SU48407A1 - Device for mixing and partial heating of a metal in an open-hearth furnace - Google Patents

Description

The beneficial effect of mixing the bath of a steel-smelting furnace on the course of metallurgical processes has led to numerous attempts at mixing metal and slag.

Stirring capable of actually improving melting conditions should result in:

1. Acceleration of diffusion of reacting elements and leveling their concentration in different zones of the bath.

2. Acceleration of dissolution of solid particles in a liquid bath due to impaired local saturation of the solution.

3. Replacing contiguous layers of slag and metal.

4. Aligning bath temperature.

5. Facilitating removal of non-metallic inclusions from the bath.

In order to obtain a sufficient effect, the mixing must be long, systematic, intense, automatic, and applied in any period required during smelting.

Until now, the mixing of the metal bath was carried out only in electric steel-smelting furnaces.

The present invention aims at mixing the conducting bath in furnaces of the Martin type.

This is achieved electrodynamically by means of a special multiphase winding of several coils due to the interaction of a magnetic field moving in space and currents induced in the bath. For the purpose of mixing and partial heating of the bath of an open-hearth furnace, a device is used consisting of a winding that creates a rotating magnetic field when the coils are turned on in a network in various ways.

In FIG. 1 shows a perspective section of an open-hearth furnace; FIG. 2 exemplary winding switching network.

The two windings A and are connected to the appropriate supply network, either directly or through a transformer.

The coils of each of the windings are located on one side of the bath, for example, from below, so that the coil Lz overlaps two rows of coils L1 and Ld and together with them forms a system that creates a bath mixing around the horizontal longitudinal axis of the bath, and the coil L, aside to the end slopes of the furnace, it forms with the coils L1 and A a system that creates mixing around the vertical axis.

Winding B, consisting of coils BI, B, BZ and b, is similar to winding A in everything and is intended to enhance the action of the device mixing

a bath. The windings A and B may not consist of four coils each, as shown in the drawing, but of a different number, for example six or more, and the bath may be covered by the coils in a greater or lesser degree than shown in FIG. one.

Winding A and JB can be placed in the refractory masonry of the furnace or outside the lining. The number of coils, the number of phases, the frequency of the supply current and the placement of the coils may vary, however, the arrangement of the coils, the shift of one coil relative to another, their number and switching circuit must ensure the formation of a space-rotating rotating circular or elliptical magnetic field.

The performance of the coils and their power can be designed to more or less participate in the heating of the bath.

Since the mixing of the metal around the longitudinal axis of the bath may be particularly desirable during certain periods of melting (for example, with a bale in an open-hearth furnace), and mixing around the vertical axis can be used during other periods of melting (for example, during melting and before release), this The invention provides for the use of both a single winding part, for example A, A, A, and a connected winding A-, A, A, A, B, B, B, Bt, which by connecting to the network different parts of the winding to obtain the desired direction of movement magnetically first floor and, therefore, mixing of the melt around the horizontal, around the vertical or inclined axis of the bath.

An exemplary coil connection circuit is shown in FIG. 2. The coils are grouped using KI, K, Kg switches, but can be performed by a switch or a controller.

Switching on coils A, A, Au and B-, B, B using the switch X creates a magnetic field causing mixing around the longitudinal axis of the bath. The coil groups A and B may have agreed

inclusion or may be included towards each other. In order to obtain a more vigorous mixing of the bath by creating vortices, the field rotation is reversed by switching coils to other phases using a K3 switch.

When the coils AB, A, A and B, B, Bz are turned on with the help of the switch Lz, a magnetic field rotating in the horizontal plane creates a stirring of the bath around the vertical axis. In order to improve the mixing, a change in the direction of rotation of the field was applied by switching coils with switch K. In the case of simultaneous switching on of all eight coils, switches, Ja, Hz, are turned on. and the mixing of the bath will occur as a result of two movements around the horizontal longitudinal axis of the bath and around the vertical axis of the bath. In magnitude and in direction, the resultant force will be different for different zones of the bath and mixing in these zones will occur around differently oriented axes.

Similar devices can be used for various flame smelting, steel smelting and other furnaces.

The subject matter of the invention.

A device for mixing and partial heating of a metal in an open-hearth furnace, characterized in that a multi-phase winding is used to create a rotating magnetic field interacting with the melt, consisting of several coils arranged in groups in such a way that magnetic fields are created for mixing the metal around the horizontal longitudinal axis of the bath alone or the vertical axis alone, or axes differently oriented for different zones of the bath. to the author's testimony of L, I. Morozensky and A. D. Khodyko L 48407

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