JPS5855018A - Electromagnetic filter - Google Patents

Abstract

PURPOSE:To improve a removing rate of magnetic foreign substance contained in a fluid, by providing a non-magnetic capsule in the central part of an electromagnetic coil along the direction of fluid flow, and making the fluid flow only in the vicinity of the inside of the coil where the intensity of magnetic field is large. CONSTITUTION:A group of iron balls 3 being magnetic granular bodies is provided to the inside of a non-magnetic pipe 2 having an annular magnetic field generating coil 1 arranged at the outer peripheral part of it. In the central part of the group 3 equivalent to the central part of the coil 1, a streamline shape non-magnetic capsule 5 is provided along the flow direction of a fluid 4 to be treated, and a pair of magnetic discs 7 having fluid through-holes 6 supports the capsule 5 at its upper and lower parts and fixes it to the inner wall of the pipe 2. Thus, as the fluid 4 to be treated such as cooling water passes only the vicinity of the inner surface of the coil 1 having a large magnetic field intensity without passing the central part having a small magnetic field intensity, the attraction of magnetic foreign substance is promoted and the removing rate of the materials are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in electromagnetic filters for removing magnetic contaminants in fluids.

Conventionally, electromagnetic filters have been used to remove magnetic contaminants such as iron from the cooling water used in large quantities in nuclear and thermal power applications to prevent corrosion of pipes and clogging of piping elements. .

As shown in Fig. 1, the electromagnetic filter basically consists of a magnetic generating coil 1 wound with a large number of dry or water-cooled conductors.
600φ~2000φ non-magnetic (S
In this system, spherical or piece-shaped magnetic grains 3 with fluid flow gaps are provided inside the piping 2 (made in US) to adsorb magnetic contaminants in the cooling water 4.

However, when we examine the magnitude of the magnetic field (magnetic flux density) in the coil 1, we find that in the radial direction r6 of the coil 1 as shown in Fig. 2(a), the inner surface of the coil is at its maximum and the coil center O is the largest as shown in Fig. 2(b). Minimum.

In addition, in the axial direction 10 of the coil 1 as shown in FIG. 2(a),
As shown in FIG. 2(C), the coil center 10 is the maximum and the coil ends are the minimum.

Therefore, the attraction force is large at the center of the coil where the magnetic grains 3 are strongly magnetized, and the attraction force is small at the center of the coil, and the attraction force at the ends of the coil is also smaller than at the center, which causes a biased phenomenon. The cooling water flowing through the center of the coil, that is, the center of the pipe 2, had a tendency to pass through the filter without removing iron and the like. This tendency becomes more pronounced as the inner diameter of the coil becomes larger compared to the height of the coil.

The present invention has been made in view of the above-mentioned and conventional problems, and is constructed by providing a streamlined non-magnetic capsule in the fluid flow direction in the center of magnetic grains corresponding to the center of the coil, thereby distributing the fluid. The fluid is made to flow only toward the inner surface of the coil where the magnetic field is large, thereby improving the removal rate of magnetic contaminants in the fluid.

Embodiments of the invention will now be described in detail with reference to the accompanying drawings.

As shown in Figure 3, an annular magnetic field generating coil 1 is disposed on the outer periphery of the non-magnetic pipe 2, and inside the pipe 2 corresponding to the magnetic field generating coil 1, magnetic grains of iron are arranged. A ball group 3 is provided.

At the center of the iron ball group 3 corresponding to the center of the coil 1, that is, at the center of the pipe 2, there is a streamlined shape in the direction of flow of the cooling water 4, as shown in FIGS. 4 and 5. A non-magnetic capsule 5 is provided, the capsule 5 having a fluid passage hole 6. . . . The pipe 2 is vertically supported by a pair of magnetic discs 7°7 having 6
is fixed to the inner wall of the pair of magnetic disks 7.
, 7, the iron ball group 3 is held by a ball holder 12.

The capsule 5 is made of SUS (non-magnetic material), for example, and has a cylindrical body 5a integrally formed with a conical upper part 5b and a lower part 5C to form a hollow interior, and has a streamlined shape as a whole. .

Since the center portion occupies a small proportion of the internal cross-sectional area of the pipe 2, the loss resistance of the cooling water 4 does not increase significantly even if the capsule 5 is provided.

When installing the capsule 5 in the center of the pipe 2, as shown in FIG.
000 Gauss), capsule 5 in the shaded area
By providing this, the cooling water 4 does not pass through the center where the magnetic field is small, but flows only toward the inner surface of the coil where the magnetic field is large.
Adsorption of magnetic contaminants is promoted and the removal rate is improved.

This is shown in FIG. 9(a) of the conventional structure without the capsule 5.

FIG. 9(b) and FIG. 10(a) of the present application with capsule 5.
) and FIG. 10(b) in comparison. In addition, in the case where a central magnetic field reinforcing coil 9, which will be described later, is provided, the coil 1
The composite magnetic field C of the magnetic field a caused by the coil 9 and the magnetic field caused by the coil 9
The state is shown in FIGS. 10(a) and 10(b).

In addition, since the pair of magnetic disks 7, 7 form a good magnetic circuit with the coil 1, it is possible to correct the bending of the magnetic flux at the end of the coil, and the magnetic field in the radial and axial directions of the coil 1 can be corrected. This will make it possible to achieve uniformity.

This is compared to the conventional structure without the magnetic disk 7 in FIG.
2(b) and FIG. 13(a) of the present application with the magnetic disk 7.
, is shown in comparison with FIG. 13(b).

On the other hand, as shown in FIG.
A central magnetic field reinforcing coil 9 can be provided in the center.

If the coil 9 is used in combination with the magnetic field generating coil 1, the magnetic field at the end of the coil will be strengthened.

In addition, as shown in FIG. 7, the inside 8 of the non-magnetic capsule 5
A pair of central field reinforcement coils 10.11 can be provided on either side of the center.

If the coils io and ti are used together with the magnetic field generating coil 1, the magnetic field at both the ends of the coil and the center of the coil will be strengthened.

When installing the central magnetic field reinforcing coil 9 inside the capsule 5, as shown in FIG. , a split structure in which the lead wire 16 is drawn out, or an integrated structure in which the capsule 5 is fixed to the pipe 17 and the lead wire 16 is drawn out, as shown in FIG. The shape, position, number, etc. of 9.10.11 can be changed as appropriate.

As is clear from the above description, the present invention provides a streamlined non-magnetic capsule at the center of the magnetic particles, which corresponds to the center of the coil in an electromagnetic filter, so that the loss resistance of the fluid can be reduced. The fluid can be made to flow only toward the inner surface of the coil where the magnetic field is large without increasing the magnetic field so much, and the removal rate of magnetic contaminants in the fluid can be improved.

In addition, since only a capsule is provided, the structure is extremely simple and inexpensive, and furthermore, it can be applied to existing electromagnetic filters with only slight modifications.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a conventional electromagnetic filter, Figure 2 (a)
is a cross-sectional view of the magnetic field generating coil, FIG. 2(b) is a graph showing the magnitude of the magnetic field in the radial direction, FIG. 2(C) is a graph showing the magnitude of the magnetic field in the axial direction, and FIG. 3 is a graph showing the magnitude of the magnetic field in the axial direction. 4 is a perspective view of a capsule, FIG. 5 is a plan view of FIG. 4, FIGS. 6 and 7 are sectional views of an electromagnetic filter having a central magnetic field reinforcing coil, and FIG. The figures are magnetic flux density diagrams of piping, Figures 9(a) and 9(b), and Figure 10(
a) and Fig. 10(b), Fig. 11(a) and Fig. 11(b)
) are explanatory diagrams of the relationship between the coil and the magnetic flux density, respectively.
b) is an explanatory diagram of the relationship between the magnetic disk and magnetic flux density, and the first
4(a) and 14(b) are sectional views of the capsule mounting structure, respectively. 1... Magnetic field generating coil, 2... Non-magnetic piping, 3...
・Iron ball group, 4...Cooling water, 5...Non-magnetic capsule,
6...Fluid hole, 7...Magnetic disk, 8...Inside,
9゜10.11...Central magnetic field strengthening coil. Patent applicant Fuji Electric Seizo Co., Ltd. Agent Patent attorney Aoyama Aoyama 2 people Figure 2 (0) 3rd! lj 4th Ill 5all Figure 6 Figure 8 J: #. 911 (b) 11th mountain) Figure 11 (b) 12 ■ (0) 1211 (b) - Figure 14 (0) Figure 13 (0) Figure 14 (b)

Claims (3)

[Claims] (1) Spherical or piece-shaped magnetic grains with a fluid circulation gap are provided inside a non-magnetic pipe with a magnetic field generating coil arranged on the outer periphery, and the magnetic grains are magnetized by the coil to generate magnetism in the fluid. An electromagnetic filter for adsorbing contaminants, characterized in that a non-magnetic capsule is provided in the fluid flow direction at the center of the magnetic grains corresponding to the center of the coil. (2) The capsule is supported by a pair of magnetic disks having fluid passage holes, and the magnetic particles are held between the pair of magnetic disks. The electromagnetic filter described in item 1). (3) Claim (1) or (3) characterized in that the capsule has a built-in central magnetic field reinforcing coil.
The electromagnetic filter according to any of item 2).