RU2604278C2 - Installation for electric heating of ladle lining - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy. Plant includes a mechanism for moving a ladle, rod resistance heaters, fixed on heat-insulated cover, suspended by means of flexible links on a cross beam, lever lifts for movement of cross beam, mounted on a working site. Laser sensor is installed on cross beam, which laser sensor controls vertical position of heaters during movement of cross beam. On working site there is a laser sensor for detection of crust on upper end surface of ladle. Processes of heating and movement of heaters and ladle are performed by an automatic control system.

EFFECT: eliminating impact loads, leading to breakage of heaters, and longer service life of group of heaters.

1 cl, 4 dwg

Description

The invention relates to electric resistance furnaces used in metallurgy, in particular to electric heating furnaces with rod heating elements used for electric heating and drying of the lining of metallurgical and foundry ladles.

Similar designs of electric drying and heating systems for the lining of metallurgical and foundry ladles are developed and supplied to consumers by CS Elektro as Norway (Electric Drying and Preheating for refractory Linings catalog).

As the closest analogue of the invention, an installation for electric heating and drying of the lining of metallurgical and foundry ladles is adopted, comprising a heat-insulating lid with resistance heaters fixed to it and an electric power supply (SU 1662756 A1, July 15, 1991).

As the experience of operating electric furnaces designed for heating and drying the lining of ladles shows, their huge advantage compared to flame heating furnaces is their high thermal efficiency (up to 90%) and the absence of harmful emissions into the surrounding space.

However, the main disadvantage of the above designs of electric heating plants is the low resistance of heaters with increased fragility and failure at elevated speeds and frequent breakdowns due to contact with the influx of slag and metal due to overgrowth of the cross section of the bucket during its operation.

Based on the foregoing, the main task, the solution of which the claimed invention is directed, is to increase the service life of the heaters.

The technical result of the application of the claimed invention is to increase the axial symmetry of the group of movable heaters, as well as the elimination of shock loads leading to their breakdowns.

A positive result of the use of the claimed invention is also the efficiency and convenience of monitoring the operating condition of the heaters.

The above technical results during the implementation of the invention are achieved by the fact that, in contrast to the known designs of heating furnaces, the energy radiated by the heaters is almost completely absorbed by the walls of the bucket.

In FIG. 1, 2, 3 presents a general view of the installation. The installation consists of resistance heaters (1), mounted on a heat-insulating cover (3), which is suspended by means of flexible rods (2) on a traverse (5). On both edges of the traverse (5) are lever lifts (6) and shock absorbers (8), which are installed on the working platform (9). It also has a heat shield (10), covering the cover (3) with heaters (1); along the edges of the screen are vertical grooves for moving the traverse (5). Under the working platform (9) there is a rail track (11) along which a trolley (12) moves, on the upper side of which there are catchers (13), inside which a steel pouring ladle (4) is installed.

The installation is equipped with a laser sensor of the accretion detection system (14), mounted on the work platform (9) along the path of the bucket (4) and a tilt angle sensor (7), mounted on the traverse (5). The installation has a power thyristor cabinet (15) and a control and management cabinet (16).

Installation works as follows.

Using the workshop crane, the steel pouring ladle (4) is mounted on the trolley (12) located at the “loading” position, with the help of catchers (13) the bucket (4) is centered on the trolley (12) in a strictly defined position. After that, the trolley (12) with a bucket (4) is supplied with an electromechanical drive under the work platform (9) to the heating position. According to a signal from the control and control cabinet (16), the lever lifts (6) begin to fold and the beam (5) with the cover (3) suspended on it using flexible rods (2) with heaters (1) is lowered down until the cover (3) will not lie on the top of the bucket (4). The presence of flexible rods (2) ensures reliable contact of the lid (3) with the upper end of the steel pouring ladle (4) even with minor irregularities of the latter. After that, power is supplied from the thyristor cabinet (15) to the heaters (1) and the lining of the steel pouring ladle (4) is heated. After heating, the traverse (5) with a cover (3) and heaters (1), lever lifts (6) are moved to the highest position, where they are until the next cycle, protected by a heat shield (10) from sudden cooling. After raising the heaters (1), the trolley (12) with the bucket (4) is moved to the unloading position, where the heated bucket (4) is removed and a new one is installed, after which the cycle is repeated.

In order to exclude mechanical damage to the heaters from the influx of slag and metal at the upper end of the bucket, the installation is equipped with a laser sensor (14) mounted on the work platform (9) along the path of the bucket. In the case when the influx exceeds the permissible value, the laser sensor (14) is activated and, upon a signal from the control and control cabinet (16), the trolley returns to its original position for cleaning the bucket (4).

In the case when the influx is less than the permissible size, the carriage (12) with the bucket (4) stops at the heating position. The yoke (5) with the lid (3) and heaters (1) is lowered to the lower position, the lid (3) rests against the influx at the end of the bucket (4), the load on the yoke (5) is reduced, and it is stopped by the shock absorber (8), so as the working load of shock absorbers (8) does not exceed the total weight of the traverse (5) with the cover (3) fixed to it with heaters (1). At this time, the opposite side of the traverse (5) is still under load from the cover (3) fixed on it with flexible rods (2) and continues to fall down. As a result, the sensor (7) of the angle of inclination, which monitors the vertical position when moving.

Folding lever lifts (6) stops, and therefore, stops lowering the lid (3), and the heaters (1) do not break as a result of the absence of a blow to the lining of steel pouring ladles (4).

Claims (1)

Installation for electric heating and drying of the lining of metallurgical and foundry ladles, comprising a heat-insulating lid with resistance heaters fixed on it and an electric power source, characterized in that it is equipped with a bucket moving mechanism, a traverse, lever lifts for moving the traverse installed on the working platform, a laser sensor the angle of the heaters mounted on the traverse, controlling the vertical position of the heaters when moving the traverse, the detection system accretions on the upper end surface of the ladle, comprising a laser sensor, mounted on the work platform, and the automatic process control system of the heating and moving the heaters and the bucket, wherein the insulating cap is fixed on the crosspiece by means of flexible rods.

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