JPH1048015A - Electromagnetic flow meter - Google Patents

Abstract

(57) [Problem] To provide an electromagnetic flowmeter which is easily connected to a counterpart pipe and is improved so as not to be affected by the material of the counterpart pipe. SOLUTION: In an electromagnetic flowmeter of a type inserted between flanges of a pair of mating pipes and fixed by connecting both flanges with bolts, the front end of the electromagnetic flowmeter is matched with the inner diameter of the previous electromagnetic flowmeter. A grounding ring made of a ferromagnetic material that acts as a ground for the fluid to be measured. , So that it is not affected by the material of the other pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic flowmeter which is inserted between flanges of a pair of mating pipes and fixed by connecting both flanges by bolts. The present invention relates to an electromagnetic flowmeter which is easy and improved so as not to be affected by the material of a mating pipe.

[0002]

2. Description of the Related Art FIG. 3 is a piping mounting configuration diagram showing a state in which a conventional electromagnetic flowmeter is mounted on a piping. 10, 11
Is a mating pipe for mounting the electromagnetic flow meter 12,
10a and 11a are flanges of the counterpart pipes 10 and 11, respectively.

The electromagnetic flow meter 12 has flanges 10a and 11
a through the earth rings 13 and 14
a, 15b, 15c,... are fixed.

The earth rings 13 and 14 are formed in an annular shape, and are made of, for example, a non-magnetic material such as stainless steel, and the inner surfaces thereof are fixed so as to be in direct contact with the fluid to be measured. I have.

[0005] The electromagnetic flow meter 12 is provided with pieces 16a, 16b, 16c, 16c, 16c, 16c having predetermined dimensions based on the positions of bolts 15a, 15b, 15c,.
The other side pipe 1
It is fixed so as to coincide with the central axis of the conduits 0 and 11.

[0006]

However, when the above-mentioned wafer type electromagnetic flowmeter 12 is mounted on the counterpart pipes 10, 11, the above-mentioned wafer type electromagnetic flowmeter 12 is formed by flanges 10a and 11a having a pitch circle corresponding to the flange standard. The bolts 15a, 15b, 15c,..., Etc., whose positions are defined, are used by the pieces 16a, 16b, 16c,.
2 can be fixed so as to match the pipe diameter.

However, the earth rings 13, 14 are inserted between the electromagnetic flowmeter 12 and the mating pipes 10, 11, and are fixed by bolts 15a, 15b, 15c,. It is difficult to fix it so as to exactly match the inside diameter of the eleventh.

Another problem arises with this type of electromagnetic flow meter. This will be described with reference to FIG.
FIG. 4 is a longitudinal sectional view corresponding to the plan view shown in FIG. As shown in the drawing, the exciting coil 1 is provided inside the electromagnetic flowmeter 12.
The excitation coils 17a and 18a generate a magnetic field B and apply it to a measurement fluid flowing therein.

The magnetic field B in this case is, as shown by the dotted line, from the center of the donut-shaped exciting coils 17a, 18a to the surrounding non-magnetic earth rings 13, 14 and the mating pipe 1
A distribution reaching 0 and 11 is shown.

There are various cases where the mating pipes 10 and 11 are made of a magnetic material such as iron or a non-magnetic material such as vinyl chloride. Therefore, in the case of the wafer type electromagnetic flow meter 12 as shown in FIG. 3, the state of the magnetic field B differs according to the type of the counterpart piping, the strength of the magnetic field B varies, and the span varies according to the installation state. Failure occurs.

[0011]

SUMMARY OF THE INVENTION The present invention is, as a configuration for solving the above-mentioned problems, a type in which a flange is inserted between a pair of mating pipes and both flanges are connected by bolts and fixed. The electromagnetic flowmeter has a contact portion for positioning and fixing the bolt as a guide together with a fixture for fixing to the case of the electromagnetic flowmeter so as to match the inner diameter of the electromagnetic flowmeter. An earth ring made of a ferromagnetic material that acts as a ground is provided at both ends so that the material is not affected by the material of the other pipe.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing the configuration of the present invention, and FIG. 2 is a longitudinal sectional view when the electromagnetic flow meter shown in FIG. 1 is attached to a counterpart pipe. Parts having the same functions as those of the conventional electromagnetic flow meter shown in FIGS. 3 and 4 are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

FIG. 1A is a side view, and FIG. 1B is a plan view. Reference numeral 20 denotes an electromagnetic flowmeter according to the present invention, which is composed of a main body 21 and earth rings 22 and 23 as shown in FIG.

The main body 21 has a cylindrical portion 2 through which a fluid to be measured flows.
4, a connecting part 25 connected to the cylindrical part 24, and a converting part 26 via the connecting part 25 are integrally formed.

Earth rings 22 and 23 are fixed to both ends of the cylindrical portion 24, respectively. Earth ring 2
Since 2 and 23 have the same shape, the description will be made based on the earth ring 22.

As shown in FIG. 1A, the shape of the earth ring 22 is, for example, four fixing members 27 at a portion corresponding to the external dimension D ₁ of the case of the cylindrical portion 24 of the electromagnetic flow meter 20.
27a are formed by being bent in the axial direction of the cylindrical portion 24, and a screw hole 28a for fixing the case to the case is formed in the fixing tool 27a and the like.

Further, since the center diameter D ₂ of the bolt corresponding to the flange standard of the mating pipes 10, 11 is predetermined, the bolts 29 a, 29 b, 29 c, determined by the standard based on the center diameter D ₂ are used. Considering the diameter of 29d, a part of the outer shape of the earth ring 22 is formed as a contact portion 30a, 30b, 30c, 30d in an arc shape in a direction in which a part of the outer shape is curved toward the center so as to contact the bolts 29a to 29d. Have been.

As described above, the earth ring 22
The fixtures 27a to 27d are positioned so that the inner diameter of the cylindrical portion 24 and the inner diameter of the earth ring 22 coincide with each other. Will be fixed as follows.

For this reason, according to the embodiment shown in FIG. 1, the main body 21, the earth rings 22 and 23, and the mating pipes 10 and 11 do not have a step at the inner diameter portion thereof, and are integrally and uniformly formed. Can be fixed.

Further, the earth rings 22 and 23
Can be made less susceptible to the influence of the mating pipe by using a magnetic material as its material. This will be described with reference to a longitudinal sectional view shown in FIG.

Inside the cylindrical portion 24, flanges 3 are provided at both ends.
A stainless steel conduit 31 having 1a and 31b is provided, and a lining 32 of an insulating material such as tetrafluoride resin is provided on an outer surface thereof. Exciting coils 33a and 33b are arranged inside the inside.

The flanges 31a, 31b of the lining 32
Earth rings 22 and 23 respectively
Is attached, and the cylindrical portion 24 is connected via a fixture 27d or the like.
Is fixed to the case.

When an exciting current is applied by connecting the exciting coils 33a and 33b in series, for example, a magnetic field B is generated as shown by a dotted line in FIG.
Since 3 is made of a magnetic material, the outer magnetic flux returns via the earth rings 22 and 23.

As a result, the magnetic field B is changed to
Since the ratio of passing through the pipe 11 decreases,
The material such as the material No. 1 does not affect the performance such as the span change, and a thinner electromagnetic flowmeter can be realized when the same performance as the conventional one is maintained.

[0025]

According to the present invention, as described above in detail with the embodiments of the present invention, positioning and fixing are performed by using bolts as guides together with fixing tools for fixing to the case so as to match the inner diameter of the electromagnetic flowmeter. The ground ring is made of a ferromagnetic material that has a contact portion that makes contact with the fluid to be measured and has a grounding function at both ends. The pipe and the pipe can be fixed integrally as one unit without any step at the inner diameter part, and furthermore, it is possible not to be affected by the material or type of the mating pipe.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a state when the electromagnetic flow meter shown in FIG. 1 is fixed to a pipe.

FIG. 3 is a plan view showing a configuration when a conventional electromagnetic flowmeter is installed in a pipe.

FIG. 4 is a longitudinal sectional view for explaining a problem of the electromagnetic flow meter shown in FIG. 3;

[Explanation of symbols]

 10, 11 Mating pipe 12, 20 Electromagnetic flow meter 10a, 11a Flange 13, 14, 22, 23 Earth ring 15a, 15b, 15c Bolt 16a, 16b, 16c Piece 17a, 17b, 33a, 33b Excitation coil 21 Main body 24 Cylindrical part 25 Connection part 26 Conversion part 27a, ..., 27d Fixture 29a, 29b, 29c, 29d Bolt 30a, 30b, 30c, 30d Contact part 31 Conduit 32 Lining

Claims (1)

[Claims] 1. An electromagnetic flow meter of a type inserted between flanges of a pair of mating pipes and fixed by connecting the two flanges with bolts, wherein the electromagnetic flow rate is set to coincide with the inner diameter of the electromagnetic flow meter. A grounding ring made of a ferromagnetic material which has a contact portion for positioning and fixing the bolt as a guide together with a fixture for fixing to a case of the meter and which is made of a ferromagnetic material which acts to ground the fluid to be measured. An electromagnetic flowmeter characterized by being unaffected by the material of the piping.