JPH04164294A - Electromagnetic pump - Google Patents

Abstract

PURPOSE:To enable a temperature rise in an electromagnetic pump to be prevented by providing a fan for the forced circulation of sealed gas through a cable passage, in the cover of the expanded section of a conduit end externally projected from a reactor vessel. CONSTITUTION:The terminal end of a conduit 9 is formed as a large diameter and eccentrically expanded section 9b, and a cylindrical conduit cover 21 is so coupled thereto as to be freely detachable. Furthermore, the internal space of the conduit 9 is divided into cable passages 25 with an axial division 22. Also, the lower section of the inside of the cover 21 is divided into two chambers with a division 27 continuous to the division 22, and an axial flow fan 28 is provided in the chamber at the side of a terminal 24. The fan 28 sucks gas from a passage 25 at the side of the chamber thereof, and blows the gas toward the other passage 25 via the upper space of the cover 21. According to the aforesaid construction, sealed gas is forcibly circulated to the inside of an electromagnetic pump 7, and the convection of the gas is facilitated. Also, the gas under convection exchanges heat with a primary coolant around the conduit 9, thereby cooling an iron core and a coil group.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to an electromagnetic pump used in a fast breeder reactor.

(Prior Art) FIG. 6 is a schematic cross-sectional view showing the schematic configuration of a conventional liquid metal cooled fast breeder reactor. In this figure, a reactor core 2, a primary circulation pump 3, and an intermediate heat exchanger 4 are housed in a reactor vessel 1, immersed in liquid metal sodium 5, which is a coolant (hereinafter simply referred to as the primary coolant). ing. In the fast breeder reactor configured as described above, the secondary coolant 5 is circulated by the primary main circulation pump 3 as indicated by the arrow in the figure.

The heat generated in the reactor core 2 is transferred to the primary coolant, and the high temperature primary coolant is transferred to the secondary coolant (
(not shown), and the temperature is lowered. The primary coolant whose temperature has been lowered returns to the primary main circulation pump 3 again, is sent to the reactor core 2, and repeats the above process.

Conventionally, as the primary main circulation pump 3, a mechanical pump that generates discharge pressure by rotation of an impeller has been employed. This mechanical pump was driven by a main motor 6 installed on the side of the pump.

Since the primary coolant 5 of the fast breeder reactor configured as described above is liquid metal sodium with high conductivity, it is also possible to employ an electromagnetic pump as the primary circulation pump. FIG. 5, in which the same parts as in FIG. 6 are denoted by the same reference numerals, is a schematic cross-sectional view of an example of a fast breeder reactor employing an electromagnetic pump 7 as a primary main circulation pump.

By adopting the electromagnetic pump described above, the installation of the main motor in the upper space 8 of the main circulation pump is omitted, and it is only necessary to arrange the electric conduit for the power cable insertion for the electromagnetic pump 7. The superstructure of is significantly simplified.

Furthermore, the electromagnetic pump 7 is a static device compared to a mechanical pump, and is much easier to maintain. Furthermore, it has no free liquid level and has excellent controllability, and by adopting this, it is possible to improve the reliability of the fast breeder reactor and simplify the configuration.

FIG. 4 is an enlarged longitudinal sectional view of the electromagnetic pump 7. The example shown in this figure is a two-stage electromagnetic pump.
The electromagnetic pump 7 includes a cylindrical inner core 1o and a cylindrical outer core 11, and an inner duct]7 is disposed in contact with the outer circumference of the inner core 10 and an inner duct is disposed in contact with the inner circumference of the outer core ]-1. An annular flow path 12 having an annular cross section is formed between the two iron cores by the outer duct 18 .

An inner coil group 13 including a large number of coils is attached to the outer circumferential surface of the inner core 1o, and an outer coil group 14 including a large number of coils is attached to the inner circumferential surface of the outer core 11.

Note that the inner duct 17 has a central passage 1 concentric with each of the iron cores.
5, the inner cylinder 17a and the portion in contact with the inner core 17 are continuous, and the inner core 17
A space is formed in which the inner coil group 13 is sealed. Furthermore, the outer ducts 1 to 18 also have a concentric outer cylinder 18a, and the outer cylinder 1 to 88 and the part that contacts the inner periphery of the outer core are continuous, and the outer core 11 and the outer coil group 14
It forms a space that is sealed. Note that 19 in the figure indicates a sealed gas.

Note that power is supplied to each coil group by a power cable (not shown) inserted through the electric conduit 9.

In the conventional electromagnetic pump 7, the primary coolant sucked up via the annular flow path 12 by electromagnetic induction flows through the central flow path 15 and is discharged toward the reactor core.

(Problems to be Solved by the Invention) In the conventional electromagnetic pump 7 having the configuration described above, the inner coil group 1 is
3. The outer coil group 14 recovers Joule heat generated during pump operation into the primary coolant in which the electromagnetic pump is immersed, thereby reducing energy loss in the electromagnetic pump.

Therefore, in the above cooling means, the coil groups 13 and 14
The heat dissipation from the inner core 17 and the outer core 18 to the surrounding primary coolant is caused by contact heat transfer between the inner core and the inner duct 17, contact heat transfer between the outer duct 18 and the outer core 11, radiation, This is done only by natural convection of the gas sealed inside the electromagnetic pump, so we cannot expect much from it. Therefore, the temperature of the coil group becomes a high temperature that is 100 to 200''C higher than the surrounding primary coolant temperature (400'C).

However, coil insulation means that can withstand the above-mentioned high temperatures are not currently in practical use.

The present invention has been made based on the above circumstances, and it is possible to recover as much of the heat generated from the coil group into the surrounding primary coolant and to reduce the temperature of the coil group as much as possible. The purpose is to provide electromagnetic pumps.

[Configuration of the Invention (Means for Solving the Problems)] The electromagnetic pump of the present invention has at least two cable passages in a conduit through which an internal cable for feeding power to a group of coils for electromagnetic induction is inserted; An eccentric bulge is provided at the end of the conduit that protrudes outside the reactor vessel, and a cylindrical conduit lid detachably attached to the end allows forced circulation of sealed gas through the cable passage. It is characterized by being equipped with a blower to make the air flow.

(Function) In the electromagnetic pump of the present invention having the above configuration, gas is sucked from the cable passage on the room side in which the blower is installed inside the conduit cover, and is transferred to the other electric wire passage through the upper space in the cover. Squirt towards. As a result, the sealed gas is forced to circulate within the electromagnetic pump. This forced circulation of gas promotes gas convection, and the gas in the convection exchanges heat with the primary coolant around the conduit, thereby cooling the iron core and coil group.

(Embodiment) FIG. 1, in which the same parts as in FIG. 5 and FIG. A sectional view, FIG. 2 is an enlarged vertical sectional view of the main part of the above embodiment, and FIG. 3 is a sectional view of FIG. 2 111-IH.
FIG.

In FIG. 1, a conduit 9 through which a power cable (not shown) that supplies power to the electromagnetic pump 7 is inserted has a different structure from the conduit 9 of the conventional electromagnetic pump 7 shown in FIG. .

The electromagnetic pump 7 is suspended and supported from the second part of the reactor vessel 1 by a suspension casing 20. The suspended casing 20 does not have a sealed structure, and the surrounding primary coolant and the inside of the suspended casing 20 are communicated with each other.
The primary coolant liquid level inside and the surrounding primary coolant liquid level are maintained at the same level.

The conduit 9 passes through the primary coolant to reach the upper part of the reactor vessel 1, passes through the upper surface of the hanging casing 20 in an airtight manner, and protrudes upward. It is connected to an internal cable placed within the tube 9.

In FIG. 2, the terminal end portion of the conduit 9 is formed into an eccentric enlarged portion 9b having a larger diameter than other portions, and a cylindrical conduit lid 21 is removably provided on the eccentric enlarged portion 9b. Further, an axial partition wall 22 is provided inside the conduit tube 9, and the inside of the conduit tube 9 is divided into cable passages 25 and 25 by the partition wall 22. Into these cable passages 25.25 are inserted internal cables 23.23 which are connected to the power supply cable C at a terminal box 24 provided on the peripheral surface of the eccentric side of the eccentric enlarged portion 9b.

A partition wall 27 is also provided in the conduit lid 21, which is continuous with the partition wall 22 and divides the lower part of the lid into two chambers, and of these two chambers, the chamber on the terminal 24 side has an axial flow mode 28. It is provided. Note that 26 in the figure indicates an internal cable penetration portion provided in the partition wall 22 and configured to be airtight.

Furthermore, the axial blower 28 inside the conduit cover 21
As shown in FIG. 3, the air blower is attached to a blower mounting plate 29 that crosses the chamber housing the blower in the lid, with its suction port located below the mounting plate 29.

In the embodiment with the above configuration, the axial blower 28 sucks gas from one of the cable passages 25 of the conduit 9, that is, from the cable passage on the side of the room where the axial blower 28 of the two lids is installed. It ejects through the upper space inside the lid toward the other wire passage.

As a result, the sealed gas is forced to circulate within the electromagnetic pump 7. This forced circulation of gas promotes gas convection, and the convecting gas exchanges heat with the primary coolant around the electrical conduit 9, thereby cooling the iron core and coil group.

With the above configuration, the gas convection within the electromagnetic pump 7 is increased, and the heat generated by the coil group and the iron core is efficiently discharged into the secondary coolant. Furthermore, since heat is exchanged with the primary coolant through the conduit, the temperature of the coil group and the iron core can be suppressed more than in conventional electromagnetic pumps.

Furthermore, even in the event of a failure of the axial blower, the conduit cover can be removed and replaced easily.

The present invention is not limited to the above embodiments. For example, it is also possible to provide cooling fins in the portion of the conduit that is immersed in the primary coolant to increase the cooling effect. moreover,
The number of wire passages in the conduit may exceed the two illustrated as necessary.

[Effects of the Invention] As is clear from Section -I-, the present invention has the following advantages: In the magnetic pump, it is possible to prevent the temperature inside the electromagnetic pump from increasing while recovering most of the heat generated by each coil group and each iron core in the primary coolant.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing a schematic configuration of a fast breeder reactor equipped with an electromagnetic pump 7, which is an embodiment of the present invention, FIG. 2 is an enlarged vertical sectional view of the main part of the embodiment, and FIG. Figure 2 is a cross-sectional view taken along the ■-■ line, Figure 4 is an enlarged vertical cross-sectional view of a conventional electromagnetic pump, and Figure 5 is an example of a liquid metal cooled fast breeder reactor that uses electromagnetic pump 7 as the primary main circulation pump. FIG. 6 is a schematic cross-sectional view showing the schematic configuration of a liquid metal cooled fast breeder reactor that employs a mechanical pump as a primary main circulation pump. 1 Reactor vessel 2 Reactor core 3 - Secondary main circulation pump 4 Intermediate heat exchanger 5 Liquid metal 7 Electromagnetic pump 8 Two-part space 9
Conduit 9a ・Terminal configuration 9b Eccentric enlarged part 10
Inner core 11...Outer core 12...Annular flow path 13...Inner coil group] 4 Outer coil group 15
Central channel 17 ・Inner duct] 8... Outer duct i~ 19 Filled gas 20- Hanging casing 21 Conduit cover 22. 27 Partition wall 23... Internal cable 24 ・Terminal box 25... Cable passage 26 ・Cable penetration part 28...Axial flow blower 29...Blower mounting plate

Claims (1)

[Claims] A conduit through which an internal cable for feeding power to a group of coils for electromagnetic induction is inserted has at least two cable passages, and an eccentric enlarged portion is provided at an end of the conduit that protrudes outside the reactor vessel, An electromagnetic pump characterized in that a blower for forcedly circulating the sealed gas through the cable passage is provided in a cylindrical conduit lid detachably attached to the electromagnetic pump.