DE2362720A1 - ELECTROMAGNETIC STIRRING DEVICE FOR A CONTINUOUS CASTING PLANT - Google Patents

Description

9245-73 / Dr.vB / Ba
FR-PA No. 72.45725
AT December 21, 1972

COMPAGNIE ELECTRO-MECANIQUE 12, rue Portalis, Paris 8e (France)

Electromagnetic stirring device for a continuous casting plant

In continuous metal casting, the ingot consists of what it is made of The shaping mold emerges continuously and very slowly, from an outer crust that has already solidified when it left the mold and an inner part that is still liquid, the Melting core, the cross-section of which is progressively reduced in a so-called secondary cooling zone as the ingot continues to sink.

It is known - that by moving the liquid metal during the solidification process and the resulting mixing or stirring improves the structure and homogeneity of the solid metal will. It is known to use a rotating magnetic field for this purpose, which the liquid column around the longitudinal axis of the ingot rotates at a moderate speed.

This magnetic field can be wound with the help of an annular Magnet arrangement are generated in the manner of the stator of an AC or three-phase motor, the empty interior through the the ingot moves in the course of solidification, is penetrated by a rotating magnetic field in the transverse direction.

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One such ring-shaped magnet arrangement is intense radiation exposed to the ingot passing through, partially solidified and still very hot, the danger of rapid destruction can therefore only be avoided by using effective cooling measures.

According to the present invention, effective cooling is achieved by completely immersing the magnet arrangement (inductor) in strong flowing water, which is in a container, guaranteed. To achieve this, the annular magnet assembly in a sealed, annular container which has an inlet and an outlet opening for the cooling water, so mounted, that the water flows first from top to bottom in an annular channel that extends from the outer wall of the container and the periphery a stack or package of annular thin sheet metal plates is formed, which on its inner edge grooves for has the conductors or cables of the coil. The water then flows horizontally again around the ladder of the lower winding heads, then from the bottom up through the grooves and a narrow annular passage between the inner edge of the sheet and the inner wall of the container and finally horizontally above the laminated core around the conductors of the upper end windings, to finally drain through the outlet opening.

To prevent the coil conductors from being damaged by the cooling water, they consist of flexible wires with a twisted one Inner conductor surrounded by waterproof insulation. For example, you can use a flexible wire with a circular cross-section and a diameter of 6 mm with a copper core of 3 mm. Although such wires do not fill the grooves well, however, they are sufficient to obtain a magnetic field of the desired strength and allow the cooling water to pass well through the between its cylindrical walls free spaces can circulate, even if they touch.

Another difficulty is the watertight out-

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leading the ladder. To this end, they exist according to a Further development of the invention there from solid conductors that traverse an insulating plate provided for this purpose in the container wall and connected inside the container to the carefully insulated ends of the cable-like coil conductors.

To ensure the sealing and the desired insulation of the connections between the coil ends and the solid conductors, the stripped coil conductor ends are soldered into holes in the solid conductors; the ends of the cable-like coil conductors and the massive conductor are surrounded by sheaths made of thermosetting material and the whole is encapsulated with cast resin, in an insulating sleeve, which is in a designated Groove is made in the lower surface of the insulating plate; the massive conductors have a collar on the inside, which is under the intermediate layer a sealing ring is pressed against the inside of the insulating plate by means of a clamping screw.

Finally, the container is designed to be used for its interior cleaning and access to the conductors and connections is easy to dismantle.

The drawings show exemplary embodiments of the invention, namely:

Fig. 1 is a vertical section through an electromagnetic stirring device for metal continuous casting;

FIG. 2 shows a cross section in a plane II-II of FIG. 1;

Fig. 3 is a cross-sectional view of the electromagnetic used Contraption;

FIG. 4 shows a cross section in a plane IV-IV of FIG. 3;

5 shows an enlarged section through an embodiment for a coil conductor.

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1 shows a continuously cast ingot which emerges from a casting mold, not shown, which is open at the bottom and has an already solidified part 1 and a fusible core 2 made of still liquid metal inside. The bar travels through a cylindrical hollow middle part of a container 3, generally the inside of which is a winding with a lower and upper winding head 6 _and 7 in grooves 5 of a magnetic sheet stack 4 "

Cooling water is introduced into the container 3 through an inlet opening , it then flows from top to bottom between the outside of the magnetic laminated core 4 and the outer wall 9 of the container 3, then horizontally in the lower part of the container around the lower winding heads to cool? and then from bottom to top through the grooves 5 of the Magnetfoiechpakets nnä riter through a free space 10 between the ring-shaped inner side of the Magnet ™ sheet metal sheet 4 and the inner wall 11 of the container 3 "nm finally horizontally in the upper part of the cable-like container Head of the upper winding heads 7 evl cool and one -Auslaßö f fnung 12 au s ζ utreten ο

From the figure that goes into detail®. 3 it can be seen that a clamping plate 13 of the sheet metal package 4 has radial channels 14 through which the cooling water flows inwards and thus reaches the winding heads S through openings 15 provided for this purpose Treanen rad flows daaa äurcii the Hutsai 5 containing the coil conductors, among other things, the space 10 between the inner surface of the magnetic laminated core 4 and the inner wall 11 of the container to ob & Ug and further through radial spaces 19 between plates _B which the upper winding heads? separate, in order to cool the latter, before it flows out through the outlet opening 12 _. ensure that no Lufttasdhies ± sa © ready, annular space between the sweet wall 9 of the container and the magnetic sheet package 4 can form «,

-AO 98 26 / 0-8 2 2

The container 3 consists of a lower and an upper part / which forms an easily removable cover and with screw rings 20 and 21 is attached; the seal is ensured by the seals 22 and 23. After loosening the screws of the screw rings 20 and 21 and lifting off the upper part of the container you have free access to the windings and the connections and the container can be cleaned easily.

To ensure good electrical insulation with sufficient sealing against the cooling water to ensure _r may be formed for the coil conductors as the feedthroughs, as illustrated in Fig. 5: They contain solid conductors 24, an insulator plate 25, which forms part of the container wall , enforce in a connection housing 26. For this purpose, as shown in FIG. 5 on an enlarged scale, stripped ends 17 of flexible coil wires 28 are each soldered into a bore 29 of solid conductor parts 30 and the connection is sealed with the aid of a sleeve 31 shrunk on by the action of heat; The whole is cast with Hsr2 32 in an insulating sleeve 33, the outer edge 34 of which is pressed into a groove in the insulating plate 25 provided for this purpose. The bushing is fastened to the insulator plate 25 by its clamping screw 35, while the ring seal 36 is compressed and the seal is thus ensured. A cable lug 37 can then be attached by means of a screw nut 38.

Of course, the embodiment of the invention described above with reference to the drawings can be in the most varied of ways Modify manner without departing from the scope of the present invention.

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Claims (8)

236272Q patent claims 1) Electromagnetic stirring device for a continuous casting plant, in which a metal bar containing a still liquid core emerges slowly and continuously from a casting mold, characterized in that an inductor (4) for generating a rotating magnetic field in the manner of a stator of an asynchronous electric motor coaxial to the exiting from the mold and solidifying ingots (1, 2) is arranged that the inductor is arranged in a water-filled container (3) and completely surrounded by the water in the container and that an arrangement sum generating a strong circulation of the Cooling water inductor is provided » 2) Stirring device according to claim 1, characterized in that the inductor in a tight ^ ring-shaped container (3) with an inlet uad an outlet opening (8 bsw. 12} for the cooling water is arranged such that the water first from top to bottom flows through an annular channel which is located between the outer wall (9) of the container (3) and the outside of an annular package of thin magnetic foils with grooves C5) for the coil conductors, then horizontally around the conductors from lower winding heads " then further from below up through the hats and a narrow ring-shaped channel between the inside of the laminated core (4) "ad the inner container _{wall 0} and finally horizontally above the laminated core uTti the ladder of the upper winding heads until it finally emerges through the outlet opening (12)"" 3) Stirring device according to claim 1 or 2 ₀ characterized in that the coil conductors. Consist of a flexible wire with a twisted, strand-like InnafLeifeer and a watertight insulation surrounding it » 40 236272Q 4) stirring device according to claim 3, characterized in that that a flexible wire with a circular cross-section of 6 mm diameter and a 3 mm thick copper core is used will. 5) Stirring device according to one of the preceding claims, characterized in that the conductor bushings have a massive Conductor (24) included, which crosses a provided for this purpose in the wall of the container insulator plate (34) and in the Inside the container with the carefully insulated coil conductor ends (27) is connected. 6) stirring device according to claim 5, characterized in that the insulated conductor ends (27) in bores (27) of the massive Conductors are soldered in that the conductor ends (27) and the ends (30) of the corresponding solid conductor with sleeves (31) are surrounded by thermosetting or heat-shrinking material, and that the whole is inside an insulating sleeve (33) filled with resin (32), the outer wall of which is inserted into a sleeve provided for this purpose Hat is recessed on the lower side of the insulating plate, is arranged. 7) stirring device according to "claim 5 and 6, characterized in that that the solid conductors on the inside on a collar, which with the interposition of a sealing ring (36) with With the help of a clamping screw (35) is pressed against the inside of the insulator plate (34). 8) Stirring device according to one of the preceding claims, characterized in that the container (3) consists of a lower and an upper part which forms an easily removable cover fastened by means of screw rings (20, 21) and is sealed by seals (22,23). 409826/0822 Le e rs e i ie