US3589434A

US3589434A - Installations for electrically remelting metals

Info

Publication number: US3589434A
Application number: US773424A
Authority: US
Inventors: Otmar Kleinhagauer; Wolfgang Holzgruber
Original assignee: Individual
Current assignee: Individual
Priority date: 1967-11-06
Filing date: 1968-11-05
Publication date: 1971-06-29
Anticipated expiration: 1988-06-29

Abstract

An installation for electrically remelting a metal so that molten metal achieved in this way from a suitable electrode can be given a predetermined configuration in a mold. The molten metal in the mold is maintained at its elevated temperature during changing of a primary electrode by way of a secondary electrode, and a pair of carriage means are provided for respectively supporting these electrodes. One transporting means is operatively connected with the carriage means which supports the primary electrode to displace the latter away from the mold when it becomes necessary to exchange an at least partially consumed primary electrode with a new primary electrode. The secondary electrode supporting carriage and the mold form a pair of units one of which is acted upon by a second transporting means for displacing these units with respect to each other in such a way that when the primary electrode is displaced away from the mold the secondary electrode and mold coact with each other to maintain the molten metal at its elevated temperature, while the secondary electrode is maintained normally at an inoperative position displaced from the mold during the normal operations when the primary electrode coacts with the mold to supply the molten metal to the latter.

Description

United States Patent (72] Inventors Otmar'Klelnhaga'uer Albert Bohlerasse Noll; Wolfgang llolzgruber, Peter Tannerstrasse 16, both of Kaplenberg, Austria [21 Appl. No. 773,424 {22] Filed Nov. 5, 1968 [45] Patented June 29, 1971 [32] Priority Nov. 9, 1967, Nov. 6, 1967 [33] Austria [31 10,006/67 and A9954/67 I [54] INSTALLATIONS FOR ELECTRICALLY REMELTING METALS 10 Claims, 5 Drawing Figs. [52] U.S. Cl. 164/252, 13/9, 164/273 [51] Int. Cl. 822d 27/02 [50] Field of Search 164/50, 52, 250, 252; 13/9 US,14 US, 31

I [56] References Cited I UNITED STATES PATENTS RE 12.658 3/1903 Heroult 13/9 2,191,481 2/1940 Hopkins 164/52 3,152,372 10/1964 Hopkins 164/52 3,404,209 10/1968 I Brooke... l3/9-X 2,984,876 5/1961 Garmy 164/252 Priniary Examiner- Robert D. Baldwin Assistant Examiner-R. Spencer Annear Attorney-Arthur O. Klein ABSTRACT: An installation for electrically remelting a metal so that molten metal achieved in this way from a suitable electrode can be given a predetermined configuration in a mold. The molten metal in the mold is maintained at its elevated temperature during changing of a 'primary electrode by way of a secondary electrode, and a pair of carriage means are provided for respectively supporting these electrodes. One transporting means is operatively connected with the carriage means which supports the primary electrode to displace the latter away from the mold when it becomes necessary to exchange an at least partially consumed primary electrode with a new primary electrode. The secondary electrode supporting carriage and the mold form a pair of units one of which is acted upon by a second transporting means for displacing these units with respect to each other in such a way that when the primary electrode is displaced away from the mold the secondary electrode and mold coact with each other to maintain the molten metal at its elevated temperature, while the secondary electrode is maintained normally at an inoperative position displaced from the mold during the normal operations when the primary electrode coacts with the mold to supply the molten metal to the latter.

PATENTEU JUN29 1971 SHEET 1 0F 5 lave/liars; OTMAR mm GAVER VOLFGANG HOLIGRVBE R MWQW T H F I. w

PATENTEDJUNZQIQYI SHEET 3 BF 5 Inventors;

DTMA-R KLEIMHAa WE R A l'nR All Y INSTALLATIONS FOR ELECTRICALLY REMELTING METALS- I BACKGROUND OF THE INVENTION The present invention relates to installations for electrically remelting metals, and in particular a metal such as steel, by providing for use in the installation a primary electrode madeup of the metal which is to be remelted. A mold receives the molten metal from the primary electrode to shape the molten metal into a body of a given configuration, and when it becomes necessary to exchange an at least partly consumed primary electrode for a new electrode, a secondary electrode is provided to maintain the molten metal within the mold at the required elevated temperature until the new primary electrode can be placed in an operative position resuming the normal operations.

In conventional installations of this latter type, the mold and the primary and secondary electrodes are respectively supported by carriages capable of being displaced vertically by way of suitable cable-and-pulley assemblies which coact with these carriages. When, during the remelting of the primary electrode, as a result of the heat which is electrically generated, this primary electrode becomes consumed to such as extent that onlya short residual length thereof remains, it becomes necessary to raise the carriage which supports the primary electrode to displace the latter away from the mold, and then the consumed primary electrode is replaced with a new primary electrode. This new primary electrode is then lowered as a result of the lowering of the carriage which supports the same to situate the new primary electrode at an operative location with respect to the mold so as to continue the remelting and the molding operations.

With such an arrangement it is essential to prevent cooling and solidifying of the molten metal in the mold during the time when an at least partially consumed primary electrode is being exchanged for a new primary electrode. In order to maintain the temperature of the molten metal in the mold at the required value during this period of exchange of the primary electrode, a secondary electrode is provided, this secondary electrode being connected into the electrical circuit and coacting with the mold to maintain the molten metal therein at the required elevated temperature until the new primary electrode is in a position to continue with the operations. Known secondary electrodes surround the primary electrode and are, for example, of a spiral-shaped configuration or have the configuration of a pipe or tube surrounding the primary electrode. However, when with such known installations it is required to provide equipment of relatively large dimensions in order to remelt the metal, there is the disadvantage that the secondary electrode which surrounds the primary electrode, during the removal of the residual length of the consumed primary electrode and replacement thereof with a new electrode, interferes to a very large extent and in a most undesirable manner with the operations which must be carried out, so that the exchange of a consumed primary electrode for a new primary electrode can only take place with considerable difficulty.

SUMMARY OF THE INVENTION It is accordingly a primary object of the present invention to provide installation which will avoid the above drawbacks.

In addition, it is an object of the invention to provide an installation which makes it possible not only to easily exchange an at least partly consumed primary electrode for a new electrode, but which also can be arranged in such a way as to adapt itself to the particular space conditions which obtain. Thus, it is an object of the invention to provide not only an installation for conditions where very large space is freely available, but also an installation which can be used under conditions where only a limited space is available, while at the same time assuring an exceedingly simple, rapid exchange of an at least partly consumed primary electrode with a new primary electrode in-such a manner that the secondary electrode does not in any way interfere with the exchange operations.

Yet another object of the present invention is to provide an installation of the above type which is of an extremely simple construction while at the same time being capable of use in installations of particularly large dimensions.

With the structure of the invention a mold means receives the primary electrode during the normal operation of the installation, and a primary electrode carriage means support the primary electrode. A secondary electrode carriage means supports a secondary electrode, and a first transporting means is operatively connected with the primary electrode carriage means to displace the latter for moving an at least partly consumed primary electrode away from the mold means in order to enable the latter electrode to be conveniently replaced with a new primary electrode. The mold means and the secondary electrode carriage means form a pair of units which are displacable one with respect to the other to locate the secondary electrode at an operative location with respect to the mold means during the time when the exchanging operations in connection with the primary electrode are going forward. A second transporting means is operatively connected with one of these units for transporting the one unit with respect to the other to bring about on the one hand the operative relationship between the secondary electrode and mold means during exchange of a primary electrode and on the other hand to bring about displacement of the secondary electrode to an inoperative location where it does not participate in the operations during the time when the primary electrode coacts with the mold means in connection with the normal remelting of the metal and molding thereofin the mold means.

The first transporting means is capable of transporting the primary electrode carriage means not only vertically but also horizontally. This first transporting means may, for example, take the form of a horizontally movable crane carriage from which is suspended a column on which the primary electrode carriage means is vertically movable. However, in those situations where a sufficient space is not available for such a horizontally movable crane structure, the column which supports the primaryelectrode carriage means can simply be itself supported for swinging movement about its axis, so that through a suitable drive after the primary electrode carriage means has been elevated to displace the primary electrode out of the mold, the column which supports the primary electrode carriage means can be swung about its axis to horizontally move the at least partly consumed primary electrode to a location where it can conveniently be exchanged for a new primary electrode.

BRIEF DESCRIPTION OF DRAWINGS The invention is illustrated by way of example in the accompanying drawings which form part of this application and in which:

FIG. 1 is a fragmentary schematic elevation showing one embodiment of an installation of the invention for the remelting of a metal such as steel;

FIG. 2 is a fragmentary plan view of the structure of FIG. 1;

fig. 3 is a schematic elevation of another embodiment of an installation of the invention for the electric remelting of a metal such as steel;

FIG. 4 is a plan view of the structure of FIG. 3; and

FIG. 5 is a side view of part of the structure of FIG. 4 taken along line A-B of FIG. 4 and showing this part of the structure as viewed in the direction of the arrow C of FIG. 4, FIG. 5 showing that part of the structure which is used in connection with situation of a new primary electrode on the primary electrode carriage.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring first to the installation illustrated in FIGS. 1 and 2, it will be seen that the mold 10 has an inner cylindrical wall 1 l and at the region of it upper end a pair of opposed arms 14 and 17 which extend laterally from the mold 10. This is a continuous castinginstallation with the mold 10 having upper and lower open ends so that duringrelatively slow upward movement of the mold, molten metal therein solidifies sufficiently to be self-sustaining when the mold moves upwardly beyond the solidified metal, so that in this way the mold continuously uncovers a building column of metal which becomes exposed beneath the upwardly moving mold in a well-known manner.

The mold 10 thus forms a mold means for molding the molten metal to a body of a given configuration, and this mold means l is carried by a mold carriage means 20 which has a pair of arms 21 and 23 respectively extending beneath and engaging the arms 14 and 17 so that through the supporting of the arms 14 and, 17 the entire mold means is carried by the mold carriage means 20. This carriage means is vertically movable along a stationary vertical column of square cross section. A cable is connected at its lower end to the carriage 20 for controlling the elevation thereof, and this cable 40 is wound around a cable winch or drum 41. Thus, the turning of the drum 41 will result in raising or lowering carriage 20.

The molten metal is derived from the remelting of an clongated primary electrode of cylindrical configuration, this primary electrode 50 being fixed at its upper end to a bar extension 51 made of the same material as the primary electrode 50. A primary electrode carriage means is provided to support the primary electrode 50, anda column 70 which is also of noncircular cross section, such as a square cross section, coacts with the carriage 60 to guide the latter for vertical movement along the column 70.

The arm 61 of the primary electrode carriage means 60 is formed at its end region which is distant from the column 70 with a longitudinal slot 62 through which the upper region of the bar'extension 51 passes. This extension 51 terminates at its top end in an outwardly directed flange or collar 52 overlapping and resting directly on the arm 61 so that in this way downward falling of the primary electrode 5.0 is prevented. ln addition, a pair of plates 63 are carried by the arm 61 on opposite sides of the slot 62 thereof, and these plates'are respectively formed with substantially semicircular recesses 63' respectively receiving opposed portions of the flanges or collar 52, so that in this way longitudinal shifting of the bar 51 along the slot 62 is avoided. 1

A transporting means is operatively connected with the carriage means 60 for displacing'the lattervertically along the column 70 and also for displacing the carriage means 60 horizontally together with the column 70. This transporting means includes, in the illustrated example, a crane carriage 80 which extends across and rides on the rails 101 respectively carried by the lbeams 100, this carriage 80 itself having a pair of elongated channel members 82 extending transversely across and between the rails 101. The column 70 is directly connected with and hangs down from the horizontal channels 82.

A cable means coacts with the carriage means 60 for controlling the elevation of the latter along the vertical column 70, and this cable means includes a pair of cables 90 respectively situated on opposite sides of the carriage means 60, the cables 90 being respectively wound onto winches or drums 91 which are turned to raise or lower the carriage means 60. The cables 90 are respectively guided around pulleys or rollers 64 supported for rotary movement at the opposite sides of the carriage 60 and carried by the latter, these guide rollers or pulleys 64 respectively being formed with grooved peripheries which receive the cables 90, respectively. Each cable 90 is fixed at one of its ends to a holder 83 at one of the channels 82, while the other ends of the cables are respectively fixed to the cable drums 91. These drums are respectively fixed to the output shaft portions 93 of an output shaft of the drive transmission 92 which is self-retarding. The elevation of the primary electrode carriage means 60 and thus of the primary electrode 50 carried thereby, can be controlled by way of the electric motor 96 which also is carried by the crane carriage 80, this motor 96 being operatively connected through an elastic clutch or coupling 95 with the input drive shaft 94 of the transmission 92, so as to drive theshaft 94 and thus transmit the drive through the transmission 92 to the cable drums.

ln order to assure an easy vertical movement of the carriage means 60 along the column 70, the carriage 60 is provided at its four walls which define the opening through which the column 70 extends with rollers 66, four rollers 66 being respectively supported for rotary movement by four supports 65 carried by each of the inner surfaces of each of the four walls of the carriage 60, so that by engagement of these freely turnable rollers with the flat surfaces 71' of the column 70, which is of square cross section, an easy vertical movement of the carriage 60, with relatively low friction, along the column 70 is assured in response to turning of the winches 91. These winches turn together.

The carriage has a pair of wheels84 and a pair of wheels 86 all of which are formed with peripheral grooves which receive the rails 101. The wheels 84 are supported for free rotary movement on pins 85 which are fixed to the frame 81 of the carriage 80. The other wheels 86 are fixed to a rotary shaft 87. This shaft 87 is driven in rotation by way of an electric driving motor 89, carried by the frame 81 and transmitting the drive to the shaft 87 through a chain and sprocket transmission 88. Thus, the operation of the drive from the motor 89 will result in horizontal movement of the crane carriage 80 along the rails 101 in a horizontal direction. Thus, the electric driving motor 89 together with the sprocket and chain transmission 88, the shaft 87 and the wheels 86 form the drive for moving the entire transporting means horizontally together with the primary electrode carriage means 60, while the electric motor 96 together with the elastic clutch or coupling and the transmission 92 through which the drive is transmitted to the drums 91 form a drive by way of which the crane functions to raise and lower the carriage means 60.

The secondary electrode means of this embodiment is composed of six parallel bars 111 which extend parallel to the primary electrode 50 and which are carried by a holding ring 112 which surrounds the primary electrode 50. These bars 111 which constitute the secondary electrode means can either be made of a material which has a higher melting point than the primary electrode 50 such as graphite, tungsten, or molybdenum, or the bars 111 may be made of the same material (steel, for example,), as the primary electrode 50. The several bars 111 are releasably fixed with clamps 113 carried by ring 112, by way of setscrews 114, so that in this way the bars 111 are replaceably connected with and carried by the ring 112. This ring 112 is in turn connected to and carried by the secondary electrode carriage means 115.

The secondary electrode carriage means 115 is located over the mold carriage means 20, and both of the latter carriage means are vertically movable along a fixed vertical column 30. A cable is connected at it bottom end to the carriage means 115 and is wound around a cable drum or winch 121, so that the turning of this winch will control the elevation of the carriage means 1 15.

The top end of the column 30 carries a pair of driving

motors

42 and 122 which respectively have their

output shafts

43 and 123 coaxially fixed with the cable drums 41 and 121, so that these motors may be operated to control the elevations of the

carriages

20 and 115, and thus control the elevations of the mold 10 and secondary electrode 110.

During the remelting of the primary electrode 50, the elevation of the latter with respect to the mold 10 is adjusted in such a way that on one hand the electrode 50 projects downwardly into the layer of slag 54 which floats on the surface of the molten metal to clean and shield the molten metal in this way, and thus the lower end of the electrode 50 can be situated at a selected distance from the surface of the molten metal. On the other hand, it is possible to maintain by proper vertical displacement of the

carriages

60 and 20 an unchanging relative position between the surface of the molten metal and the mold 10.

From one pole of the unillustrated source of current (in general the secondary winding of a transformer) comes an electrical conductor 130 which is connected to a switch 131 capable of selectively contacting one of the pair of contacts which are electrically connected with the

conductors

132 and 133 which are respectively connected electrically with the bar extensions 51 of the primary electrode 50 and the holding ring 112 of the secondary electrode 110. The other pole of the source of current is connected through the conductor 134 with a base plate 135, preferably made of copper, and the ingot or steel block 53 which builds upwardly during the progress of the continuous casting operation rests directly on the base plate 135. The plate 135 is in turn located on an insulating plate 136 which insulates the structure from the floor. As long as the primary electrode 50 extends into the layer of slag 54, the switch 131 is in a position providing electrical communication between the

conductors

130 and 132.

When it becomes necessary to raise the small residual portion of the primary electrode 50 out of the molded for the purpose of replacing the consumed primary electrode with a new primary electrode, the switch 131 is actuated, preferably automatically, so as to assume a position where the conductor 130 is placed in electrical connection with the conductor 133. At the same time the secondary electrode carriage means is lowered until the secondary electrode 110 has the bars 111 thereof extending into the layer of slag 54, with the lower ends of the bars 111 situated at the selected distance from the surface of the molten metal. Now the current will flow through the conductor 133 to the several bars 111 of the secondary electrode 110. The result is that the secondary electrode 110 maintains the molten metal at the elevated temperature required to prevent cooling of the molten metal, and in the case where the bars 111 are made of the same material as the primary electrode 50, these bars 111 melt so that the operations continue with the secondary electrode at this time.

As soon as the residual remaining portion of the electrode 50 which has previously been melted away has been raised away from the mold 10 by way of the structure which raises the carriage 60 along the column 70, so that the primary electrode becomes situated at an elevation higher than the holding ring 12 of the secondary electrode 110, the motor 89 is actuated to provide rotary movement of the shaft 87 and thus of rollers 86, to displace the crane carriage 80 horizontally, and in this way the residual part of the primary electrode 50 is transported to a location situated to one side of the installation, and at the latter location it is a simple matter to remove the residual part of the primary electrode from the carriage 60 and to deposit it on the floor. Now a previously prepared new primary electrode, situated beyond the mold 10 and the secondary electrode 110, and supported in a vertical position, is suspended from the arm 61 of the primary electrode carriage means 60. The new primary electrode 50 is then transported together with the carriage means 60 by return of the crane carriage 80 to its initial position so that the new primary electrode 50 can be lowered into the mold 10, the secondary electrode 110 can again be removed upwardly out of the mold 10, and the switch 131 can be returned to its initial position, preferably automatically, so that the normal operations can then go forward with the new primary electrode.

For the sake of completeness, it should be noted that the mold 10 is cooled by water. The water flows to the installation through a flexible hose 140 which delivers the water to a pipe 141 which in turn communicates with the passage 22 formed in the interior of the arm 21 of the mold carriage 20. From the hollow interior of the arm 21, the water flows to the interior of the arm 14 of the mold 10, the hollow interior 22 of the arm 21 communicating with the hollow interior of the arm 14 through a suitable seal. The hollow interior 15 of the arm 14 communicates with a space which is formed between the inner wall 11 and the outer wall 12 of the mold 10. Thus, from the arm 14 the cooling water will flow downwardly through the space 13, and from the lower end of the space 13 the cooling water reaches the conduit 16 to flow upwardly through the latter into the hollow interior 18 of the other arm 17 of the mold 10. The hollow interior 18 in turn communicates in a fl uidtight manner with the hollow interior 24 of the arm 23, so that the cooling water will flow through the hollow interior 24 of the arm 23. The interior of the arm 23 communicates with a pipe 142 which in turn communicates with the return flow hose 143, so that in this way cooling water is circulated through the mold.

It is furthermore to be noted that with the mold carriage means 20 and the secondary electrode carriage means 115, in a manner analogous to the primary electrode carriage means 60, there are at each of the four inner surfaces which respectively confront the exterior flat surfaces of the column 30 four freely rotatable rollers supported by suitable pins in order to assure that the mold carriage means 20 and the secondary electrode carriage means are easily movable vertically along the column 30.

With the installation which is illustrated in FIGS. 35, the mold means 200 is also of a cylindrical configuration and has an inner cylindrical wall 20l-and in the region of its upper end a pair of opposed outwardly directed

arms

204 and 207 which respectively rest in a fluidtight manner on the

arms

211 and 213 of the mold carriage means 210. This mold carriage means 210 is supported for a vertical movement along the vertical column 220 which is of a noncircular cross section, which in this case is rectangular, and the elevation of the carriage 210 is controlled by way of a cable 230 wound onto a winch or cable drum 231. The cable 230 is guided around a roller or cable pulley 21S supported for free rotary movement directly on the carriage 210. One end of the cable 230 is fixed by way of a fastening device 222 to the support plate 221 which is fixedly mounted on the top end of the column 220. The other end of the cable 230 is fixed to the drum 231.

' The primary electrode 240 which forms the metal which is to be remelted is provided at its upper end with a bar extension 241, the primary electrode 240 also being of a cylindrical configuration in this case. By way of the bar extension 241 the primary electrode 240 is supported on the primary electrode carriage means 250 which is supported for movement along the vertical column 260 which is of a rectangular cross section. The carriage 250 has an arm 251 formed at its end distant from the column 260 with a longitudinal slot 252 which receives the bar extension 241 of the primary electrode 240. The top end of the extension 241 is provided with the flange or collar 242 which rest directly on the arm 251, and as may be seen from FIG. 4, the arm 251 carries on opposite sides of the slot 252 the plates 253 respectively formed with the substantially semicircular indentations 253 which receive opposed portions of the collar or flange 242, so that in this way the primary electrode cannot be shifted longitudinally along the slot 252.

The primary electrode carriage means 250 is provided at its opposite sides with a pair of freely turnable cable guide pulleys 254 formed with peripheral grooves which receive the cables 270 which are wound onto the cable drums or winches 271. Each ofthe cables 270 is fixed at one end by way ofa fastening structure 262 to the supporting plate 261 which is fixed to the top end of the column 260. The other ends of the cables 270 are respectively fixed with the drums or winches 271. The pair of cable drums 271 are respectively fixed coaxially with the ends 273 of a rotary shaft driven by a self-retarding drive 272 which is carried by the support plate 261. An electric motor 274 transmits the drive through the transmission 272 to the shaft 273 which thus rotates the drums 271, and in this way the elevation of the carriage 250 and thus of the primary electrode 240 is regulated.

With this installation there is a secondary electrode 280 shown in elevation at the left central portion of HO. 3 and having at its upper end a bar extension 281, this secondary electrode 280 also being of a cylindrical configuration and being made either of a material having a higher melting point than the primary electrode 240, such as, for example, graphite, tungsten, or molybdenum, or being made of the same material (steel, forexample as the primary electrode 240. This secondary electrode 280 is suspended from a secondary electrode carriage means 290 which is vertically movable along the column 220.

The secondary electrode 280 is mounted in the same way as the primary electrode 240. Thus, the arms 291 of the secondary electrode carriage means 290 is formed with a longitudinal slot 292 (FIG. 4) and the extension bar 281 of the secondary electrode 280 has at its top end the collar or flange 282 which rests on the top surface of the arm 291 and which is received in the substantially semicircular recesses 293 formed in the plates 293 which are fixed to the top surface of the arm 291.

The secondary electrode carriage means290 as well as the mold carriage means 210 situated therebeneath are both vertically movable along the column 220. The carriage means 290 has its elevation controlled by way of a cable 300 wound onto a cable drum 301. The carriage means includes an inner guide sleeve 296 which is vertically. movable along the column 220 and which supports for rotary movement, on a suitable pin, the cable guide roll orpulley 294. One end of the cable 300 is fixed by a fastening device 223 to the support plate 221 which is fixed to the top end of the column 220, while the other end of the cable 300 is fixed to the drum 301.

' The elevation of the mold carriage means 210, and thus of the mold 200 therewith, as well as the elevation of the secondary electrode carriage means 290 and the secondary electrode 280 carried thereby are regulated by way of

electric drive motors

232 and 302 respectively, which are fixedly mounted on the support plate 221. These drive motors respectively have output shafts 233 and 303 (FIG. 4) coaxially fixed with the

drums

231 and 301. Thus, by actuation of the

electric drive motors

232 and 302 it is possible to control the elevation of the

carriages

210 and 290 respectively.

Both of the

columns

220 and 260 have cylindrical journal pins 224 and 225 (for the column 220) and 236 and 264 (for the column 260), and these journals are supported for rotary movement in

bearings

310 and 320, for the

column

220, and 330 and 340, for the column 260. The bearing blocks 320 and 340 are fixed directly to the floor and act as thrust as well as radial bearings while the upper bearings arecarried by the frames 311'and 331 and act only as radial bearings.

The column 220 is adapted to swing the mold 200 away from the base plate 365 after first lifting it, so that the formed steel ingot 243 can be more easily removed from the base plate 365. At the upper side of each of .the

lower bearings blocks

320 and 340 are fixed a pair of ring gears 321 and 341, respectively, and these gears respectively mesh with

pinions

226 and 265, The

pistons

226 and 265 are respectively fixed to drive

shafts

228 and 267 which are the output shafts of

electric drive motors

227 and 266, respectively, these motors both being mounted on the

columns

220 and 260, as by being suitably keyed thereon. Thus, by way of the

electric drive motors

227 and 266 it is possible to turn the

columns

220 and 260 respectively about their axes.

Furthermore, it should be noted that the secondary electrode carriage means 290 includes a separate sleeve 296, already referred to above, which is movable along the column 220, while the arm 291 is angularly turnable about he sleeve 296 without being capable of shifting axially with respect thereto. The top edge of the rotary arm 291 fixedly carries a ring gear 295 which meshes with a pinion 350. This pinion 350 is fixed to and driven by the rotary shaft 352 of an electric drive motor 351 which is mounted directly on the sleeve 296, as by being suitably keyed thereto. Thus, by way of the electric driving motor 351 it is possible to rotate the arm 291 together with the secondary electrode 280 suspended therefrom about the axis of the column 220..

During the melting of the primary electrode 240, the elevation of the latter and the mold 200 are regulated in such a way that on the one hand the primary electrode extends into the layer of slag 244 which floats on the molten metal (to clean and shield the molten steel), and thus the lower end of the primary electrode can be situated at a selected distance from the surface of the molten metal. On the other hand, the position of the surface of the molten metal with respect to the mold 200 remains unchanged, inasmuch as the regulation is such that both the mold 200 and the surface of the molten metal rise simultaneously at the same rate during the operation of the installation.

From one pole of an unillustrated source of current (in general the secondary winding of a transformer) there is an electrical conductor 360 connected to the change-switch 361 capable of connecting the conductor 360 selectively either with the conductor 363 or with the conductor 362. The conductor 362 is electrically connected with the extension bar 241 of the primary electrode 240, while the conductor 363 is electrically connected with the bar extension 281 of the secondary electrode 280. The other pole of the unillustrated source of current is connected with the electrical conductor 364 which is connected with the base plate 365 on which the bottom end of the ingot or steel block 243 rests during the continuous casting operations. Below the base plate 365, which preferably is made of copper, is an electric insulating, intermediate plate 366 which in turn restsupon a suitable support 371. 1

As long as the primary electrode 240 extends into the layer of slag 244, the change switch 361 is in a position where the current flows from the conductor 360 to the conductor 362, so that in this way the primary electrode 240 is connected into the circuit and melts to form the molten metal. However, when the residual part of the primary electrode 240 becomes so short that it is necessary to withdraw it from the mold 200 for the purpose of replacing it with a new primary electrode, the switch 361 is automatically changed over to its other position, indicated in dotted lines in FIG. 3, where it will place the conductor 363 and the secondary electrode 280 in the circuit. Simultaneously, the primary electrode means 250 is moved upwardly to such an extent that the lower end of the residual part of the primary electrode 240 is situated above the upper edge of the mold 200.

When the lower end of the primary electrode 240 thus reaches an elevation above the upper edge of the mold 200, the column 260 and the arm 291 of the carriage 290 are both turned simultaneously in the same direction through an angle of approximately and the column 220 remains stationary at this time.' The turning of the column 260 is brought about by way of the motor 266 and the

gears

265 and 341, while the turning of the arm 291 is brought about by way of motor 351 and the coaction of the

gears

350 and 295. The result of this rotary movement is that on the one hand the residual part of the primary electrode 240 is swung away from the mold 200 and on the other hand the secondary electrode 280 is swung to location situated over the mold 200. Now the secondary electrode carriage means 290 is lowered to such an extent that the secondary electrode 280 extends into the slag bath 244 and has its lower end situated at the selected distance from the surface of the molted metal. Thus, the current will now flow through the conductor 363 to the secondary electrode 280. The result is that the secondary electrode 280 maintains the molten metal at its required elevated temperature and in fact melts to continue the supply of molten metal in the case where the secondary electrode is made of the same material as the primary electrode 240.

Simultaneously with this downward movement of the secondary electrode carriage means 290 there is also the downward movement of the primary electrode carriage means 250, and in this way the residual remaining part of the primary electrode 240 reaches the platform 370 where it can easily be removed from the primary electrode carriage means 250.

Referring now to FIG. 5, there is shown therein a primary electrode feeding device 380 which includes a swingable lever 381 of angular or bell crank configuration. This lever 381 is supported for swinging movement by a suitable pivot pin carried by a block 386. The lower lever arm 383 of the lever 381, which is inclined only to a slight extent with respect to a horizontal plane, fixedly carries at its upper surface a plate 384 on which a new primary electrode 240 has previously been placed so as to rest thereon in readiness to replace the of its opposed ends a pair of rings 385 which surround the new primary electrode 240.

As soon as the residual part of the previously consumed primary electrode 240 has been removed from the carriage 250, the lever 381 is swung with the aid of a pneumatic drive which includes a cylinder 389 and a piston 387 therein. The compressed air is delivered to the piston 387 to advance the latter to the left, as viewed in FIG. 5, with respect to the cylinder 389, so that the piston rod 388 swings the lever 381 in a counterclockwise direction, as viewed in FIG. 5, thus displacing the bar extension 241 into the longitudinal slot 252 which at this time is in alignment with the extension 241. In this way the new primary electrode 240 is placed in its vertical position with the collar or flange 242 situated above the plates 253. It is to be noted that the piston rod 388 is pivotally connected. with the lever 381 while the cylinder 389 is itself pivotally connected to a stationary sidewall 37] of the installation. The new primary electrode 240 is shown in its vertical position in dotdash line in FIG. 5.

When the carriage 250 is now raised, the flange 242 will be received in the recesses 253' of the plates 253. The raising of the primary electrode carriage means 250 takes place simultaneously with the raising of the secondary electrode carriage means 290 so that the new primary electrode 240 is raised simultaneously with the secondary electrode 280, and the raising of these electrodes is carried out to such an extentthat the lower ends of both electrodes are situated at an elevation higher than the upper'edge of the mold 200. The primary electrode 240 is shown in its raised position at this time in dot-dash lines at the right of FIG. 3. Now the column 260 is turned about its axis back to its initial position, by way of the

drive

266, 267, 265, 341 and simultaneously the arm 291 of the secondary electrode carriage means 290 is swung back to its initial position by way of the

drive

351, 352, 350, 295. Thus, these components are returned to their initial angular positions, and then the primary electrode carriage means 250 is lowered to such an extent that the new primary electrode 240 extends into the slag bath 244 and has its lower end situated at the selected distance from the surface of the molten metal. During the downward movement of the primary electrode 240 at this time, the change switch 361 is shifted, preferably in an automatic manner, back to its initial position, so that the current will now flow'to the primary electrode. Then the normal operations are repeated. At this time, which is to say at the resumption of the normal operations with the new primary electrode 240, a third primary electrode 240 is moved by way of a nonillustrated crane structure to the device 380 so as to be in readiness to replace the new-electrode 240 when the latter is consumed to such an extent that it must be changed. In order that the new primary electrode, during its downward movement at the device 380, will be smoothly guided through the rings 385 carried by the arm 382 of the lever 381, the openings of these rings flare outwardly in an upward direction, so that they are tapered downwardly to provide a smooth guiding of the new electrode through the rings 385.

As soon as the new primary electrode is mounted on the electrode-feeding device 380, the lever 381 is swung back by way of the pneumatic drive through the angle y shown in FIG. which preferably is on the order of and thus a new electrode is now in a position of readiness to replace the consumed electrode when required.

It should furthermore be noted, as shown in FIG. 4 that the angle 0: included between straight lines in a horizontal plane interconnecting the vertical center lines of the mold and the

columns

220 and 260, as well as the swing-angle ,8 of the primary electrode carriage means 250 and the arm 291 of the secondary electrode carriage means 290 are both preferably on the order of 90.

In the event that the secondary electrode 280 is made of the same material as the primary electrode 240, it is desirable to provide an unillustrated secondary'electrode feeding device which may be identical with the device 380 and which is used to provide a new secondary electrode to replace the partially consumed secondary electrode.

For the sake of completeness it should be noted that the mold 200 is cooled by water. This water flows to the installation through a flexible hose 390 (FIG. 4) and the cooling water will in this way reach the hollow interior 212 of the arm 211 of the mold carriage 210. The interior 212 of the arm 211 communicates with the hollow interior 205 of the upper lateral arm 204 of the mold 200. This hollow interior 205 of the arm 204 communicates with a hollow space 203 which is defined between an inner wall 201 and outer wall 202 of the mold 200, so that through the interior of the arm 204 the cooling water reaches the top end of the cylindrical space 203 to the flow down the latter. The cooling water flows downwardly along the hollow space 203 and then flows into the lower end of a conduit 206 the interior of which communicates fluidtightly with the hollow interior 203 at the bottom end of the latter. The cooling water will now flow upwardly along the conduit 206 in order to reach the hollow interior 208 of the other arm 207 of the mold 200, the interior of the conduit 206 communicating fluidtightly with the hollow interior 208 of the arm 207. This hollow interior 208 of the arm 207 communicates fluidtightly with the hollow interior 214 of the arm 213, so that the returning cooling water now flows through the interior of the arm 213, and a return holes 391 communicates fluidtightly with the interior of the arm 213, so that in this way the cooling water is circulated through the mold 200.

In the embodiment described above, the primary electrode carriage means 60 and 250 as well as as the secondary electrode carriage means and 290 are vertically movable along the

columns

70, 260, 30 and 220, respectively, by way of the cables and winches connected therewith, as described above.

In both of the above-described embodiments the molds 10 are 200 are of cylindrical configuration. The installation of the invention, however, can be used with molds of other configurations, such as, for example, molds which are of rectangular or square cross section.

As compared to known, conventional installations for electrically melting metals, the installation of the invention provides the advantage that it is extremely simple to carry out the exchange of one primary electrode for another as well as, if required, the exchange of one secondary electrode for another, even in those installations where the structure of the invention must be provided with relatively large dimensions. A further advantage of the installation of the invention resides in the fact that his always possible to adapt the structure to the space which is available. In the case where it is necessary to transport the primary electrode through a relatively large distance to the mold, so that there is a correspondingly large space available, the embodiment of FIGS. 1 and 2 is particularly suitable. On the other hand, the embodiment of FIGS. 3-5 is suitable for those situations where it is necessary to situate the installation of the invention over a particularly small area.

Although the invention is illustrated and described with reference to a plurality of preferred embodiments thereof, it is tovbe expressly understood that it is in no way limited to the disclosure of such a plurality of preferred embodiments, but is capable of numerous modifications within the scope of the appended claims.

What we claim is:

1. In an installations for electrically remelting steel or like metal to mold a given body from the remelted metal, comprising in combination,

at least vertically adjustable continuous casting mold means for molding the molten metal to the configuration of said body;

water cooling means operatively connected to said mold means for cooling the molten metal stored therein;

at least vertically adjustable primary electrode carriage means for maintaining a primary electrode of the metal to be remelted in operative relation with the mold means during the remelting the remelting of the primary electrode to provide molten metal in the mold means; at least vertically adjustable secondary electrode carriage means for supporting a secondary electrode to coact with the mold means for maintaining the molten metal in the mold means at its elevated temperature during the time when an at least partially consumed primary electrode is displaced from the mold means by means of the primary electrode carriage means and is exchanged for a new primary electrode; first transporting means operatively connected to said primary electrode carriage means for transporting said primary electrode carriage means to a location remote from the moldmeans for replacing the partly consumed primary electrode with a new primary electrode and for then returning the new primary electrode to the mold means for continuing the casting operations at the mold means with the primary electrode while the secondary electrode is displaced from the mold means by said secondary electrode carriage means; said secondary electrode carriage means and said mold means forming a pair of units to be displaced one with respect to the other to situate the secondary electrode at an operative location with respect to the mold means only during the time when the primary electrode is being changed and is displaced from the mold means; and second transporting means operatively connected with said one of said units for maintaining said secondary electrode carriage means and said mold means normally at locations where the secondary electrode does not participate in the operations and for maintaining the secondary electrode and mold means in an operative relationship with respect to each other only during the times when an at least partially consumed primary electrode is replaced with a new primary electrode. 2; The combination of claim 1 and wherein said first transporting means which coacts with the primary electrode carriage means to transport the primary electrode displaces the latter carriage means and a primary electrode therewith not only vertically, but also. horizontally. I

3. The combination of claim 1 and wherein at least one of said transporting means includes a crane carriage and tracks on which said crane carriage is horizontally movable.

4. The combination of claim 3 and wherein said crane carriage forms part of said first transporting means, a column carried by and extending downwardly from said crane carriage, and said primary electrode carriage means being vertically movable along said column as well as horizontally movable therewith in response to movement of the crane carriage.

5. The combination of claim 2 and wherein a pair of columns extend vertically and are parallel to each other, one of said columns supporting said secondary electrode carriage means for vertically movement, mold carriage means supporting said mold means and also supported by said one column for vertical movement, the other of said columns supporting said primary electrode carriage means for vertical movement, said second transporting means coacting with said secondary electrode carriage means for swinging the latter angularly about the axis of said one column, cable means coacting with said secondary electrode carriage means for displacing the latter vertically along said one column, said first transporting means coacting with said primary electrode carriage means for swinging the latter about the axis of said other column, and cable means also coacting with said primary electrode carriage means for displacing the latter vertically along said other column.

6. The combination of claim 4 and wherein a vertical column supports said secondary electrode carriage means for vertical movement, cable means coacting with said latter carriage means for displacing the latter vertically along said column, mold carriage means also supported by said column for vertical movement therealong and carrying said mold means, and cable means coacting with said mold carriage means for displacing the latter vertically along said column.

7. The combination of claim 6 and wherein said column has a noncircular cross section.

8. The combination of claim 5 and wherein said columns each have a noncircular cross section.

9. The combination of claim 8 and wherein a pair of support means respectively coact with the latter columns to support them for respective swinging movement about their axis.

10. The combination of claim 9 and wherein said first transporting means includes a drive operatively connected with said other column which supports said primary electrode carriage means for turning said other column about its axis, said one column carrying a sleeve which is vertically shiftable therealong and said secondary electrode carriage means being swingable about said sleeve, and said second transporting means including a drive operatively connected to the latter carriage means for turning the same about said sleeve and thus about the axis of said one column.

Claims

1. In an installations for electrically remelting steel or like metal to mold a given body from the remelted metal, comprising in combination, at least vertically adjustable continuous castinG mold means for molding the molten metal to the configuration of said body; water cooling means operatively connected to said mold means for cooling the molten metal stored therein; at least vertically adjustable primary electrode carriage means for maintaining a primary electrode of the metal to be remelted in operative relation with the mold means during the remelting the remelting of the primary electrode to provide molten metal in the mold means; at least vertically adjustable secondary electrode carriage means for supporting a secondary electrode to coact with the mold means for maintaining the molten metal in the mold means at its elevated temperature during the time when an at least partially consumed primary electrode is displaced from the mold means by means of the primary electrode carriage means and is exchanged for a new primary electrode; first transporting means operatively connected to said primary electrode carriage means for transporting said primary electrode carriage means to a location remote from the mold means for replacing the partly consumed primary electrode with a new primary electrode and for then returning the new primary electrode to the mold means for continuing the casting operations at the mold means with the primary electrode while the secondary electrode is displaced from the mold means by said secondary electrode carriage means; said secondary electrode carriage means and said mold means forming a pair of units to be displaced one with respect to the other to situate the secondary electrode at an operative location with respect to the mold means only during the time when the primary electrode is being changed and is displaced from the mold means; and second transporting means operatively connected with said one of said units for maintaining said secondary electrode carriage means and said mold means normally at locations where the secondary electrode does not participate in the operations and for maintaining the secondary electrode and mold means in an operative relationship with respect to each other only during the times when an at least partially consumed primary electrode is replaced with a new primary electrode.

2. The combination of claim 1 and wherein said first transporting means which coacts with the primary electrode carriage means to transport the primary electrode displaces the latter carriage means and a primary electrode therewith not only vertically, but also horizontally.