JPH04127021A - Structure of electrode part of electromagnetic flowmeter detector - Google Patents

Abstract

PURPOSE:To prevent the insulation deterioration of an electrode and to improve the flow rate characteristics of a detector by forming an insulating tube in the mold lining, and clamping the lining by the electrode in a manner not to generate a space of the lining between the electrode and a pipe hole. CONSTITUTION:A lining 2 is formed in the mold lining through injection molding and molded from the inner face to a flange flare part of a pipe. A pipe hole 1b is coated all over the surface thereof with the lining 2 in a manner not to generate a room of the lining 2 between an electrode 3 and the pipe hold 1b. A hole of the same tapering angle as that of the electrode 3 is formed in the pipe hole 1b. When the electrode 3 is inserted into the tapered hole and clamped by a nut 7, a room of the lining 2 is never formed. Therefore, even if the water or liquid penetrates from a gap (g) between the flange 8 and the lining flare 2a, the insulating resistance of the electrode 3 is not deteriorated, thereby improving the flow rate characteristics.

Description

[Detailed Description of the Invention] C. Industrial Application Field] The present invention provides an electrode part structure of an electromagnetic flowmeter detector that improves flow characteristics without reducing the insulation resistance of the electrode. Regarding.

[Prior Art] The structure of the electrode section including the flange section of a conventional electromagnetic flowmeter detector is shown in FIG.

A pair of holes 1b into which electrodes 3 are inserted are opened from the outer surface of the vibrator 1 so as to face each other at the center of the tube axis of the pipe 1. The pipe hole 1b is processed so that the inside of the pipe 1 widens in a tapered shape.

An insulating tube as a lining 2 is inserted into the inner wall surface of the pipe 1, and the lining 8 is applied to the pipe 1 by turning back both sides along the flange 8 to near the outer peripheral surface of the flange 8.

Next, as shown in FIG. 4, a hole is made in the lining 2 concentrically with the pipe hole 1b and smaller than the pipe hole 1b. Pipe 1.
A countersunk screw-shaped electrode 3 is inserted into the through hole of the lining 2 from the inside of the lining 2, as shown in FIG. 2, and pulled out to the outside of the pipe I.

To the axis of the pulled out electrode 3, press 4. Wa 5. Insert the Swarovski in this order and tighten with nut 7. The electrode detects the electromotive force generated in the liquid to be measured inside the lining 2, and is insulated from the pipe 1 by the lining 2 and the jet 4. Lining 2 seals the measuring liquid flowing inside the pipe.
A dovetail groove 3a is provided in the tapered part of the electrode 3,
By tightening the electrode 3, the lining 2 enters into the dovetail groove 3a, and the contact pressure between the lining 2 and the electrode 3 increases, resulting in a structure that can withstand the pressure of the liquid to be measured and does not leak in the pipe. Ta.

[Problems to be Solved by the Invention] In many cases, the detector is exposed to water or liquid due to flooding, rain, or leakage of measurement liquid from the flange. Lining 2 material is glued to pipe 1, but lining 2
When the material is made of tetrafluoroethylene resin, the adhesive strength cannot be expected to be sufficiently waterproof. Therefore, water or liquid applied to the flange portion penetrates into the gap g between the flange 8 and the lining flare 2a, and gradually advances to reach the electrode portion. By tightening the electrode 3, the pipe taper hole 1a appears to have a secondary contact surface pressure. However, since the lining 2 is made of a thick and hard material, stress is generated to return the lining to the shape shown in Fig. 4, and the contact surface pressure between the taper hole la surface and the lining 2 cannot achieve a waterproof effect. .

Therefore, water or liquid contacts the electrode 3 and reduces the insulation resistance between the electrode 3 and the pipe 1. When the insulation resistance of electrode 3 decreases, the detected electromotive force of electrode 3 decreases, and in the worst case,
There was a problem where the output would become zero.

The object of the present invention is to provide a flange 8 and a lining flare-2a.
Second, the electrode part structure is such that even if water or liquid penetrates through the gap g between the electrodes, the insulation resistance of the electrode 3 is not reduced and the flow characteristics are improved.

[Means to solve the problem]

In order to achieve the above objective, the pipe hole is lined to cover the entire circumference of the pipe hole so that there is no lining space between the electrode and the pipe hole. It is compressed to increase the contact pressure between the pipe hole surface and the lining.

[Operation] When the pipe hole is lined to cover the entire circumference of the pipe hole so that no lining space is created between the electrode and the pipe hole, and the electrode is attached, the lining trapped between the electrode and the pipe is removed. The elasticity seals the contact surface between the pipe hole surface and the lining.

As a result, even if water or liquid penetrates into the gap between the flange and the lining flare, it is blocked by the pipe hole surface where the electrode is attached, so that the insulation resistance of the electrode does not decrease.

[Example] Hereinafter, an example of the present invention will be described with reference to FIG. The lining 2 is a mold lining made by injection molding,
Mold from the inner surface of the pipe to part of the flange flare. The electrode part has lining 2 between electrode 3 and pipe hole lb.
As shown in FIG. 3, a lining 2 is applied to the pipe hole 1b so as to cover the entire circumferential surface of the pipe hole 1b so as to prevent the formation of a space.

However, the axial diameter φd of the electrode 3 is located at the axial center of the pipe hole 1b.
1, the inner surface of the lining 2 has a through hole with an inversely tapered shape. The inversely tapered hole has the same taper angle φd2' as the taper of the electrode 3, which is slightly smaller than the electrode head diameter φd2.

Next, as shown in Fig. 1, the electrode 3 is inserted into the reverse tapered hole, and the electrode 3 is inserted into the inverted taper hole from the outside of the pipe. Wa 5. Insert the Swarovski into the three electrode shafts in this order and tighten with nuts 7.

The space between the electrode 3 and the vibrator hole 1b is covered with the lining 2 even when no torque is applied to the nut 7.
The space part disappears.

In addition to this, when tightening torque is applied to nut 7,
The lining 2 is compressed by the electrode 3, and the vicinity of the head of the electrode 3 acts to escape in the tube axis direction.

However, the lining 2 that has entered the tapered hole 1a of the pipe 1
acts elastically to escape from the pipe hole 1b to the outside of the pipe 1, but from the outside of the pipe l.

Since the lining 2 is held down by the Zetsuwa 4, it is in a trapped state.

Therefore, the lining 2 has a high contact surface pressure with the surface of the tapered hole 1a, and seals the surface of the tapered hole 1a.

According to the embodiment of the present invention, even if water or liquid penetrates through the flange flare part, it will not come into contact with the electrode.
This has the effect of not reducing the insulation resistance of the electrode.

[Effects of the Invention] According to the present invention, even if water or liquid penetrates into the gap between the flange and the lining flare due to flooding, rain, or leakage of the measuring liquid, the electrode compresses the lining trapped in the pipe hole. However, since the contact pressure between the large tapered surface of the pipe hole and the lining is increased, the insulation resistance of the electrode is not reduced.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of an electrode part including a flange part according to an embodiment of the present invention, FIG. 2 is a vertical cross-sectional view of a conventional electrode part including a flange part, and FIG. FIG. 4 is a longitudinal cross-sectional view of the electrode portion before attachment of the electrode of FIG. 2. FIG. 1... Pipe, 2... Lining, 3... Electrode,
4...zetsuwa, 5...wa, 6...swa, 7...
Nut, 8...flange, 1a...tapered hole, 1b
...Pipe hole, 2a...Research diagram Figure diagram

Claims (1)

[Claims] 1. Drill a pair of holes into which electrodes will be inserted facing each other from the outside of the pipe toward the center of the pipe axis, insert an insulating tube as a lining into the inside wall of the pipe, and install it along the end of the pipe. Line the pipe with flanges on both sides up to the outer circumferential surface of the flange. An electromagnetic flowmeter detector consists of making a hole in the lining that is concentric with the pipe hole and smaller than the pipe hole, inserting an electrode from inside the lining, pulling it out from the outside of the pipe, and tightening and fixing the electrode with a nut through an insulator. In the electrode part structure, the insulating tube is molded and lined by injection molding, and the pipe hole is lined to cover the entire circumference of the pipe hole so that there is no lining space between the electrode and the pipe hole. An electrode part structure of an electromagnetic flowmeter detector characterized by a lining that is confined in a lining that is tightened with an electrode.