JPH01215439A - Electromagnetic field casting method - Google Patents

Abstract

PURPOSE:To prevent danger of explosion caused by contacting of leaked molten metal with cooling water by arranging heat insulating material in an electromagnetic shield ring and pressed-welding the heat insulating material to an ingot with compressed air at the time of power failure. CONSTITUTION:When the power failure happens during casting operation, electromagnetic force of an electromagnetic inductor 11 is eliminated, and there is fear of the molten metal 13 leaking out. However, at the same time of the power failure, a valve leading to compressed air storing is opened and the compressed air injected from compressed air supply tube 6 through air flow-out hole 9 bored to the electromagnetic shield ring 5. Then, the molten metal is solidified at lower end part 41 of the heat insulating material arranged at inner face of the ring 5, to push to the ingot surface formed. By this method, a large part of the molten metal can be prevented from leaking out and also the molten metal leaking from gap of the heat insulating material is scattered with the compressed air to make particle state and blown out in the cooling water for the ingot, cooled and solidified.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electromagnetic field casting method that prevents dangers during power outages.

[Prior Art] As shown in Japanese Patent Publication No. 50-27807, electromagnetic field casting is carried out using a mold consisting of an annular electromagnetic inductor for generating a magnetic field, an electromagnetic shield, and a cooling water supply device.

As shown in FIG. 4, this mold has an annular electromagnetic inductor 11 surrounding the molten IjJ 13 and the ingot 14 in which it has solidified.
The magnetic field generated by this generates an electromagnetic force acting toward the center of the molten metal column surface, thereby holding the molten metal column in the space.

In order to hold the sides of the molten metal column vertically, a large centripetal force is applied to the lower part of the molten metal column to counteract the large liquid pressure of the molten metal, and a magnetic flux density is applied to the upper part so that a small centripetal force is generated to counter the predetermined liquid pressure. It is necessary to adjust the magnetic flux density, and an electromagnetic shielding ring is used to adjust this magnetic flux density.

However, when a power outage occurs during casting in such an electromagnetic field casting method, the unsolidified molten metal cannot be held by the electromagnetic force described above, and the molten metal flows downward. In such a situation, the flowing molten metal would trap moisture on the bottom plate or the surface of the casting pit, causing rapid vaporization of the moisture, posing the risk of an explosion. Furthermore, since the supply of molten metal from the nozzle leading from the tub to the mold does not stop, the amount of molten metal flowing out further increases.

Conventionally, there has been no effective countermeasure against such problems in electromagnetic casting.

[Problems to be Solved by the Invention] In view of these circumstances, the present invention provides an electromagnetic field casting method that can prevent the risk of explosion due to leaking molten metal and cooling water even if a power outage occurs during casting in the electromagnetic field casting method. The purpose is to provide law.

[Means for Solving the Problems] In order to solve the above problems, the present inventor has conducted repeated research, and for this purpose, a heat insulating material is placed inside the electromagnetic shield ring, and this is used to prevent power outages. In some cases, it has been found that it is effective to press the ingot with compressed air, leading to the present invention.

That is, the present invention supplies molten metal into an annular electromagnetic inductor, holds and molds the molten metal into the shape of an ingot, and adjusts the shape with an electromagnetic shielding ring disposed inside the electromagnetic inductor. In this method, in which ingots are continuously cast by water cooling from the side of the ingot, a heat insulating material is arranged in a ring shape on the inner surface of the electromagnetic shielding ring, and when the electromagnetic inductor stops working, the insulating material is perforated in the electromagnetic shielding ring. This is an electromagnetic field casting method characterized by preventing molten metal leakage by letting compressed air flow out from an air outlet and pressing the lower end of the insulating material against the side surface of the ingot.

The electromagnetic field casting device used in the present invention has a heat insulating material annularly disposed on the inner surface of the electromagnetic shield ring in the known casting device, and the lower end of this heat insulating material is pressed against the side surface of the ingot during a power outage. It is characterized in that a compressed air supply pipe leading to a compressed air reservoir is connected to an air outlet bored at an appropriate location in an electromagnetic shielding ring through an actuated valve.

As the heat insulating material used in the present invention, a heat insulating felt material such as fiber or flux is used.

[Example] Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 is an overall sectional view of an electromagnetic casting apparatus for explaining the electromagnetic casting method of the present invention, and FIG. 2 is a sectional view of the electromagnetic casting apparatus during a power outage.

In Figure 1.2, l is the stopper, 2 is the molten metal in the tub, and 3
is a bucket, 4 is a heat insulator, 4° is its lower end, 5 is an electromagnetic shield ring, 6 is an air supply pipe, 7 is compressed air, 8 is a water cooling jacket, 9 is an air outlet, 10 is a cooling water outlet, 1
1 is an electromagnetic inductor, 12 is a nozzle, 13 is a molten metal, 14 is a molten metal solidification section, 15 is air, and 16 is a molten metal scattering particle.

In the electromagnetic field casting method of the present invention, when a power outage occurs during casting work, the electromagnetic force of the electromagnetic inductor 11 disappears. Then, as shown in FIG. 2, the molten metal 13, which had been maintained at a height of 30 to 40 m+1, begins to spill down. However, at the same time as the power outage, a valve leading to a compressed air reservoir (not shown) opens, and compressed air is blown out from the compressed air supply pipe B through the air outlet 9 formed in the electromagnetic shielding ring 5, and is distributed on the inner surface of the ring. The lower end of the provided heat insulating material is pressed against the skin of the ingot formed by solidification of the molten metal. This prevents most of the molten metal from spilling out, and the molten metal that leaks from gaps in the insulation material is also scattered by the compressed air, turned into particles, and blown into the ingot cooling water, where they are cooled and solidified.

Note that leakage of the molten metal can be prevented by widening the interval 17 at the lower part of the heat insulating material, as shown in FIG. 3, at some of the corners of the heat insulating material.

In addition, the stopper is closed at the same time as the power outage, and the supply of molten metal is stopped.

The molten metal thus held by the heat insulating material is gradually solidified by the cooling water.

[Effects of the Invention] As is clear from the above explanation, according to the electromagnetic field casting method of the present invention, even in the event of a power outage, it is possible to avoid the risk of a large amount of molten metal entering the cooling water and causing an explosion. Even if molten metal leaks from the material seal, this small amount of leakage is immediately blown away into particles using compressed air.
In that state, it can be rapidly solidified by cooling water, so there is no risk of explosion.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view explaining the electromagnetic casting device used in the electromagnetic casting method of the present invention, Figure 2 is a cross-sectional view explaining the operation during a power outage, and Figure 3 is the arrangement of heat insulating material in a part of the corner. FIG. 4 is a diagram illustrating a conventional electromagnetic field casting device. 4... Insulation material, 4°... Lower end portion, 6... Compressed air pipe, 9... Compressed air outlet. Figure 2 O 3Pj Figure 4

Claims (1)

[Claims] Supplying molten metal into an annular electromagnetic inductor, holding and molding the molten metal into the shape of an ingot, adjusting the shape with an electromagnetic shielding ring disposed inside the electromagnetic inductor, and cooling the ingot with water from the side surface. In the method of continuously casting ingots, a heat insulating material is arranged in a ring shape on the inner surface of the electromagnetic shield ring, and when the electromagnetic inductor stops working, compressed air is released from the air outlet drilled in the electromagnetic shield ring. An electromagnetic field casting method characterized by preventing molten metal leakage by letting the molten metal flow out and pressing the lower end of the insulating material against the side of the ingot.