JPH04258345A - Method and device for continuous casting - Google Patents

Abstract

PURPOSE:To offer a high quality cast billet without any crack in the grain boundary of columnar crystal on the surface of the cast billet caused by intermittent drawing and blow holes and segregation caused by stripe-state raggedness, in a continuous casting method, in which a molten metal is cooled through a mold and a cooler attached to a melting furnace and the cast billet is continuously drawn through a pinch rolls. CONSTITUTION:The device provided with the melting furnace 3 attached with the mold 1 and the cooler 2, the pinch rolls 4, a carriage 8 for placing the melting furnace 3 and cam mechanism 7 reciprocally oscillating this carriage to the pinch roll direction and adding a driving motor 10, is used and reciprocating oscillation having 0.5-3mm amplitude and 0.2-10Hz number of the oscillations is imparted to the melting furnace. By this method, the above-mentioned flaw in the quality is eliminated and the continuous casting can be executed, and the improvement of quality, yield and productivity can be obtd.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous casting method and apparatus.

0002

2. Description of the Related Art A conventional continuous casting method will be explained using FIG.

[0003] In a continuous casting apparatus consisting of a melting furnace 3 and pinch rolls 4 equipped with a mold 1 and a cooler 2, when performing continuous casting, a dummy bar 5 is placed in the mold 1 in advance.
is inserted. When the dummy bar 5 is taken up by the pinch rolls 4, the molten metal 6 is dragged by the dummy bar 5 and flows into the mold 1. The molten metal 6 that has flowed into the mold 1 is cooled by the cooler 2 of the mold 1 and solidified. The solidified ingot is connected to a dummy bar 5 and taken off by pinch rolls 4.

When taking the ingot, a stable solidified shell is formed in the mold and then taken out to prevent cracks on the surface of the ingot due to friction between the ingot and the mold. Intermittent continuous operation was carried out, waiting for the formation to take place.

[0005]

When continuous casting is carried out in the prior art, as described above, the ingot is taken intermittently by pinch rolls, which alternately take up and stop the ingot.

However, in this method, when the ingot is released from the mold, there is a risk that cracks may occur at grain boundaries of columnar crystals on the surface of the ingot.

[0007] In addition, ingots cast using conventional techniques have striped irregularities or striped casting patterns on the surface due to intermittent withdrawal, and the striped areas tend to have cavities and segregation, resulting in poor quality. This was the problem above.

An object of the present invention is to provide a novel continuous casting method and apparatus that can eliminate the drawbacks of the prior art described above and can cast high-quality ingots free of cracks and segregation. be.

[0009]

[Means for Solving the Problems] The above-mentioned object of the present invention is to provide a continuous casting method in which molten metal is cooled while passing through a mold and a cooler attached to a melting furnace, and the ingot is continuously taken up by pinch rolls. A continuous casting method, characterized in that the melting furnace is reciprocated in the direction of the pinch rolls while the ingot is taken up by the pinch rolls. Alternatively, in a continuous casting device consisting of a melting furnace equipped with a mold and a cooler, and pinch rolls that take up the ingot drawn out with a dummy bar, a cart on which the melting furnace is mounted, and a cart that reciprocates in the direction of the pinch rolls. This is achieved by a continuous casting device characterized by having a cam mechanism that vibrates and its power.

The reciprocating vibration in the direction of the pinch roll in the present invention is carried out by, as a specific example, a cam mechanism and its power for reciprocating vibration in the direction of the pinch roll and a cart on which the melting furnace is mounted. However, as for the cam mechanism, it is preferable that the lever as a driven joint is moved by the rotational movement of a planar cam, although a plate cam or groove cam may be used, a circular end is used as a contact, and a cam curve having a cycloidal curve is used. The amplitude of the reciprocating vibration of the melting furnace is 0.5
~3 mm and a vibration frequency of 0.2 to 10 Hz are preferable.

[0011]

[Operation] In the conventional technology, when taking an ingot, a stable solidified shell is formed inside the mold to prevent cracks from occurring on the surface of the ingot due to friction between the ingot and the mold. Intermittent withdrawal was performed by waiting for the formation of a solidified shell to be withdrawn, but the vibration of the melting furnace and mold due to the cycloid cam curve of the present invention reduces the friction between the mold and the ingot, making it easier to remove the ingot. It is now possible to pick up items continuously.

[0012] This prevents cracks from occurring at the grain boundaries of the columnar crystals on the surface of the ingot when the ingot separates from the mold. In addition, the striped irregularities or striped casting patterns that had formed on the surface of the ingot due to intermittent withdrawal disappeared, and the cavities and segregation that occurred in the striped areas also disappeared.

[0013]

[Embodiment] An embodiment of the present invention will be explained with reference to FIG.

The continuous casting apparatus of the present invention includes a melting furnace 3 to which a mold 1 and a cooler 2 are attached, a pinch roll 4, a cart 8 on which a new melting furnace 3 is placed, and a cart 8 that reciprocates in the direction of the pinch rolls. A cam mechanism 7 and a cam drive motor 10 were added.

In this apparatus, when performing continuous casting, a dummy bar 5 is inserted into the mold in advance. Further, the melting furnace 3 to which the mold 1 and the cooler 2 are attached is fixed on a truck 8, and the truck 8 is moved along the rail 9 in the mold take-off direction by a cam mechanism 7 and a cam drive motor 10. It vibrates back and forth. The amplitude at this time is 0.5 to 3 mm, and the vibration frequency is 0.2 to 10 Hz.

The dummy bar 5 is continuously taken off by the pinch rolls 4. The molten metal 6 is dragged by the dummy bar 5, flows into the mold, passes through the mold 1, is cooled by the cooler 2, and solidifies. The solidified ingot is continuously taken off by pinch rolls 4.

[0017]

[Effect of the invention] The continuous casting method and apparatus of the present invention provide
Cracks at the grain boundaries of columnar crystals on the surface of the ingot due to friction between the ingot and the mold no longer occur, and striped casting patterns are also eliminated.
Therefore, the cavities and deflections that occurred in the striped pattern areas were eliminated, contributing to an increase in quality and yield. Also, it became possible to perform casting truly continuously rather than intermittently, contributing to an increase in productivity.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of the continuous casting method and apparatus of the present invention.

FIG. 2 is a cross-sectional view showing an example of a conventional continuous casting method and apparatus.

[Explanation of symbols]

1 Mold 2 Cooler 3 Melting furnace 4 Pinch roll 5 Dummy bar 6 Molten metal 7 Cam mechanism 8 Trolley 9 Rail 10 Cam drive motor

Claims (2)

[Claims] 1. A continuous casting method in which molten metal is cooled while passing through a mold and a cooler attached to a melting furnace, and the ingot is continuously taken up by pinch rolls, wherein the melting furnace is moved in the direction of the pinch rolls. A continuous casting method characterized in that the ingot is taken up by the pinch rolls while reciprocating vibration. 2. A continuous casting device comprising a melting furnace equipped with a mold and a cooler, and pinch rolls that take up the ingot drawn out with a dummy bar, in which a cart on which the melting furnace is mounted and a reciprocating vibration in the direction of the pinch rolls. A continuous casting device characterized by having a cam mechanism and its power.