JPS61108456A - Powder melting device for continuous casting - Google Patents

Abstract

PURPOSE:To prevent the generation of breakout and the surface defect of a slab by melting preliminarily the powder to be supplied to the mold of a continuous casting machine and adjusting the supply rate thereof from the change in the quantity of the electricity to be conducted. CONSTITUTION:The powder supplied from a hopper 5 to a melting vessel 7 is melted by the electrical heating effect of an electrode 6 and only the powder in the molten state is supplied from the lower part of a gate 8 to the mold 9. Since the powder is melted by arc heat or the heat-generating effect of the powder itself by the conduction of electricity, there is no need for installing freshly a heating source and the compact device is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a powder melting device for a continuous casting device for molten steel.

[Conventional technology]

During continuous casting of molten steel, powder is supplied to the mold in order to prevent the shell formed by the solidification of the molten steel from adhering to the mold. Powder is usually introduced in powder form, melted by the heat of molten steel in the mold, and flows in liquid form between the mold and the solidified shell to achieve the desired purpose. However, since the amount of powder supplied into the mold is not uniform and the amount of powder consumed at each position of the mold is not constant, excess or deficiency of powder occurs locally within the mold. For this reason, defects may occur on the slab surface due to adhesion due to insufficient powder.

There has been a problem in that unmelted powder flows into the gap between the mold and the solidified shell, causing the solidified shell to rupture and the molten steel inside to flow out.

For this reason, in conventional devices, as shown in Japanese Patent Application Laid-Open No. 58-32559, a sub-control device is installed in close proximity to the mold of the powder supply device to enable command and monitoring of the supply amount and to supply an appropriate amount of powder to the mold. In addition, as shown in Japanese Patent Laid-Open No. 58-148062, there are examples in which a heat flux meter is provided in the mold to detect areas where there is little powder inflow and control the amount and location of supply.

[Problem to be solved by the invention]

However, none of these methods can completely solve the problem of undissolved powder flowing between the mold and shell and causing breakouts.Therefore, there has been a proposal to melt the powder in advance and then introduce it, Therefore, the heat source device was large, and it was difficult to install it in the space around the mold, making it impractical. The present invention proposes an apparatus for pre-melting feed powder to such continuous caster molds.

[Means to solve the problem]

The present invention is for melting powder in continuous casting, characterized by comprising a powder melting container provided close to a continuous casting mold, and a conductive ceramic electrode disposed to melt the powder in the container. It is a device.

[Effect] This invention will be explained below with reference to the drawings.

FIG. 1 is a schematic diagram of the present invention, and FIG. 2 is a schematic diagram of the present invention installed in a continuous casting machine.

In Fig. 1(a), a conductive ceramic electrode 2 is inserted into powder 1, power is supplied from a power source 4, and the powder is melted by the arc generated between the electrodes and the heat generated by the energizing action of the powder itself. . As for the method of installing the electrodes, in addition to the method shown in FIG. 1(a), it is also possible to use the powder dissolving container 3 as one electrode as shown in FIG. 1(b). In this case, the lining of the melting vessel 3 is lined with conductive ceramics, which is used as an electrode to conduct electricity.

The ceramic used for the electrode 2 or 3 is preferably one that has conductivity and excellent corrosion resistance against powder in a high-temperature molten state.
Ceramics containing rB, TiB, and composites thereof as main components are suitable.

FIG. 2 shows an example of the application of the present invention, in which from the hopper 5,
The powder placed in the melting container 7 is melted by the heating action of the electrode 6, and only the molten powder is supplied to the mold 9 from the lower part of the weir 8.

As described above, in the present invention, the powder is melted by arc heat or by the heat generation effect of the powder itself due to energization, so there is no need to newly install a heating source. Therefore, the device is extremely compact and can be stored in a narrow space on the upper side of the mold of a continuous casting machine.

In addition, the amount of powder charged to the mold can be easily adjusted with high accuracy by changing the amount of one energization.

〔Example〕

The powder melting device of the present invention was installed on the upper side of the continuous caster mold, the powder was pre-melted, and the device was used for 6 months. The ingredients of the powder used are 5i0245%, AQ□
0144%, C7%.

CaO2%, Fe2O, 2%, 1000V between electrodes,
It was possible to melt and supply by applying a current of 2A.

ZrB2 was used as an electrode, and it withstood use for 6 months and was good, but other carbon electrodes and metal electrodes were not preferable because they melted and the components of the powder changed.

With the use of this device, breakouts caused by conventional undissolved powder inflow and overfeed or underfeed did not occur during the six-month period of use.

〔Effect of the invention〕

This invention prevents the occurrence of breakouts and slab surface defects by melting the powder supplied to the mold of a continuous casting machine in advance and precisely adjusting the supply amount by changing the amount of energization. The effect is significant.

[Brief explanation of drawings]

FIG. 1(a) is an explanatory diagram of the powder melting device of the present invention;
FIG. 1(b) is a detailed explanatory diagram of the present invention, and FIG. 2 is a detailed explanatory diagram of the present invention. 1: Powder 2: Conductive ceramics electrode 3: Powder melting container 4: Power source 5: Hopper 6: Conductive ceramics electrode 7: Powder melting container 8: Weir 9: Mold

Claims (1)

[Claims] 1. A continuous casting powder melting device comprising: a powder melting container disposed close to a continuous casting mold; and a conductive ceramic electrode disposed in the container for melting powder.