JPH0817569B2 - Annular flow linear induction electromagnetic pump - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear induction electromagnetic pump for conveying molten metal such as molten metal sodium and molten aluminum.

[0002]

2. Description of the Related Art Transfer of molten metal is carried out, for example, in a nuclear reactor (FB).
In R), in order to convey molten metal sodium,
Further, in the field of casting and the like, in order to convey molten aluminum or the like, a linear induction electromagnetic pump that applies a thrust to the molten metal by an electromagnetic induction action is widely used. Such a linear induction electromagnetic pump is disclosed in, for example, Japanese Patent Publication No. 4-52708.
No. Gazette, Jikken 3-869, and Jikken 1
No. 35597 . These lini
(A) In the induction electromagnetic pump, an inductor including a stator core and a coil for generating a moving magnetic field is arranged on the outer periphery of a duct pipe through which molten metal flows, and a magnetic core is arranged inside the duct pipe.

Examples of conventional external type electromagnetic pumps and immersion type electromagnetic pumps are shown in FIGS. 6 (a), 6 (b) and 7 attached.
They are respectively shown in (a) and (b). Outer circumference of duct pipe 1
An inductor 4 composed of a coil 2 and a stator core 3 is arranged in the, and a core 6 is arranged in the center of the cross section of the duct pipe 1. In each of these conventional electromagnetic pumps, the duct pipe 1
The magnetic flux generated from the inductor 4 arranged on the outer peripheral side of passes through the internal flow path of the duct tube 1, that is, the annular molten metal flow path formed between the duct tube 1 and the core 6. This place
If the duct pipe 1 does not block the magnetic flux, the duct pipe 1
Is formed of a non-magnetic material such as ceramics or stainless steel . Further, the core 6 made of iron which is a magnetic material disposed to form a magnetic path in the duct pipe 1
The protective tube 5 for protection is also made of non-magnetic material such as stainless steel.
Has been.

[0004]

THE INVENTION An object to be solved] The conventional annular channel linear induction electromagnetic pump places the inductor comprising a coil on the outer peripheral side of the duct tube to be a flow path of the molten metal, a separate core within the duct tube Must be placed. Therefore, the outer diameter of the pump is structurally increased. Especially in the immersion type electromagnetic pump, it is necessary to cover the inductor with a protective container.
The outer diameter of the electromagnetic pump becomes large.

Therefore, an object of the present invention is to provide an annular flow path linear induction electromagnetic pump which does not have a large outer diameter structurally in view of the above problems in the prior art.

[0006]

[Means for Solving the Problems] That is, in order to achieve the above-mentioned object, an annular flow path linear induction electromagnetic pump according to the present invention has a flow path having an annular cross section, one end side is closed and the other end side is
Insert the open protective tube into the inside from the upper end side of the outer peripheral tube,
Form a flow path with an annular cross section between this protective tube and the outer peripheral tube ,
The protective tube is made of a non-magnetic material, an inductor for generating a moving magnetic field in the flow path is housed inside the protective tube, and at least a portion of the outer peripheral tube around the inductor is made of a magnetic material. To do. In this case, it is advisable to provide a cooling duct for introducing the cooling fluid from the opened one end side to the inductor side in the protection tube. A heater for heating the inner surface of the protective tube may be provided inside the protective tube.

[0007]

Operation The above-mentioned annular flow path linear induction electromagnetic pump of the present invention
Then, an inductor for generating a moving magnetic field in the annular flow passage and applying thrust to the molten metal was placed in a non-magnetic protective tube .
Therefore, the magnetic field generated from the inductor is formed outside the protection tube.
You can Then, to form the flow path of the molten metal on the outside of the protective tube, by an external tube on the outside of the protective tube and magnetic, external tube itself off the flow path
The porcelain circuit for forming the magnetic path of the magnetic flux
It will be elementary . For this reason, it is not necessary to separately arrange a core in the flow path as in the case where the flow path for the molten metal is provided inside the inductor. Therefore, since the magnetic path is formed so as to have a small diameter as a whole and traverse the flow path of the molten metal, the annular flow path linear induction electromagnetic pump having a sufficient driving force can be obtained.

Further, the protective tube accommodating the inductor has one end
Only the inside is closed because the other end is open
Dissipate heat inside the protection tube to prevent the inductor from overheating
be able to. In particular, the protective tube, the cooling duct is provided for introducing a cooling fluid to cool the inductor therein Turkey
To force the inductor to cool with a cooling liquid and heat it.
Can be reliably prevented. Further, in this case, in the case where a heater for heating the inner surface of the protection tube is provided inside the protection tube, the protection tube is cooled by the cooling fluid, and the molten metal is cooled and solidified on the surface. To be prevented.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows the structure of an immersion type annular flow path linear induction electromagnetic pump for molten aluminum according to an embodiment of the present invention. In Figure 1, reference numeral 10 is a molten aluminum alloy stored in the container (not shown). 4 protruding from the outer peripheral tube 20 to the outside
It is fixed on the lids 11 and 11 of the container by the projections 21, 21 ... at several places, and the opening 22 at the lower end thereof is arranged so as to be positioned below the lowest level of the level fluctuation range d of the molten aluminum alloy 10. ing. The outer peripheral tube 20 is made of a magnetic material such as cast iron and has a double-walled structure at its lower portion. An opening 23 is formed above the outer peripheral pipe 20, and a molten metal discharge port 24 is formed on the upper side wall thereof. Reference numerals 25 and 26 in FIG. 1 are preheating heaters provided inside for heating the outer peripheral tube 20.

Inside the outer peripheral tube 20, a heat-resistant protective tube 30 made of non-magnetic ceramics or the like is inserted from an upper opening 23 thereof, and the protective tube 30 and the outer peripheral tube 20.
A flow channel 40 having an annular cross section for flowing an aluminum alloy, which is a molten metal, is formed between and. Inside the tubular protection tube 30, an inductor 50 having a coil 52 wound around the outer periphery of a stator core 51 as shown in FIG. 3 is arranged. The inductor 50 is for generating a moving magnetic field in the annular flow passage 40 and applying a thrust to the molten metal. The inductor 50 is fixed to the outer peripheral side of the tip of a tubular cooling duct 60 inserted in the center of the protective tube 30 .
In this inductor 50, the cooling duct 60 is inserted from the upper opening of the protection tube 30, and the flange on the upper end side is protected by the protection tube 30.
Supports the upper flange of 30 to protect the cooling duct 60
It is attached to the lower end of the protective tube 30 by suspending it at the center of the tube 30.

FIG . 2 shows a protective tube 3 incorporating the inductor 50 .
The zero tip portion is shown. As shown in the figure , inside the protective tube 30, for example, a tube 31 made of SUS304 ,
A heater 32 wound around the outer periphery of its being disposed and the heat insulating material 33, the inductor 50 is disposed inside the heat insulating material 33. In addition, reference numeral 34 in FIG.
It is a heat insulating material inserted at the tip of 0, and the arrow shows the cooling duct.
2 shows the flow of air, which is a cooling fluid, sent under the protection tube 30 through a gate 60.

In FIG. 1, reference numeral 70 designates the outer peripheral tube 20.
It is a duct pipe for guiding the molten metal laterally from the discharge port 24 formed in the side wall of the. The duct tube 70 is connected to the outer peripheral tube 2 by a spring (not shown) through a pressing metal fitting 71 and a connecting ring 72 attached to the lid 11 of the container, and a packing 73 attached to the discharge port 24.
0 is pressed in the direction indicated by arrow P (to the right in the figure)
I have. As a result, the connecting portion is sealed. Further, the flange portion at the upper end of the protection tube 30 is also in contact with the edge portion of the upper end opening of the outer peripheral tube 20 with the packing 35 sandwiched therebetween. The protection tube 30 is pressed in the direction indicated by arrow P (downward in the figure) by a spring (not shown). As a result ,
The upper end is sealed. Further, reference numeral 74 in the drawing is a heater for heating the side duct pipe 70,
The heater 74 is embedded in a heat insulating material 80 that entirely covers the induction electromagnetic pump.

In such an immersion type annular flow path linear induction electromagnetic pump, a flow path of molten metal is formed between the protective tube 30 and the outer peripheral tube 20, the inductor 50 is arranged inside the flow path, and the inductor 50 is arranged outside the flow path. By arranging the outer peripheral tube 20 made of a magnetic material, the outer peripheral tube 20 itself can have a function as a porcelain circuit element . This eliminates the need for a core that has to be separately installed in the molten metal channel. Therefore, the number of parts is reduced, and a small annular flow path linear induction electromagnetic pump can be obtained.

The magnetic outer tube 20 functioning as a porcelain circuit element is preferably provided with a ceramic coating on the contact surface with molten aluminum in consideration of corrosion resistance.
Further, for example, when the molten metal is an aluminum alloy, the temperature thereof is equal to or higher than the Curie point of ordinary cast iron. Therefore, it is preferable to add Co or the like to the cast iron forming the outer peripheral tube 20 to raise the Curie point. On the other hand, the protection tube 30 should not block the magnetic flux.
There way, ceramic is a non-magnetic material, for example, good Si ₃ N ₄ corrosion resistance to aluminum or,, S
It is preferably formed of i-Al-O-N ceramics or the like.

Further, according to the structure of the above annular flow path linear induction electromagnetic pump, the coil 52 is exposed to high heat by arranging the inductor 50 composed of the stator core 51 and the coil 52 in the central portion of the cross section of the outer peripheral tube 20. Will be done. Regarding this, by supplying cooling air to the inside of the protection tube 30 that protects the inductor 50, high heat is generated.
You can prevent obstacles . In this case, in order to hold the stator core 51 of the inductor 50 inside the protection tube 30,
A cooling duct 60 can be used to supply this cooling air. Further, when the cooling structure of the coil 52 is adopted, as shown in FIG. 2, the surface of the protection tube 30 is cooled so that the molten metal does not solidify on the surface.
It is preferable that a heater 32 is attached to the inner peripheral surface of the protective tube 30 to heat it, and a heat insulating material is inserted between the heaters 32 to thermally block the heat.

Next, FIG. 4 shows a submerged annular flow path linear induction electromagnetic pump for molten sodium which is another embodiment of the present invention. This example conveys molten sodium
Immersion type annular channel linear induction electromagnetic pump for molten sodium
It is That is, the molten sodium 100 is stored inside the sodium tank 120 made of stainless steel ,
The molten sodium is taken out by inserting a submerged annular flow path linear induction electromagnetic pump from above the tank 110. The structure and operation of the immersion type annular flow path linear induction electromagnetic pump of this embodiment are basically the same as those of the immersion type annular flow path linear induction electromagnetic pump for molten aluminum shown in FIG. Particularly in this embodiment, the outer peripheral tube 20 'and the protective tube 3 are
0'is integrally formed of a non-magnetic stainless material. It
In addition, a tubular member 200 made of a magnetic material such as iron or cast iron is housed inside the outer peripheral tube 20 '. Reference numeral 1 in the figure
10 is a heater arranged outside the sodium tank 120.

FIG . 5 shows another embodiment of the present invention. This embodiment is an example in which the present invention is applied to a so-called external annular flow path linear induction electromagnetic pump, which is different from the immersion type annular flow path linear induction electromagnetic pump of the above-described embodiment. The external annular flow path linear induction electromagnetic pump of this embodiment has a disconnection formed between the outer peripheral tube 20 ″ and the protective tube 30.
A ring-shaped flow passage is placed in the middle of a duct that conveys molten metal
From the downstream side (left side in the figure), the outer peripheral tube 20 " and the protective tube 3
Supplied to the upstream side is given a thrust (upper right side in the drawing) to the molten metal, such as flowing as Zn between 0. The operation principle and structure are basically the same as those of the above-mentioned embodiment. However, in this embodiment, the supply duct pipe 120 for guiding the molten metal from the downstream side, the outer peripheral pipe 20 ″ forming the linear induction electromagnetic pump, and the discharge port formed in the side wall of the outer peripheral pipe 20. 125 is integrally formed of cast iron which is a magnetic material.

Such an external annular flow path linear induction electromagnetic pump as described above can also be applied to molten aluminum. In that case, a casting having relatively good corrosion resistance may be used for the outer peripheral tube 20 ". Further, in order to improve the corrosion resistance,
Used with a ceramic coating on the contact surface . For Zn or Sn, steel is used, and for Na, a steel duct tube with Ni or stainless clad on the inner peripheral surface is used . It should be noted that the protective tube 30 ″ that covers the inductor 50 disposed inside the outer peripheral tube 20 ″ must be non-magnetic, for example, for aluminum transportation, it is non-magnetic.
Nickel resist cast iron (Ni-Resist cast iron)
In the case of carrying solder, Zn, Na, etc., for example, S
Non-magnetic stainless steel such as US316 is used. In particular, in the case of transporting Zn, it is preferable to use a ceramic protection tube having excellent corrosion resistance. Note that FIG.
Reference numeral 300 denotes a preheating heater disposed outside the supply duct pipe 120, the outer peripheral pipe 20 ″, and the discharge port 125.

[0019]

As is apparent from the above description, the outer peripheral tube forming the annular flow path of the molten metal has a function as a porcelain circuit element , so that the core is arranged in the flow path of the molten metal. There is no need, the number of parts is reduced, and a small annular flow path linear induction electromagnetic pump can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing a structure of an immersion type annular flow path linear induction electromagnetic pump for molten aluminum which is an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a partially enlarged structure of the annular flow path linear induction electromagnetic pump of FIG.

3 is a perspective view showing a structure of a stator core and a coil of the annular flow path linear induction electromagnetic pump of FIG.

FIG. 4 is a sectional view showing the structure of a submerged annular flow channel linear induction electromagnetic pump for molten sodium which is another embodiment of the present invention.

FIG. 5 is a cross-sectional view showing the structure of an external annular flow path linear induction electromagnetic pump that is another embodiment of the present invention.

FIG. 6 is a cross-sectional view showing the structure of a conventional external annular flow path linear induction electromagnetic pump.

FIG. 7 is a cross-sectional view showing the structure of a conventional immersion type annular flow path linear induction electromagnetic pump.

[Explanation of symbols]

20, 20 ', 20 "Peripheral tube 30, 30', 30" Protective tube 32 Heater 40 Annular flow path 50 Inductor 51 Stator core 52 Coil 60 Cooling duct

Claims (3)

[Claims] 1. An annular flow path linear induction electromagnetic pump having a flow path having an annular cross section and an inductor for generating a magnetic field moving in the central axis direction of the flow path, the lower end side being closed,
Insert the protective tube with the upper end open from the upper end of the outer peripheral tube
Inserted, forming a flow path having an annular cross section between the protection tube and the outer peripheral tube , the protection tube is made of a non-magnetic material, and an inductor for generating a moving magnetic field in the flow path is housed inside the protection tube. An annular flow path linear induction electromagnetic pump, wherein at least a portion of the outer peripheral tube around the inductor is made of a magnetic material. 2. The annular flow path linear induction according to claim 1, wherein a cooling duct for introducing a cooling fluid from the open upper end side to the inductor side therein is provided in the protection pipe. Electromagnetic pump. 3. The annular flow path linear induction electromagnetic pump according to claim 2, wherein a heater for heating the inner surface of the protection tube is arranged inside the protection tube.