conductive material of an induction furnace consisting of longitudinal elements assembled together according to their transverse faces by means of electrical insulating joints, characterized in that the elements are pierced with conduits leading to their transverse faces and leading to similar conduits of the elements to which they are assembled, and in that the joints are impervious to coolants passing through the conduits.
  • the inductor 1 of FIGS. 2A and 2B is the same as in the previous figure, and there are longitudinal elements 12 in the form of crown sectors which embrace an angle C much less than the angle C 'in FIG. 1: approximately one or two degrees. It can be seen that the elements 12 then have a greater thickness than their width between their transverse faces 13, which means that the currents induced by the inductor 1 cannot develop there and that the electromagnetic losses, as well as the heating which they produce by Joule effect, are very reduced. Indeed, electrical insulating joints 14 are interposed as before between adjacent longitudinal elements 12.
  • the seals 14 must be drilled in front of the conduits 15, and at the same time prevent leaks between the cooling network and the outside, that is to say seal.
  • FIG 3 shows a possible embodiment of the invention.
  • the wall of the crucible is cut diametrically.
  • the elements 12 have a lower heel 16 which is in the form of a projection 17 of their external surface and of a reentrant 18 of their internal surface.
  • the cooling network made up of the channels 15 here forms two nested propellers 15 ′ and 15 ", each of which opens at its lower end into a cylindrical supply water box 19 on which the reentrants 18 fit together, and at its upper end in a cylindrical drainage water box 20 which fits around the upper edge 21 of the elements 12.
  • the drainage water box 20 is supported on the upper edge 22 of a coating ring 23 disposed around the elements 12 and which is itself supported on the projections 17. It is electrically insulating such that the fiberglass.
  • conduits 15 can form any number of helices, which is only limited by reasons of ease of construction.
  • FIG. 4 represents another possible embodiment of the invention, which differs from the previous one in that the hydraulic circuit is formed this time of several horizontal channels 30 which each extend over a circumference of the cylindrical wall.
  • a longitudinal element 32 of particular shape is then provided, possibly of greater angular extension than the others, the section of which is in the shape of an H and which thus comprises an internal wall 33, an external wall 34 and a median cross-member 35 connecting the two walls 33 and 34.
  • the cross-piece separates two vertical channels 36 and 37; one of them 36, on the right in the drawing, is traversed by the cooling water arriving from a supply pipe 38 and distributes this water in the horizontal channels 30; the other, 37, on the left in the drawing, collects and collects the water which has passed through the horizontal channels 30 before drain it through a drain hose 39.
  • FIG. 5 A particular advantage of the invention appears in Figure 5.
  • longitudinal elements 42 having a cylindrical upper part 43 connecting to a lower part 44 widening downwards from the inside can perfectly be envisaged: the volume occupied by the molten charge is then cylindro-conical with the point of the cone at the bottom and it leads to a drain neck 45 of small diameter delimited by the lower parts 44.
  • These longitudinal elements 12 have a much narrower width near the drain neck 45. It is however possible to cool them at this location by gradually increasing the width (radial dimension) of the section of the cooling conduits 15 for those located downwards.
  • the arrangement of the conduits 15 in through channels therefore presents a double advantage: it is possible either to reduce the losses in the crucible by constructing it with thinner and numerous elements, or to ensure the cooling of narrowed zones.

Description

La présente invention se rapporte à une construction particulière de creuset de four à induction du type en matériau conducteur électrique, tel que du cuivre, entouré extérieurement par une spire d'induction.The present invention relates to a particular construction of an induction furnace crucible of the type made of an electrically conductive material, such as copper, surrounded externally by an induction coil.

La paroi cylindrique de tels creusets est soumise à des échauffements importants tant à cause de la charge fondue qu'elle entoure que des dégagements par effet Joule dus aux courants induits dont elle est le siège. Il importe donc de limiter ces échauffements en insérant des circuits de refroidissement à l'intérieur de la paroi. Toutefois, l'obligation de limiter les courants induits dans cette même paroi qui, outre les pertes thermiques qu'ils produisent, créent en outre un découplage électromagnétique entre la spire et la charge, fait que la paroi est constituée de l'assemblage d'éléments longitudinaux par leurs faces transversales, à la façon des douves d'un tonneau, avec un joint isolant électrique entre deux éléments adjacents.The cylindrical wall of such crucibles is subjected to significant overheating both because of the molten charge which it surrounds and as clearances by Joule effect due to the induced currents of which it is the seat. It is therefore important to limit these overheating by inserting cooling circuits inside the wall. However, the obligation to limit the currents induced in this same wall which, in addition to the thermal losses which they produce, also create an electromagnetic decoupling between the turn and the load, means that the wall consists of the assembly of longitudinal elements by their transverse faces, like a barrel stave, with an electrical insulating joint between two adjacent elements.

On voudrait restreindre autant que possible l'extension transversale de ces éléments, c'est-à-dire l'angle qu'ils embrassent, mais on est limité par les dimensions minimales des conduits de refroidissement.We would like to limit as much as possible the transverse extension of these elements, that is to say the angle that they embrace, but we are limited by the minimum dimensions of the cooling conduits.

La figure 1 représente en perspective et coupe partielle un de ces creusets déjà connus. L'inducteur 1 est une spire bobinée autour d'éléments longitudinaux 2 qui ont une section en forme de secteur de couronne qui embrasse un angle C'. Ils sont assemblés par leurs faces transversales 3 pour former la paroi cylindrique d'un creuset, qui comprend en outre un fond qui n'apparaît pas sur la figure. Des joints 4 en matériau isolant électrique sont interposés entre les éléments 2 adjacents et sont pressés entre les faces transversales 3.Figure 1 shows in perspective and partial section one of these crucibles already known. The inductor 1 is a turn wound around longitudinal elements 2 which have a section in the form of a crown sector which embraces an angle C '. They are assembled by their transverse faces 3 to form the cylindrical wall of a crucible, which further comprises a bottom which does not appear in the figure. Seals 4 of electrical insulating material are interposed between the adjacent elements 2 and are pressed between the transverse faces 3.

Les éléments 2 renferment chacun un circuit hydraulique de refroidissement qui est ici un conduit en U 5 qui s'étend sur toute leur longeur. Une de ses branches 6 communique avec un tuyau d'alimentation d'eau 8, l'autre branche 7 avec un tuyau d'evacuation d'eau 9. L'eau de refroidissement parcourt donc successivement les deux branches 6 et 7 du conduit en U 5.The elements 2 each contain a hydraulic cooling circuit which is here a U-shaped duct 5 which extends over all their length. One of its branches 6 communicates with a water supply pipe 8, the other branch 7 with a water discharge pipe 9. The cooling water therefore travels successively through the two branches 6 and 7 of the conduit in U 5.

Ici, les deux branches 6 et 7 sont situées sur la même circonférence, à mi-chemin des surfaces externe et interne de la paroi cylindrique du creuset. L'angle C' des éléments 2 doit donc être suffisant pour embrasser les deux branches ; il est ici de 24°, alors qu'on le souhaiterait aussi petit que possible.Here, the two branches 6 and 7 are located on the same circumference, halfway between the external and internal surfaces of the cylindrical wall of the crucible. The angle C 'of the elements 2 must therefore be sufficient to embrace the two branches; here it is 24 °, when we would like it to be as small as possible.

Le problème n'est pas fondamentalement différent si les deux branches sont placées à des profondeurs différentes de la paroi et sur le même rayon, ou si on remplace le conduit en U 5 par un conduit rectiligne vertical avec un tuyau d'alimentation en haut et un tuyau d'évacuation en bas. L'angle C' ne peut être que légèrement diminué par ces aménagements.The problem is not fundamentally different if the two branches are placed at different depths of the wall and on the same radius, or if we replace the U-shaped duct 5 by a vertical straight duct with a supply pipe at the top and a drain hose at the bottom. The angle C 'can only be slightly reduced by these arrangements.

L'invention permet de s'affranchir de ces inconvénients en surmontant le préjugé selon lequel les éléments 2 doivent être refroidis chacun par un circuit indépendant. Elle montre qu'il est parfaitement possible de disposer des circuits de refroidissement circonférentiels et qui passent tour à tour par plusieurs éléments 2. Les joints 4 peuvent en effet parfaitement assurer l'étanchéité.The invention overcomes these drawbacks by overcoming the prejudice that the elements 2 must each be cooled by an independent circuit. It shows that it is perfectly possible to have circumferential cooling circuits which pass in turn through several elements 2. The seals 4 can indeed perfectly seal.

En conséquence, on peut réduire l'angle embrassé par les éléments 2 jusqu'à des valeurs inconnues auparavant, de l'ordre du degré. Les courants induits dans le creuset sont alors négligeables, et des gains d'énergie considérables en résultent.Consequently, the angle embraced by the elements 2 can be reduced to previously unknown values, of the order of a degree. The currents induced in the crucible are then negligible, and considerable energy savings result.

L'invention concerne donc un creuset en matériau conducteur électrique de four à induction se composant d'éléments longitudinaux assemblés entre eux selon leurs faces transversales par l'intermédiaire de joints isolants électriques, caractérisé en ce que les éléments sont percés de conduits débouchant sur leurs faces transversales et débouchant sur des conduits analogues des éléments auxquels ils sont assemblés, et en ce que les joints sont étanches à des liquides de refroidissement parcourant les conduits.The invention therefore relates to a crucible made of an electrically conductive material of an induction furnace consisting of longitudinal elements assembled together according to their transverse faces by means of electrical insulating joints, characterized in that the elements are pierced with conduits leading to their transverse faces and leading to similar conduits of the elements to which they are assembled, and in that the joints are impervious to coolants passing through the conduits.

Cette invention va à présent être décrite à l'aide des figures annexées dont l'énumération suit, et qui sont données à titre illustratif et nullement limitatif :

  • la figure 1, déjà décrite, représente un creuset selon l'art antérieur ;
  • la figure 2A représente un creuset selon l'invention ;
  • la figure 2B représente un détail de la figure 2A ;
  • les figures 3, 4 et 5 représentent trois réalisations particulières de l'invention.
This invention will now be described with the aid of the appended figures, the list of which follows, which are given by way of illustration and in no way limitative:
  • Figure 1, already described, shows a crucible according to the prior art;
  • FIG. 2A represents a crucible according to the invention;
  • Figure 2B shows a detail of Figure 2A;
  • Figures 3, 4 and 5 show three particular embodiments of the invention.

L'inducteur 1 des figures 2A et 2B est le même que sur la figure précédente, et on retrouve des éléments longitudinaux 12 en forme de secteurs de couronne qui embrassent un angle C très inférieur à l'angle C' de la figure 1 : environ un ou deux degrés. On voit que les éléments 12 ont alors une épaisseur plus importante que leur largeur entre leurs faces transversales 13, ce qui fait que les courants induits par l'inducteur 1 ne peuvent s'y développer et que les pertes électromagnétiques, de même que l'échauffement qu'ils produisent par effet Joule, sont très réduits. En effet, des joints isolants électriques 14 sont interposés comme précédemment entre des éléments longitudinaux 12 adjacents.The inductor 1 of FIGS. 2A and 2B is the same as in the previous figure, and there are longitudinal elements 12 in the form of crown sectors which embrace an angle C much less than the angle C 'in FIG. 1: approximately one or two degrees. It can be seen that the elements 12 then have a greater thickness than their width between their transverse faces 13, which means that the currents induced by the inductor 1 cannot develop there and that the electromagnetic losses, as well as the heating which they produce by Joule effect, are very reduced. Indeed, electrical insulating joints 14 are interposed as before between adjacent longitudinal elements 12.

La principale différence de structure avec la figure 1 est que des conduits circonférentiels 15, étagés sur la hauteur des éléments 12, traversent ces derniers et débouchent sur leurs faces latérales 13 où ils se raccordent aux conduits 15 correspondants des éléments 12 adjacents pour former un réseau hydraulique global de refroidissement. Bien entendu, les joints 14 doivent être percés en face des conduits 15, et en même temps empêcher des fuites entre le réseau de refroidissement et l'extérieur, c'est-à-dire assurer l'étanchéité.The main structural difference with FIG. 1 is that circumferential conduits 15, stepped over the height of the elements 12, pass through the latter and open on their lateral faces 13 where they are connected to the corresponding conduits 15 of the adjacent elements 12 to form a network. overall hydraulic cooling. Of course, the seals 14 must be drilled in front of the conduits 15, and at the same time prevent leaks between the cooling network and the outside, that is to say seal.

La figure 3 représente une exécution possible de l'invention. La paroi du creuset est coupée diamétralement. Les éléments 12 présentent un talon inférieur 16 qui se présente sous forme d'une saillie 17 de leur surface externe et d'un rentrant 18 de leur surface interne. Le réseau de refroidissement constitué des canaux 15 forme ici deux hélices imbriquées 15' et 15" dont chacune débouche à son extrémité inférieure dans une boîte à eau cylindrique d'alimentation 19 sur laquelle les rentrants 18 s'emboîtent, et à son extrémité supérieure dans une boîte à eau cylindrique d'évacuation 20 qui s'emboîte autour du rebord supérieur 21 des éléments 12.Figure 3 shows a possible embodiment of the invention. The wall of the crucible is cut diametrically. The elements 12 have a lower heel 16 which is in the form of a projection 17 of their external surface and of a reentrant 18 of their internal surface. The cooling network made up of the channels 15 here forms two nested propellers 15 ′ and 15 ", each of which opens at its lower end into a cylindrical supply water box 19 on which the reentrants 18 fit together, and at its upper end in a cylindrical drainage water box 20 which fits around the upper edge 21 of the elements 12.

La boîte à eau d'évacuation 20 s'appuie sur le rebord supérieur 22 d'un anneau d'enrobage 23 disposé autour des éléments 12 et qui s'appuie lui-même sur les saillies 17. Il est en isolant électrique tel que la fibre de verre.The drainage water box 20 is supported on the upper edge 22 of a coating ring 23 disposed around the elements 12 and which is itself supported on the projections 17. It is electrically insulating such that the fiberglass.

Les boîtes à eau 19 et 20, ainsi que l'anneau d'enrobage 23, assurent donc la solidarisation mécanique des éléments longitudinaux 12.The water boxes 19 and 20, as well as the coating ring 23, therefore ensure the mechanical joining of the longitudinal elements 12.

Un fond 24 en matériau réfractaire, pourvu d'un orifice d'évacuation 25 de la charge fondue, complète le dispositif. Il est placé au milieu de la boîte à eau d'alimentation 19, dans l'espace qu'elle délimite.A bottom 24 made of refractory material, provided with an outlet orifice 25 for the molten charge, completes the device. It is placed in the middle of the supply water box 19, in the space which it delimits.

Bien entendu, les conduits 15 peuvent former un nombre quelconque d'hélices, qui n'est limité que par des raisons de facilité de construction.Of course, the conduits 15 can form any number of helices, which is only limited by reasons of ease of construction.

La figure 4 représente une autre réalisation possible de l'invention, qui diffère de la précédente en ce que le circuit hydraulique est formé cette fois de plusieurs canaux horizontaux 30 qui s'étendent chacun sur une circonférence de la paroi cylindrique. On prévoit alors un élément longitudinal 32 de forme particulière, éventuellement de plus grande extension angulaire que les autres, dont la section est en forme de H et qui comprend ainsi un paroi interne 33, une paroi externe 34 et une traverse 35 médiane reliant les deux parois 33 et 34. La traverse sépare deux canaux verticaux 36 et 37 ; l'un d'eux 36, à droite sur le dessin, est parcouru par l'eau de refroidissement arrivant d'un tuyau d'alimentation 38 et distribue cette eau dans les canaux horizontaux 30 ; l'autre, 37, à gauche sur le dessin, collecte et rassemble l'eau qui a parcouru les canaux horizontaux 30 avant de l'évacuer par un tuyau d'évacuation 39.FIG. 4 represents another possible embodiment of the invention, which differs from the previous one in that the hydraulic circuit is formed this time of several horizontal channels 30 which each extend over a circumference of the cylindrical wall. A longitudinal element 32 of particular shape is then provided, possibly of greater angular extension than the others, the section of which is in the shape of an H and which thus comprises an internal wall 33, an external wall 34 and a median cross-member 35 connecting the two walls 33 and 34. The cross-piece separates two vertical channels 36 and 37; one of them 36, on the right in the drawing, is traversed by the cooling water arriving from a supply pipe 38 and distributes this water in the horizontal channels 30; the other, 37, on the left in the drawing, collects and collects the water which has passed through the horizontal channels 30 before drain it through a drain hose 39.

Un avantage particulier de l'invention apparaît sur la figure 5. Avec les conceptions de l'art antérieur, il n'est pas possible de refroidir correctement des parties rétrécies de creuset. Par contre, des éléments longitudinaux 42 présentant une partie supérieure cylindrique 43 se raccordant à une partie inférieure 44 s'élargissant vers le bas par l'intérieur peuvent parfaitement être envisagés : le volume occupé par la charge fondue est alors cylindro-conique avec la pointe du cône en bas et il débouche sur un goulot de vidange 45 de petit diamètre délimité par les parties inférieures 44. Ces éléments longitudinaux 12 présentent une largeur beaucoup plus réduite près du goulot de vidange 45. Il est toutefois possible de les refroidir à cet endroit en augmentant progressivement la largeur (dimension radiale) de la section des conduits de refroidissement 15 pour ceux situés vers le bas.A particular advantage of the invention appears in Figure 5. With the designs of the prior art, it is not possible to properly cool shrunk crucible parts. On the other hand, longitudinal elements 42 having a cylindrical upper part 43 connecting to a lower part 44 widening downwards from the inside can perfectly be envisaged: the volume occupied by the molten charge is then cylindro-conical with the point of the cone at the bottom and it leads to a drain neck 45 of small diameter delimited by the lower parts 44. These longitudinal elements 12 have a much narrower width near the drain neck 45. It is however possible to cool them at this location by gradually increasing the width (radial dimension) of the section of the cooling conduits 15 for those located downwards.

La disposition des conduits 15 en canaux traversants présente donc un double intérêt : on peut soit réduire les pertes dans le creuset en le construisant avec des éléments plus fins et nombreux, soit assurer le refroidissement de zones rétrécies.The arrangement of the conduits 15 in through channels therefore presents a double advantage: it is possible either to reduce the losses in the crucible by constructing it with thinner and numerous elements, or to ensure the cooling of narrowed zones.

Bien entendu, on peut concevoir de nombreuses autres formes et constitutions de ces canaux de refroidissement sans sortir du cadre défini par les revendications.Of course, one can conceive of many other forms and constitutions of these cooling channels without departing from the scope defined by the claims.

Claims (5)

  1. Crucible made from electrically conductive material of an induction furnace comprising longitudinal elements (12; 22, 32, 42) assembled together in accordance with their transverse face (13) via electrically insulating joints (14), characterized th that the elements are pierced by ducts (15) issuing on to their transverse face (13) and onto identical ducts of the elements with which they are assembled and in that the joints (14) are tight to the cooling liquids passing through the ducts (15).
  2. Crucible made of an electrically conductive material for an induction face according to claim 1, characterized in that the ducts (15) form at least one helix within the crucible.
  3. Crucible made from electrically conductive material of an induction face according to claim 1, characterized in that the ducts (15) form parallel rings (30) within the crucible, each traversed by a longitudinal supply pipe (36) and a longitudinal discharge pipe (37).
  4. Crucible made from electrically conductive material for an induction face according to claim 1, characterized in that the distance between the transverse faces (13) of the elements is smaller than the crucible thickness.
  5. Crucible made from electrically conductive material for an induction face according to claim 1, characterized in that the crucible has a narrowed part (45).
EP88402505A 1987-10-06 1988-10-04 Crucible for an induction furnace Expired - Lifetime EP0311506B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8713778A FR2621387B1 (en) 1987-10-06 1987-10-06 INDUCTION OVEN CRUCIBLE
FR8713778 1987-10-06

Publications (2)

Publication Number Publication Date
EP0311506A1 EP0311506A1 (en) 1989-04-12
EP0311506B1 true EP0311506B1 (en) 1993-04-21

Family

ID=9355552

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88402505A Expired - Lifetime EP0311506B1 (en) 1987-10-06 1988-10-04 Crucible for an induction furnace

Country Status (5)

Country Link
US (1) US4873698A (en)
EP (1) EP0311506B1 (en)
JP (1) JP2660018B2 (en)
DE (1) DE3880416T2 (en)
FR (1) FR2621387B1 (en)

Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3910777C2 (en) * 1989-04-04 2001-08-09 Ald Vacuum Techn Ag Induction furnace with a metal crucible
DE3940029C2 (en) * 1989-12-04 1994-04-14 Leybold Ag Crucibles for induction heating
US5550353A (en) * 1990-01-31 1996-08-27 Inductotherm Corp. Induction heating coil assembly for prevent of circulating current in induction heating lines for continuous-cast products
US5257281A (en) * 1990-01-31 1993-10-26 Inductotherm Corp. Induction heating apparatus and method
US5272720A (en) * 1990-01-31 1993-12-21 Inductotherm Corp. Induction heating apparatus and method
US5272718A (en) * 1990-04-09 1993-12-21 Leybold Aktiengesellschaft Method and apparatus for forming a stream of molten material
US5090022A (en) * 1990-05-21 1992-02-18 Inductotherm Corp. Cold crucible induction furnace
DE4022561C1 (en) * 1990-07-16 1992-02-27 Forschungszentrum Juelich Gmbh, 5170 Juelich, De
FR2665249A1 (en) * 1990-07-26 1992-01-31 Dauphine Ets Bonmartin Laminoi Furnace for smelting by induction in a cold crucible
DE4102101C2 (en) * 1991-01-25 2003-12-18 Ald Vacuum Techn Ag Device for producing powders from metals
DE69211446T2 (en) * 1991-03-05 1997-01-02 Commissariat Energie Atomique CONTINUOUS MELTING FURNACE FOR OXIDE BULK, USING DIRECT HIGH-FREQUENCY INDUCTION, WITH VERY SHORT REFINING TIMES AND LOW ENERGY CONSUMPTION
DE4115278A1 (en) * 1991-05-10 1992-11-12 Abb Patent Gmbh MAGNETIC CONCLUSION FOR AN INDUCTION POT
JP3287031B2 (en) * 1991-10-16 2002-05-27 神鋼電機株式会社 Cold wall induction melting crucible furnace
US5160532A (en) * 1991-10-21 1992-11-03 General Electric Company Direct processing of electroslag refined metal
DE69125837T2 (en) * 1991-11-12 1997-11-06 Compuprint Spa Electrophotographic printer with improved properties for printed images
JP2967092B2 (en) * 1991-12-20 1999-10-25 科学技術庁金属材料技術研究所長 Floating melting equipment
JP3047056B2 (en) * 1992-06-02 2000-05-29 科学技術庁金属材料技術研究所長 Floating melting apparatus and its operation method
DE4320766C2 (en) * 1993-06-23 2002-06-27 Ald Vacuum Techn Ag Device for melting a solid layer of electrically conductive material
DE4429340C2 (en) * 1994-08-18 2003-04-30 Ald Vacuum Techn Ag Crucibles for inductive melting or overheating of metals, alloys or other electrically conductive materials
US5992503A (en) * 1995-12-21 1999-11-30 General Electric Company Systems and methods for maintaining effective insulation between copper segments during electroslag refining process
US6192969B1 (en) 1999-03-22 2001-02-27 Asarco Incorporated Casting of high purity oxygen free copper
KR101307745B1 (en) * 2012-02-14 2013-09-11 한국수력원자력 주식회사 Co0ling flow improved cold crucible

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE886353C (en) * 1941-09-04 1953-08-13 Vacuumschmelze Ag Base plate for induction ovens, especially for coreless induction ovens
DE866353C (en) * 1943-02-13 1953-02-09 Dortmunder Union Brueckenbau A Dismountable bridge
GB1118505A (en) * 1966-01-28 1968-07-03 Standard Telephones Cables Ltd Improvements in or relating to apparatus for the heat treatment of electrically conductive materials
FR1492063A (en) * 1966-04-05 1967-08-18 Commissariat Energie Atomique Further development of high frequency electric furnaces for the continuous production of electro-cast refractories
FR2036418A5 (en) * 1969-03-13 1970-12-24 Commissariat Energie Atomique
DE2110037C3 (en) * 1971-03-03 1980-05-14 Gebr. Happich Gmbh, 5600 Wuppertal Cover strip for clipping onto frames or bars, in particular in the interiors of vehicles
FR2497050A1 (en) * 1980-12-23 1982-06-25 Saphymo Stel COLD CAGE DIRECT INDUCTION FUSION DEVICE WITH ELECTROMAGNETIC CONTAINMENT OF MOLTEN LOAD
FR2531062A2 (en) * 1981-11-06 1984-02-03 Saphymo Stel Device for melting, by direct induction, dielectric substances of the glass or enamel type.

Also Published As

Publication number Publication date
US4873698A (en) 1989-10-10
FR2621387A1 (en) 1989-04-07
JP2660018B2 (en) 1997-10-08
DE3880416T2 (en) 1993-10-14
FR2621387B1 (en) 1990-01-05
JPH01118089A (en) 1989-05-10
EP0311506A1 (en) 1989-04-12
DE3880416D1 (en) 1993-05-27

Similar Documents

Publication Publication Date Title
EP0311506B1 (en) Crucible for an induction furnace
EP0119502B1 (en) Thermoelectric plant
EP0869571B1 (en) Temperature control device for a battery of electrochemical generators
FR2489208A1 (en) ELECTRICAL WELDING SLEEVE IN THERMOPLASTIC MATERIAL FOR JOINING PIPES IN THERMOPLASTIC MATERIAL
WO2003067166A2 (en) Core-type furnace
FR2544918A1 (en) SPRAY REFRIGERATION DEVICE FOR POWER SEMICONDUCTOR ELEMENTS
EP0232436B1 (en) Generator of molecular beams by thermal decomposition for the production of semiconductors by epitaxial deposition
EP0012672B1 (en) Device for the detachable mounting of an electric resistance heating element in the pressurizer of a nuclear reactor
EP0908997A1 (en) Sealed protection device for high voltage cable connection
EP0004492B1 (en) Microwave tube containing a delay line cooled by a circulating fluid
WO2014176706A1 (en) Method for producing a heating cable and heating cable produced according to this method
FR2494038A1 (en) CATHODIC RAY TUBE WITH HERMETICALLY INDEPENDENT FIXER HOLDER
FR2716521A1 (en) Angled joint for gas-insulated high tension transmission lines used to power electric transport vehicle
CH616610A5 (en)
BE1000218A6 (en) Tube insulation piece to be incorporated in a pipeline for discharging a high potential power.
WO2007031564A1 (en) Melting furnace with single-turn inductive device consisting of a plurality of conductors
FR2472727A1 (en) SOLAR ENERGY SENSOR IN GLASS AND DOUBLE WALL
EP0232661B1 (en) Electromagnetic pump for conductive liquid with backflow by means of magnetic repulsion
WO2008001014A1 (en) Electric feedthrough structure for superconductor element
WO2012127152A1 (en) Induction furnace crucible
FR2473688A1 (en) Solar heat collector with monophase heat transfer fluid - has walls defined by tube coiled around imaginary partial sphere and uses parabolic mirror to focus radiation
FR2566101A1 (en) Electrical water heater
FR2680566A1 (en) Plate exchanger
FR2548856A1 (en) Device for fusion by direct induction in a segmented cold cage
CA1136196A (en) Electromagnetic pumps for liquid metal

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): CH DE GB IT LI

17P Request for examination filed

Effective date: 19890915

ITF It: translation for a ep patent filed

Owner name: JACOBACCI & PERANI S.P.A.

17Q First examination report despatched

Effective date: 19920703

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): CH DE GB IT LI

REF Corresponds to:

Ref document number: 3880416

Country of ref document: DE

Date of ref document: 19930527

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 19930708

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Effective date: 19931031

Ref country code: CH

Effective date: 19931031

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19951019

Year of fee payment: 8

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19970701

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20001004

Year of fee payment: 13

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20011004

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20011004

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 20051004