JPS5857678B2 - electromagnetic stirring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic stirring device used, for example, to improve the quality of steel products.

Recently, in order to improve the quality of steel materials, a method of electromagnetically inductively stirring a molten metal or an internally molten metal to be stirred has been put into practical use.

This electromagnetic stirring device has coils excited by multiphase AC power wrapped around a stratified iron core, similar to the stator of a normal two-pole induction motor, and these coils are housed in a protective outer box to protect them from water droplets and dust. It is composed of

The inner cylinder of the protective outer box, which faces the molten metal, is usually made of a non-magnetic material such as stainless steel so that the magnetic force from the electromagnetic stirrer reaches the molten metal with little loss.

However, when using an electromagnetic stirrer, the molten metal is at a high temperature of several hundred degrees, so the radiant heat heats up the inner cylinder of the protective outer box particularly strongly, and the conduction of this heat damages not only the inner cylinder of the protective outer box but also the bottom plate and The lid also gets hot, reaching several hundred degrees.

When the protective outer box becomes hot in this way, even if a heat-resistant material is used for the O-ring used to connect the inner cylinder to the bottom plate and the lid, and an H-class material is used for the coil insulator, There is a risk of thermal deterioration exceeding the thermal usage limit.

An object of the present invention is to provide an electromagnetic stirring device in which the electromagnetic stirrer is surrounded by a protective outer box, and the flow of the cooling medium supplied into the protective outer box is improved to improve the cooling effect of the electromagnetic stirrer and the electromagnetic stirrer. This is what we provide.

The present invention will be described below with reference to embodiments shown in the drawings.

In FIG. 1 and FIG. 2, an electromagnetic stirring device 1 of the present invention is shown.
The device is roughly divided into a combination of an electromagnetic stirrer 2 and a protective outer box 3 that covers the electromagnetic stirrer 2 in a drip-proof and dust-proof manner.

The electromagnetic stirrer 2 is constructed by winding a multiphase coil 5 excited by multiphase AC power around an endless stratified iron core 4 like the stator of a two-pole induction motor, and this is protected via a support ring 6. It is fixed to the outer cylinder 7 of the outer case 3.

The protective outer box 3 includes an outer cylinder 7 that covers the outside of the electromagnetic stirrer 2, and an inner cylinder made of, for example, non-magnetic stainless steel that faces and surrounds the object to be stirred 8, such as a rod-shaped molten metal, of the stirrer 2. 9 and a bottom plate 10 and lid 11 that close the upper and lower ends of the outer cylinder 9°7.

Note that the inner cylinder 9, the bottom plate 10, and the lid 11 are fitted together via a heat-resistant O-ring 12, the outer cylinder 7, the bottom plate 10, and the lid 11 are tightened with bolts 13, and the coil 5 is installed in the outer box 3. Multiphase AC power is supplied from the terminal 14 .

The present invention is characterized in that a cooling medium is supplied and circulated inside the protective outer box 3 to cool the outer box 3 and the electromagnetic stirrer 2, thereby achieving a heat insulating effect against the heat from the stirred material 8. have

That is, the protective outer box 3 has a pipe 15a near the top, as shown in FIG.

4 pipes 15b, 16a, 16b, pipe 17 near the bottom
A total of eight pipes, four pipes a, 17b, 18a, and 18b, are installed in series.

These eight pipes are pipes 15a as shown in FIGS. 1 and 2.

The pipes 16a, 17a, and 18a are refrigerant inflow pipes, and the pipes 15b, 16b, 17b, and 18b are refrigerant outflow pipes.

Note that all eight pipes are not shown in FIGS. 1 and 2 due to the relationship between the mounting positions and cross-sectional locations of the pipes.

These pipes are pipe 15a as shown in FIG.
, 15b, 16a, 16b, 17a, 17b, 18a,
Four systems 18b are connected in parallel to the refrigerant refrigerator 50 and the refrigerant pump 51, and the refrigerant is circulated and supplied as shown by the arrow.

Therefore, in the present invention, each pipe 15a.

15b, 16a, 16b, 17a, 17b, 18a.

As shown in FIG. 2, rectifying plates 19, 20, 21, and 22 are provided at the opening of the protective outer box 3 18b.

That is, the current plates 19 and 20 are the inflow pipes 15a.

The refrigerant discharged from 16a is guided so as to flow on the inner surface of the outer cylinder 7 of the protective outer box 3 as shown by arrow Y, and the rectifying plates 21 and 22 are used to guide the refrigerant so that it flows on the inner surface of the outer cylinder 7. The refrigerant is guided to the outflow pipes 15b and 16b as indicated by arrow Y2.

The rectifying plates 19 to 22 cause the refrigerant to flow in a spiral shape inside the protective outer box 3 without being locally concentrated.

In the electromagnetic stirring device of the present invention configured as described above,
When power is applied to the coil 5 of the electromagnetic stirrer 2, the protective outer box 3
A magnetic flux Φ is generated through the inner cylinder 9 as indicated by the dotted line arrow, and the molten metal to be stirred 8 is electromagnetically stirred by the magnetic force of this magnetic flux Φ, thereby improving its quality.

In this case, the inside of the protective outer box 3 is heated by the radiant heat of the molten metal, but this is cooled by the cooling medium circulating through the outer box 3.

That is, when the refrigerant pump 50 shown in FIG.
a, 16a, 17a, and 18a into the upper chamber A and lower chamber B, which are the coil end portions of the coil 5 of the electromagnetic stirrer 2 in the protective outer box 3.

The refrigerant that has entered chambers A and B passes through the rectifying plate 19.
21, it flows in a spiral shape through the inner surface of the outer cylinder 7, the lid 11, and the bottom plate 10 as shown by the arrow Y1 in FIG.
, 17b, and 18b to the refrigerator 19.

The flow of the refrigerant inside the protective outer box 3 evenly flows through the inside, so that the end portion of the coil 5 of the electromagnetic stirrer 2 and the protective outer box 3 itself are effectively cooled, and the heat from the molten metal cools down the outer box. 3 and the coil 5 can be suppressed from increasing in temperature.

Furthermore, if the refrigerant pressure P1 flowing into the lower chamber B of the protective outer box 3 is made higher than the refrigerant pressure P2 flowing into the upper chamber A, Pl
Due to the pressure difference of -P2=Po, a part of the refrigerant in the lower chamber B flows into the upper chamber A through the gap g between the inner cylinder 9 and the iron core 4, as indicated by arrow Y3.

This flow of refrigerant cools the surfaces of the inner cylinder 9 and the iron core 4, which tend to trap heat.

In the embodiment shown in FIGS. 1 and 2 above, even if the pipes 15b, 16a and the current plate 20.21 are omitted, and a single system is created using the pipes 15a, 16b and the current plate 19.22, The refrigerant flows uniformly inside the protective outer box 3 through the baffle plates 19 and 22 on its inner surface, thereby increasing cooling efficiency.

Furthermore, the inner cylinder 9 of the protective outer box 3 may be made of a fireproof material or a heat-resistant insulator instead of stainless steel, and in this case, the magnetic flux loss of the electromagnetic stirrer 2 can be reduced.

Next, another embodiment of the present invention will be described with reference to FIGS. 4 and 5, but since the same reference numerals as in the embodiment shown in FIGS. 1 and 2 indicate the same parts, the explanation thereof will be omitted. .

In this embodiment, a plurality of ducts 52 for refrigerant passages are provided in the iron core 4 of the electromagnetic stirrer 2, and an upper chamber A is provided in the protective outer box 3.
and refrigerant inflow pipes 54a, 54 opening into the lower chamber B.
b.

54C and 54d are connected, and a refrigerant outflow pipe 53 is connected to a portion of the outer cylinder 7 that roughly corresponds to the back surface of the iron core 4.

Of course, rectifier plates 55 and 56 are disposed at the openings of the inflow pipes 54a to 54d to guide the refrigerant discharged from the refrigerant so that it flows along the inner surface of the protective outer box 3 and toward the outflow pipe 53. are doing.

In this embodiment as well, the refrigerant discharged from each of the inflow pipes 54a to 54d into the upper chamber A and lower chamber B of the protective outer box 3 is moved out of the protected area by the rectifier plates 55 and 56 as shown in FIG. Arrow Y1 flows on the inside of box 3.
The air gap GL between the inner tube 9 of the protective outer box 3 and the iron core 4 is guided from above and below by a matching current plate.

The refrigerant that has passed through the gap g passes through the duct 52 of the iron core 4 to cool it, and then returns to the refrigerator system from the outflow pipe 53.

In this embodiment as well, the refrigerant flows inside the protective outer box 3 in a whirlpool shape to effectively cool the outer box 3 and the coil 5, and also flows through the duct 52 through the gap g and the inside of the iron core 4. The cooling efficiency increases.

Further, in this embodiment, since the outflow pipe 53 is provided at the back of the iron core 4 to draw in the refrigerant, the refrigerant pressure P1 of the upper and lower inflow pipes. There is no need to provide a pressure difference at P2.

As described above, according to the present invention, the electromagnetic stirrer is surrounded by a protective outer box, and a rectifying plate for improving the flow of the refrigerant is provided at the opening of the pipe that supplies refrigerant to the protective outer box. The refrigerant is improved from flowing locally inside the outer box and flows evenly, effectively cooling the outer box and the electromagnetic stirrer, thereby preventing thermal deterioration of the coil insulation etc. due to the heat of the stirred material. I can do it.

Furthermore, by flowing the refrigerant through the gap surface of the iron core and inside the iron core, an electromagnetic stirring device with even higher cooling efficiency can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view showing an embodiment of the electromagnetic stirring device according to the present invention, FIG. 2 is a plan view taken along the line X-X in FIG. 1, and FIG. A system diagram showing the cooling system,
FIG. 4 is a partially cutaway side view showing another embodiment of the present invention, and FIG. 5 is a plan view taken along the line XX in FIG. 4. 1... Electromagnetic stirring device, 2... Electromagnetic stirrer, 3... Protective outer box, 4... Iron core, 5
...Coil, 7...Outer tube, 9...
... Inner cylinder, 8 ... Material to be stirred (molten metal), 10 ...
... Bottom plate, 11 ... Lid, 15 a, 1
6a, 17a. 18 a = refrigerant inflow pipe, 15 b, 16 b
, 17b. 18b...Refrigerant outflow pipe, 19-22...
... rectifier plate, 50 ... refrigerant refrigerator, 51-.
... Refrigerant pump, 52 ... Duct, 53 ...
... Refrigerant outflow pipe, 54a to 54d ... Refrigerant inflow pipe, 55, 56 ... Current plate.

Claims (1)

[Scope of Claims] 1. In a device in which an electromagnetic stirrer is surrounded by a protective outer box and a cooling medium is circulated within the protective outer box, an inlet pipe for the cooling medium is arranged such that an opening faces the protective outer box. and an outflow side pipe, and a first baffle plate that protrudes inward of the protective outer box at the opening of the inflow side pipe and a first baffle plate that protrudes inward of the protective outer box at the opening of the outflow side pipe. An electromagnetic stirring device characterized in that each projecting second current plate is provided. 2. The electromagnetic stirring device according to claim 1, characterized in that the cooling medium has two circulation systems in the upper chamber and the lower chamber of the protective outer box, each of which flows in different directions. 3. A patent claim characterized in that a difference is given to the pressure of the cooling medium in the upper chamber and the lower chamber, and the pressure difference causes the cooling medium to flow into the gap between the protective outer box and the iron core of the electromagnetic stirrer. The electromagnetic stirring device according to scope 1. 4 Open pipes on the inflow side of the cooling medium to the upper and lower chambers of the protective outer box, and open pipes on the outflow side of the cooling medium at the back of the iron core of the electromagnetic stirrer, so that the cooling medium flows through the upper and lower chambers. 2. The electromagnetic stirring device according to claim 1, wherein the cooling medium flows out from the outlet pipe through a gap between the iron core and the protective outer box and the iron core duct.