JPH03289518A - Electromagnetic flowmeter provided with grounding ring having gasket - Google Patents

Abstract

PURPOSE:To ensure airtightness by the minimum tightening and to prevent leakage of liquid for a long period by providing spot facings in the facing pattern at the contact parts of both surfaces of a grounding ring, assembling rubber gaskets at this part, and vulcanizing and bonding the gaskets. CONSTITUTION:A grounding ring 7a for grounding the potential of fluid to be measured is provided in an electromagnetic flowmeter. In this flowmeter, spot facings are provided in a facing pattern in the axial direction of the pipe of the ring 7a. Thick rubber gaskets 8a and 9a are assembled in recess parts. One surface of the ring 7a is vulcanized and bonded. The spot faces of the ring 7a serve the role of outer rings for preventing the protruding deformation of the gaskets in the direction of the radius when high pressure is applied on the gaskets 8a and 9a. Since the gaskets 8a and 9a are vulcanized and bonded, they withstand the deformation in the radial direction with the bonding strength during the water-passing operation. Thus the leakage of liquid is prevented. In this way, airtightness can be ensured with the minimum tightening load, and the leakage of the liquid can be prevented for a long period.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the structure of an electromagnetic flowmeter equipped with an earth ring and a gasket, and is suitable for measuring the flow rate of high-pressure and high-temperature fluids.
The present invention relates to a suitable electromagnetic flowmeter detector that provides sufficient airtightness at the part where the connecting piping flange and the detector are in contact.

[Conventional technology]

As described in Japanese Patent Application Laid-Open No. 124823/1982, the shape and structure of the conventional device was studied regarding an electromagnetic flowmeter having a ceramic conduit, but the problem was that the bolts were tightened only once when installed in the piping. No consideration was given to eccentric loads due to piping misalignment, twisting, etc.

[Problem to be solved by the invention]

The conventional device described above has a structure in which a plate-shaped gasket is inserted between each component to ensure airtightness when connecting and installing the ceramic conduit and earth ring to the piping flange. Due to eccentric loads due to misalignment, twisting, etc., and because asbestos is the main gasket material, over-tightening often occurs in anticipation of the thickness decreasing over time.
This caused the problem that the ceramic conduit would crack.

Furthermore, in the structure shown in FIG. 5 in which a plate-shaped gasket is inserted, the gasket pops out in the radial direction when the fluid pressure exceeds 20 kgf/a#, so it is not suitable for high-pressure fluid.

The purpose of the present invention is to ensure sufficient airtightness in the liquid leakage prevention section composed of a ceramic conduit, an earth ring, a gasket, and a connecting piping flange, to absorb various eccentric loads, and to make the installation timely. An object of the present invention is to provide an electromagnetic flowmeter with improved workability.

[Means to solve the problem]

In order to achieve the above purpose, a counterbore surface is provided facing the contact area of the surface of the ground ring, a rubber gasket is incorporated into this part, and one side of the gasket on the ground ring side is vulcanized and bonded to form an integral structure. I made it.

Furthermore, in order to facilitate centering during installation, the gasket should have at least one convex cross section on the connecting surface opposite to the surface that is bonded to the ground ring. This is what I did.

[Effect]

In the electromagnetic flowmeter of the present invention, because of the integral structure of the gasketed earth ring, there is no need for excessive tightening load during assembly, and it is possible to prevent eccentric loads and prevent the ceramic conduit from cracking.

Additionally, the counterbore surface of the ground ring acts as a stopper for the outer ring to prevent the gasket from popping out, making it possible to use soft rubber with a small gasket coefficient.
Sufficient airtightness can be ensured even when measuring high-pressure fluids.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. 1st
In the figure, the electromagnetic flowmeter of the present invention includes a conduit 1 made of ceramic (for example, A Excitation coils 3a, 3 each generate a magnetic field in a direction perpendicular to the axis connecting the electrodes of
b is an iron core that creates a highly efficient magnetic field4. Outer cylinder for housing the magnetic field generator while ensuring waterproofness 5. Box 6° indicating a relay terminal or converter for wiring such as an excitation coil or electrode lead wire Bypassing the fluid current in the measured flow rate to the ground via the ground wire, reducing the influence of noise and reducing the flow rate signal voltage An earth ring 7a that provides a ground potential.

7b, gaskets 8a and 8b for airtightness between the ceramic conduit flare portion and the earth ring, gaskets 9a and 9b for airtightness between the earthing ring and the connecting pipe flange,
The earth ring and gasket have an integral structure, and are fixed to the outer cylinder 5 by the earth ring fixing claw to establish an electrical connection.
These constitute an electromagnetic flowmeter detector. The detector is disposed between the connecting piping flanges 10a and 10b, and is fixed to the piping by being inserted with bolts 11 and nuts 12.

FIG. 2 is a detailed view of the integrated structure of the earth ring with gasket according to the present embodiment explained in FIG. 1.

The grounding ring 7a shown in Fig. 2 has countersunk surfaces facing each other in the tube axis direction, thick rubber gaskets 8a and 9a are installed in these recesses, and one surface on the grounding ring side is vulcanized and bonded. The structure is as follows.

Here, the counterbore surface of the earth ring 7a is under high pressure (40k
When pressure of gf/a#) is applied to the gaskets 8a and 9a, the gasket 8a serves as an outer ring to suppress deformation that pops out in the radial direction.

Since 9a is vulcanized and bonded to the ground ring 7a,
Since the receiver is able to withstand deformation that pops out in the radial direction during water flow operation using adhesive strength rather than the flange tightening load, liquid leakage can be effectively prevented. That is, since the gaskets 8a and 9a that fly in the radial direction have adhesive strength, the rubber hardness is low.

In addition, since a thick-walled soft gasket can be used, applicability to eccentric loads is improved, and furthermore, since the tightening load can be minimized, cracking of the ceramic conduit l can be effectively prevented.

Although one embodiment of the present invention has been described above, the material of the gasket described above is not limited to a certain number of materials, but may be selected depending on the temperature and pressure of the fluid to be measured. By doing so, airtightness can be maintained, and unsaturation and
It is clear that any synthetic rubber that can be vulcanized and bonded, such as saturated rubber, can be used in the electromagnetic flowmeter of this structure.

3 and 4 show other embodiments of the invention,
Identical members are given the same reference numerals.

FIG. 3 shows that the connecting surfaces of the gaskets 8a', 9a' opposite to the vulcanized bonding surfaces are shaped to have a convex cross section, thereby further improving the self-sealing property between the gaskets and the connecting pipes. FIG. 4 shows a gasket located between the earth ring and the connecting piping flange, which is provided with a full-face gasket with bolt holes for the flange, and furthermore, the configuration allows easy centering of the detector and piping.

〔Effect of the invention〕

The structure of the electromagnetic flowmeter of the present invention allows the use of a thick soft rubber gasket in the liquid leakage prevention section. Therefore, the installation of electromagnetic flowmeters sometimes occurs. It absorbs various eccentric loads and ensures sufficient airtightness with minimal tightening, which prevents cracks in the ceramic conduit and prevents liquid leakage over the long term.

In addition, since the earth ring and gasket are integrated, centering is easier when installing the detector, which also has the effect of improving work efficiency.

[Brief explanation of drawings]

FIG. 1 is a half-section and side view of a detector according to an embodiment of the present invention, FIG. 2 is a detailed diagram of the invention in FIG. 1, and FIGS. The figure shows one conventional example. 1... Ceramic conduit, 2a, 2b... Electrode, 3
a. 3b... Excitation coil, 4... Iron core, 5... Outer cylinder,
6...Box, 7a, 7b...Earth ring, 8
a, 8b...gasket, 8a', 9a', 9a
... Gaskets of other embodiments, 9a, 9b... Gaskets, 10a, 10b... Connection piping flange, 1
1... Bolt, 12... Nut, 13a... Conventional earth ring.

Claims (1)

[Claims] 1. In an electromagnetic flowmeter equipped with a grounding ring that performs potential grounding of the fluid to be measured, a counterbore surface is provided at the connecting portion on both sides of the grounding ring, and a rubber gasket is incorporated into the counterbore surface. , an electromagnetic flowmeter equipped with a ground ring with a gasket, characterized in that the contact surface of the ground ring and the gasket is vulcanized and bonded. 2. The gasket according to claim 1, wherein the gasket has at least one convex cross section on the connection surface opposite to the hot-flow bonding surface with the ground ring. An electromagnetic flowmeter with a grounding ring.