JPS5840488A - Electromagnetic agitator for molten metal - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mechanism for arranging an electromagnetic stirring device for molten metal (hereinafter referred to as molten metal) accumulated in a container.

For example, in an aluminum reverberatory furnace (one specific configuration of a molten metal container) I, after a certain amount of molten metal has accumulated, the aluminum material to be melted is immersed in the molten metal, and the air is shut off (for the purpose of preventing oxidation). ) and roasted. In this process,
The temperature of the molten metal surrounding the aluminum material to be melted is lower than that of the molten metal in other parts, and in order to increase the melting efficiency of the material to be melted, the pot is a means for crabs that inevitably requires a stirring action. For example, an inductor for generating a moving magnetic field is placed at the bottom of a reverberatory furnace, and the moving magnetic field generated by this inductor is applied to the infiltration in the furnace, giving a thrust to the molten metal and stirring it. is possible. The main parts of this configuration are as shown in FIG. In Fig. 1, the refractory furnace molten metal holding part is surrounded by a refractory material 1a with an outer sheath lb (usually a member board). Reference numeral 2 denotes an inductor, which is disposed at the bottom of the furnace.A jacket 1b facing the inductor 2 is made of a non-magnetic material, such as stainless steel 1b', in order to prevent magnetic short circuits. 3 is molten aluminum, 4
is the aluminum material to be melted.

By the way, at the distance GO between the surface of the inductor 20 and the molten metal 3 in the furnace in FIG. 1, the following relational expression holds true.

BG-B. . [→・Go) ,
++' , , , , , u) Here, 2 BG...Magnetic flux density BO on the molten metal surface closest to the inductor...
- Magnetic flux density τ on the surface of the inductor - Pitch of the ball On the other hand, the magnetic flux density BG required for stirring is fixed.

Even if the distance GO changes, it is necessary to maintain a value above a certain value. Therefore, as the distance aO increases, the magnetic flux density BG decreases in equation Q), so the magnetic flux density BO on the inductor surface
It must be increased to compensate for the exponential decay of the magnetic flux density BG.

However, when holding molten metal in a container, the thickness of the refractory material 1a is required to be more than a certain level from the viewpoint of strong heat retention and prevention of leakage, and this requires a considerable value of magnetic flux density on the surface of the inductor. As a result, as the inductor 2 becomes larger, there is a drawback that the efficiency decreases significantly. One possible way to eliminate this drawback is to reduce the above distance GO by burying the inductor in the furnace wall, but with this configuration, there is a risk that the expensive inductor will be damaged by the molten metal. This poses a problem in practicality because it causes noise and noise and makes it impossible to maintain and inspect the inductor.

The purpose of this invention is to cut out the container fireproof wall only at the location where the inductor is installed, and by placing the inductor in this notch, it is possible to maintain and inspect the inductor while maintaining its strength, heat retention effect, and leakage prevention effect. Therefore, it is an object of the present invention to provide an electromagnetic stirring device for molten metal that can efficiently operate an inductor.

The illustrated embodiment will be specifically described below. Second
The figure is a sectional view of a main part of the apparatus according to the present invention, and elements equivalent to those in FIG. 1 are designated by the same reference numerals. In FIG. 2, the IC is a recessed part, a refractory material 1a is cut out, and the periphery is lined with a non-magnetic material (usually a stainless steel material).

The inductor 2 is inserted into and inserted into the recessed fitting portion 1c). At this time, the distance G1 from the surface of the inductor 2 to the bath water 31 is optimal (inductor 2
(determined based on a comparison between the thrust applied to the molten metal 3 and the prevention of leakage). In some cases, cold air may be blown into this recessed part 1o to prevent the solidification of cloudy molten metal in the unlikely event of a leakage accident (particularly an accident at the recessed part 1C of a fireproof wall mill). It is also possible to prevent accidents. 4
is the aluminum material to be melted.

Structure of the above-mentioned embodiment) Here, the molten metal 3 is maintained at a high temperature by a burner device (not shown), and the aluminum material 4 to be melted poured into the molten metal 3 is kept in the molten metal while being cut off from the outside air. It takes heat from 3 and melts it, and then it is made into a cloth. Therefore, when an AC voltage is applied to the coil of inductor 2,
A magnetic flux straddles the magnetic poles forming a one-pole pitch, and the magnetic flux advances as the voltage phase changes, so that a so-called moving magnetic field acts on the molten metal 3, and the eddy current generated in the molten metal 3 and the moving magnetic field are The molten metal 3 receives thrust from the electromagnetic pot and is stirred. As a result, the low-temperature molten metal surrounding the aluminum material 4 to be melted is replaced with another high-temperature molten metal, and the melting action of the aluminum material 4 to be melted is promoted.

t31L FIG. 4 shows another embodiment of this invention,
First, in FIG. 3, the inductor 2 is arranged so as to be insertable into a recessed fitting part 1c formed on the side surface of a molten metal container 1 such as a reverberatory furnace. The operation in this case is equivalent to that of the apparatus shown in FIG. 2, in which the molten metal 3 is stirred from the side by arranging an inductor to promote the flow of the molten metal.

Next, the configuration shown in FIG. 4 shows an embodiment of the present invention for a tilting furnace in which molten metal held inside is poured into the outside by tilting. That is, the molten metal container 1 includes a tilting shaft 6 supported on a pedestal 5 and a cylinder 7 that supports the container 1 together with the tilting shaft 6. It forms part 1c. When the molten metal container 1 is in a substantially horizontal state when no molten metal is being poured, the inductor 2
(attached to the pedestal 5) is arranged so as to fit within the recessed fitting portion 1c.

Note that the present invention is not limited to the above-mentioned reverberatory furnace, but can be applied to stirring of molten metal in any molten metal container.

As described above, the electromagnetic stirring device for molten metal according to the present invention has a structure in which a container holding the molten metal is provided with an inductor for stirring the molten metal. It is formed on the wall.

Based on this configuration, the moving magnetic field from the inductor
The length of time it takes to reach this point is short. Along with this, the inductor does not have to increase its capacity (it can provide a strong thrust to the molten metal and obtain sufficient electromagnetic stirring force.Moreover, if you regularly check for leaks in the recessed part, In other parts, the wall thickness of the container is sufficient in relation to the heat retention effect, so it has excellent features such as there is almost no risk of accidents due to water leakage.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part of a reverberatory furnace equipped with a conventional electromagnetic stirring device, and FIGS. 2, 3, and 4 are sectional views showing embodiments of the present invention. 1... Reverberatory furnace molten metal holding part (container) 1c... Recessed fitting part 2... Inductor 3... Molten metal applicant Shinko Electric Co., Ltd. agent Patent attorney Haruyayo Saito / Figure 'M 2 figure

Claims (1)

[Claims] 1. In a configuration in which a container holding molten metal is provided with an inductor that exerts a thrust on the molten metal and stirs the molten metal, the outer surface of the part of the fireproof wall of the container where the molten metal contacts the inner surface thereof An electromagnetic stirring device for molten metal, characterized in that a recessed part is formed along the line, and the inductor is disposed within this recessed part.