JPS6146357A - Molten steel heater for continuous casting installation - Google Patents

Abstract

PURPOSE:To provide a molten steel heater having high resistance to erosion by disposing gates provided with conductive ceramic electrodes to a tundish and forming an electricity conducting circuit between the conductive ceramic electrodes immersed into a casting mold. CONSTITUTION:The conductive ceramic electrodes 20 are attached to the gates 14 provided in order to remove the inclusions of the molten steel in the tundish 10 and the electricity conducting circuit 15 is formed between the conductive ceramic electrode 17 immersed in the mold 12. The molten steel heater which has the high resistance to erosion and for which the gates and the electrodes for heating the molten steel are commonly used concerning heating of the molten steel of a continuous casting installation is thus obtd. and the effective prevention of the clogging of a pouring nozzle is made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a molten steel heating device for continuous casting equipment.

(Prior Art) When pouring molten fJ4 into a mold from a ladle or tundish, the molten steel often solidifies and adheres to the inner wall of the pouring nozzle, reducing the pouring speed and making pouring impossible. In particular, such nozzle blockage has been experienced in tundish pouring nozzles used in continuous casting methods where the pouring temperature is low.

This is because the melting point of the pouring nozzle is much lower than the melting point of the molten metal, so during pouring, the molten metal that comes into contact with it is cooled and solidifies on the inner wall of the nozzle, and furthermore, during the pouring process, the solidification core gradually forms. This is because the particles grow, narrowing the nozzle cross-sectional area, and eventually clogging the nozzle.

Therefore, in order to prevent such accidents from occurring, a method is generally known in which the pouring nozzle is preheated.

However, there is a disadvantage that the temperature of the nozzle that can be preheated by such a method cannot be expected to be high. Also, Unexamined Patent Publication 1973-
In Japanese Patent No. 130364, when pouring molten steel from a tundish into a mold, a high-frequency current is fully applied to the molten steel passing through the injection nozzle, so that the surface of the molten steel in the nozzle and the inner surface of the nozzle are completely heated due to the skin effect of the high-frequency current. Therefore, methods for preventing clogging of molten metal nozzles have been proposed. In that case, as the electrode material for supplying current to the molten steel, a material such as 1-Pon was considered, but it was not put to practical use because of the large amount of melting loss in the molten steel.

(Problems to be Solved by the Invention) The present invention provides a molten steel heating device using an electrode that has high erosion resistance against molten steel and has very low electrical resistance.

(Means and effects for solving all the problems) The present invention is a system for heating molten steel by electricity in a tundish and a mold of continuous casting equipment. This is a molten steel heating device for continuous casting equipment, characterized in that a current-carrying circuit is formed between conductive ceramic electrodes.

The invention will be explained below with reference to the drawings.

Fig. 1 is a detailed explanatory diagram of the present invention, Fig. 2 is a partial explanatory diagram of the present invention, and Fig. 3 (al, (b)) is an explanatory diagram of a weir of the present invention.

In the figure, 10 is a tundish, 11 is a ladle, 12 is a mold, 13 is a stopper, 14 is a weir, 15 is an energizing circuit,
16 is a pouring nozzle, and 17 is a heating electrode. The continuous casting equipment of the present invention is a system in which all of the molten steel in the tundish 10 and mold 12 is energized and heated.Recently, with the development of continuous casting technology, the number of devices installed in the tundish has greatly increased. For example, there are a nozzle stopper weir, a temperature sampling device, a pot nozzle, etc.

The part of the upper part of the tundish that the pot covers is
It is difficult to install these devices due to lack of space.

By the way, as a means of removing inclusions of molten steel in the tundish, a weir 1 is installed in the tundish 10 as shown in FIG.
It is known that there are four. The present invention eliminates the need to newly install an electrode for current heating by placing a gold film on the electrode for current heating on a weir installed to remove inclusions from molten steel, making the installation more compact. .

The weir 14 in the present invention, as shown in FIG. 3(a),
Contains 21 conductive ceramics and water-cooled copper bronze.
The terminal η is electrically connected to the current-carrying circuit 15 through the gate 21. Weir 1
4 is a boride ceramic such as ZrB2, TiO2
and this composite sound conductive ceramic. As another example, a conductive ceramic electrode 20 is disposed to constitute a part of the weir 14, and a power supply block 23f is provided at the end of the electrode (9) to be electrically connected to the current supply circuit 15.

In order to carry out its true nature, a separate device to hold the electrode in molten steel is required (this made it very simple. Also, for example, Z'rB2 has a lower electrical resistance than a conventional carbon electrode). , 15500-1570t, with low self-heating amount and without abnormally increasing the temperature of the weir body;
It was possible to use the molten steel of 20,000 OOA and 5V of electricity satisfactorily using this equipment.

(Effects of the Invention) The present invention provides a system in which molten steel is electrically heated in a tundish or mold of continuous casting equipment, by providing a conductive ceramic electrode in a weir used by immersion in molten steel, so that the weir and the molten steel heating electrode can be used together. As a result, the temperature of the molten steel can be increased and the clogging of the pouring nozzle can be prevented, which has great industrial effects.

[Brief explanation of the drawing]

FIG. 1 is an overall explanatory diagram of the present invention, FIG. 2 is a partial explanatory diagram of FIG. 1, and FIG. 3 is a detailed explanatory diagram of the present invention.

Claims (1)

[Claims] 1. In a system for electrically heating molten steel in a tundish and a mold of continuous casting equipment, a weir provided with conductive ceramic electrodes is disposed in the tundish, and between the conductive ceramic electrodes immersed in the mold, A molten steel heating device for continuous casting equipment, characterized by forming a current-carrying circuit. 2. A molten steel heating device for continuous casting equipment according to claim 1, wherein a weir made of conductive ceramics is arranged in a tundish.