JPS5921256B2 - electromagnetic stirring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic stirring device with good heat shielding and waterproof structure.

Recently, there has been a strong trend towards labor saving and energy saving in the steel industry, and as part of this trend, continuous casting equipment that continuously casts thick steel plates has come into widespread use.

However, in continuous casting equipment, since the cast product is cooled and solidified from the outside, segregation and cavities may occur in the center of the cast product.

Materials with such segregation or four cavities cause material defects in the subsequent rolling process, etc., which is not preferable in terms of quality control of processed products.

Therefore, in the continuous casting process, the internal molten metal part is stirred by electromagnetic force.

A so-called electromagnetic stirring device is used to improve quality.

However, when a continuous casting apparatus is provided with an electromagnetic stirrer, which is an electromagnetic device, there are problems with heat shielding from the cast product and a waterproof and watertight structure.

In addition, cooling inside the electromagnetic stirring device and prevention of dew condensation also pose problems.

FIG. 1 shows an example of the configuration of an electromagnetic stirring device for a continuous casting apparatus according to the prior art.

The cast product 1//i is guided by the row 22 and moves while being cooled.

The stirrer 3 is installed at an appropriate position where the inside of the cast product 1 is still in a molten state, is equipped with an iron core 4 that generates a moving magnetic field and an excitation coil 5, and is covered with an outer sheath 6 that has waterproof and heat shielding functions. , The internal molten metal is stirred by its electromagnetic action.

Since the stirrer 3 used for such purposes is an electric device, high temperatures are not allowed inside the stirrer 3, and entry of fragments of the cast product 1 or water for cooling is also not allowed.

Therefore, in order to remove and cool the inside of the stirrer 3 from the heat generated due to copper loss and iron loss, a cooling system using gas circulation is adopted.

In addition, as a measure against coil insulation damage caused by condensation inside the stirrer,
Dry gas may be circulated to prevent dew condensation and to cool the iron core 4 and coil 5.

Furthermore, in addition to gas cooling, there is also one that uses the coil 5 as a hollow conductor to perform direct water cooling.

Electromagnetic stirring devices used in such atmospheres are waterproof,
In addition to heat shielding, a complex cooling configuration is adopted for internal cooling, using a combination of gas cooling and water cooling, making the main body structure and attached equipment complex.

The purpose of the present invention is to realize a highly reliable electromagnetic stirring device that is heat shielding, waterproof, prevents condensation, and simplifies the internal cooling structure.

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3.

The iron core 4 and coil 5 of the stirrer 3, which faces the cast product 1 and generates a moving magnetic field, have the same structure as in the prior art.

However, the coil 5 employs an internal water cooling method using a hollow conductor 50.

Further, the iron core 4 has a water cooling pipe 41 branched from a water supply pipe 40 disposed therein, and an internal cooling method is adopted.

The outer sheath 60 is made of non-magnetic material, and has an outer shield wall 661.
It has a double wall structure of an inner side wall 62 and an inner side wall 62.

It is designed to be cooled by passing cooling water.

The iron core 4° coil 5 inside the agitator 3 surrounded by the outer sheath 60, the coil cooling water supply pipe 51, the water supply branch pipe 52 composed of an assembly, and the coil connection connecting the water supply branch pipe 52 and the coil 5. band 53, further iron core cooling water supply pipe 40, water cooling pipe 4
1, etc. are integrally filled with a wire filling material 1 and molded.

This insulating filling 1 may be made by placing the iron core 4, coil 5, etc. in the outer sheath 60, and then injecting liquid insulating resin and solidifying it by heating and drying, or by placing it in another container (not shown). ) Insert the K iron core 4, coil 5, etc., inject liquid insulating resin, solidify by drying, and then
It may also enter the outer jacket 60.

Next, the effect will be explained.

First, the outer jacket 60 has a heat shielding effect against the heat applied to the cast product 1 whose surface temperature is 900 to 1000°C, and protects the iron core 4 and the coil 5 from being affected by heat.

This is because the outer sheathing wall 61 of the double-walled outer sheath 60
This is because the water flowing between the inner edge wall 62 and the inner edge wall 62 cools and removes heat.

When cooling the inside of the stirrer 3, heat generated by copper loss is removed from the coil 5 by cooling water passed through the hollow conductor 50, and iron loss generated in the iron core 4 is cooled by cooling water passed through the water cooling pipe 41. be done.

Therefore, the stirrer 3 can be placed close to the high-temperature product 1Vc, which is an effective structure in terms of heat shielding and cooling.

Let's also think about waterproofing, watertightness, and dew condensation.

Since the double-walled jacket 60 is made of a non-magnetic plate material, watertightness is naturally maintained.

In addition, since the coil 5 is molded with a solid insulating filling 7, there is no direct condensation on the coil 5.
Therefore, there is no need to worry about a drop in insulation resistance.

There is no need to worry about damaging the insulation.

In this way, this embodiment not only overcomes the drawbacks of the prior art, but also can be completely water-cooled in terms of cooling.
No blower is required, making it simpler than conventional systems that use water cooling and gas cooling together.

FIG. 4 shows another embodiment.

In this case, a liquid refrigerant path is not formed in the coil 5 and the iron core 4, but instead a cooling pipe 71 is provided that passes cooling water in the vicinity of the liquid refrigerant path.
and coil 5. Insulating filling T integrated with iron core 4 etc.
The structure is filled with and molded with.

Of course, it does not matter if it is used in combination with direct cooling.

Even in this way, the objective can be achieved.

There are various methods for injection molding the liquid insulating resin that is injected to form the insulating filler 7, but if air bubbles remain inside, heat conduction will deteriorate and the cooling effect will decrease, so resin injection using the vacuum impregnation method is preferred. Law is preferable.

Furthermore, since the thermal FJ coefficients of the injected resin and the iron core 4, coil 5, etc. are different, if a caking substance called a filler in the form of fibers or pieces of lJ is injected together with the resin, the flexibility against thermal elongation will increase. , cracks appear, and reliability increases.

Jacket 60 and coil 5. The insulating filling 7 molded with the iron core 4 does not need to be integrated.

On the contrary, if a gap is provided, the outer cover 60 and the insulating filler 7
When there is a temperature difference between the two, it is advantageous in that the thermal elongation is not restricted to each other.

Also, the coil 5 and iron core 4 are cooled without using water.

Insulating oil etc. may also be used.

1. The present invention is not limited to the embodiments described above and shown in the drawings, and the present invention is not limited to the embodiments described above and shown in the drawings.
Of course, it can be implemented with various modifications.

As explained above, according to the present invention, the coil, the iron core, and the outer sheath can all be realized by liquid cooling, so that it is possible to realize an electromagnetic stirring device that is small and has a large capacity.

Furthermore, since gas cooling is not required, accessory equipment with large volumes such as the blower can be omitted.

In addition, there is no need to worry about the insulation resistance of the coil decreasing due to dew condensation, etc.
It becomes possible to realize an electromagnetic stirrer that has high reliability over a long period of time.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing a conventional electromagnetic stirring device, Fig. 2 is a cross-sectional view showing an embodiment of the electromagnetic stirring device of the present invention, and Fig. 3 is a cross-sectional view taken along the line A-A in Fig. 2. 4 are sectional views showing other embodiments. 1... Equipment, 3... Stirrer, 4...
・Iron core, 5... Coil, 7... Insulating filling, 40... Water supply pipe, 41... Iron core cooling pipe, 50... Hollow conductor, 51... Water supply pipe, 52... Branch pipe, 53... Coil connection band, 60... Outer covering.

Claims (1)

[Scope of Claims] 1. An electromagnetic stirring device that is disposed at a position where an unsolidified part exists in a cast product by continuous casting and is equipped with an iron core and a coil to electromagnetically stir the unsolidified part. The pipes that form the cooling medium passage for cooling are integrally molded with an insulating filling, and then covered with a double-wall structure jacket made of a non-magnetic material, consisting of an outer wall and an inner wall.
An electromagnetic stirring device characterized by a cooling medium passage between two shield walls. 2. The electromagnetic stirring device according to claim 1, wherein a refrigerant is passed through the interior of at least one of the iron core and the coil for direct cooling. 3. The electromagnetic stirring device according to claim 1 or 2, wherein a liquid is used as a cooling medium for the iron core and the coil.